Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/arch/ia64/kernel/perfmon.c b/arch/ia64/kernel/perfmon.c
new file mode 100644
index 0000000..71147be
--- /dev/null
+++ b/arch/ia64/kernel/perfmon.c
@@ -0,0 +1,6676 @@
+/*
+ * This file implements the perfmon-2 subsystem which is used
+ * to program the IA-64 Performance Monitoring Unit (PMU).
+ *
+ * The initial version of perfmon.c was written by
+ * Ganesh Venkitachalam, IBM Corp.
+ *
+ * Then it was modified for perfmon-1.x by Stephane Eranian and
+ * David Mosberger, Hewlett Packard Co.
+ *
+ * Version Perfmon-2.x is a rewrite of perfmon-1.x
+ * by Stephane Eranian, Hewlett Packard Co.
+ *
+ * Copyright (C) 1999-2003, 2005 Hewlett Packard Co
+ * Stephane Eranian <eranian@hpl.hp.com>
+ * David Mosberger-Tang <davidm@hpl.hp.com>
+ *
+ * More information about perfmon available at:
+ * http://www.hpl.hp.com/research/linux/perfmon
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/smp_lock.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/init.h>
+#include <linux/vmalloc.h>
+#include <linux/mm.h>
+#include <linux/sysctl.h>
+#include <linux/list.h>
+#include <linux/file.h>
+#include <linux/poll.h>
+#include <linux/vfs.h>
+#include <linux/pagemap.h>
+#include <linux/mount.h>
+#include <linux/version.h>
+#include <linux/bitops.h>
+
+#include <asm/errno.h>
+#include <asm/intrinsics.h>
+#include <asm/page.h>
+#include <asm/perfmon.h>
+#include <asm/processor.h>
+#include <asm/signal.h>
+#include <asm/system.h>
+#include <asm/uaccess.h>
+#include <asm/delay.h>
+
+#ifdef CONFIG_PERFMON
+/*
+ * perfmon context state
+ */
+#define PFM_CTX_UNLOADED 1 /* context is not loaded onto any task */
+#define PFM_CTX_LOADED 2 /* context is loaded onto a task */
+#define PFM_CTX_MASKED 3 /* context is loaded but monitoring is masked due to overflow */
+#define PFM_CTX_ZOMBIE 4 /* owner of the context is closing it */
+
+#define PFM_INVALID_ACTIVATION (~0UL)
+
+/*
+ * depth of message queue
+ */
+#define PFM_MAX_MSGS 32
+#define PFM_CTXQ_EMPTY(g) ((g)->ctx_msgq_head == (g)->ctx_msgq_tail)
+
+/*
+ * type of a PMU register (bitmask).
+ * bitmask structure:
+ * bit0 : register implemented
+ * bit1 : end marker
+ * bit2-3 : reserved
+ * bit4 : pmc has pmc.pm
+ * bit5 : pmc controls a counter (has pmc.oi), pmd is used as counter
+ * bit6-7 : register type
+ * bit8-31: reserved
+ */
+#define PFM_REG_NOTIMPL 0x0 /* not implemented at all */
+#define PFM_REG_IMPL 0x1 /* register implemented */
+#define PFM_REG_END 0x2 /* end marker */
+#define PFM_REG_MONITOR (0x1<<4|PFM_REG_IMPL) /* a PMC with a pmc.pm field only */
+#define PFM_REG_COUNTING (0x2<<4|PFM_REG_MONITOR) /* a monitor + pmc.oi+ PMD used as a counter */
+#define PFM_REG_CONTROL (0x4<<4|PFM_REG_IMPL) /* PMU control register */
+#define PFM_REG_CONFIG (0x8<<4|PFM_REG_IMPL) /* configuration register */
+#define PFM_REG_BUFFER (0xc<<4|PFM_REG_IMPL) /* PMD used as buffer */
+
+#define PMC_IS_LAST(i) (pmu_conf->pmc_desc[i].type & PFM_REG_END)
+#define PMD_IS_LAST(i) (pmu_conf->pmd_desc[i].type & PFM_REG_END)
+
+#define PMC_OVFL_NOTIFY(ctx, i) ((ctx)->ctx_pmds[i].flags & PFM_REGFL_OVFL_NOTIFY)
+
+/* i assumed unsigned */
+#define PMC_IS_IMPL(i) (i< PMU_MAX_PMCS && (pmu_conf->pmc_desc[i].type & PFM_REG_IMPL))
+#define PMD_IS_IMPL(i) (i< PMU_MAX_PMDS && (pmu_conf->pmd_desc[i].type & PFM_REG_IMPL))
+
+/* XXX: these assume that register i is implemented */
+#define PMD_IS_COUNTING(i) ((pmu_conf->pmd_desc[i].type & PFM_REG_COUNTING) == PFM_REG_COUNTING)
+#define PMC_IS_COUNTING(i) ((pmu_conf->pmc_desc[i].type & PFM_REG_COUNTING) == PFM_REG_COUNTING)
+#define PMC_IS_MONITOR(i) ((pmu_conf->pmc_desc[i].type & PFM_REG_MONITOR) == PFM_REG_MONITOR)
+#define PMC_IS_CONTROL(i) ((pmu_conf->pmc_desc[i].type & PFM_REG_CONTROL) == PFM_REG_CONTROL)
+
+#define PMC_DFL_VAL(i) pmu_conf->pmc_desc[i].default_value
+#define PMC_RSVD_MASK(i) pmu_conf->pmc_desc[i].reserved_mask
+#define PMD_PMD_DEP(i) pmu_conf->pmd_desc[i].dep_pmd[0]
+#define PMC_PMD_DEP(i) pmu_conf->pmc_desc[i].dep_pmd[0]
+
+#define PFM_NUM_IBRS IA64_NUM_DBG_REGS
+#define PFM_NUM_DBRS IA64_NUM_DBG_REGS
+
+#define CTX_OVFL_NOBLOCK(c) ((c)->ctx_fl_block == 0)
+#define CTX_HAS_SMPL(c) ((c)->ctx_fl_is_sampling)
+#define PFM_CTX_TASK(h) (h)->ctx_task
+
+#define PMU_PMC_OI 5 /* position of pmc.oi bit */
+
+/* XXX: does not support more than 64 PMDs */
+#define CTX_USED_PMD(ctx, mask) (ctx)->ctx_used_pmds[0] |= (mask)
+#define CTX_IS_USED_PMD(ctx, c) (((ctx)->ctx_used_pmds[0] & (1UL << (c))) != 0UL)
+
+#define CTX_USED_MONITOR(ctx, mask) (ctx)->ctx_used_monitors[0] |= (mask)
+
+#define CTX_USED_IBR(ctx,n) (ctx)->ctx_used_ibrs[(n)>>6] |= 1UL<< ((n) % 64)
+#define CTX_USED_DBR(ctx,n) (ctx)->ctx_used_dbrs[(n)>>6] |= 1UL<< ((n) % 64)
+#define CTX_USES_DBREGS(ctx) (((pfm_context_t *)(ctx))->ctx_fl_using_dbreg==1)
+#define PFM_CODE_RR 0 /* requesting code range restriction */
+#define PFM_DATA_RR 1 /* requestion data range restriction */
+
+#define PFM_CPUINFO_CLEAR(v) pfm_get_cpu_var(pfm_syst_info) &= ~(v)
+#define PFM_CPUINFO_SET(v) pfm_get_cpu_var(pfm_syst_info) |= (v)
+#define PFM_CPUINFO_GET() pfm_get_cpu_var(pfm_syst_info)
+
+#define RDEP(x) (1UL<<(x))
+
+/*
+ * context protection macros
+ * in SMP:
+ * - we need to protect against CPU concurrency (spin_lock)
+ * - we need to protect against PMU overflow interrupts (local_irq_disable)
+ * in UP:
+ * - we need to protect against PMU overflow interrupts (local_irq_disable)
+ *
+ * spin_lock_irqsave()/spin_lock_irqrestore():
+ * in SMP: local_irq_disable + spin_lock
+ * in UP : local_irq_disable
+ *
+ * spin_lock()/spin_lock():
+ * in UP : removed automatically
+ * in SMP: protect against context accesses from other CPU. interrupts
+ * are not masked. This is useful for the PMU interrupt handler
+ * because we know we will not get PMU concurrency in that code.
+ */
+#define PROTECT_CTX(c, f) \
+ do { \
+ DPRINT(("spinlock_irq_save ctx %p by [%d]\n", c, current->pid)); \
+ spin_lock_irqsave(&(c)->ctx_lock, f); \
+ DPRINT(("spinlocked ctx %p by [%d]\n", c, current->pid)); \
+ } while(0)
+
+#define UNPROTECT_CTX(c, f) \
+ do { \
+ DPRINT(("spinlock_irq_restore ctx %p by [%d]\n", c, current->pid)); \
+ spin_unlock_irqrestore(&(c)->ctx_lock, f); \
+ } while(0)
+
+#define PROTECT_CTX_NOPRINT(c, f) \
+ do { \
+ spin_lock_irqsave(&(c)->ctx_lock, f); \
+ } while(0)
+
+
+#define UNPROTECT_CTX_NOPRINT(c, f) \
+ do { \
+ spin_unlock_irqrestore(&(c)->ctx_lock, f); \
+ } while(0)
+
+
+#define PROTECT_CTX_NOIRQ(c) \
+ do { \
+ spin_lock(&(c)->ctx_lock); \
+ } while(0)
+
+#define UNPROTECT_CTX_NOIRQ(c) \
+ do { \
+ spin_unlock(&(c)->ctx_lock); \
+ } while(0)
+
+
+#ifdef CONFIG_SMP
+
+#define GET_ACTIVATION() pfm_get_cpu_var(pmu_activation_number)
+#define INC_ACTIVATION() pfm_get_cpu_var(pmu_activation_number)++
+#define SET_ACTIVATION(c) (c)->ctx_last_activation = GET_ACTIVATION()
+
+#else /* !CONFIG_SMP */
+#define SET_ACTIVATION(t) do {} while(0)
+#define GET_ACTIVATION(t) do {} while(0)
+#define INC_ACTIVATION(t) do {} while(0)
+#endif /* CONFIG_SMP */
+
+#define SET_PMU_OWNER(t, c) do { pfm_get_cpu_var(pmu_owner) = (t); pfm_get_cpu_var(pmu_ctx) = (c); } while(0)
+#define GET_PMU_OWNER() pfm_get_cpu_var(pmu_owner)
+#define GET_PMU_CTX() pfm_get_cpu_var(pmu_ctx)
+
+#define LOCK_PFS(g) spin_lock_irqsave(&pfm_sessions.pfs_lock, g)
+#define UNLOCK_PFS(g) spin_unlock_irqrestore(&pfm_sessions.pfs_lock, g)
+
+#define PFM_REG_RETFLAG_SET(flags, val) do { flags &= ~PFM_REG_RETFL_MASK; flags |= (val); } while(0)
+
+/*
+ * cmp0 must be the value of pmc0
+ */
+#define PMC0_HAS_OVFL(cmp0) (cmp0 & ~0x1UL)
+
+#define PFMFS_MAGIC 0xa0b4d889
+
+/*
+ * debugging
+ */
+#define PFM_DEBUGGING 1
+#ifdef PFM_DEBUGGING
+#define DPRINT(a) \
+ do { \
+ if (unlikely(pfm_sysctl.debug >0)) { printk("%s.%d: CPU%d [%d] ", __FUNCTION__, __LINE__, smp_processor_id(), current->pid); printk a; } \
+ } while (0)
+
+#define DPRINT_ovfl(a) \
+ do { \
+ if (unlikely(pfm_sysctl.debug > 0 && pfm_sysctl.debug_ovfl >0)) { printk("%s.%d: CPU%d [%d] ", __FUNCTION__, __LINE__, smp_processor_id(), current->pid); printk a; } \
+ } while (0)
+#endif
+
+/*
+ * 64-bit software counter structure
+ *
+ * the next_reset_type is applied to the next call to pfm_reset_regs()
+ */
+typedef struct {
+ unsigned long val; /* virtual 64bit counter value */
+ unsigned long lval; /* last reset value */
+ unsigned long long_reset; /* reset value on sampling overflow */
+ unsigned long short_reset; /* reset value on overflow */
+ unsigned long reset_pmds[4]; /* which other pmds to reset when this counter overflows */
+ unsigned long smpl_pmds[4]; /* which pmds are accessed when counter overflow */
+ unsigned long seed; /* seed for random-number generator */
+ unsigned long mask; /* mask for random-number generator */
+ unsigned int flags; /* notify/do not notify */
+ unsigned long eventid; /* overflow event identifier */
+} pfm_counter_t;
+
+/*
+ * context flags
+ */
+typedef struct {
+ unsigned int block:1; /* when 1, task will blocked on user notifications */
+ unsigned int system:1; /* do system wide monitoring */
+ unsigned int using_dbreg:1; /* using range restrictions (debug registers) */
+ unsigned int is_sampling:1; /* true if using a custom format */
+ unsigned int excl_idle:1; /* exclude idle task in system wide session */
+ unsigned int going_zombie:1; /* context is zombie (MASKED+blocking) */
+ unsigned int trap_reason:2; /* reason for going into pfm_handle_work() */
+ unsigned int no_msg:1; /* no message sent on overflow */
+ unsigned int can_restart:1; /* allowed to issue a PFM_RESTART */
+ unsigned int reserved:22;
+} pfm_context_flags_t;
+
+#define PFM_TRAP_REASON_NONE 0x0 /* default value */
+#define PFM_TRAP_REASON_BLOCK 0x1 /* we need to block on overflow */
+#define PFM_TRAP_REASON_RESET 0x2 /* we need to reset PMDs */
+
+
+/*
+ * perfmon context: encapsulates all the state of a monitoring session
+ */
+
+typedef struct pfm_context {
+ spinlock_t ctx_lock; /* context protection */
+
+ pfm_context_flags_t ctx_flags; /* bitmask of flags (block reason incl.) */
+ unsigned int ctx_state; /* state: active/inactive (no bitfield) */
+
+ struct task_struct *ctx_task; /* task to which context is attached */
+
+ unsigned long ctx_ovfl_regs[4]; /* which registers overflowed (notification) */
+
+ struct semaphore ctx_restart_sem; /* use for blocking notification mode */
+
+ unsigned long ctx_used_pmds[4]; /* bitmask of PMD used */
+ unsigned long ctx_all_pmds[4]; /* bitmask of all accessible PMDs */
+ unsigned long ctx_reload_pmds[4]; /* bitmask of force reload PMD on ctxsw in */
+
+ unsigned long ctx_all_pmcs[4]; /* bitmask of all accessible PMCs */
+ unsigned long ctx_reload_pmcs[4]; /* bitmask of force reload PMC on ctxsw in */
+ unsigned long ctx_used_monitors[4]; /* bitmask of monitor PMC being used */
+
+ unsigned long ctx_pmcs[IA64_NUM_PMC_REGS]; /* saved copies of PMC values */
+
+ unsigned int ctx_used_ibrs[1]; /* bitmask of used IBR (speedup ctxsw in) */
+ unsigned int ctx_used_dbrs[1]; /* bitmask of used DBR (speedup ctxsw in) */
+ unsigned long ctx_dbrs[IA64_NUM_DBG_REGS]; /* DBR values (cache) when not loaded */
+ unsigned long ctx_ibrs[IA64_NUM_DBG_REGS]; /* IBR values (cache) when not loaded */
+
+ pfm_counter_t ctx_pmds[IA64_NUM_PMD_REGS]; /* software state for PMDS */
+
+ u64 ctx_saved_psr_up; /* only contains psr.up value */
+
+ unsigned long ctx_last_activation; /* context last activation number for last_cpu */
+ unsigned int ctx_last_cpu; /* CPU id of current or last CPU used (SMP only) */
+ unsigned int ctx_cpu; /* cpu to which perfmon is applied (system wide) */
+
+ int ctx_fd; /* file descriptor used my this context */
+ pfm_ovfl_arg_t ctx_ovfl_arg; /* argument to custom buffer format handler */
+
+ pfm_buffer_fmt_t *ctx_buf_fmt; /* buffer format callbacks */
+ void *ctx_smpl_hdr; /* points to sampling buffer header kernel vaddr */
+ unsigned long ctx_smpl_size; /* size of sampling buffer */
+ void *ctx_smpl_vaddr; /* user level virtual address of smpl buffer */
+
+ wait_queue_head_t ctx_msgq_wait;
+ pfm_msg_t ctx_msgq[PFM_MAX_MSGS];
+ int ctx_msgq_head;
+ int ctx_msgq_tail;
+ struct fasync_struct *ctx_async_queue;
+
+ wait_queue_head_t ctx_zombieq; /* termination cleanup wait queue */
+} pfm_context_t;
+
+/*
+ * magic number used to verify that structure is really
+ * a perfmon context
+ */
+#define PFM_IS_FILE(f) ((f)->f_op == &pfm_file_ops)
+
+#define PFM_GET_CTX(t) ((pfm_context_t *)(t)->thread.pfm_context)
+
+#ifdef CONFIG_SMP
+#define SET_LAST_CPU(ctx, v) (ctx)->ctx_last_cpu = (v)
+#define GET_LAST_CPU(ctx) (ctx)->ctx_last_cpu
+#else
+#define SET_LAST_CPU(ctx, v) do {} while(0)
+#define GET_LAST_CPU(ctx) do {} while(0)
+#endif
+
+
+#define ctx_fl_block ctx_flags.block
+#define ctx_fl_system ctx_flags.system
+#define ctx_fl_using_dbreg ctx_flags.using_dbreg
+#define ctx_fl_is_sampling ctx_flags.is_sampling
+#define ctx_fl_excl_idle ctx_flags.excl_idle
+#define ctx_fl_going_zombie ctx_flags.going_zombie
+#define ctx_fl_trap_reason ctx_flags.trap_reason
+#define ctx_fl_no_msg ctx_flags.no_msg
+#define ctx_fl_can_restart ctx_flags.can_restart
+
+#define PFM_SET_WORK_PENDING(t, v) do { (t)->thread.pfm_needs_checking = v; } while(0);
+#define PFM_GET_WORK_PENDING(t) (t)->thread.pfm_needs_checking
+
+/*
+ * global information about all sessions
+ * mostly used to synchronize between system wide and per-process
+ */
+typedef struct {
+ spinlock_t pfs_lock; /* lock the structure */
+
+ unsigned int pfs_task_sessions; /* number of per task sessions */
+ unsigned int pfs_sys_sessions; /* number of per system wide sessions */
+ unsigned int pfs_sys_use_dbregs; /* incremented when a system wide session uses debug regs */
+ unsigned int pfs_ptrace_use_dbregs; /* incremented when a process uses debug regs */
+ struct task_struct *pfs_sys_session[NR_CPUS]; /* point to task owning a system-wide session */
+} pfm_session_t;
+
+/*
+ * information about a PMC or PMD.
+ * dep_pmd[]: a bitmask of dependent PMD registers
+ * dep_pmc[]: a bitmask of dependent PMC registers
+ */
+typedef int (*pfm_reg_check_t)(struct task_struct *task, pfm_context_t *ctx, unsigned int cnum, unsigned long *val, struct pt_regs *regs);
+typedef struct {
+ unsigned int type;
+ int pm_pos;
+ unsigned long default_value; /* power-on default value */
+ unsigned long reserved_mask; /* bitmask of reserved bits */
+ pfm_reg_check_t read_check;
+ pfm_reg_check_t write_check;
+ unsigned long dep_pmd[4];
+ unsigned long dep_pmc[4];
+} pfm_reg_desc_t;
+
+/* assume cnum is a valid monitor */
+#define PMC_PM(cnum, val) (((val) >> (pmu_conf->pmc_desc[cnum].pm_pos)) & 0x1)
+
+/*
+ * This structure is initialized at boot time and contains
+ * a description of the PMU main characteristics.
+ *
+ * If the probe function is defined, detection is based
+ * on its return value:
+ * - 0 means recognized PMU
+ * - anything else means not supported
+ * When the probe function is not defined, then the pmu_family field
+ * is used and it must match the host CPU family such that:
+ * - cpu->family & config->pmu_family != 0
+ */
+typedef struct {
+ unsigned long ovfl_val; /* overflow value for counters */
+
+ pfm_reg_desc_t *pmc_desc; /* detailed PMC register dependencies descriptions */
+ pfm_reg_desc_t *pmd_desc; /* detailed PMD register dependencies descriptions */
+
+ unsigned int num_pmcs; /* number of PMCS: computed at init time */
+ unsigned int num_pmds; /* number of PMDS: computed at init time */
+ unsigned long impl_pmcs[4]; /* bitmask of implemented PMCS */
+ unsigned long impl_pmds[4]; /* bitmask of implemented PMDS */
+
+ char *pmu_name; /* PMU family name */
+ unsigned int pmu_family; /* cpuid family pattern used to identify pmu */
+ unsigned int flags; /* pmu specific flags */
+ unsigned int num_ibrs; /* number of IBRS: computed at init time */
+ unsigned int num_dbrs; /* number of DBRS: computed at init time */
+ unsigned int num_counters; /* PMC/PMD counting pairs : computed at init time */
+ int (*probe)(void); /* customized probe routine */
+ unsigned int use_rr_dbregs:1; /* set if debug registers used for range restriction */
+} pmu_config_t;
+/*
+ * PMU specific flags
+ */
+#define PFM_PMU_IRQ_RESEND 1 /* PMU needs explicit IRQ resend */
+
+/*
+ * debug register related type definitions
+ */
+typedef struct {
+ unsigned long ibr_mask:56;
+ unsigned long ibr_plm:4;
+ unsigned long ibr_ig:3;
+ unsigned long ibr_x:1;
+} ibr_mask_reg_t;
+
+typedef struct {
+ unsigned long dbr_mask:56;
+ unsigned long dbr_plm:4;
+ unsigned long dbr_ig:2;
+ unsigned long dbr_w:1;
+ unsigned long dbr_r:1;
+} dbr_mask_reg_t;
+
+typedef union {
+ unsigned long val;
+ ibr_mask_reg_t ibr;
+ dbr_mask_reg_t dbr;
+} dbreg_t;
+
+
+/*
+ * perfmon command descriptions
+ */
+typedef struct {
+ int (*cmd_func)(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs);
+ char *cmd_name;
+ int cmd_flags;
+ unsigned int cmd_narg;
+ size_t cmd_argsize;
+ int (*cmd_getsize)(void *arg, size_t *sz);
+} pfm_cmd_desc_t;
+
+#define PFM_CMD_FD 0x01 /* command requires a file descriptor */
+#define PFM_CMD_ARG_READ 0x02 /* command must read argument(s) */
+#define PFM_CMD_ARG_RW 0x04 /* command must read/write argument(s) */
+#define PFM_CMD_STOP 0x08 /* command does not work on zombie context */
+
+
+#define PFM_CMD_NAME(cmd) pfm_cmd_tab[(cmd)].cmd_name
+#define PFM_CMD_READ_ARG(cmd) (pfm_cmd_tab[(cmd)].cmd_flags & PFM_CMD_ARG_READ)
+#define PFM_CMD_RW_ARG(cmd) (pfm_cmd_tab[(cmd)].cmd_flags & PFM_CMD_ARG_RW)
+#define PFM_CMD_USE_FD(cmd) (pfm_cmd_tab[(cmd)].cmd_flags & PFM_CMD_FD)
+#define PFM_CMD_STOPPED(cmd) (pfm_cmd_tab[(cmd)].cmd_flags & PFM_CMD_STOP)
+
+#define PFM_CMD_ARG_MANY -1 /* cannot be zero */
+
+typedef struct {
+ int debug; /* turn on/off debugging via syslog */
+ int debug_ovfl; /* turn on/off debug printk in overflow handler */
+ int fastctxsw; /* turn on/off fast (unsecure) ctxsw */
+ int expert_mode; /* turn on/off value checking */
+ int debug_pfm_read;
+} pfm_sysctl_t;
+
+typedef struct {
+ unsigned long pfm_spurious_ovfl_intr_count; /* keep track of spurious ovfl interrupts */
+ unsigned long pfm_replay_ovfl_intr_count; /* keep track of replayed ovfl interrupts */
+ unsigned long pfm_ovfl_intr_count; /* keep track of ovfl interrupts */
+ unsigned long pfm_ovfl_intr_cycles; /* cycles spent processing ovfl interrupts */
+ unsigned long pfm_ovfl_intr_cycles_min; /* min cycles spent processing ovfl interrupts */
+ unsigned long pfm_ovfl_intr_cycles_max; /* max cycles spent processing ovfl interrupts */
+ unsigned long pfm_smpl_handler_calls;
+ unsigned long pfm_smpl_handler_cycles;
+ char pad[SMP_CACHE_BYTES] ____cacheline_aligned;
+} pfm_stats_t;
+
+/*
+ * perfmon internal variables
+ */
+static pfm_stats_t pfm_stats[NR_CPUS];
+static pfm_session_t pfm_sessions; /* global sessions information */
+
+static struct proc_dir_entry *perfmon_dir;
+static pfm_uuid_t pfm_null_uuid = {0,};
+
+static spinlock_t pfm_buffer_fmt_lock;
+static LIST_HEAD(pfm_buffer_fmt_list);
+
+static pmu_config_t *pmu_conf;
+
+/* sysctl() controls */
+static pfm_sysctl_t pfm_sysctl;
+int pfm_debug_var;
+
+static ctl_table pfm_ctl_table[]={
+ {1, "debug", &pfm_sysctl.debug, sizeof(int), 0666, NULL, &proc_dointvec, NULL,},
+ {2, "debug_ovfl", &pfm_sysctl.debug_ovfl, sizeof(int), 0666, NULL, &proc_dointvec, NULL,},
+ {3, "fastctxsw", &pfm_sysctl.fastctxsw, sizeof(int), 0600, NULL, &proc_dointvec, NULL,},
+ {4, "expert_mode", &pfm_sysctl.expert_mode, sizeof(int), 0600, NULL, &proc_dointvec, NULL,},
+ { 0, },
+};
+static ctl_table pfm_sysctl_dir[] = {
+ {1, "perfmon", NULL, 0, 0755, pfm_ctl_table, },
+ {0,},
+};
+static ctl_table pfm_sysctl_root[] = {
+ {1, "kernel", NULL, 0, 0755, pfm_sysctl_dir, },
+ {0,},
+};
+static struct ctl_table_header *pfm_sysctl_header;
+
+static int pfm_context_unload(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs);
+static int pfm_flush(struct file *filp);
+
+#define pfm_get_cpu_var(v) __ia64_per_cpu_var(v)
+#define pfm_get_cpu_data(a,b) per_cpu(a, b)
+
+static inline void
+pfm_put_task(struct task_struct *task)
+{
+ if (task != current) put_task_struct(task);
+}
+
+static inline void
+pfm_set_task_notify(struct task_struct *task)
+{
+ struct thread_info *info;
+
+ info = (struct thread_info *) ((char *) task + IA64_TASK_SIZE);
+ set_bit(TIF_NOTIFY_RESUME, &info->flags);
+}
+
+static inline void
+pfm_clear_task_notify(void)
+{
+ clear_thread_flag(TIF_NOTIFY_RESUME);
+}
+
+static inline void
+pfm_reserve_page(unsigned long a)
+{
+ SetPageReserved(vmalloc_to_page((void *)a));
+}
+static inline void
+pfm_unreserve_page(unsigned long a)
+{
+ ClearPageReserved(vmalloc_to_page((void*)a));
+}
+
+static inline unsigned long
+pfm_protect_ctx_ctxsw(pfm_context_t *x)
+{
+ spin_lock(&(x)->ctx_lock);
+ return 0UL;
+}
+
+static inline unsigned long
+pfm_unprotect_ctx_ctxsw(pfm_context_t *x, unsigned long f)
+{
+ spin_unlock(&(x)->ctx_lock);
+}
+
+static inline unsigned int
+pfm_do_munmap(struct mm_struct *mm, unsigned long addr, size_t len, int acct)
+{
+ return do_munmap(mm, addr, len);
+}
+
+static inline unsigned long
+pfm_get_unmapped_area(struct file *file, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags, unsigned long exec)
+{
+ return get_unmapped_area(file, addr, len, pgoff, flags);
+}
+
+
+static struct super_block *
+pfmfs_get_sb(struct file_system_type *fs_type, int flags, const char *dev_name, void *data)
+{
+ return get_sb_pseudo(fs_type, "pfm:", NULL, PFMFS_MAGIC);
+}
+
+static struct file_system_type pfm_fs_type = {
+ .name = "pfmfs",
+ .get_sb = pfmfs_get_sb,
+ .kill_sb = kill_anon_super,
+};
+
+DEFINE_PER_CPU(unsigned long, pfm_syst_info);
+DEFINE_PER_CPU(struct task_struct *, pmu_owner);
+DEFINE_PER_CPU(pfm_context_t *, pmu_ctx);
+DEFINE_PER_CPU(unsigned long, pmu_activation_number);
+
+
+/* forward declaration */
+static struct file_operations pfm_file_ops;
+
+/*
+ * forward declarations
+ */
+#ifndef CONFIG_SMP
+static void pfm_lazy_save_regs (struct task_struct *ta);
+#endif
+
+void dump_pmu_state(const char *);
+static int pfm_write_ibr_dbr(int mode, pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs);
+
+#include "perfmon_itanium.h"
+#include "perfmon_mckinley.h"
+#include "perfmon_generic.h"
+
+static pmu_config_t *pmu_confs[]={
+ &pmu_conf_mck,
+ &pmu_conf_ita,
+ &pmu_conf_gen, /* must be last */
+ NULL
+};
+
+
+static int pfm_end_notify_user(pfm_context_t *ctx);
+
+static inline void
+pfm_clear_psr_pp(void)
+{
+ ia64_rsm(IA64_PSR_PP);
+ ia64_srlz_i();
+}
+
+static inline void
+pfm_set_psr_pp(void)
+{
+ ia64_ssm(IA64_PSR_PP);
+ ia64_srlz_i();
+}
+
+static inline void
+pfm_clear_psr_up(void)
+{
+ ia64_rsm(IA64_PSR_UP);
+ ia64_srlz_i();
+}
+
+static inline void
+pfm_set_psr_up(void)
+{
+ ia64_ssm(IA64_PSR_UP);
+ ia64_srlz_i();
+}
+
+static inline unsigned long
+pfm_get_psr(void)
+{
+ unsigned long tmp;
+ tmp = ia64_getreg(_IA64_REG_PSR);
+ ia64_srlz_i();
+ return tmp;
+}
+
+static inline void
+pfm_set_psr_l(unsigned long val)
+{
+ ia64_setreg(_IA64_REG_PSR_L, val);
+ ia64_srlz_i();
+}
+
+static inline void
+pfm_freeze_pmu(void)
+{
+ ia64_set_pmc(0,1UL);
+ ia64_srlz_d();
+}
+
+static inline void
+pfm_unfreeze_pmu(void)
+{
+ ia64_set_pmc(0,0UL);
+ ia64_srlz_d();
+}
+
+static inline void
+pfm_restore_ibrs(unsigned long *ibrs, unsigned int nibrs)
+{
+ int i;
+
+ for (i=0; i < nibrs; i++) {
+ ia64_set_ibr(i, ibrs[i]);
+ ia64_dv_serialize_instruction();
+ }
+ ia64_srlz_i();
+}
+
+static inline void
+pfm_restore_dbrs(unsigned long *dbrs, unsigned int ndbrs)
+{
+ int i;
+
+ for (i=0; i < ndbrs; i++) {
+ ia64_set_dbr(i, dbrs[i]);
+ ia64_dv_serialize_data();
+ }
+ ia64_srlz_d();
+}
+
+/*
+ * PMD[i] must be a counter. no check is made
+ */
+static inline unsigned long
+pfm_read_soft_counter(pfm_context_t *ctx, int i)
+{
+ return ctx->ctx_pmds[i].val + (ia64_get_pmd(i) & pmu_conf->ovfl_val);
+}
+
+/*
+ * PMD[i] must be a counter. no check is made
+ */
+static inline void
+pfm_write_soft_counter(pfm_context_t *ctx, int i, unsigned long val)
+{
+ unsigned long ovfl_val = pmu_conf->ovfl_val;
+
+ ctx->ctx_pmds[i].val = val & ~ovfl_val;
+ /*
+ * writing to unimplemented part is ignore, so we do not need to
+ * mask off top part
+ */
+ ia64_set_pmd(i, val & ovfl_val);
+}
+
+static pfm_msg_t *
+pfm_get_new_msg(pfm_context_t *ctx)
+{
+ int idx, next;
+
+ next = (ctx->ctx_msgq_tail+1) % PFM_MAX_MSGS;
+
+ DPRINT(("ctx_fd=%p head=%d tail=%d\n", ctx, ctx->ctx_msgq_head, ctx->ctx_msgq_tail));
+ if (next == ctx->ctx_msgq_head) return NULL;
+
+ idx = ctx->ctx_msgq_tail;
+ ctx->ctx_msgq_tail = next;
+
+ DPRINT(("ctx=%p head=%d tail=%d msg=%d\n", ctx, ctx->ctx_msgq_head, ctx->ctx_msgq_tail, idx));
+
+ return ctx->ctx_msgq+idx;
+}
+
+static pfm_msg_t *
+pfm_get_next_msg(pfm_context_t *ctx)
+{
+ pfm_msg_t *msg;
+
+ DPRINT(("ctx=%p head=%d tail=%d\n", ctx, ctx->ctx_msgq_head, ctx->ctx_msgq_tail));
+
+ if (PFM_CTXQ_EMPTY(ctx)) return NULL;
+
+ /*
+ * get oldest message
+ */
+ msg = ctx->ctx_msgq+ctx->ctx_msgq_head;
+
+ /*
+ * and move forward
+ */
+ ctx->ctx_msgq_head = (ctx->ctx_msgq_head+1) % PFM_MAX_MSGS;
+
+ DPRINT(("ctx=%p head=%d tail=%d type=%d\n", ctx, ctx->ctx_msgq_head, ctx->ctx_msgq_tail, msg->pfm_gen_msg.msg_type));
+
+ return msg;
+}
+
+static void
+pfm_reset_msgq(pfm_context_t *ctx)
+{
+ ctx->ctx_msgq_head = ctx->ctx_msgq_tail = 0;
+ DPRINT(("ctx=%p msgq reset\n", ctx));
+}
+
+static void *
+pfm_rvmalloc(unsigned long size)
+{
+ void *mem;
+ unsigned long addr;
+
+ size = PAGE_ALIGN(size);
+ mem = vmalloc(size);
+ if (mem) {
+ //printk("perfmon: CPU%d pfm_rvmalloc(%ld)=%p\n", smp_processor_id(), size, mem);
+ memset(mem, 0, size);
+ addr = (unsigned long)mem;
+ while (size > 0) {
+ pfm_reserve_page(addr);
+ addr+=PAGE_SIZE;
+ size-=PAGE_SIZE;
+ }
+ }
+ return mem;
+}
+
+static void
+pfm_rvfree(void *mem, unsigned long size)
+{
+ unsigned long addr;
+
+ if (mem) {
+ DPRINT(("freeing physical buffer @%p size=%lu\n", mem, size));
+ addr = (unsigned long) mem;
+ while ((long) size > 0) {
+ pfm_unreserve_page(addr);
+ addr+=PAGE_SIZE;
+ size-=PAGE_SIZE;
+ }
+ vfree(mem);
+ }
+ return;
+}
+
+static pfm_context_t *
+pfm_context_alloc(void)
+{
+ pfm_context_t *ctx;
+
+ /*
+ * allocate context descriptor
+ * must be able to free with interrupts disabled
+ */
+ ctx = kmalloc(sizeof(pfm_context_t), GFP_KERNEL);
+ if (ctx) {
+ memset(ctx, 0, sizeof(pfm_context_t));
+ DPRINT(("alloc ctx @%p\n", ctx));
+ }
+ return ctx;
+}
+
+static void
+pfm_context_free(pfm_context_t *ctx)
+{
+ if (ctx) {
+ DPRINT(("free ctx @%p\n", ctx));
+ kfree(ctx);
+ }
+}
+
+static void
+pfm_mask_monitoring(struct task_struct *task)
+{
+ pfm_context_t *ctx = PFM_GET_CTX(task);
+ struct thread_struct *th = &task->thread;
+ unsigned long mask, val, ovfl_mask;
+ int i;
+
+ DPRINT_ovfl(("masking monitoring for [%d]\n", task->pid));
+
+ ovfl_mask = pmu_conf->ovfl_val;
+ /*
+ * monitoring can only be masked as a result of a valid
+ * counter overflow. In UP, it means that the PMU still
+ * has an owner. Note that the owner can be different
+ * from the current task. However the PMU state belongs
+ * to the owner.
+ * In SMP, a valid overflow only happens when task is
+ * current. Therefore if we come here, we know that
+ * the PMU state belongs to the current task, therefore
+ * we can access the live registers.
+ *
+ * So in both cases, the live register contains the owner's
+ * state. We can ONLY touch the PMU registers and NOT the PSR.
+ *
+ * As a consequence to this call, the thread->pmds[] array
+ * contains stale information which must be ignored
+ * when context is reloaded AND monitoring is active (see
+ * pfm_restart).
+ */
+ mask = ctx->ctx_used_pmds[0];
+ for (i = 0; mask; i++, mask>>=1) {
+ /* skip non used pmds */
+ if ((mask & 0x1) == 0) continue;
+ val = ia64_get_pmd(i);
+
+ if (PMD_IS_COUNTING(i)) {
+ /*
+ * we rebuild the full 64 bit value of the counter
+ */
+ ctx->ctx_pmds[i].val += (val & ovfl_mask);
+ } else {
+ ctx->ctx_pmds[i].val = val;
+ }
+ DPRINT_ovfl(("pmd[%d]=0x%lx hw_pmd=0x%lx\n",
+ i,
+ ctx->ctx_pmds[i].val,
+ val & ovfl_mask));
+ }
+ /*
+ * mask monitoring by setting the privilege level to 0
+ * we cannot use psr.pp/psr.up for this, it is controlled by
+ * the user
+ *
+ * if task is current, modify actual registers, otherwise modify
+ * thread save state, i.e., what will be restored in pfm_load_regs()
+ */
+ mask = ctx->ctx_used_monitors[0] >> PMU_FIRST_COUNTER;
+ for(i= PMU_FIRST_COUNTER; mask; i++, mask>>=1) {
+ if ((mask & 0x1) == 0UL) continue;
+ ia64_set_pmc(i, th->pmcs[i] & ~0xfUL);
+ th->pmcs[i] &= ~0xfUL;
+ DPRINT_ovfl(("pmc[%d]=0x%lx\n", i, th->pmcs[i]));
+ }
+ /*
+ * make all of this visible
+ */
+ ia64_srlz_d();
+}
+
+/*
+ * must always be done with task == current
+ *
+ * context must be in MASKED state when calling
+ */
+static void
+pfm_restore_monitoring(struct task_struct *task)
+{
+ pfm_context_t *ctx = PFM_GET_CTX(task);
+ struct thread_struct *th = &task->thread;
+ unsigned long mask, ovfl_mask;
+ unsigned long psr, val;
+ int i, is_system;
+
+ is_system = ctx->ctx_fl_system;
+ ovfl_mask = pmu_conf->ovfl_val;
+
+ if (task != current) {
+ printk(KERN_ERR "perfmon.%d: invalid task[%d] current[%d]\n", __LINE__, task->pid, current->pid);
+ return;
+ }
+ if (ctx->ctx_state != PFM_CTX_MASKED) {
+ printk(KERN_ERR "perfmon.%d: task[%d] current[%d] invalid state=%d\n", __LINE__,
+ task->pid, current->pid, ctx->ctx_state);
+ return;
+ }
+ psr = pfm_get_psr();
+ /*
+ * monitoring is masked via the PMC.
+ * As we restore their value, we do not want each counter to
+ * restart right away. We stop monitoring using the PSR,
+ * restore the PMC (and PMD) and then re-establish the psr
+ * as it was. Note that there can be no pending overflow at
+ * this point, because monitoring was MASKED.
+ *
+ * system-wide session are pinned and self-monitoring
+ */
+ if (is_system && (PFM_CPUINFO_GET() & PFM_CPUINFO_DCR_PP)) {
+ /* disable dcr pp */
+ ia64_setreg(_IA64_REG_CR_DCR, ia64_getreg(_IA64_REG_CR_DCR) & ~IA64_DCR_PP);
+ pfm_clear_psr_pp();
+ } else {
+ pfm_clear_psr_up();
+ }
+ /*
+ * first, we restore the PMD
+ */
+ mask = ctx->ctx_used_pmds[0];
+ for (i = 0; mask; i++, mask>>=1) {
+ /* skip non used pmds */
+ if ((mask & 0x1) == 0) continue;
+
+ if (PMD_IS_COUNTING(i)) {
+ /*
+ * we split the 64bit value according to
+ * counter width
+ */
+ val = ctx->ctx_pmds[i].val & ovfl_mask;
+ ctx->ctx_pmds[i].val &= ~ovfl_mask;
+ } else {
+ val = ctx->ctx_pmds[i].val;
+ }
+ ia64_set_pmd(i, val);
+
+ DPRINT(("pmd[%d]=0x%lx hw_pmd=0x%lx\n",
+ i,
+ ctx->ctx_pmds[i].val,
+ val));
+ }
+ /*
+ * restore the PMCs
+ */
+ mask = ctx->ctx_used_monitors[0] >> PMU_FIRST_COUNTER;
+ for(i= PMU_FIRST_COUNTER; mask; i++, mask>>=1) {
+ if ((mask & 0x1) == 0UL) continue;
+ th->pmcs[i] = ctx->ctx_pmcs[i];
+ ia64_set_pmc(i, th->pmcs[i]);
+ DPRINT(("[%d] pmc[%d]=0x%lx\n", task->pid, i, th->pmcs[i]));
+ }
+ ia64_srlz_d();
+
+ /*
+ * must restore DBR/IBR because could be modified while masked
+ * XXX: need to optimize
+ */
+ if (ctx->ctx_fl_using_dbreg) {
+ pfm_restore_ibrs(ctx->ctx_ibrs, pmu_conf->num_ibrs);
+ pfm_restore_dbrs(ctx->ctx_dbrs, pmu_conf->num_dbrs);
+ }
+
+ /*
+ * now restore PSR
+ */
+ if (is_system && (PFM_CPUINFO_GET() & PFM_CPUINFO_DCR_PP)) {
+ /* enable dcr pp */
+ ia64_setreg(_IA64_REG_CR_DCR, ia64_getreg(_IA64_REG_CR_DCR) | IA64_DCR_PP);
+ ia64_srlz_i();
+ }
+ pfm_set_psr_l(psr);
+}
+
+static inline void
+pfm_save_pmds(unsigned long *pmds, unsigned long mask)
+{
+ int i;
+
+ ia64_srlz_d();
+
+ for (i=0; mask; i++, mask>>=1) {
+ if (mask & 0x1) pmds[i] = ia64_get_pmd(i);
+ }
+}
+
+/*
+ * reload from thread state (used for ctxw only)
+ */
+static inline void
+pfm_restore_pmds(unsigned long *pmds, unsigned long mask)
+{
+ int i;
+ unsigned long val, ovfl_val = pmu_conf->ovfl_val;
+
+ for (i=0; mask; i++, mask>>=1) {
+ if ((mask & 0x1) == 0) continue;
+ val = PMD_IS_COUNTING(i) ? pmds[i] & ovfl_val : pmds[i];
+ ia64_set_pmd(i, val);
+ }
+ ia64_srlz_d();
+}
+
+/*
+ * propagate PMD from context to thread-state
+ */
+static inline void
+pfm_copy_pmds(struct task_struct *task, pfm_context_t *ctx)
+{
+ struct thread_struct *thread = &task->thread;
+ unsigned long ovfl_val = pmu_conf->ovfl_val;
+ unsigned long mask = ctx->ctx_all_pmds[0];
+ unsigned long val;
+ int i;
+
+ DPRINT(("mask=0x%lx\n", mask));
+
+ for (i=0; mask; i++, mask>>=1) {
+
+ val = ctx->ctx_pmds[i].val;
+
+ /*
+ * We break up the 64 bit value into 2 pieces
+ * the lower bits go to the machine state in the
+ * thread (will be reloaded on ctxsw in).
+ * The upper part stays in the soft-counter.
+ */
+ if (PMD_IS_COUNTING(i)) {
+ ctx->ctx_pmds[i].val = val & ~ovfl_val;
+ val &= ovfl_val;
+ }
+ thread->pmds[i] = val;
+
+ DPRINT(("pmd[%d]=0x%lx soft_val=0x%lx\n",
+ i,
+ thread->pmds[i],
+ ctx->ctx_pmds[i].val));
+ }
+}
+
+/*
+ * propagate PMC from context to thread-state
+ */
+static inline void
+pfm_copy_pmcs(struct task_struct *task, pfm_context_t *ctx)
+{
+ struct thread_struct *thread = &task->thread;
+ unsigned long mask = ctx->ctx_all_pmcs[0];
+ int i;
+
+ DPRINT(("mask=0x%lx\n", mask));
+
+ for (i=0; mask; i++, mask>>=1) {
+ /* masking 0 with ovfl_val yields 0 */
+ thread->pmcs[i] = ctx->ctx_pmcs[i];
+ DPRINT(("pmc[%d]=0x%lx\n", i, thread->pmcs[i]));
+ }
+}
+
+
+
+static inline void
+pfm_restore_pmcs(unsigned long *pmcs, unsigned long mask)
+{
+ int i;
+
+ for (i=0; mask; i++, mask>>=1) {
+ if ((mask & 0x1) == 0) continue;
+ ia64_set_pmc(i, pmcs[i]);
+ }
+ ia64_srlz_d();
+}
+
+static inline int
+pfm_uuid_cmp(pfm_uuid_t a, pfm_uuid_t b)
+{
+ return memcmp(a, b, sizeof(pfm_uuid_t));
+}
+
+static inline int
+pfm_buf_fmt_exit(pfm_buffer_fmt_t *fmt, struct task_struct *task, void *buf, struct pt_regs *regs)
+{
+ int ret = 0;
+ if (fmt->fmt_exit) ret = (*fmt->fmt_exit)(task, buf, regs);
+ return ret;
+}
+
+static inline int
+pfm_buf_fmt_getsize(pfm_buffer_fmt_t *fmt, struct task_struct *task, unsigned int flags, int cpu, void *arg, unsigned long *size)
+{
+ int ret = 0;
+ if (fmt->fmt_getsize) ret = (*fmt->fmt_getsize)(task, flags, cpu, arg, size);
+ return ret;
+}
+
+
+static inline int
+pfm_buf_fmt_validate(pfm_buffer_fmt_t *fmt, struct task_struct *task, unsigned int flags,
+ int cpu, void *arg)
+{
+ int ret = 0;
+ if (fmt->fmt_validate) ret = (*fmt->fmt_validate)(task, flags, cpu, arg);
+ return ret;
+}
+
+static inline int
+pfm_buf_fmt_init(pfm_buffer_fmt_t *fmt, struct task_struct *task, void *buf, unsigned int flags,
+ int cpu, void *arg)
+{
+ int ret = 0;
+ if (fmt->fmt_init) ret = (*fmt->fmt_init)(task, buf, flags, cpu, arg);
+ return ret;
+}
+
+static inline int
+pfm_buf_fmt_restart(pfm_buffer_fmt_t *fmt, struct task_struct *task, pfm_ovfl_ctrl_t *ctrl, void *buf, struct pt_regs *regs)
+{
+ int ret = 0;
+ if (fmt->fmt_restart) ret = (*fmt->fmt_restart)(task, ctrl, buf, regs);
+ return ret;
+}
+
+static inline int
+pfm_buf_fmt_restart_active(pfm_buffer_fmt_t *fmt, struct task_struct *task, pfm_ovfl_ctrl_t *ctrl, void *buf, struct pt_regs *regs)
+{
+ int ret = 0;
+ if (fmt->fmt_restart_active) ret = (*fmt->fmt_restart_active)(task, ctrl, buf, regs);
+ return ret;
+}
+
+static pfm_buffer_fmt_t *
+__pfm_find_buffer_fmt(pfm_uuid_t uuid)
+{
+ struct list_head * pos;
+ pfm_buffer_fmt_t * entry;
+
+ list_for_each(pos, &pfm_buffer_fmt_list) {
+ entry = list_entry(pos, pfm_buffer_fmt_t, fmt_list);
+ if (pfm_uuid_cmp(uuid, entry->fmt_uuid) == 0)
+ return entry;
+ }
+ return NULL;
+}
+
+/*
+ * find a buffer format based on its uuid
+ */
+static pfm_buffer_fmt_t *
+pfm_find_buffer_fmt(pfm_uuid_t uuid)
+{
+ pfm_buffer_fmt_t * fmt;
+ spin_lock(&pfm_buffer_fmt_lock);
+ fmt = __pfm_find_buffer_fmt(uuid);
+ spin_unlock(&pfm_buffer_fmt_lock);
+ return fmt;
+}
+
+int
+pfm_register_buffer_fmt(pfm_buffer_fmt_t *fmt)
+{
+ int ret = 0;
+
+ /* some sanity checks */
+ if (fmt == NULL || fmt->fmt_name == NULL) return -EINVAL;
+
+ /* we need at least a handler */
+ if (fmt->fmt_handler == NULL) return -EINVAL;
+
+ /*
+ * XXX: need check validity of fmt_arg_size
+ */
+
+ spin_lock(&pfm_buffer_fmt_lock);
+
+ if (__pfm_find_buffer_fmt(fmt->fmt_uuid)) {
+ printk(KERN_ERR "perfmon: duplicate sampling format: %s\n", fmt->fmt_name);
+ ret = -EBUSY;
+ goto out;
+ }
+ list_add(&fmt->fmt_list, &pfm_buffer_fmt_list);
+ printk(KERN_INFO "perfmon: added sampling format %s\n", fmt->fmt_name);
+
+out:
+ spin_unlock(&pfm_buffer_fmt_lock);
+ return ret;
+}
+EXPORT_SYMBOL(pfm_register_buffer_fmt);
+
+int
+pfm_unregister_buffer_fmt(pfm_uuid_t uuid)
+{
+ pfm_buffer_fmt_t *fmt;
+ int ret = 0;
+
+ spin_lock(&pfm_buffer_fmt_lock);
+
+ fmt = __pfm_find_buffer_fmt(uuid);
+ if (!fmt) {
+ printk(KERN_ERR "perfmon: cannot unregister format, not found\n");
+ ret = -EINVAL;
+ goto out;
+ }
+ list_del_init(&fmt->fmt_list);
+ printk(KERN_INFO "perfmon: removed sampling format: %s\n", fmt->fmt_name);
+
+out:
+ spin_unlock(&pfm_buffer_fmt_lock);
+ return ret;
+
+}
+EXPORT_SYMBOL(pfm_unregister_buffer_fmt);
+
+static int
+pfm_reserve_session(struct task_struct *task, int is_syswide, unsigned int cpu)
+{
+ unsigned long flags;
+ /*
+ * validy checks on cpu_mask have been done upstream
+ */
+ LOCK_PFS(flags);
+
+ DPRINT(("in sys_sessions=%u task_sessions=%u dbregs=%u syswide=%d cpu=%u\n",
+ pfm_sessions.pfs_sys_sessions,
+ pfm_sessions.pfs_task_sessions,
+ pfm_sessions.pfs_sys_use_dbregs,
+ is_syswide,
+ cpu));
+
+ if (is_syswide) {
+ /*
+ * cannot mix system wide and per-task sessions
+ */
+ if (pfm_sessions.pfs_task_sessions > 0UL) {
+ DPRINT(("system wide not possible, %u conflicting task_sessions\n",
+ pfm_sessions.pfs_task_sessions));
+ goto abort;
+ }
+
+ if (pfm_sessions.pfs_sys_session[cpu]) goto error_conflict;
+
+ DPRINT(("reserving system wide session on CPU%u currently on CPU%u\n", cpu, smp_processor_id()));
+
+ pfm_sessions.pfs_sys_session[cpu] = task;
+
+ pfm_sessions.pfs_sys_sessions++ ;
+
+ } else {
+ if (pfm_sessions.pfs_sys_sessions) goto abort;
+ pfm_sessions.pfs_task_sessions++;
+ }
+
+ DPRINT(("out sys_sessions=%u task_sessions=%u dbregs=%u syswide=%d cpu=%u\n",
+ pfm_sessions.pfs_sys_sessions,
+ pfm_sessions.pfs_task_sessions,
+ pfm_sessions.pfs_sys_use_dbregs,
+ is_syswide,
+ cpu));
+
+ UNLOCK_PFS(flags);
+
+ return 0;
+
+error_conflict:
+ DPRINT(("system wide not possible, conflicting session [%d] on CPU%d\n",
+ pfm_sessions.pfs_sys_session[cpu]->pid,
+ smp_processor_id()));
+abort:
+ UNLOCK_PFS(flags);
+
+ return -EBUSY;
+
+}
+
+static int
+pfm_unreserve_session(pfm_context_t *ctx, int is_syswide, unsigned int cpu)
+{
+ unsigned long flags;
+ /*
+ * validy checks on cpu_mask have been done upstream
+ */
+ LOCK_PFS(flags);
+
+ DPRINT(("in sys_sessions=%u task_sessions=%u dbregs=%u syswide=%d cpu=%u\n",
+ pfm_sessions.pfs_sys_sessions,
+ pfm_sessions.pfs_task_sessions,
+ pfm_sessions.pfs_sys_use_dbregs,
+ is_syswide,
+ cpu));
+
+
+ if (is_syswide) {
+ pfm_sessions.pfs_sys_session[cpu] = NULL;
+ /*
+ * would not work with perfmon+more than one bit in cpu_mask
+ */
+ if (ctx && ctx->ctx_fl_using_dbreg) {
+ if (pfm_sessions.pfs_sys_use_dbregs == 0) {
+ printk(KERN_ERR "perfmon: invalid release for ctx %p sys_use_dbregs=0\n", ctx);
+ } else {
+ pfm_sessions.pfs_sys_use_dbregs--;
+ }
+ }
+ pfm_sessions.pfs_sys_sessions--;
+ } else {
+ pfm_sessions.pfs_task_sessions--;
+ }
+ DPRINT(("out sys_sessions=%u task_sessions=%u dbregs=%u syswide=%d cpu=%u\n",
+ pfm_sessions.pfs_sys_sessions,
+ pfm_sessions.pfs_task_sessions,
+ pfm_sessions.pfs_sys_use_dbregs,
+ is_syswide,
+ cpu));
+
+ UNLOCK_PFS(flags);
+
+ return 0;
+}
+
+/*
+ * removes virtual mapping of the sampling buffer.
+ * IMPORTANT: cannot be called with interrupts disable, e.g. inside
+ * a PROTECT_CTX() section.
+ */
+static int
+pfm_remove_smpl_mapping(struct task_struct *task, void *vaddr, unsigned long size)
+{
+ int r;
+
+ /* sanity checks */
+ if (task->mm == NULL || size == 0UL || vaddr == NULL) {
+ printk(KERN_ERR "perfmon: pfm_remove_smpl_mapping [%d] invalid context mm=%p\n", task->pid, task->mm);
+ return -EINVAL;
+ }
+
+ DPRINT(("smpl_vaddr=%p size=%lu\n", vaddr, size));
+
+ /*
+ * does the actual unmapping
+ */
+ down_write(&task->mm->mmap_sem);
+
+ DPRINT(("down_write done smpl_vaddr=%p size=%lu\n", vaddr, size));
+
+ r = pfm_do_munmap(task->mm, (unsigned long)vaddr, size, 0);
+
+ up_write(&task->mm->mmap_sem);
+ if (r !=0) {
+ printk(KERN_ERR "perfmon: [%d] unable to unmap sampling buffer @%p size=%lu\n", task->pid, vaddr, size);
+ }
+
+ DPRINT(("do_unmap(%p, %lu)=%d\n", vaddr, size, r));
+
+ return 0;
+}
+
+/*
+ * free actual physical storage used by sampling buffer
+ */
+#if 0
+static int
+pfm_free_smpl_buffer(pfm_context_t *ctx)
+{
+ pfm_buffer_fmt_t *fmt;
+
+ if (ctx->ctx_smpl_hdr == NULL) goto invalid_free;
+
+ /*
+ * we won't use the buffer format anymore
+ */
+ fmt = ctx->ctx_buf_fmt;
+
+ DPRINT(("sampling buffer @%p size %lu vaddr=%p\n",
+ ctx->ctx_smpl_hdr,
+ ctx->ctx_smpl_size,
+ ctx->ctx_smpl_vaddr));
+
+ pfm_buf_fmt_exit(fmt, current, NULL, NULL);
+
+ /*
+ * free the buffer
+ */
+ pfm_rvfree(ctx->ctx_smpl_hdr, ctx->ctx_smpl_size);
+
+ ctx->ctx_smpl_hdr = NULL;
+ ctx->ctx_smpl_size = 0UL;
+
+ return 0;
+
+invalid_free:
+ printk(KERN_ERR "perfmon: pfm_free_smpl_buffer [%d] no buffer\n", current->pid);
+ return -EINVAL;
+}
+#endif
+
+static inline void
+pfm_exit_smpl_buffer(pfm_buffer_fmt_t *fmt)
+{
+ if (fmt == NULL) return;
+
+ pfm_buf_fmt_exit(fmt, current, NULL, NULL);
+
+}
+
+/*
+ * pfmfs should _never_ be mounted by userland - too much of security hassle,
+ * no real gain from having the whole whorehouse mounted. So we don't need
+ * any operations on the root directory. However, we need a non-trivial
+ * d_name - pfm: will go nicely and kill the special-casing in procfs.
+ */
+static struct vfsmount *pfmfs_mnt;
+
+static int __init
+init_pfm_fs(void)
+{
+ int err = register_filesystem(&pfm_fs_type);
+ if (!err) {
+ pfmfs_mnt = kern_mount(&pfm_fs_type);
+ err = PTR_ERR(pfmfs_mnt);
+ if (IS_ERR(pfmfs_mnt))
+ unregister_filesystem(&pfm_fs_type);
+ else
+ err = 0;
+ }
+ return err;
+}
+
+static void __exit
+exit_pfm_fs(void)
+{
+ unregister_filesystem(&pfm_fs_type);
+ mntput(pfmfs_mnt);
+}
+
+static ssize_t
+pfm_read(struct file *filp, char __user *buf, size_t size, loff_t *ppos)
+{
+ pfm_context_t *ctx;
+ pfm_msg_t *msg;
+ ssize_t ret;
+ unsigned long flags;
+ DECLARE_WAITQUEUE(wait, current);
+ if (PFM_IS_FILE(filp) == 0) {
+ printk(KERN_ERR "perfmon: pfm_poll: bad magic [%d]\n", current->pid);
+ return -EINVAL;
+ }
+
+ ctx = (pfm_context_t *)filp->private_data;
+ if (ctx == NULL) {
+ printk(KERN_ERR "perfmon: pfm_read: NULL ctx [%d]\n", current->pid);
+ return -EINVAL;
+ }
+
+ /*
+ * check even when there is no message
+ */
+ if (size < sizeof(pfm_msg_t)) {
+ DPRINT(("message is too small ctx=%p (>=%ld)\n", ctx, sizeof(pfm_msg_t)));
+ return -EINVAL;
+ }
+
+ PROTECT_CTX(ctx, flags);
+
+ /*
+ * put ourselves on the wait queue
+ */
+ add_wait_queue(&ctx->ctx_msgq_wait, &wait);
+
+
+ for(;;) {
+ /*
+ * check wait queue
+ */
+
+ set_current_state(TASK_INTERRUPTIBLE);
+
+ DPRINT(("head=%d tail=%d\n", ctx->ctx_msgq_head, ctx->ctx_msgq_tail));
+
+ ret = 0;
+ if(PFM_CTXQ_EMPTY(ctx) == 0) break;
+
+ UNPROTECT_CTX(ctx, flags);
+
+ /*
+ * check non-blocking read
+ */
+ ret = -EAGAIN;
+ if(filp->f_flags & O_NONBLOCK) break;
+
+ /*
+ * check pending signals
+ */
+ if(signal_pending(current)) {
+ ret = -EINTR;
+ break;
+ }
+ /*
+ * no message, so wait
+ */
+ schedule();
+
+ PROTECT_CTX(ctx, flags);
+ }
+ DPRINT(("[%d] back to running ret=%ld\n", current->pid, ret));
+ set_current_state(TASK_RUNNING);
+ remove_wait_queue(&ctx->ctx_msgq_wait, &wait);
+
+ if (ret < 0) goto abort;
+
+ ret = -EINVAL;
+ msg = pfm_get_next_msg(ctx);
+ if (msg == NULL) {
+ printk(KERN_ERR "perfmon: pfm_read no msg for ctx=%p [%d]\n", ctx, current->pid);
+ goto abort_locked;
+ }
+
+ DPRINT(("[%d] fd=%d type=%d\n", current->pid, msg->pfm_gen_msg.msg_ctx_fd, msg->pfm_gen_msg.msg_type));
+
+ ret = -EFAULT;
+ if(copy_to_user(buf, msg, sizeof(pfm_msg_t)) == 0) ret = sizeof(pfm_msg_t);
+
+abort_locked:
+ UNPROTECT_CTX(ctx, flags);
+abort:
+ return ret;
+}
+
+static ssize_t
+pfm_write(struct file *file, const char __user *ubuf,
+ size_t size, loff_t *ppos)
+{
+ DPRINT(("pfm_write called\n"));
+ return -EINVAL;
+}
+
+static unsigned int
+pfm_poll(struct file *filp, poll_table * wait)
+{
+ pfm_context_t *ctx;
+ unsigned long flags;
+ unsigned int mask = 0;
+
+ if (PFM_IS_FILE(filp) == 0) {
+ printk(KERN_ERR "perfmon: pfm_poll: bad magic [%d]\n", current->pid);
+ return 0;
+ }
+
+ ctx = (pfm_context_t *)filp->private_data;
+ if (ctx == NULL) {
+ printk(KERN_ERR "perfmon: pfm_poll: NULL ctx [%d]\n", current->pid);
+ return 0;
+ }
+
+
+ DPRINT(("pfm_poll ctx_fd=%d before poll_wait\n", ctx->ctx_fd));
+
+ poll_wait(filp, &ctx->ctx_msgq_wait, wait);
+
+ PROTECT_CTX(ctx, flags);
+
+ if (PFM_CTXQ_EMPTY(ctx) == 0)
+ mask = POLLIN | POLLRDNORM;
+
+ UNPROTECT_CTX(ctx, flags);
+
+ DPRINT(("pfm_poll ctx_fd=%d mask=0x%x\n", ctx->ctx_fd, mask));
+
+ return mask;
+}
+
+static int
+pfm_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
+{
+ DPRINT(("pfm_ioctl called\n"));
+ return -EINVAL;
+}
+
+/*
+ * interrupt cannot be masked when coming here
+ */
+static inline int
+pfm_do_fasync(int fd, struct file *filp, pfm_context_t *ctx, int on)
+{
+ int ret;
+
+ ret = fasync_helper (fd, filp, on, &ctx->ctx_async_queue);
+
+ DPRINT(("pfm_fasync called by [%d] on ctx_fd=%d on=%d async_queue=%p ret=%d\n",
+ current->pid,
+ fd,
+ on,
+ ctx->ctx_async_queue, ret));
+
+ return ret;
+}
+
+static int
+pfm_fasync(int fd, struct file *filp, int on)
+{
+ pfm_context_t *ctx;
+ int ret;
+
+ if (PFM_IS_FILE(filp) == 0) {
+ printk(KERN_ERR "perfmon: pfm_fasync bad magic [%d]\n", current->pid);
+ return -EBADF;
+ }
+
+ ctx = (pfm_context_t *)filp->private_data;
+ if (ctx == NULL) {
+ printk(KERN_ERR "perfmon: pfm_fasync NULL ctx [%d]\n", current->pid);
+ return -EBADF;
+ }
+ /*
+ * we cannot mask interrupts during this call because this may
+ * may go to sleep if memory is not readily avalaible.
+ *
+ * We are protected from the conetxt disappearing by the get_fd()/put_fd()
+ * done in caller. Serialization of this function is ensured by caller.
+ */
+ ret = pfm_do_fasync(fd, filp, ctx, on);
+
+
+ DPRINT(("pfm_fasync called on ctx_fd=%d on=%d async_queue=%p ret=%d\n",
+ fd,
+ on,
+ ctx->ctx_async_queue, ret));
+
+ return ret;
+}
+
+#ifdef CONFIG_SMP
+/*
+ * this function is exclusively called from pfm_close().
+ * The context is not protected at that time, nor are interrupts
+ * on the remote CPU. That's necessary to avoid deadlocks.
+ */
+static void
+pfm_syswide_force_stop(void *info)
+{
+ pfm_context_t *ctx = (pfm_context_t *)info;
+ struct pt_regs *regs = ia64_task_regs(current);
+ struct task_struct *owner;
+ unsigned long flags;
+ int ret;
+
+ if (ctx->ctx_cpu != smp_processor_id()) {
+ printk(KERN_ERR "perfmon: pfm_syswide_force_stop for CPU%d but on CPU%d\n",
+ ctx->ctx_cpu,
+ smp_processor_id());
+ return;
+ }
+ owner = GET_PMU_OWNER();
+ if (owner != ctx->ctx_task) {
+ printk(KERN_ERR "perfmon: pfm_syswide_force_stop CPU%d unexpected owner [%d] instead of [%d]\n",
+ smp_processor_id(),
+ owner->pid, ctx->ctx_task->pid);
+ return;
+ }
+ if (GET_PMU_CTX() != ctx) {
+ printk(KERN_ERR "perfmon: pfm_syswide_force_stop CPU%d unexpected ctx %p instead of %p\n",
+ smp_processor_id(),
+ GET_PMU_CTX(), ctx);
+ return;
+ }
+
+ DPRINT(("on CPU%d forcing system wide stop for [%d]\n", smp_processor_id(), ctx->ctx_task->pid));
+ /*
+ * the context is already protected in pfm_close(), we simply
+ * need to mask interrupts to avoid a PMU interrupt race on
+ * this CPU
+ */
+ local_irq_save(flags);
+
+ ret = pfm_context_unload(ctx, NULL, 0, regs);
+ if (ret) {
+ DPRINT(("context_unload returned %d\n", ret));
+ }
+
+ /*
+ * unmask interrupts, PMU interrupts are now spurious here
+ */
+ local_irq_restore(flags);
+}
+
+static void
+pfm_syswide_cleanup_other_cpu(pfm_context_t *ctx)
+{
+ int ret;
+
+ DPRINT(("calling CPU%d for cleanup\n", ctx->ctx_cpu));
+ ret = smp_call_function_single(ctx->ctx_cpu, pfm_syswide_force_stop, ctx, 0, 1);
+ DPRINT(("called CPU%d for cleanup ret=%d\n", ctx->ctx_cpu, ret));
+}
+#endif /* CONFIG_SMP */
+
+/*
+ * called for each close(). Partially free resources.
+ * When caller is self-monitoring, the context is unloaded.
+ */
+static int
+pfm_flush(struct file *filp)
+{
+ pfm_context_t *ctx;
+ struct task_struct *task;
+ struct pt_regs *regs;
+ unsigned long flags;
+ unsigned long smpl_buf_size = 0UL;
+ void *smpl_buf_vaddr = NULL;
+ int state, is_system;
+
+ if (PFM_IS_FILE(filp) == 0) {
+ DPRINT(("bad magic for\n"));
+ return -EBADF;
+ }
+
+ ctx = (pfm_context_t *)filp->private_data;
+ if (ctx == NULL) {
+ printk(KERN_ERR "perfmon: pfm_flush: NULL ctx [%d]\n", current->pid);
+ return -EBADF;
+ }
+
+ /*
+ * remove our file from the async queue, if we use this mode.
+ * This can be done without the context being protected. We come
+ * here when the context has become unreacheable by other tasks.
+ *
+ * We may still have active monitoring at this point and we may
+ * end up in pfm_overflow_handler(). However, fasync_helper()
+ * operates with interrupts disabled and it cleans up the
+ * queue. If the PMU handler is called prior to entering
+ * fasync_helper() then it will send a signal. If it is
+ * invoked after, it will find an empty queue and no
+ * signal will be sent. In both case, we are safe
+ */
+ if (filp->f_flags & FASYNC) {
+ DPRINT(("cleaning up async_queue=%p\n", ctx->ctx_async_queue));
+ pfm_do_fasync (-1, filp, ctx, 0);
+ }
+
+ PROTECT_CTX(ctx, flags);
+
+ state = ctx->ctx_state;
+ is_system = ctx->ctx_fl_system;
+
+ task = PFM_CTX_TASK(ctx);
+ regs = ia64_task_regs(task);
+
+ DPRINT(("ctx_state=%d is_current=%d\n",
+ state,
+ task == current ? 1 : 0));
+
+ /*
+ * if state == UNLOADED, then task is NULL
+ */
+
+ /*
+ * we must stop and unload because we are losing access to the context.
+ */
+ if (task == current) {
+#ifdef CONFIG_SMP
+ /*
+ * the task IS the owner but it migrated to another CPU: that's bad
+ * but we must handle this cleanly. Unfortunately, the kernel does
+ * not provide a mechanism to block migration (while the context is loaded).
+ *
+ * We need to release the resource on the ORIGINAL cpu.
+ */
+ if (is_system && ctx->ctx_cpu != smp_processor_id()) {
+
+ DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu));
+ /*
+ * keep context protected but unmask interrupt for IPI
+ */
+ local_irq_restore(flags);
+
+ pfm_syswide_cleanup_other_cpu(ctx);
+
+ /*
+ * restore interrupt masking
+ */
+ local_irq_save(flags);
+
+ /*
+ * context is unloaded at this point
+ */
+ } else
+#endif /* CONFIG_SMP */
+ {
+
+ DPRINT(("forcing unload\n"));
+ /*
+ * stop and unload, returning with state UNLOADED
+ * and session unreserved.
+ */
+ pfm_context_unload(ctx, NULL, 0, regs);
+
+ DPRINT(("ctx_state=%d\n", ctx->ctx_state));
+ }
+ }
+
+ /*
+ * remove virtual mapping, if any, for the calling task.
+ * cannot reset ctx field until last user is calling close().
+ *
+ * ctx_smpl_vaddr must never be cleared because it is needed
+ * by every task with access to the context
+ *
+ * When called from do_exit(), the mm context is gone already, therefore
+ * mm is NULL, i.e., the VMA is already gone and we do not have to
+ * do anything here
+ */
+ if (ctx->ctx_smpl_vaddr && current->mm) {
+ smpl_buf_vaddr = ctx->ctx_smpl_vaddr;
+ smpl_buf_size = ctx->ctx_smpl_size;
+ }
+
+ UNPROTECT_CTX(ctx, flags);
+
+ /*
+ * if there was a mapping, then we systematically remove it
+ * at this point. Cannot be done inside critical section
+ * because some VM function reenables interrupts.
+ *
+ */
+ if (smpl_buf_vaddr) pfm_remove_smpl_mapping(current, smpl_buf_vaddr, smpl_buf_size);
+
+ return 0;
+}
+/*
+ * called either on explicit close() or from exit_files().
+ * Only the LAST user of the file gets to this point, i.e., it is
+ * called only ONCE.
+ *
+ * IMPORTANT: we get called ONLY when the refcnt on the file gets to zero
+ * (fput()),i.e, last task to access the file. Nobody else can access the
+ * file at this point.
+ *
+ * When called from exit_files(), the VMA has been freed because exit_mm()
+ * is executed before exit_files().
+ *
+ * When called from exit_files(), the current task is not yet ZOMBIE but we
+ * flush the PMU state to the context.
+ */
+static int
+pfm_close(struct inode *inode, struct file *filp)
+{
+ pfm_context_t *ctx;
+ struct task_struct *task;
+ struct pt_regs *regs;
+ DECLARE_WAITQUEUE(wait, current);
+ unsigned long flags;
+ unsigned long smpl_buf_size = 0UL;
+ void *smpl_buf_addr = NULL;
+ int free_possible = 1;
+ int state, is_system;
+
+ DPRINT(("pfm_close called private=%p\n", filp->private_data));
+
+ if (PFM_IS_FILE(filp) == 0) {
+ DPRINT(("bad magic\n"));
+ return -EBADF;
+ }
+
+ ctx = (pfm_context_t *)filp->private_data;
+ if (ctx == NULL) {
+ printk(KERN_ERR "perfmon: pfm_close: NULL ctx [%d]\n", current->pid);
+ return -EBADF;
+ }
+
+ PROTECT_CTX(ctx, flags);
+
+ state = ctx->ctx_state;
+ is_system = ctx->ctx_fl_system;
+
+ task = PFM_CTX_TASK(ctx);
+ regs = ia64_task_regs(task);
+
+ DPRINT(("ctx_state=%d is_current=%d\n",
+ state,
+ task == current ? 1 : 0));
+
+ /*
+ * if task == current, then pfm_flush() unloaded the context
+ */
+ if (state == PFM_CTX_UNLOADED) goto doit;
+
+ /*
+ * context is loaded/masked and task != current, we need to
+ * either force an unload or go zombie
+ */
+
+ /*
+ * The task is currently blocked or will block after an overflow.
+ * we must force it to wakeup to get out of the
+ * MASKED state and transition to the unloaded state by itself.
+ *
+ * This situation is only possible for per-task mode
+ */
+ if (state == PFM_CTX_MASKED && CTX_OVFL_NOBLOCK(ctx) == 0) {
+
+ /*
+ * set a "partial" zombie state to be checked
+ * upon return from down() in pfm_handle_work().
+ *
+ * We cannot use the ZOMBIE state, because it is checked
+ * by pfm_load_regs() which is called upon wakeup from down().
+ * In such case, it would free the context and then we would
+ * return to pfm_handle_work() which would access the
+ * stale context. Instead, we set a flag invisible to pfm_load_regs()
+ * but visible to pfm_handle_work().
+ *
+ * For some window of time, we have a zombie context with
+ * ctx_state = MASKED and not ZOMBIE
+ */
+ ctx->ctx_fl_going_zombie = 1;
+
+ /*
+ * force task to wake up from MASKED state
+ */
+ up(&ctx->ctx_restart_sem);
+
+ DPRINT(("waking up ctx_state=%d\n", state));
+
+ /*
+ * put ourself to sleep waiting for the other
+ * task to report completion
+ *
+ * the context is protected by mutex, therefore there
+ * is no risk of being notified of completion before
+ * begin actually on the waitq.
+ */
+ set_current_state(TASK_INTERRUPTIBLE);
+ add_wait_queue(&ctx->ctx_zombieq, &wait);
+
+ UNPROTECT_CTX(ctx, flags);
+
+ /*
+ * XXX: check for signals :
+ * - ok for explicit close
+ * - not ok when coming from exit_files()
+ */
+ schedule();
+
+
+ PROTECT_CTX(ctx, flags);
+
+
+ remove_wait_queue(&ctx->ctx_zombieq, &wait);
+ set_current_state(TASK_RUNNING);
+
+ /*
+ * context is unloaded at this point
+ */
+ DPRINT(("after zombie wakeup ctx_state=%d for\n", state));
+ }
+ else if (task != current) {
+#ifdef CONFIG_SMP
+ /*
+ * switch context to zombie state
+ */
+ ctx->ctx_state = PFM_CTX_ZOMBIE;
+
+ DPRINT(("zombie ctx for [%d]\n", task->pid));
+ /*
+ * cannot free the context on the spot. deferred until
+ * the task notices the ZOMBIE state
+ */
+ free_possible = 0;
+#else
+ pfm_context_unload(ctx, NULL, 0, regs);
+#endif
+ }
+
+doit:
+ /* reload state, may have changed during opening of critical section */
+ state = ctx->ctx_state;
+
+ /*
+ * the context is still attached to a task (possibly current)
+ * we cannot destroy it right now
+ */
+
+ /*
+ * we must free the sampling buffer right here because
+ * we cannot rely on it being cleaned up later by the
+ * monitored task. It is not possible to free vmalloc'ed
+ * memory in pfm_load_regs(). Instead, we remove the buffer
+ * now. should there be subsequent PMU overflow originally
+ * meant for sampling, the will be converted to spurious
+ * and that's fine because the monitoring tools is gone anyway.
+ */
+ if (ctx->ctx_smpl_hdr) {
+ smpl_buf_addr = ctx->ctx_smpl_hdr;
+ smpl_buf_size = ctx->ctx_smpl_size;
+ /* no more sampling */
+ ctx->ctx_smpl_hdr = NULL;
+ ctx->ctx_fl_is_sampling = 0;
+ }
+
+ DPRINT(("ctx_state=%d free_possible=%d addr=%p size=%lu\n",
+ state,
+ free_possible,
+ smpl_buf_addr,
+ smpl_buf_size));
+
+ if (smpl_buf_addr) pfm_exit_smpl_buffer(ctx->ctx_buf_fmt);
+
+ /*
+ * UNLOADED that the session has already been unreserved.
+ */
+ if (state == PFM_CTX_ZOMBIE) {
+ pfm_unreserve_session(ctx, ctx->ctx_fl_system , ctx->ctx_cpu);
+ }
+
+ /*
+ * disconnect file descriptor from context must be done
+ * before we unlock.
+ */
+ filp->private_data = NULL;
+
+ /*
+ * if we free on the spot, the context is now completely unreacheable
+ * from the callers side. The monitored task side is also cut, so we
+ * can freely cut.
+ *
+ * If we have a deferred free, only the caller side is disconnected.
+ */
+ UNPROTECT_CTX(ctx, flags);
+
+ /*
+ * All memory free operations (especially for vmalloc'ed memory)
+ * MUST be done with interrupts ENABLED.
+ */
+ if (smpl_buf_addr) pfm_rvfree(smpl_buf_addr, smpl_buf_size);
+
+ /*
+ * return the memory used by the context
+ */
+ if (free_possible) pfm_context_free(ctx);
+
+ return 0;
+}
+
+static int
+pfm_no_open(struct inode *irrelevant, struct file *dontcare)
+{
+ DPRINT(("pfm_no_open called\n"));
+ return -ENXIO;
+}
+
+
+
+static struct file_operations pfm_file_ops = {
+ .llseek = no_llseek,
+ .read = pfm_read,
+ .write = pfm_write,
+ .poll = pfm_poll,
+ .ioctl = pfm_ioctl,
+ .open = pfm_no_open, /* special open code to disallow open via /proc */
+ .fasync = pfm_fasync,
+ .release = pfm_close,
+ .flush = pfm_flush
+};
+
+static int
+pfmfs_delete_dentry(struct dentry *dentry)
+{
+ return 1;
+}
+
+static struct dentry_operations pfmfs_dentry_operations = {
+ .d_delete = pfmfs_delete_dentry,
+};
+
+
+static int
+pfm_alloc_fd(struct file **cfile)
+{
+ int fd, ret = 0;
+ struct file *file = NULL;
+ struct inode * inode;
+ char name[32];
+ struct qstr this;
+
+ fd = get_unused_fd();
+ if (fd < 0) return -ENFILE;
+
+ ret = -ENFILE;
+
+ file = get_empty_filp();
+ if (!file) goto out;
+
+ /*
+ * allocate a new inode
+ */
+ inode = new_inode(pfmfs_mnt->mnt_sb);
+ if (!inode) goto out;
+
+ DPRINT(("new inode ino=%ld @%p\n", inode->i_ino, inode));
+
+ inode->i_mode = S_IFCHR|S_IRUGO;
+ inode->i_uid = current->fsuid;
+ inode->i_gid = current->fsgid;
+
+ sprintf(name, "[%lu]", inode->i_ino);
+ this.name = name;
+ this.len = strlen(name);
+ this.hash = inode->i_ino;
+
+ ret = -ENOMEM;
+
+ /*
+ * allocate a new dcache entry
+ */
+ file->f_dentry = d_alloc(pfmfs_mnt->mnt_sb->s_root, &this);
+ if (!file->f_dentry) goto out;
+
+ file->f_dentry->d_op = &pfmfs_dentry_operations;
+
+ d_add(file->f_dentry, inode);
+ file->f_vfsmnt = mntget(pfmfs_mnt);
+ file->f_mapping = inode->i_mapping;
+
+ file->f_op = &pfm_file_ops;
+ file->f_mode = FMODE_READ;
+ file->f_flags = O_RDONLY;
+ file->f_pos = 0;
+
+ /*
+ * may have to delay until context is attached?
+ */
+ fd_install(fd, file);
+
+ /*
+ * the file structure we will use
+ */
+ *cfile = file;
+
+ return fd;
+out:
+ if (file) put_filp(file);
+ put_unused_fd(fd);
+ return ret;
+}
+
+static void
+pfm_free_fd(int fd, struct file *file)
+{
+ struct files_struct *files = current->files;
+
+ /*
+ * there ie no fd_uninstall(), so we do it here
+ */
+ spin_lock(&files->file_lock);
+ files->fd[fd] = NULL;
+ spin_unlock(&files->file_lock);
+
+ if (file) put_filp(file);
+ put_unused_fd(fd);
+}
+
+static int
+pfm_remap_buffer(struct vm_area_struct *vma, unsigned long buf, unsigned long addr, unsigned long size)
+{
+ DPRINT(("CPU%d buf=0x%lx addr=0x%lx size=%ld\n", smp_processor_id(), buf, addr, size));
+
+ while (size > 0) {
+ unsigned long pfn = ia64_tpa(buf) >> PAGE_SHIFT;
+
+
+ if (remap_pfn_range(vma, addr, pfn, PAGE_SIZE, PAGE_READONLY))
+ return -ENOMEM;
+
+ addr += PAGE_SIZE;
+ buf += PAGE_SIZE;
+ size -= PAGE_SIZE;
+ }
+ return 0;
+}
+
+/*
+ * allocate a sampling buffer and remaps it into the user address space of the task
+ */
+static int
+pfm_smpl_buffer_alloc(struct task_struct *task, pfm_context_t *ctx, unsigned long rsize, void **user_vaddr)
+{
+ struct mm_struct *mm = task->mm;
+ struct vm_area_struct *vma = NULL;
+ unsigned long size;
+ void *smpl_buf;
+
+
+ /*
+ * the fixed header + requested size and align to page boundary
+ */
+ size = PAGE_ALIGN(rsize);
+
+ DPRINT(("sampling buffer rsize=%lu size=%lu bytes\n", rsize, size));
+
+ /*
+ * check requested size to avoid Denial-of-service attacks
+ * XXX: may have to refine this test
+ * Check against address space limit.
+ *
+ * if ((mm->total_vm << PAGE_SHIFT) + len> task->rlim[RLIMIT_AS].rlim_cur)
+ * return -ENOMEM;
+ */
+ if (size > task->signal->rlim[RLIMIT_MEMLOCK].rlim_cur)
+ return -ENOMEM;
+
+ /*
+ * We do the easy to undo allocations first.
+ *
+ * pfm_rvmalloc(), clears the buffer, so there is no leak
+ */
+ smpl_buf = pfm_rvmalloc(size);
+ if (smpl_buf == NULL) {
+ DPRINT(("Can't allocate sampling buffer\n"));
+ return -ENOMEM;
+ }
+
+ DPRINT(("smpl_buf @%p\n", smpl_buf));
+
+ /* allocate vma */
+ vma = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);
+ if (!vma) {
+ DPRINT(("Cannot allocate vma\n"));
+ goto error_kmem;
+ }
+ memset(vma, 0, sizeof(*vma));
+
+ /*
+ * partially initialize the vma for the sampling buffer
+ */
+ vma->vm_mm = mm;
+ vma->vm_flags = VM_READ| VM_MAYREAD |VM_RESERVED;
+ vma->vm_page_prot = PAGE_READONLY; /* XXX may need to change */
+
+ /*
+ * Now we have everything we need and we can initialize
+ * and connect all the data structures
+ */
+
+ ctx->ctx_smpl_hdr = smpl_buf;
+ ctx->ctx_smpl_size = size; /* aligned size */
+
+ /*
+ * Let's do the difficult operations next.
+ *
+ * now we atomically find some area in the address space and
+ * remap the buffer in it.
+ */
+ down_write(&task->mm->mmap_sem);
+
+ /* find some free area in address space, must have mmap sem held */
+ vma->vm_start = pfm_get_unmapped_area(NULL, 0, size, 0, MAP_PRIVATE|MAP_ANONYMOUS, 0);
+ if (vma->vm_start == 0UL) {
+ DPRINT(("Cannot find unmapped area for size %ld\n", size));
+ up_write(&task->mm->mmap_sem);
+ goto error;
+ }
+ vma->vm_end = vma->vm_start + size;
+ vma->vm_pgoff = vma->vm_start >> PAGE_SHIFT;
+
+ DPRINT(("aligned size=%ld, hdr=%p mapped @0x%lx\n", size, ctx->ctx_smpl_hdr, vma->vm_start));
+
+ /* can only be applied to current task, need to have the mm semaphore held when called */
+ if (pfm_remap_buffer(vma, (unsigned long)smpl_buf, vma->vm_start, size)) {
+ DPRINT(("Can't remap buffer\n"));
+ up_write(&task->mm->mmap_sem);
+ goto error;
+ }
+
+ /*
+ * now insert the vma in the vm list for the process, must be
+ * done with mmap lock held
+ */
+ insert_vm_struct(mm, vma);
+
+ mm->total_vm += size >> PAGE_SHIFT;
+ vm_stat_account(vma);
+ up_write(&task->mm->mmap_sem);
+
+ /*
+ * keep track of user level virtual address
+ */
+ ctx->ctx_smpl_vaddr = (void *)vma->vm_start;
+ *(unsigned long *)user_vaddr = vma->vm_start;
+
+ return 0;
+
+error:
+ kmem_cache_free(vm_area_cachep, vma);
+error_kmem:
+ pfm_rvfree(smpl_buf, size);
+
+ return -ENOMEM;
+}
+
+/*
+ * XXX: do something better here
+ */
+static int
+pfm_bad_permissions(struct task_struct *task)
+{
+ /* inspired by ptrace_attach() */
+ DPRINT(("cur: uid=%d gid=%d task: euid=%d suid=%d uid=%d egid=%d sgid=%d\n",
+ current->uid,
+ current->gid,
+ task->euid,
+ task->suid,
+ task->uid,
+ task->egid,
+ task->sgid));
+
+ return ((current->uid != task->euid)
+ || (current->uid != task->suid)
+ || (current->uid != task->uid)
+ || (current->gid != task->egid)
+ || (current->gid != task->sgid)
+ || (current->gid != task->gid)) && !capable(CAP_SYS_PTRACE);
+}
+
+static int
+pfarg_is_sane(struct task_struct *task, pfarg_context_t *pfx)
+{
+ int ctx_flags;
+
+ /* valid signal */
+
+ ctx_flags = pfx->ctx_flags;
+
+ if (ctx_flags & PFM_FL_SYSTEM_WIDE) {
+
+ /*
+ * cannot block in this mode
+ */
+ if (ctx_flags & PFM_FL_NOTIFY_BLOCK) {
+ DPRINT(("cannot use blocking mode when in system wide monitoring\n"));
+ return -EINVAL;
+ }
+ } else {
+ }
+ /* probably more to add here */
+
+ return 0;
+}
+
+static int
+pfm_setup_buffer_fmt(struct task_struct *task, pfm_context_t *ctx, unsigned int ctx_flags,
+ unsigned int cpu, pfarg_context_t *arg)
+{
+ pfm_buffer_fmt_t *fmt = NULL;
+ unsigned long size = 0UL;
+ void *uaddr = NULL;
+ void *fmt_arg = NULL;
+ int ret = 0;
+#define PFM_CTXARG_BUF_ARG(a) (pfm_buffer_fmt_t *)(a+1)
+
+ /* invoke and lock buffer format, if found */
+ fmt = pfm_find_buffer_fmt(arg->ctx_smpl_buf_id);
+ if (fmt == NULL) {
+ DPRINT(("[%d] cannot find buffer format\n", task->pid));
+ return -EINVAL;
+ }
+
+ /*
+ * buffer argument MUST be contiguous to pfarg_context_t
+ */
+ if (fmt->fmt_arg_size) fmt_arg = PFM_CTXARG_BUF_ARG(arg);
+
+ ret = pfm_buf_fmt_validate(fmt, task, ctx_flags, cpu, fmt_arg);
+
+ DPRINT(("[%d] after validate(0x%x,%d,%p)=%d\n", task->pid, ctx_flags, cpu, fmt_arg, ret));
+
+ if (ret) goto error;
+
+ /* link buffer format and context */
+ ctx->ctx_buf_fmt = fmt;
+
+ /*
+ * check if buffer format wants to use perfmon buffer allocation/mapping service
+ */
+ ret = pfm_buf_fmt_getsize(fmt, task, ctx_flags, cpu, fmt_arg, &size);
+ if (ret) goto error;
+
+ if (size) {
+ /*
+ * buffer is always remapped into the caller's address space
+ */
+ ret = pfm_smpl_buffer_alloc(current, ctx, size, &uaddr);
+ if (ret) goto error;
+
+ /* keep track of user address of buffer */
+ arg->ctx_smpl_vaddr = uaddr;
+ }
+ ret = pfm_buf_fmt_init(fmt, task, ctx->ctx_smpl_hdr, ctx_flags, cpu, fmt_arg);
+
+error:
+ return ret;
+}
+
+static void
+pfm_reset_pmu_state(pfm_context_t *ctx)
+{
+ int i;
+
+ /*
+ * install reset values for PMC.
+ */
+ for (i=1; PMC_IS_LAST(i) == 0; i++) {
+ if (PMC_IS_IMPL(i) == 0) continue;
+ ctx->ctx_pmcs[i] = PMC_DFL_VAL(i);
+ DPRINT(("pmc[%d]=0x%lx\n", i, ctx->ctx_pmcs[i]));
+ }
+ /*
+ * PMD registers are set to 0UL when the context in memset()
+ */
+
+ /*
+ * On context switched restore, we must restore ALL pmc and ALL pmd even
+ * when they are not actively used by the task. In UP, the incoming process
+ * may otherwise pick up left over PMC, PMD state from the previous process.
+ * As opposed to PMD, stale PMC can cause harm to the incoming
+ * process because they may change what is being measured.
+ * Therefore, we must systematically reinstall the entire
+ * PMC state. In SMP, the same thing is possible on the
+ * same CPU but also on between 2 CPUs.
+ *
+ * The problem with PMD is information leaking especially
+ * to user level when psr.sp=0
+ *
+ * There is unfortunately no easy way to avoid this problem
+ * on either UP or SMP. This definitively slows down the
+ * pfm_load_regs() function.
+ */
+
+ /*
+ * bitmask of all PMCs accessible to this context
+ *
+ * PMC0 is treated differently.
+ */
+ ctx->ctx_all_pmcs[0] = pmu_conf->impl_pmcs[0] & ~0x1;
+
+ /*
+ * bitmask of all PMDs that are accesible to this context
+ */
+ ctx->ctx_all_pmds[0] = pmu_conf->impl_pmds[0];
+
+ DPRINT(("<%d> all_pmcs=0x%lx all_pmds=0x%lx\n", ctx->ctx_fd, ctx->ctx_all_pmcs[0],ctx->ctx_all_pmds[0]));
+
+ /*
+ * useful in case of re-enable after disable
+ */
+ ctx->ctx_used_ibrs[0] = 0UL;
+ ctx->ctx_used_dbrs[0] = 0UL;
+}
+
+static int
+pfm_ctx_getsize(void *arg, size_t *sz)
+{
+ pfarg_context_t *req = (pfarg_context_t *)arg;
+ pfm_buffer_fmt_t *fmt;
+
+ *sz = 0;
+
+ if (!pfm_uuid_cmp(req->ctx_smpl_buf_id, pfm_null_uuid)) return 0;
+
+ fmt = pfm_find_buffer_fmt(req->ctx_smpl_buf_id);
+ if (fmt == NULL) {
+ DPRINT(("cannot find buffer format\n"));
+ return -EINVAL;
+ }
+ /* get just enough to copy in user parameters */
+ *sz = fmt->fmt_arg_size;
+ DPRINT(("arg_size=%lu\n", *sz));
+
+ return 0;
+}
+
+
+
+/*
+ * cannot attach if :
+ * - kernel task
+ * - task not owned by caller
+ * - task incompatible with context mode
+ */
+static int
+pfm_task_incompatible(pfm_context_t *ctx, struct task_struct *task)
+{
+ /*
+ * no kernel task or task not owner by caller
+ */
+ if (task->mm == NULL) {
+ DPRINT(("task [%d] has not memory context (kernel thread)\n", task->pid));
+ return -EPERM;
+ }
+ if (pfm_bad_permissions(task)) {
+ DPRINT(("no permission to attach to [%d]\n", task->pid));
+ return -EPERM;
+ }
+ /*
+ * cannot block in self-monitoring mode
+ */
+ if (CTX_OVFL_NOBLOCK(ctx) == 0 && task == current) {
+ DPRINT(("cannot load a blocking context on self for [%d]\n", task->pid));
+ return -EINVAL;
+ }
+
+ if (task->exit_state == EXIT_ZOMBIE) {
+ DPRINT(("cannot attach to zombie task [%d]\n", task->pid));
+ return -EBUSY;
+ }
+
+ /*
+ * always ok for self
+ */
+ if (task == current) return 0;
+
+ if ((task->state != TASK_STOPPED) && (task->state != TASK_TRACED)) {
+ DPRINT(("cannot attach to non-stopped task [%d] state=%ld\n", task->pid, task->state));
+ return -EBUSY;
+ }
+ /*
+ * make sure the task is off any CPU
+ */
+ wait_task_inactive(task);
+
+ /* more to come... */
+
+ return 0;
+}
+
+static int
+pfm_get_task(pfm_context_t *ctx, pid_t pid, struct task_struct **task)
+{
+ struct task_struct *p = current;
+ int ret;
+
+ /* XXX: need to add more checks here */
+ if (pid < 2) return -EPERM;
+
+ if (pid != current->pid) {
+
+ read_lock(&tasklist_lock);
+
+ p = find_task_by_pid(pid);
+
+ /* make sure task cannot go away while we operate on it */
+ if (p) get_task_struct(p);
+
+ read_unlock(&tasklist_lock);
+
+ if (p == NULL) return -ESRCH;
+ }
+
+ ret = pfm_task_incompatible(ctx, p);
+ if (ret == 0) {
+ *task = p;
+ } else if (p != current) {
+ pfm_put_task(p);
+ }
+ return ret;
+}
+
+
+
+static int
+pfm_context_create(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+{
+ pfarg_context_t *req = (pfarg_context_t *)arg;
+ struct file *filp;
+ int ctx_flags;
+ int ret;
+
+ /* let's check the arguments first */
+ ret = pfarg_is_sane(current, req);
+ if (ret < 0) return ret;
+
+ ctx_flags = req->ctx_flags;
+
+ ret = -ENOMEM;
+
+ ctx = pfm_context_alloc();
+ if (!ctx) goto error;
+
+ ret = pfm_alloc_fd(&filp);
+ if (ret < 0) goto error_file;
+
+ req->ctx_fd = ctx->ctx_fd = ret;
+
+ /*
+ * attach context to file
+ */
+ filp->private_data = ctx;
+
+ /*
+ * does the user want to sample?
+ */
+ if (pfm_uuid_cmp(req->ctx_smpl_buf_id, pfm_null_uuid)) {
+ ret = pfm_setup_buffer_fmt(current, ctx, ctx_flags, 0, req);
+ if (ret) goto buffer_error;
+ }
+
+ /*
+ * init context protection lock
+ */
+ spin_lock_init(&ctx->ctx_lock);
+
+ /*
+ * context is unloaded
+ */
+ ctx->ctx_state = PFM_CTX_UNLOADED;
+
+ /*
+ * initialization of context's flags
+ */
+ ctx->ctx_fl_block = (ctx_flags & PFM_FL_NOTIFY_BLOCK) ? 1 : 0;
+ ctx->ctx_fl_system = (ctx_flags & PFM_FL_SYSTEM_WIDE) ? 1: 0;
+ ctx->ctx_fl_is_sampling = ctx->ctx_buf_fmt ? 1 : 0; /* assume record() is defined */
+ ctx->ctx_fl_no_msg = (ctx_flags & PFM_FL_OVFL_NO_MSG) ? 1: 0;
+ /*
+ * will move to set properties
+ * ctx->ctx_fl_excl_idle = (ctx_flags & PFM_FL_EXCL_IDLE) ? 1: 0;
+ */
+
+ /*
+ * init restart semaphore to locked
+ */
+ sema_init(&ctx->ctx_restart_sem, 0);
+
+ /*
+ * activation is used in SMP only
+ */
+ ctx->ctx_last_activation = PFM_INVALID_ACTIVATION;
+ SET_LAST_CPU(ctx, -1);
+
+ /*
+ * initialize notification message queue
+ */
+ ctx->ctx_msgq_head = ctx->ctx_msgq_tail = 0;
+ init_waitqueue_head(&ctx->ctx_msgq_wait);
+ init_waitqueue_head(&ctx->ctx_zombieq);
+
+ DPRINT(("ctx=%p flags=0x%x system=%d notify_block=%d excl_idle=%d no_msg=%d ctx_fd=%d \n",
+ ctx,
+ ctx_flags,
+ ctx->ctx_fl_system,
+ ctx->ctx_fl_block,
+ ctx->ctx_fl_excl_idle,
+ ctx->ctx_fl_no_msg,
+ ctx->ctx_fd));
+
+ /*
+ * initialize soft PMU state
+ */
+ pfm_reset_pmu_state(ctx);
+
+ return 0;
+
+buffer_error:
+ pfm_free_fd(ctx->ctx_fd, filp);
+
+ if (ctx->ctx_buf_fmt) {
+ pfm_buf_fmt_exit(ctx->ctx_buf_fmt, current, NULL, regs);
+ }
+error_file:
+ pfm_context_free(ctx);
+
+error:
+ return ret;
+}
+
+static inline unsigned long
+pfm_new_counter_value (pfm_counter_t *reg, int is_long_reset)
+{
+ unsigned long val = is_long_reset ? reg->long_reset : reg->short_reset;
+ unsigned long new_seed, old_seed = reg->seed, mask = reg->mask;
+ extern unsigned long carta_random32 (unsigned long seed);
+
+ if (reg->flags & PFM_REGFL_RANDOM) {
+ new_seed = carta_random32(old_seed);
+ val -= (old_seed & mask); /* counter values are negative numbers! */
+ if ((mask >> 32) != 0)
+ /* construct a full 64-bit random value: */
+ new_seed |= carta_random32(old_seed >> 32) << 32;
+ reg->seed = new_seed;
+ }
+ reg->lval = val;
+ return val;
+}
+
+static void
+pfm_reset_regs_masked(pfm_context_t *ctx, unsigned long *ovfl_regs, int is_long_reset)
+{
+ unsigned long mask = ovfl_regs[0];
+ unsigned long reset_others = 0UL;
+ unsigned long val;
+ int i;
+
+ /*
+ * now restore reset value on sampling overflowed counters
+ */
+ mask >>= PMU_FIRST_COUNTER;
+ for(i = PMU_FIRST_COUNTER; mask; i++, mask >>= 1) {
+
+ if ((mask & 0x1UL) == 0UL) continue;
+
+ ctx->ctx_pmds[i].val = val = pfm_new_counter_value(ctx->ctx_pmds+ i, is_long_reset);
+ reset_others |= ctx->ctx_pmds[i].reset_pmds[0];
+
+ DPRINT_ovfl((" %s reset ctx_pmds[%d]=%lx\n", is_long_reset ? "long" : "short", i, val));
+ }
+
+ /*
+ * Now take care of resetting the other registers
+ */
+ for(i = 0; reset_others; i++, reset_others >>= 1) {
+
+ if ((reset_others & 0x1) == 0) continue;
+
+ ctx->ctx_pmds[i].val = val = pfm_new_counter_value(ctx->ctx_pmds + i, is_long_reset);
+
+ DPRINT_ovfl(("%s reset_others pmd[%d]=%lx\n",
+ is_long_reset ? "long" : "short", i, val));
+ }
+}
+
+static void
+pfm_reset_regs(pfm_context_t *ctx, unsigned long *ovfl_regs, int is_long_reset)
+{
+ unsigned long mask = ovfl_regs[0];
+ unsigned long reset_others = 0UL;
+ unsigned long val;
+ int i;
+
+ DPRINT_ovfl(("ovfl_regs=0x%lx is_long_reset=%d\n", ovfl_regs[0], is_long_reset));
+
+ if (ctx->ctx_state == PFM_CTX_MASKED) {
+ pfm_reset_regs_masked(ctx, ovfl_regs, is_long_reset);
+ return;
+ }
+
+ /*
+ * now restore reset value on sampling overflowed counters
+ */
+ mask >>= PMU_FIRST_COUNTER;
+ for(i = PMU_FIRST_COUNTER; mask; i++, mask >>= 1) {
+
+ if ((mask & 0x1UL) == 0UL) continue;
+
+ val = pfm_new_counter_value(ctx->ctx_pmds+ i, is_long_reset);
+ reset_others |= ctx->ctx_pmds[i].reset_pmds[0];
+
+ DPRINT_ovfl((" %s reset ctx_pmds[%d]=%lx\n", is_long_reset ? "long" : "short", i, val));
+
+ pfm_write_soft_counter(ctx, i, val);
+ }
+
+ /*
+ * Now take care of resetting the other registers
+ */
+ for(i = 0; reset_others; i++, reset_others >>= 1) {
+
+ if ((reset_others & 0x1) == 0) continue;
+
+ val = pfm_new_counter_value(ctx->ctx_pmds + i, is_long_reset);
+
+ if (PMD_IS_COUNTING(i)) {
+ pfm_write_soft_counter(ctx, i, val);
+ } else {
+ ia64_set_pmd(i, val);
+ }
+ DPRINT_ovfl(("%s reset_others pmd[%d]=%lx\n",
+ is_long_reset ? "long" : "short", i, val));
+ }
+ ia64_srlz_d();
+}
+
+static int
+pfm_write_pmcs(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+{
+ struct thread_struct *thread = NULL;
+ struct task_struct *task;
+ pfarg_reg_t *req = (pfarg_reg_t *)arg;
+ unsigned long value, pmc_pm;
+ unsigned long smpl_pmds, reset_pmds, impl_pmds;
+ unsigned int cnum, reg_flags, flags, pmc_type;
+ int i, can_access_pmu = 0, is_loaded, is_system, expert_mode;
+ int is_monitor, is_counting, state;
+ int ret = -EINVAL;
+ pfm_reg_check_t wr_func;
+#define PFM_CHECK_PMC_PM(x, y, z) ((x)->ctx_fl_system ^ PMC_PM(y, z))
+
+ state = ctx->ctx_state;
+ is_loaded = state == PFM_CTX_LOADED ? 1 : 0;
+ is_system = ctx->ctx_fl_system;
+ task = ctx->ctx_task;
+ impl_pmds = pmu_conf->impl_pmds[0];
+
+ if (state == PFM_CTX_ZOMBIE) return -EINVAL;
+
+ if (is_loaded) {
+ thread = &task->thread;
+ /*
+ * In system wide and when the context is loaded, access can only happen
+ * when the caller is running on the CPU being monitored by the session.
+ * It does not have to be the owner (ctx_task) of the context per se.
+ */
+ if (is_system && ctx->ctx_cpu != smp_processor_id()) {
+ DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu));
+ return -EBUSY;
+ }
+ can_access_pmu = GET_PMU_OWNER() == task || is_system ? 1 : 0;
+ }
+ expert_mode = pfm_sysctl.expert_mode;
+
+ for (i = 0; i < count; i++, req++) {
+
+ cnum = req->reg_num;
+ reg_flags = req->reg_flags;
+ value = req->reg_value;
+ smpl_pmds = req->reg_smpl_pmds[0];
+ reset_pmds = req->reg_reset_pmds[0];
+ flags = 0;
+
+
+ if (cnum >= PMU_MAX_PMCS) {
+ DPRINT(("pmc%u is invalid\n", cnum));
+ goto error;
+ }
+
+ pmc_type = pmu_conf->pmc_desc[cnum].type;
+ pmc_pm = (value >> pmu_conf->pmc_desc[cnum].pm_pos) & 0x1;
+ is_counting = (pmc_type & PFM_REG_COUNTING) == PFM_REG_COUNTING ? 1 : 0;
+ is_monitor = (pmc_type & PFM_REG_MONITOR) == PFM_REG_MONITOR ? 1 : 0;
+
+ /*
+ * we reject all non implemented PMC as well
+ * as attempts to modify PMC[0-3] which are used
+ * as status registers by the PMU
+ */
+ if ((pmc_type & PFM_REG_IMPL) == 0 || (pmc_type & PFM_REG_CONTROL) == PFM_REG_CONTROL) {
+ DPRINT(("pmc%u is unimplemented or no-access pmc_type=%x\n", cnum, pmc_type));
+ goto error;
+ }
+ wr_func = pmu_conf->pmc_desc[cnum].write_check;
+ /*
+ * If the PMC is a monitor, then if the value is not the default:
+ * - system-wide session: PMCx.pm=1 (privileged monitor)
+ * - per-task : PMCx.pm=0 (user monitor)
+ */
+ if (is_monitor && value != PMC_DFL_VAL(cnum) && is_system ^ pmc_pm) {
+ DPRINT(("pmc%u pmc_pm=%lu is_system=%d\n",
+ cnum,
+ pmc_pm,
+ is_system));
+ goto error;
+ }
+
+ if (is_counting) {
+ /*
+ * enforce generation of overflow interrupt. Necessary on all
+ * CPUs.
+ */
+ value |= 1 << PMU_PMC_OI;
+
+ if (reg_flags & PFM_REGFL_OVFL_NOTIFY) {
+ flags |= PFM_REGFL_OVFL_NOTIFY;
+ }
+
+ if (reg_flags & PFM_REGFL_RANDOM) flags |= PFM_REGFL_RANDOM;
+
+ /* verify validity of smpl_pmds */
+ if ((smpl_pmds & impl_pmds) != smpl_pmds) {
+ DPRINT(("invalid smpl_pmds 0x%lx for pmc%u\n", smpl_pmds, cnum));
+ goto error;
+ }
+
+ /* verify validity of reset_pmds */
+ if ((reset_pmds & impl_pmds) != reset_pmds) {
+ DPRINT(("invalid reset_pmds 0x%lx for pmc%u\n", reset_pmds, cnum));
+ goto error;
+ }
+ } else {
+ if (reg_flags & (PFM_REGFL_OVFL_NOTIFY|PFM_REGFL_RANDOM)) {
+ DPRINT(("cannot set ovfl_notify or random on pmc%u\n", cnum));
+ goto error;
+ }
+ /* eventid on non-counting monitors are ignored */
+ }
+
+ /*
+ * execute write checker, if any
+ */
+ if (likely(expert_mode == 0 && wr_func)) {
+ ret = (*wr_func)(task, ctx, cnum, &value, regs);
+ if (ret) goto error;
+ ret = -EINVAL;
+ }
+
+ /*
+ * no error on this register
+ */
+ PFM_REG_RETFLAG_SET(req->reg_flags, 0);
+
+ /*
+ * Now we commit the changes to the software state
+ */
+
+ /*
+ * update overflow information
+ */
+ if (is_counting) {
+ /*
+ * full flag update each time a register is programmed
+ */
+ ctx->ctx_pmds[cnum].flags = flags;
+
+ ctx->ctx_pmds[cnum].reset_pmds[0] = reset_pmds;
+ ctx->ctx_pmds[cnum].smpl_pmds[0] = smpl_pmds;
+ ctx->ctx_pmds[cnum].eventid = req->reg_smpl_eventid;
+
+ /*
+ * Mark all PMDS to be accessed as used.
+ *
+ * We do not keep track of PMC because we have to
+ * systematically restore ALL of them.
+ *
+ * We do not update the used_monitors mask, because
+ * if we have not programmed them, then will be in
+ * a quiescent state, therefore we will not need to
+ * mask/restore then when context is MASKED.
+ */
+ CTX_USED_PMD(ctx, reset_pmds);
+ CTX_USED_PMD(ctx, smpl_pmds);
+ /*
+ * make sure we do not try to reset on
+ * restart because we have established new values
+ */
+ if (state == PFM_CTX_MASKED) ctx->ctx_ovfl_regs[0] &= ~1UL << cnum;
+ }
+ /*
+ * Needed in case the user does not initialize the equivalent
+ * PMD. Clearing is done indirectly via pfm_reset_pmu_state() so there is no
+ * possible leak here.
+ */
+ CTX_USED_PMD(ctx, pmu_conf->pmc_desc[cnum].dep_pmd[0]);
+
+ /*
+ * keep track of the monitor PMC that we are using.
+ * we save the value of the pmc in ctx_pmcs[] and if
+ * the monitoring is not stopped for the context we also
+ * place it in the saved state area so that it will be
+ * picked up later by the context switch code.
+ *
+ * The value in ctx_pmcs[] can only be changed in pfm_write_pmcs().
+ *
+ * The value in thread->pmcs[] may be modified on overflow, i.e., when
+ * monitoring needs to be stopped.
+ */
+ if (is_monitor) CTX_USED_MONITOR(ctx, 1UL << cnum);
+
+ /*
+ * update context state
+ */
+ ctx->ctx_pmcs[cnum] = value;
+
+ if (is_loaded) {
+ /*
+ * write thread state
+ */
+ if (is_system == 0) thread->pmcs[cnum] = value;
+
+ /*
+ * write hardware register if we can
+ */
+ if (can_access_pmu) {
+ ia64_set_pmc(cnum, value);
+ }
+#ifdef CONFIG_SMP
+ else {
+ /*
+ * per-task SMP only here
+ *
+ * we are guaranteed that the task is not running on the other CPU,
+ * we indicate that this PMD will need to be reloaded if the task
+ * is rescheduled on the CPU it ran last on.
+ */
+ ctx->ctx_reload_pmcs[0] |= 1UL << cnum;
+ }
+#endif
+ }
+
+ DPRINT(("pmc[%u]=0x%lx ld=%d apmu=%d flags=0x%x all_pmcs=0x%lx used_pmds=0x%lx eventid=%ld smpl_pmds=0x%lx reset_pmds=0x%lx reloads_pmcs=0x%lx used_monitors=0x%lx ovfl_regs=0x%lx\n",
+ cnum,
+ value,
+ is_loaded,
+ can_access_pmu,
+ flags,
+ ctx->ctx_all_pmcs[0],
+ ctx->ctx_used_pmds[0],
+ ctx->ctx_pmds[cnum].eventid,
+ smpl_pmds,
+ reset_pmds,
+ ctx->ctx_reload_pmcs[0],
+ ctx->ctx_used_monitors[0],
+ ctx->ctx_ovfl_regs[0]));
+ }
+
+ /*
+ * make sure the changes are visible
+ */
+ if (can_access_pmu) ia64_srlz_d();
+
+ return 0;
+error:
+ PFM_REG_RETFLAG_SET(req->reg_flags, PFM_REG_RETFL_EINVAL);
+ return ret;
+}
+
+static int
+pfm_write_pmds(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+{
+ struct thread_struct *thread = NULL;
+ struct task_struct *task;
+ pfarg_reg_t *req = (pfarg_reg_t *)arg;
+ unsigned long value, hw_value, ovfl_mask;
+ unsigned int cnum;
+ int i, can_access_pmu = 0, state;
+ int is_counting, is_loaded, is_system, expert_mode;
+ int ret = -EINVAL;
+ pfm_reg_check_t wr_func;
+
+
+ state = ctx->ctx_state;
+ is_loaded = state == PFM_CTX_LOADED ? 1 : 0;
+ is_system = ctx->ctx_fl_system;
+ ovfl_mask = pmu_conf->ovfl_val;
+ task = ctx->ctx_task;
+
+ if (unlikely(state == PFM_CTX_ZOMBIE)) return -EINVAL;
+
+ /*
+ * on both UP and SMP, we can only write to the PMC when the task is
+ * the owner of the local PMU.
+ */
+ if (likely(is_loaded)) {
+ thread = &task->thread;
+ /*
+ * In system wide and when the context is loaded, access can only happen
+ * when the caller is running on the CPU being monitored by the session.
+ * It does not have to be the owner (ctx_task) of the context per se.
+ */
+ if (unlikely(is_system && ctx->ctx_cpu != smp_processor_id())) {
+ DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu));
+ return -EBUSY;
+ }
+ can_access_pmu = GET_PMU_OWNER() == task || is_system ? 1 : 0;
+ }
+ expert_mode = pfm_sysctl.expert_mode;
+
+ for (i = 0; i < count; i++, req++) {
+
+ cnum = req->reg_num;
+ value = req->reg_value;
+
+ if (!PMD_IS_IMPL(cnum)) {
+ DPRINT(("pmd[%u] is unimplemented or invalid\n", cnum));
+ goto abort_mission;
+ }
+ is_counting = PMD_IS_COUNTING(cnum);
+ wr_func = pmu_conf->pmd_desc[cnum].write_check;
+
+ /*
+ * execute write checker, if any
+ */
+ if (unlikely(expert_mode == 0 && wr_func)) {
+ unsigned long v = value;
+
+ ret = (*wr_func)(task, ctx, cnum, &v, regs);
+ if (ret) goto abort_mission;
+
+ value = v;
+ ret = -EINVAL;
+ }
+
+ /*
+ * no error on this register
+ */
+ PFM_REG_RETFLAG_SET(req->reg_flags, 0);
+
+ /*
+ * now commit changes to software state
+ */
+ hw_value = value;
+
+ /*
+ * update virtualized (64bits) counter
+ */
+ if (is_counting) {
+ /*
+ * write context state
+ */
+ ctx->ctx_pmds[cnum].lval = value;
+
+ /*
+ * when context is load we use the split value
+ */
+ if (is_loaded) {
+ hw_value = value & ovfl_mask;
+ value = value & ~ovfl_mask;
+ }
+ }
+ /*
+ * update reset values (not just for counters)
+ */
+ ctx->ctx_pmds[cnum].long_reset = req->reg_long_reset;
+ ctx->ctx_pmds[cnum].short_reset = req->reg_short_reset;
+
+ /*
+ * update randomization parameters (not just for counters)
+ */
+ ctx->ctx_pmds[cnum].seed = req->reg_random_seed;
+ ctx->ctx_pmds[cnum].mask = req->reg_random_mask;
+
+ /*
+ * update context value
+ */
+ ctx->ctx_pmds[cnum].val = value;
+
+ /*
+ * Keep track of what we use
+ *
+ * We do not keep track of PMC because we have to
+ * systematically restore ALL of them.
+ */
+ CTX_USED_PMD(ctx, PMD_PMD_DEP(cnum));
+
+ /*
+ * mark this PMD register used as well
+ */
+ CTX_USED_PMD(ctx, RDEP(cnum));
+
+ /*
+ * make sure we do not try to reset on
+ * restart because we have established new values
+ */
+ if (is_counting && state == PFM_CTX_MASKED) {
+ ctx->ctx_ovfl_regs[0] &= ~1UL << cnum;
+ }
+
+ if (is_loaded) {
+ /*
+ * write thread state
+ */
+ if (is_system == 0) thread->pmds[cnum] = hw_value;
+
+ /*
+ * write hardware register if we can
+ */
+ if (can_access_pmu) {
+ ia64_set_pmd(cnum, hw_value);
+ } else {
+#ifdef CONFIG_SMP
+ /*
+ * we are guaranteed that the task is not running on the other CPU,
+ * we indicate that this PMD will need to be reloaded if the task
+ * is rescheduled on the CPU it ran last on.
+ */
+ ctx->ctx_reload_pmds[0] |= 1UL << cnum;
+#endif
+ }
+ }
+
+ DPRINT(("pmd[%u]=0x%lx ld=%d apmu=%d, hw_value=0x%lx ctx_pmd=0x%lx short_reset=0x%lx "
+ "long_reset=0x%lx notify=%c seed=0x%lx mask=0x%lx used_pmds=0x%lx reset_pmds=0x%lx reload_pmds=0x%lx all_pmds=0x%lx ovfl_regs=0x%lx\n",
+ cnum,
+ value,
+ is_loaded,
+ can_access_pmu,
+ hw_value,
+ ctx->ctx_pmds[cnum].val,
+ ctx->ctx_pmds[cnum].short_reset,
+ ctx->ctx_pmds[cnum].long_reset,
+ PMC_OVFL_NOTIFY(ctx, cnum) ? 'Y':'N',
+ ctx->ctx_pmds[cnum].seed,
+ ctx->ctx_pmds[cnum].mask,
+ ctx->ctx_used_pmds[0],
+ ctx->ctx_pmds[cnum].reset_pmds[0],
+ ctx->ctx_reload_pmds[0],
+ ctx->ctx_all_pmds[0],
+ ctx->ctx_ovfl_regs[0]));
+ }
+
+ /*
+ * make changes visible
+ */
+ if (can_access_pmu) ia64_srlz_d();
+
+ return 0;
+
+abort_mission:
+ /*
+ * for now, we have only one possibility for error
+ */
+ PFM_REG_RETFLAG_SET(req->reg_flags, PFM_REG_RETFL_EINVAL);
+ return ret;
+}
+
+/*
+ * By the way of PROTECT_CONTEXT(), interrupts are masked while we are in this function.
+ * Therefore we know, we do not have to worry about the PMU overflow interrupt. If an
+ * interrupt is delivered during the call, it will be kept pending until we leave, making
+ * it appears as if it had been generated at the UNPROTECT_CONTEXT(). At least we are
+ * guaranteed to return consistent data to the user, it may simply be old. It is not
+ * trivial to treat the overflow while inside the call because you may end up in
+ * some module sampling buffer code causing deadlocks.
+ */
+static int
+pfm_read_pmds(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+{
+ struct thread_struct *thread = NULL;
+ struct task_struct *task;
+ unsigned long val = 0UL, lval, ovfl_mask, sval;
+ pfarg_reg_t *req = (pfarg_reg_t *)arg;
+ unsigned int cnum, reg_flags = 0;
+ int i, can_access_pmu = 0, state;
+ int is_loaded, is_system, is_counting, expert_mode;
+ int ret = -EINVAL;
+ pfm_reg_check_t rd_func;
+
+ /*
+ * access is possible when loaded only for
+ * self-monitoring tasks or in UP mode
+ */
+
+ state = ctx->ctx_state;
+ is_loaded = state == PFM_CTX_LOADED ? 1 : 0;
+ is_system = ctx->ctx_fl_system;
+ ovfl_mask = pmu_conf->ovfl_val;
+ task = ctx->ctx_task;
+
+ if (state == PFM_CTX_ZOMBIE) return -EINVAL;
+
+ if (likely(is_loaded)) {
+ thread = &task->thread;
+ /*
+ * In system wide and when the context is loaded, access can only happen
+ * when the caller is running on the CPU being monitored by the session.
+ * It does not have to be the owner (ctx_task) of the context per se.
+ */
+ if (unlikely(is_system && ctx->ctx_cpu != smp_processor_id())) {
+ DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu));
+ return -EBUSY;
+ }
+ /*
+ * this can be true when not self-monitoring only in UP
+ */
+ can_access_pmu = GET_PMU_OWNER() == task || is_system ? 1 : 0;
+
+ if (can_access_pmu) ia64_srlz_d();
+ }
+ expert_mode = pfm_sysctl.expert_mode;
+
+ DPRINT(("ld=%d apmu=%d ctx_state=%d\n",
+ is_loaded,
+ can_access_pmu,
+ state));
+
+ /*
+ * on both UP and SMP, we can only read the PMD from the hardware register when
+ * the task is the owner of the local PMU.
+ */
+
+ for (i = 0; i < count; i++, req++) {
+
+ cnum = req->reg_num;
+ reg_flags = req->reg_flags;
+
+ if (unlikely(!PMD_IS_IMPL(cnum))) goto error;
+ /*
+ * we can only read the register that we use. That includes
+ * the one we explicitely initialize AND the one we want included
+ * in the sampling buffer (smpl_regs).
+ *
+ * Having this restriction allows optimization in the ctxsw routine
+ * without compromising security (leaks)
+ */
+ if (unlikely(!CTX_IS_USED_PMD(ctx, cnum))) goto error;
+
+ sval = ctx->ctx_pmds[cnum].val;
+ lval = ctx->ctx_pmds[cnum].lval;
+ is_counting = PMD_IS_COUNTING(cnum);
+
+ /*
+ * If the task is not the current one, then we check if the
+ * PMU state is still in the local live register due to lazy ctxsw.
+ * If true, then we read directly from the registers.
+ */
+ if (can_access_pmu){
+ val = ia64_get_pmd(cnum);
+ } else {
+ /*
+ * context has been saved
+ * if context is zombie, then task does not exist anymore.
+ * In this case, we use the full value saved in the context (pfm_flush_regs()).
+ */
+ val = is_loaded ? thread->pmds[cnum] : 0UL;
+ }
+ rd_func = pmu_conf->pmd_desc[cnum].read_check;
+
+ if (is_counting) {
+ /*
+ * XXX: need to check for overflow when loaded
+ */
+ val &= ovfl_mask;
+ val += sval;
+ }
+
+ /*
+ * execute read checker, if any
+ */
+ if (unlikely(expert_mode == 0 && rd_func)) {
+ unsigned long v = val;
+ ret = (*rd_func)(ctx->ctx_task, ctx, cnum, &v, regs);
+ if (ret) goto error;
+ val = v;
+ ret = -EINVAL;
+ }
+
+ PFM_REG_RETFLAG_SET(reg_flags, 0);
+
+ DPRINT(("pmd[%u]=0x%lx\n", cnum, val));
+
+ /*
+ * update register return value, abort all if problem during copy.
+ * we only modify the reg_flags field. no check mode is fine because
+ * access has been verified upfront in sys_perfmonctl().
+ */
+ req->reg_value = val;
+ req->reg_flags = reg_flags;
+ req->reg_last_reset_val = lval;
+ }
+
+ return 0;
+
+error:
+ PFM_REG_RETFLAG_SET(req->reg_flags, PFM_REG_RETFL_EINVAL);
+ return ret;
+}
+
+int
+pfm_mod_write_pmcs(struct task_struct *task, void *req, unsigned int nreq, struct pt_regs *regs)
+{
+ pfm_context_t *ctx;
+
+ if (req == NULL) return -EINVAL;
+
+ ctx = GET_PMU_CTX();
+
+ if (ctx == NULL) return -EINVAL;
+
+ /*
+ * for now limit to current task, which is enough when calling
+ * from overflow handler
+ */
+ if (task != current && ctx->ctx_fl_system == 0) return -EBUSY;
+
+ return pfm_write_pmcs(ctx, req, nreq, regs);
+}
+EXPORT_SYMBOL(pfm_mod_write_pmcs);
+
+int
+pfm_mod_read_pmds(struct task_struct *task, void *req, unsigned int nreq, struct pt_regs *regs)
+{
+ pfm_context_t *ctx;
+
+ if (req == NULL) return -EINVAL;
+
+ ctx = GET_PMU_CTX();
+
+ if (ctx == NULL) return -EINVAL;
+
+ /*
+ * for now limit to current task, which is enough when calling
+ * from overflow handler
+ */
+ if (task != current && ctx->ctx_fl_system == 0) return -EBUSY;
+
+ return pfm_read_pmds(ctx, req, nreq, regs);
+}
+EXPORT_SYMBOL(pfm_mod_read_pmds);
+
+/*
+ * Only call this function when a process it trying to
+ * write the debug registers (reading is always allowed)
+ */
+int
+pfm_use_debug_registers(struct task_struct *task)
+{
+ pfm_context_t *ctx = task->thread.pfm_context;
+ unsigned long flags;
+ int ret = 0;
+
+ if (pmu_conf->use_rr_dbregs == 0) return 0;
+
+ DPRINT(("called for [%d]\n", task->pid));
+
+ /*
+ * do it only once
+ */
+ if (task->thread.flags & IA64_THREAD_DBG_VALID) return 0;
+
+ /*
+ * Even on SMP, we do not need to use an atomic here because
+ * the only way in is via ptrace() and this is possible only when the
+ * process is stopped. Even in the case where the ctxsw out is not totally
+ * completed by the time we come here, there is no way the 'stopped' process
+ * could be in the middle of fiddling with the pfm_write_ibr_dbr() routine.
+ * So this is always safe.
+ */
+ if (ctx && ctx->ctx_fl_using_dbreg == 1) return -1;
+
+ LOCK_PFS(flags);
+
+ /*
+ * We cannot allow setting breakpoints when system wide monitoring
+ * sessions are using the debug registers.
+ */
+ if (pfm_sessions.pfs_sys_use_dbregs> 0)
+ ret = -1;
+ else
+ pfm_sessions.pfs_ptrace_use_dbregs++;
+
+ DPRINT(("ptrace_use_dbregs=%u sys_use_dbregs=%u by [%d] ret = %d\n",
+ pfm_sessions.pfs_ptrace_use_dbregs,
+ pfm_sessions.pfs_sys_use_dbregs,
+ task->pid, ret));
+
+ UNLOCK_PFS(flags);
+
+ return ret;
+}
+
+/*
+ * This function is called for every task that exits with the
+ * IA64_THREAD_DBG_VALID set. This indicates a task which was
+ * able to use the debug registers for debugging purposes via
+ * ptrace(). Therefore we know it was not using them for
+ * perfmormance monitoring, so we only decrement the number
+ * of "ptraced" debug register users to keep the count up to date
+ */
+int
+pfm_release_debug_registers(struct task_struct *task)
+{
+ unsigned long flags;
+ int ret;
+
+ if (pmu_conf->use_rr_dbregs == 0) return 0;
+
+ LOCK_PFS(flags);
+ if (pfm_sessions.pfs_ptrace_use_dbregs == 0) {
+ printk(KERN_ERR "perfmon: invalid release for [%d] ptrace_use_dbregs=0\n", task->pid);
+ ret = -1;
+ } else {
+ pfm_sessions.pfs_ptrace_use_dbregs--;
+ ret = 0;
+ }
+ UNLOCK_PFS(flags);
+
+ return ret;
+}
+
+static int
+pfm_restart(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+{
+ struct task_struct *task;
+ pfm_buffer_fmt_t *fmt;
+ pfm_ovfl_ctrl_t rst_ctrl;
+ int state, is_system;
+ int ret = 0;
+
+ state = ctx->ctx_state;
+ fmt = ctx->ctx_buf_fmt;
+ is_system = ctx->ctx_fl_system;
+ task = PFM_CTX_TASK(ctx);
+
+ switch(state) {
+ case PFM_CTX_MASKED:
+ break;
+ case PFM_CTX_LOADED:
+ if (CTX_HAS_SMPL(ctx) && fmt->fmt_restart_active) break;
+ /* fall through */
+ case PFM_CTX_UNLOADED:
+ case PFM_CTX_ZOMBIE:
+ DPRINT(("invalid state=%d\n", state));
+ return -EBUSY;
+ default:
+ DPRINT(("state=%d, cannot operate (no active_restart handler)\n", state));
+ return -EINVAL;
+ }
+
+ /*
+ * In system wide and when the context is loaded, access can only happen
+ * when the caller is running on the CPU being monitored by the session.
+ * It does not have to be the owner (ctx_task) of the context per se.
+ */
+ if (is_system && ctx->ctx_cpu != smp_processor_id()) {
+ DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu));
+ return -EBUSY;
+ }
+
+ /* sanity check */
+ if (unlikely(task == NULL)) {
+ printk(KERN_ERR "perfmon: [%d] pfm_restart no task\n", current->pid);
+ return -EINVAL;
+ }
+
+ if (task == current || is_system) {
+
+ fmt = ctx->ctx_buf_fmt;
+
+ DPRINT(("restarting self %d ovfl=0x%lx\n",
+ task->pid,
+ ctx->ctx_ovfl_regs[0]));
+
+ if (CTX_HAS_SMPL(ctx)) {
+
+ prefetch(ctx->ctx_smpl_hdr);
+
+ rst_ctrl.bits.mask_monitoring = 0;
+ rst_ctrl.bits.reset_ovfl_pmds = 0;
+
+ if (state == PFM_CTX_LOADED)
+ ret = pfm_buf_fmt_restart_active(fmt, task, &rst_ctrl, ctx->ctx_smpl_hdr, regs);
+ else
+ ret = pfm_buf_fmt_restart(fmt, task, &rst_ctrl, ctx->ctx_smpl_hdr, regs);
+ } else {
+ rst_ctrl.bits.mask_monitoring = 0;
+ rst_ctrl.bits.reset_ovfl_pmds = 1;
+ }
+
+ if (ret == 0) {
+ if (rst_ctrl.bits.reset_ovfl_pmds)
+ pfm_reset_regs(ctx, ctx->ctx_ovfl_regs, PFM_PMD_LONG_RESET);
+
+ if (rst_ctrl.bits.mask_monitoring == 0) {
+ DPRINT(("resuming monitoring for [%d]\n", task->pid));
+
+ if (state == PFM_CTX_MASKED) pfm_restore_monitoring(task);
+ } else {
+ DPRINT(("keeping monitoring stopped for [%d]\n", task->pid));
+
+ // cannot use pfm_stop_monitoring(task, regs);
+ }
+ }
+ /*
+ * clear overflowed PMD mask to remove any stale information
+ */
+ ctx->ctx_ovfl_regs[0] = 0UL;
+
+ /*
+ * back to LOADED state
+ */
+ ctx->ctx_state = PFM_CTX_LOADED;
+
+ /*
+ * XXX: not really useful for self monitoring
+ */
+ ctx->ctx_fl_can_restart = 0;
+
+ return 0;
+ }
+
+ /*
+ * restart another task
+ */
+
+ /*
+ * When PFM_CTX_MASKED, we cannot issue a restart before the previous
+ * one is seen by the task.
+ */
+ if (state == PFM_CTX_MASKED) {
+ if (ctx->ctx_fl_can_restart == 0) return -EINVAL;
+ /*
+ * will prevent subsequent restart before this one is
+ * seen by other task
+ */
+ ctx->ctx_fl_can_restart = 0;
+ }
+
+ /*
+ * if blocking, then post the semaphore is PFM_CTX_MASKED, i.e.
+ * the task is blocked or on its way to block. That's the normal
+ * restart path. If the monitoring is not masked, then the task
+ * can be actively monitoring and we cannot directly intervene.
+ * Therefore we use the trap mechanism to catch the task and
+ * force it to reset the buffer/reset PMDs.
+ *
+ * if non-blocking, then we ensure that the task will go into
+ * pfm_handle_work() before returning to user mode.
+ *
+ * We cannot explicitely reset another task, it MUST always
+ * be done by the task itself. This works for system wide because
+ * the tool that is controlling the session is logically doing
+ * "self-monitoring".
+ */
+ if (CTX_OVFL_NOBLOCK(ctx) == 0 && state == PFM_CTX_MASKED) {
+ DPRINT(("unblocking [%d] \n", task->pid));
+ up(&ctx->ctx_restart_sem);
+ } else {
+ DPRINT(("[%d] armed exit trap\n", task->pid));
+
+ ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_RESET;
+
+ PFM_SET_WORK_PENDING(task, 1);
+
+ pfm_set_task_notify(task);
+
+ /*
+ * XXX: send reschedule if task runs on another CPU
+ */
+ }
+ return 0;
+}
+
+static int
+pfm_debug(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+{
+ unsigned int m = *(unsigned int *)arg;
+
+ pfm_sysctl.debug = m == 0 ? 0 : 1;
+
+ pfm_debug_var = pfm_sysctl.debug;
+
+ printk(KERN_INFO "perfmon debugging %s (timing reset)\n", pfm_sysctl.debug ? "on" : "off");
+
+ if (m == 0) {
+ memset(pfm_stats, 0, sizeof(pfm_stats));
+ for(m=0; m < NR_CPUS; m++) pfm_stats[m].pfm_ovfl_intr_cycles_min = ~0UL;
+ }
+ return 0;
+}
+
+/*
+ * arg can be NULL and count can be zero for this function
+ */
+static int
+pfm_write_ibr_dbr(int mode, pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+{
+ struct thread_struct *thread = NULL;
+ struct task_struct *task;
+ pfarg_dbreg_t *req = (pfarg_dbreg_t *)arg;
+ unsigned long flags;
+ dbreg_t dbreg;
+ unsigned int rnum;
+ int first_time;
+ int ret = 0, state;
+ int i, can_access_pmu = 0;
+ int is_system, is_loaded;
+
+ if (pmu_conf->use_rr_dbregs == 0) return -EINVAL;
+
+ state = ctx->ctx_state;
+ is_loaded = state == PFM_CTX_LOADED ? 1 : 0;
+ is_system = ctx->ctx_fl_system;
+ task = ctx->ctx_task;
+
+ if (state == PFM_CTX_ZOMBIE) return -EINVAL;
+
+ /*
+ * on both UP and SMP, we can only write to the PMC when the task is
+ * the owner of the local PMU.
+ */
+ if (is_loaded) {
+ thread = &task->thread;
+ /*
+ * In system wide and when the context is loaded, access can only happen
+ * when the caller is running on the CPU being monitored by the session.
+ * It does not have to be the owner (ctx_task) of the context per se.
+ */
+ if (unlikely(is_system && ctx->ctx_cpu != smp_processor_id())) {
+ DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu));
+ return -EBUSY;
+ }
+ can_access_pmu = GET_PMU_OWNER() == task || is_system ? 1 : 0;
+ }
+
+ /*
+ * we do not need to check for ipsr.db because we do clear ibr.x, dbr.r, and dbr.w
+ * ensuring that no real breakpoint can be installed via this call.
+ *
+ * IMPORTANT: regs can be NULL in this function
+ */
+
+ first_time = ctx->ctx_fl_using_dbreg == 0;
+
+ /*
+ * don't bother if we are loaded and task is being debugged
+ */
+ if (is_loaded && (thread->flags & IA64_THREAD_DBG_VALID) != 0) {
+ DPRINT(("debug registers already in use for [%d]\n", task->pid));
+ return -EBUSY;
+ }
+
+ /*
+ * check for debug registers in system wide mode
+ *
+ * If though a check is done in pfm_context_load(),
+ * we must repeat it here, in case the registers are
+ * written after the context is loaded
+ */
+ if (is_loaded) {
+ LOCK_PFS(flags);
+
+ if (first_time && is_system) {
+ if (pfm_sessions.pfs_ptrace_use_dbregs)
+ ret = -EBUSY;
+ else
+ pfm_sessions.pfs_sys_use_dbregs++;
+ }
+ UNLOCK_PFS(flags);
+ }
+
+ if (ret != 0) return ret;
+
+ /*
+ * mark ourself as user of the debug registers for
+ * perfmon purposes.
+ */
+ ctx->ctx_fl_using_dbreg = 1;
+
+ /*
+ * clear hardware registers to make sure we don't
+ * pick up stale state.
+ *
+ * for a system wide session, we do not use
+ * thread.dbr, thread.ibr because this process
+ * never leaves the current CPU and the state
+ * is shared by all processes running on it
+ */
+ if (first_time && can_access_pmu) {
+ DPRINT(("[%d] clearing ibrs, dbrs\n", task->pid));
+ for (i=0; i < pmu_conf->num_ibrs; i++) {
+ ia64_set_ibr(i, 0UL);
+ ia64_dv_serialize_instruction();
+ }
+ ia64_srlz_i();
+ for (i=0; i < pmu_conf->num_dbrs; i++) {
+ ia64_set_dbr(i, 0UL);
+ ia64_dv_serialize_data();
+ }
+ ia64_srlz_d();
+ }
+
+ /*
+ * Now install the values into the registers
+ */
+ for (i = 0; i < count; i++, req++) {
+
+ rnum = req->dbreg_num;
+ dbreg.val = req->dbreg_value;
+
+ ret = -EINVAL;
+
+ if ((mode == PFM_CODE_RR && rnum >= PFM_NUM_IBRS) || ((mode == PFM_DATA_RR) && rnum >= PFM_NUM_DBRS)) {
+ DPRINT(("invalid register %u val=0x%lx mode=%d i=%d count=%d\n",
+ rnum, dbreg.val, mode, i, count));
+
+ goto abort_mission;
+ }
+
+ /*
+ * make sure we do not install enabled breakpoint
+ */
+ if (rnum & 0x1) {
+ if (mode == PFM_CODE_RR)
+ dbreg.ibr.ibr_x = 0;
+ else
+ dbreg.dbr.dbr_r = dbreg.dbr.dbr_w = 0;
+ }
+
+ PFM_REG_RETFLAG_SET(req->dbreg_flags, 0);
+
+ /*
+ * Debug registers, just like PMC, can only be modified
+ * by a kernel call. Moreover, perfmon() access to those
+ * registers are centralized in this routine. The hardware
+ * does not modify the value of these registers, therefore,
+ * if we save them as they are written, we can avoid having
+ * to save them on context switch out. This is made possible
+ * by the fact that when perfmon uses debug registers, ptrace()
+ * won't be able to modify them concurrently.
+ */
+ if (mode == PFM_CODE_RR) {
+ CTX_USED_IBR(ctx, rnum);
+
+ if (can_access_pmu) {
+ ia64_set_ibr(rnum, dbreg.val);
+ ia64_dv_serialize_instruction();
+ }
+
+ ctx->ctx_ibrs[rnum] = dbreg.val;
+
+ DPRINT(("write ibr%u=0x%lx used_ibrs=0x%x ld=%d apmu=%d\n",
+ rnum, dbreg.val, ctx->ctx_used_ibrs[0], is_loaded, can_access_pmu));
+ } else {
+ CTX_USED_DBR(ctx, rnum);
+
+ if (can_access_pmu) {
+ ia64_set_dbr(rnum, dbreg.val);
+ ia64_dv_serialize_data();
+ }
+ ctx->ctx_dbrs[rnum] = dbreg.val;
+
+ DPRINT(("write dbr%u=0x%lx used_dbrs=0x%x ld=%d apmu=%d\n",
+ rnum, dbreg.val, ctx->ctx_used_dbrs[0], is_loaded, can_access_pmu));
+ }
+ }
+
+ return 0;
+
+abort_mission:
+ /*
+ * in case it was our first attempt, we undo the global modifications
+ */
+ if (first_time) {
+ LOCK_PFS(flags);
+ if (ctx->ctx_fl_system) {
+ pfm_sessions.pfs_sys_use_dbregs--;
+ }
+ UNLOCK_PFS(flags);
+ ctx->ctx_fl_using_dbreg = 0;
+ }
+ /*
+ * install error return flag
+ */
+ PFM_REG_RETFLAG_SET(req->dbreg_flags, PFM_REG_RETFL_EINVAL);
+
+ return ret;
+}
+
+static int
+pfm_write_ibrs(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+{
+ return pfm_write_ibr_dbr(PFM_CODE_RR, ctx, arg, count, regs);
+}
+
+static int
+pfm_write_dbrs(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+{
+ return pfm_write_ibr_dbr(PFM_DATA_RR, ctx, arg, count, regs);
+}
+
+int
+pfm_mod_write_ibrs(struct task_struct *task, void *req, unsigned int nreq, struct pt_regs *regs)
+{
+ pfm_context_t *ctx;
+
+ if (req == NULL) return -EINVAL;
+
+ ctx = GET_PMU_CTX();
+
+ if (ctx == NULL) return -EINVAL;
+
+ /*
+ * for now limit to current task, which is enough when calling
+ * from overflow handler
+ */
+ if (task != current && ctx->ctx_fl_system == 0) return -EBUSY;
+
+ return pfm_write_ibrs(ctx, req, nreq, regs);
+}
+EXPORT_SYMBOL(pfm_mod_write_ibrs);
+
+int
+pfm_mod_write_dbrs(struct task_struct *task, void *req, unsigned int nreq, struct pt_regs *regs)
+{
+ pfm_context_t *ctx;
+
+ if (req == NULL) return -EINVAL;
+
+ ctx = GET_PMU_CTX();
+
+ if (ctx == NULL) return -EINVAL;
+
+ /*
+ * for now limit to current task, which is enough when calling
+ * from overflow handler
+ */
+ if (task != current && ctx->ctx_fl_system == 0) return -EBUSY;
+
+ return pfm_write_dbrs(ctx, req, nreq, regs);
+}
+EXPORT_SYMBOL(pfm_mod_write_dbrs);
+
+
+static int
+pfm_get_features(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+{
+ pfarg_features_t *req = (pfarg_features_t *)arg;
+
+ req->ft_version = PFM_VERSION;
+ return 0;
+}
+
+static int
+pfm_stop(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+{
+ struct pt_regs *tregs;
+ struct task_struct *task = PFM_CTX_TASK(ctx);
+ int state, is_system;
+
+ state = ctx->ctx_state;
+ is_system = ctx->ctx_fl_system;
+
+ /*
+ * context must be attached to issue the stop command (includes LOADED,MASKED,ZOMBIE)
+ */
+ if (state == PFM_CTX_UNLOADED) return -EINVAL;
+
+ /*
+ * In system wide and when the context is loaded, access can only happen
+ * when the caller is running on the CPU being monitored by the session.
+ * It does not have to be the owner (ctx_task) of the context per se.
+ */
+ if (is_system && ctx->ctx_cpu != smp_processor_id()) {
+ DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu));
+ return -EBUSY;
+ }
+ DPRINT(("task [%d] ctx_state=%d is_system=%d\n",
+ PFM_CTX_TASK(ctx)->pid,
+ state,
+ is_system));
+ /*
+ * in system mode, we need to update the PMU directly
+ * and the user level state of the caller, which may not
+ * necessarily be the creator of the context.
+ */
+ if (is_system) {
+ /*
+ * Update local PMU first
+ *
+ * disable dcr pp
+ */
+ ia64_setreg(_IA64_REG_CR_DCR, ia64_getreg(_IA64_REG_CR_DCR) & ~IA64_DCR_PP);
+ ia64_srlz_i();
+
+ /*
+ * update local cpuinfo
+ */
+ PFM_CPUINFO_CLEAR(PFM_CPUINFO_DCR_PP);
+
+ /*
+ * stop monitoring, does srlz.i
+ */
+ pfm_clear_psr_pp();
+
+ /*
+ * stop monitoring in the caller
+ */
+ ia64_psr(regs)->pp = 0;
+
+ return 0;
+ }
+ /*
+ * per-task mode
+ */
+
+ if (task == current) {
+ /* stop monitoring at kernel level */
+ pfm_clear_psr_up();
+
+ /*
+ * stop monitoring at the user level
+ */
+ ia64_psr(regs)->up = 0;
+ } else {
+ tregs = ia64_task_regs(task);
+
+ /*
+ * stop monitoring at the user level
+ */
+ ia64_psr(tregs)->up = 0;
+
+ /*
+ * monitoring disabled in kernel at next reschedule
+ */
+ ctx->ctx_saved_psr_up = 0;
+ DPRINT(("task=[%d]\n", task->pid));
+ }
+ return 0;
+}
+
+
+static int
+pfm_start(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+{
+ struct pt_regs *tregs;
+ int state, is_system;
+
+ state = ctx->ctx_state;
+ is_system = ctx->ctx_fl_system;
+
+ if (state != PFM_CTX_LOADED) return -EINVAL;
+
+ /*
+ * In system wide and when the context is loaded, access can only happen
+ * when the caller is running on the CPU being monitored by the session.
+ * It does not have to be the owner (ctx_task) of the context per se.
+ */
+ if (is_system && ctx->ctx_cpu != smp_processor_id()) {
+ DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu));
+ return -EBUSY;
+ }
+
+ /*
+ * in system mode, we need to update the PMU directly
+ * and the user level state of the caller, which may not
+ * necessarily be the creator of the context.
+ */
+ if (is_system) {
+
+ /*
+ * set user level psr.pp for the caller
+ */
+ ia64_psr(regs)->pp = 1;
+
+ /*
+ * now update the local PMU and cpuinfo
+ */
+ PFM_CPUINFO_SET(PFM_CPUINFO_DCR_PP);
+
+ /*
+ * start monitoring at kernel level
+ */
+ pfm_set_psr_pp();
+
+ /* enable dcr pp */
+ ia64_setreg(_IA64_REG_CR_DCR, ia64_getreg(_IA64_REG_CR_DCR) | IA64_DCR_PP);
+ ia64_srlz_i();
+
+ return 0;
+ }
+
+ /*
+ * per-process mode
+ */
+
+ if (ctx->ctx_task == current) {
+
+ /* start monitoring at kernel level */
+ pfm_set_psr_up();
+
+ /*
+ * activate monitoring at user level
+ */
+ ia64_psr(regs)->up = 1;
+
+ } else {
+ tregs = ia64_task_regs(ctx->ctx_task);
+
+ /*
+ * start monitoring at the kernel level the next
+ * time the task is scheduled
+ */
+ ctx->ctx_saved_psr_up = IA64_PSR_UP;
+
+ /*
+ * activate monitoring at user level
+ */
+ ia64_psr(tregs)->up = 1;
+ }
+ return 0;
+}
+
+static int
+pfm_get_pmc_reset(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+{
+ pfarg_reg_t *req = (pfarg_reg_t *)arg;
+ unsigned int cnum;
+ int i;
+ int ret = -EINVAL;
+
+ for (i = 0; i < count; i++, req++) {
+
+ cnum = req->reg_num;
+
+ if (!PMC_IS_IMPL(cnum)) goto abort_mission;
+
+ req->reg_value = PMC_DFL_VAL(cnum);
+
+ PFM_REG_RETFLAG_SET(req->reg_flags, 0);
+
+ DPRINT(("pmc_reset_val pmc[%u]=0x%lx\n", cnum, req->reg_value));
+ }
+ return 0;
+
+abort_mission:
+ PFM_REG_RETFLAG_SET(req->reg_flags, PFM_REG_RETFL_EINVAL);
+ return ret;
+}
+
+static int
+pfm_check_task_exist(pfm_context_t *ctx)
+{
+ struct task_struct *g, *t;
+ int ret = -ESRCH;
+
+ read_lock(&tasklist_lock);
+
+ do_each_thread (g, t) {
+ if (t->thread.pfm_context == ctx) {
+ ret = 0;
+ break;
+ }
+ } while_each_thread (g, t);
+
+ read_unlock(&tasklist_lock);
+
+ DPRINT(("pfm_check_task_exist: ret=%d ctx=%p\n", ret, ctx));
+
+ return ret;
+}
+
+static int
+pfm_context_load(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+{
+ struct task_struct *task;
+ struct thread_struct *thread;
+ struct pfm_context_t *old;
+ unsigned long flags;
+#ifndef CONFIG_SMP
+ struct task_struct *owner_task = NULL;
+#endif
+ pfarg_load_t *req = (pfarg_load_t *)arg;
+ unsigned long *pmcs_source, *pmds_source;
+ int the_cpu;
+ int ret = 0;
+ int state, is_system, set_dbregs = 0;
+
+ state = ctx->ctx_state;
+ is_system = ctx->ctx_fl_system;
+ /*
+ * can only load from unloaded or terminated state
+ */
+ if (state != PFM_CTX_UNLOADED) {
+ DPRINT(("cannot load to [%d], invalid ctx_state=%d\n",
+ req->load_pid,
+ ctx->ctx_state));
+ return -EINVAL;
+ }
+
+ DPRINT(("load_pid [%d] using_dbreg=%d\n", req->load_pid, ctx->ctx_fl_using_dbreg));
+
+ if (CTX_OVFL_NOBLOCK(ctx) == 0 && req->load_pid == current->pid) {
+ DPRINT(("cannot use blocking mode on self\n"));
+ return -EINVAL;
+ }
+
+ ret = pfm_get_task(ctx, req->load_pid, &task);
+ if (ret) {
+ DPRINT(("load_pid [%d] get_task=%d\n", req->load_pid, ret));
+ return ret;
+ }
+
+ ret = -EINVAL;
+
+ /*
+ * system wide is self monitoring only
+ */
+ if (is_system && task != current) {
+ DPRINT(("system wide is self monitoring only load_pid=%d\n",
+ req->load_pid));
+ goto error;
+ }
+
+ thread = &task->thread;
+
+ ret = 0;
+ /*
+ * cannot load a context which is using range restrictions,
+ * into a task that is being debugged.
+ */
+ if (ctx->ctx_fl_using_dbreg) {
+ if (thread->flags & IA64_THREAD_DBG_VALID) {
+ ret = -EBUSY;
+ DPRINT(("load_pid [%d] task is debugged, cannot load range restrictions\n", req->load_pid));
+ goto error;
+ }
+ LOCK_PFS(flags);
+
+ if (is_system) {
+ if (pfm_sessions.pfs_ptrace_use_dbregs) {
+ DPRINT(("cannot load [%d] dbregs in use\n", task->pid));
+ ret = -EBUSY;
+ } else {
+ pfm_sessions.pfs_sys_use_dbregs++;
+ DPRINT(("load [%d] increased sys_use_dbreg=%u\n", task->pid, pfm_sessions.pfs_sys_use_dbregs));
+ set_dbregs = 1;
+ }
+ }
+
+ UNLOCK_PFS(flags);
+
+ if (ret) goto error;
+ }
+
+ /*
+ * SMP system-wide monitoring implies self-monitoring.
+ *
+ * The programming model expects the task to
+ * be pinned on a CPU throughout the session.
+ * Here we take note of the current CPU at the
+ * time the context is loaded. No call from
+ * another CPU will be allowed.
+ *
+ * The pinning via shed_setaffinity()
+ * must be done by the calling task prior
+ * to this call.
+ *
+ * systemwide: keep track of CPU this session is supposed to run on
+ */
+ the_cpu = ctx->ctx_cpu = smp_processor_id();
+
+ ret = -EBUSY;
+ /*
+ * now reserve the session
+ */
+ ret = pfm_reserve_session(current, is_system, the_cpu);
+ if (ret) goto error;
+
+ /*
+ * task is necessarily stopped at this point.
+ *
+ * If the previous context was zombie, then it got removed in
+ * pfm_save_regs(). Therefore we should not see it here.
+ * If we see a context, then this is an active context
+ *
+ * XXX: needs to be atomic
+ */
+ DPRINT(("before cmpxchg() old_ctx=%p new_ctx=%p\n",
+ thread->pfm_context, ctx));
+
+ old = ia64_cmpxchg(acq, &thread->pfm_context, NULL, ctx, sizeof(pfm_context_t *));
+ if (old != NULL) {
+ DPRINT(("load_pid [%d] already has a context\n", req->load_pid));
+ goto error_unres;
+ }
+
+ pfm_reset_msgq(ctx);
+
+ ctx->ctx_state = PFM_CTX_LOADED;
+
+ /*
+ * link context to task
+ */
+ ctx->ctx_task = task;
+
+ if (is_system) {
+ /*
+ * we load as stopped
+ */
+ PFM_CPUINFO_SET(PFM_CPUINFO_SYST_WIDE);
+ PFM_CPUINFO_CLEAR(PFM_CPUINFO_DCR_PP);
+
+ if (ctx->ctx_fl_excl_idle) PFM_CPUINFO_SET(PFM_CPUINFO_EXCL_IDLE);
+ } else {
+ thread->flags |= IA64_THREAD_PM_VALID;
+ }
+
+ /*
+ * propagate into thread-state
+ */
+ pfm_copy_pmds(task, ctx);
+ pfm_copy_pmcs(task, ctx);
+
+ pmcs_source = thread->pmcs;
+ pmds_source = thread->pmds;
+
+ /*
+ * always the case for system-wide
+ */
+ if (task == current) {
+
+ if (is_system == 0) {
+
+ /* allow user level control */
+ ia64_psr(regs)->sp = 0;
+ DPRINT(("clearing psr.sp for [%d]\n", task->pid));
+
+ SET_LAST_CPU(ctx, smp_processor_id());
+ INC_ACTIVATION();
+ SET_ACTIVATION(ctx);
+#ifndef CONFIG_SMP
+ /*
+ * push the other task out, if any
+ */
+ owner_task = GET_PMU_OWNER();
+ if (owner_task) pfm_lazy_save_regs(owner_task);
+#endif
+ }
+ /*
+ * load all PMD from ctx to PMU (as opposed to thread state)
+ * restore all PMC from ctx to PMU
+ */
+ pfm_restore_pmds(pmds_source, ctx->ctx_all_pmds[0]);
+ pfm_restore_pmcs(pmcs_source, ctx->ctx_all_pmcs[0]);
+
+ ctx->ctx_reload_pmcs[0] = 0UL;
+ ctx->ctx_reload_pmds[0] = 0UL;
+
+ /*
+ * guaranteed safe by earlier check against DBG_VALID
+ */
+ if (ctx->ctx_fl_using_dbreg) {
+ pfm_restore_ibrs(ctx->ctx_ibrs, pmu_conf->num_ibrs);
+ pfm_restore_dbrs(ctx->ctx_dbrs, pmu_conf->num_dbrs);
+ }
+ /*
+ * set new ownership
+ */
+ SET_PMU_OWNER(task, ctx);
+
+ DPRINT(("context loaded on PMU for [%d]\n", task->pid));
+ } else {
+ /*
+ * when not current, task MUST be stopped, so this is safe
+ */
+ regs = ia64_task_regs(task);
+
+ /* force a full reload */
+ ctx->ctx_last_activation = PFM_INVALID_ACTIVATION;
+ SET_LAST_CPU(ctx, -1);
+
+ /* initial saved psr (stopped) */
+ ctx->ctx_saved_psr_up = 0UL;
+ ia64_psr(regs)->up = ia64_psr(regs)->pp = 0;
+ }
+
+ ret = 0;
+
+error_unres:
+ if (ret) pfm_unreserve_session(ctx, ctx->ctx_fl_system, the_cpu);
+error:
+ /*
+ * we must undo the dbregs setting (for system-wide)
+ */
+ if (ret && set_dbregs) {
+ LOCK_PFS(flags);
+ pfm_sessions.pfs_sys_use_dbregs--;
+ UNLOCK_PFS(flags);
+ }
+ /*
+ * release task, there is now a link with the context
+ */
+ if (is_system == 0 && task != current) {
+ pfm_put_task(task);
+
+ if (ret == 0) {
+ ret = pfm_check_task_exist(ctx);
+ if (ret) {
+ ctx->ctx_state = PFM_CTX_UNLOADED;
+ ctx->ctx_task = NULL;
+ }
+ }
+ }
+ return ret;
+}
+
+/*
+ * in this function, we do not need to increase the use count
+ * for the task via get_task_struct(), because we hold the
+ * context lock. If the task were to disappear while having
+ * a context attached, it would go through pfm_exit_thread()
+ * which also grabs the context lock and would therefore be blocked
+ * until we are here.
+ */
+static void pfm_flush_pmds(struct task_struct *, pfm_context_t *ctx);
+
+static int
+pfm_context_unload(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
+{
+ struct task_struct *task = PFM_CTX_TASK(ctx);
+ struct pt_regs *tregs;
+ int prev_state, is_system;
+ int ret;
+
+ DPRINT(("ctx_state=%d task [%d]\n", ctx->ctx_state, task ? task->pid : -1));
+
+ prev_state = ctx->ctx_state;
+ is_system = ctx->ctx_fl_system;
+
+ /*
+ * unload only when necessary
+ */
+ if (prev_state == PFM_CTX_UNLOADED) {
+ DPRINT(("ctx_state=%d, nothing to do\n", prev_state));
+ return 0;
+ }
+
+ /*
+ * clear psr and dcr bits
+ */
+ ret = pfm_stop(ctx, NULL, 0, regs);
+ if (ret) return ret;
+
+ ctx->ctx_state = PFM_CTX_UNLOADED;
+
+ /*
+ * in system mode, we need to update the PMU directly
+ * and the user level state of the caller, which may not
+ * necessarily be the creator of the context.
+ */
+ if (is_system) {
+
+ /*
+ * Update cpuinfo
+ *
+ * local PMU is taken care of in pfm_stop()
+ */
+ PFM_CPUINFO_CLEAR(PFM_CPUINFO_SYST_WIDE);
+ PFM_CPUINFO_CLEAR(PFM_CPUINFO_EXCL_IDLE);
+
+ /*
+ * save PMDs in context
+ * release ownership
+ */
+ pfm_flush_pmds(current, ctx);
+
+ /*
+ * at this point we are done with the PMU
+ * so we can unreserve the resource.
+ */
+ if (prev_state != PFM_CTX_ZOMBIE)
+ pfm_unreserve_session(ctx, 1 , ctx->ctx_cpu);
+
+ /*
+ * disconnect context from task
+ */
+ task->thread.pfm_context = NULL;
+ /*
+ * disconnect task from context
+ */
+ ctx->ctx_task = NULL;
+
+ /*
+ * There is nothing more to cleanup here.
+ */
+ return 0;
+ }
+
+ /*
+ * per-task mode
+ */
+ tregs = task == current ? regs : ia64_task_regs(task);
+
+ if (task == current) {
+ /*
+ * cancel user level control
+ */
+ ia64_psr(regs)->sp = 1;
+
+ DPRINT(("setting psr.sp for [%d]\n", task->pid));
+ }
+ /*
+ * save PMDs to context
+ * release ownership
+ */
+ pfm_flush_pmds(task, ctx);
+
+ /*
+ * at this point we are done with the PMU
+ * so we can unreserve the resource.
+ *
+ * when state was ZOMBIE, we have already unreserved.
+ */
+ if (prev_state != PFM_CTX_ZOMBIE)
+ pfm_unreserve_session(ctx, 0 , ctx->ctx_cpu);
+
+ /*
+ * reset activation counter and psr
+ */
+ ctx->ctx_last_activation = PFM_INVALID_ACTIVATION;
+ SET_LAST_CPU(ctx, -1);
+
+ /*
+ * PMU state will not be restored
+ */
+ task->thread.flags &= ~IA64_THREAD_PM_VALID;
+
+ /*
+ * break links between context and task
+ */
+ task->thread.pfm_context = NULL;
+ ctx->ctx_task = NULL;
+
+ PFM_SET_WORK_PENDING(task, 0);
+
+ ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_NONE;
+ ctx->ctx_fl_can_restart = 0;
+ ctx->ctx_fl_going_zombie = 0;
+
+ DPRINT(("disconnected [%d] from context\n", task->pid));
+
+ return 0;
+}
+
+
+/*
+ * called only from exit_thread(): task == current
+ * we come here only if current has a context attached (loaded or masked)
+ */
+void
+pfm_exit_thread(struct task_struct *task)
+{
+ pfm_context_t *ctx;
+ unsigned long flags;
+ struct pt_regs *regs = ia64_task_regs(task);
+ int ret, state;
+ int free_ok = 0;
+
+ ctx = PFM_GET_CTX(task);
+
+ PROTECT_CTX(ctx, flags);
+
+ DPRINT(("state=%d task [%d]\n", ctx->ctx_state, task->pid));
+
+ state = ctx->ctx_state;
+ switch(state) {
+ case PFM_CTX_UNLOADED:
+ /*
+ * only comes to thios function if pfm_context is not NULL, i.e., cannot
+ * be in unloaded state
+ */
+ printk(KERN_ERR "perfmon: pfm_exit_thread [%d] ctx unloaded\n", task->pid);
+ break;
+ case PFM_CTX_LOADED:
+ case PFM_CTX_MASKED:
+ ret = pfm_context_unload(ctx, NULL, 0, regs);
+ if (ret) {
+ printk(KERN_ERR "perfmon: pfm_exit_thread [%d] state=%d unload failed %d\n", task->pid, state, ret);
+ }
+ DPRINT(("ctx unloaded for current state was %d\n", state));
+
+ pfm_end_notify_user(ctx);
+ break;
+ case PFM_CTX_ZOMBIE:
+ ret = pfm_context_unload(ctx, NULL, 0, regs);
+ if (ret) {
+ printk(KERN_ERR "perfmon: pfm_exit_thread [%d] state=%d unload failed %d\n", task->pid, state, ret);
+ }
+ free_ok = 1;
+ break;
+ default:
+ printk(KERN_ERR "perfmon: pfm_exit_thread [%d] unexpected state=%d\n", task->pid, state);
+ break;
+ }
+ UNPROTECT_CTX(ctx, flags);
+
+ { u64 psr = pfm_get_psr();
+ BUG_ON(psr & (IA64_PSR_UP|IA64_PSR_PP));
+ BUG_ON(GET_PMU_OWNER());
+ BUG_ON(ia64_psr(regs)->up);
+ BUG_ON(ia64_psr(regs)->pp);
+ }
+
+ /*
+ * All memory free operations (especially for vmalloc'ed memory)
+ * MUST be done with interrupts ENABLED.
+ */
+ if (free_ok) pfm_context_free(ctx);
+}
+
+/*
+ * functions MUST be listed in the increasing order of their index (see permfon.h)
+ */
+#define PFM_CMD(name, flags, arg_count, arg_type, getsz) { name, #name, flags, arg_count, sizeof(arg_type), getsz }
+#define PFM_CMD_S(name, flags) { name, #name, flags, 0, 0, NULL }
+#define PFM_CMD_PCLRWS (PFM_CMD_FD|PFM_CMD_ARG_RW|PFM_CMD_STOP)
+#define PFM_CMD_PCLRW (PFM_CMD_FD|PFM_CMD_ARG_RW)
+#define PFM_CMD_NONE { NULL, "no-cmd", 0, 0, 0, NULL}
+
+static pfm_cmd_desc_t pfm_cmd_tab[]={
+/* 0 */PFM_CMD_NONE,
+/* 1 */PFM_CMD(pfm_write_pmcs, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_reg_t, NULL),
+/* 2 */PFM_CMD(pfm_write_pmds, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_reg_t, NULL),
+/* 3 */PFM_CMD(pfm_read_pmds, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_reg_t, NULL),
+/* 4 */PFM_CMD_S(pfm_stop, PFM_CMD_PCLRWS),
+/* 5 */PFM_CMD_S(pfm_start, PFM_CMD_PCLRWS),
+/* 6 */PFM_CMD_NONE,
+/* 7 */PFM_CMD_NONE,
+/* 8 */PFM_CMD(pfm_context_create, PFM_CMD_ARG_RW, 1, pfarg_context_t, pfm_ctx_getsize),
+/* 9 */PFM_CMD_NONE,
+/* 10 */PFM_CMD_S(pfm_restart, PFM_CMD_PCLRW),
+/* 11 */PFM_CMD_NONE,
+/* 12 */PFM_CMD(pfm_get_features, PFM_CMD_ARG_RW, 1, pfarg_features_t, NULL),
+/* 13 */PFM_CMD(pfm_debug, 0, 1, unsigned int, NULL),
+/* 14 */PFM_CMD_NONE,
+/* 15 */PFM_CMD(pfm_get_pmc_reset, PFM_CMD_ARG_RW, PFM_CMD_ARG_MANY, pfarg_reg_t, NULL),
+/* 16 */PFM_CMD(pfm_context_load, PFM_CMD_PCLRWS, 1, pfarg_load_t, NULL),
+/* 17 */PFM_CMD_S(pfm_context_unload, PFM_CMD_PCLRWS),
+/* 18 */PFM_CMD_NONE,
+/* 19 */PFM_CMD_NONE,
+/* 20 */PFM_CMD_NONE,
+/* 21 */PFM_CMD_NONE,
+/* 22 */PFM_CMD_NONE,
+/* 23 */PFM_CMD_NONE,
+/* 24 */PFM_CMD_NONE,
+/* 25 */PFM_CMD_NONE,
+/* 26 */PFM_CMD_NONE,
+/* 27 */PFM_CMD_NONE,
+/* 28 */PFM_CMD_NONE,
+/* 29 */PFM_CMD_NONE,
+/* 30 */PFM_CMD_NONE,
+/* 31 */PFM_CMD_NONE,
+/* 32 */PFM_CMD(pfm_write_ibrs, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_dbreg_t, NULL),
+/* 33 */PFM_CMD(pfm_write_dbrs, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_dbreg_t, NULL)
+};
+#define PFM_CMD_COUNT (sizeof(pfm_cmd_tab)/sizeof(pfm_cmd_desc_t))
+
+static int
+pfm_check_task_state(pfm_context_t *ctx, int cmd, unsigned long flags)
+{
+ struct task_struct *task;
+ int state, old_state;
+
+recheck:
+ state = ctx->ctx_state;
+ task = ctx->ctx_task;
+
+ if (task == NULL) {
+ DPRINT(("context %d no task, state=%d\n", ctx->ctx_fd, state));
+ return 0;
+ }
+
+ DPRINT(("context %d state=%d [%d] task_state=%ld must_stop=%d\n",
+ ctx->ctx_fd,
+ state,
+ task->pid,
+ task->state, PFM_CMD_STOPPED(cmd)));
+
+ /*
+ * self-monitoring always ok.
+ *
+ * for system-wide the caller can either be the creator of the
+ * context (to one to which the context is attached to) OR
+ * a task running on the same CPU as the session.
+ */
+ if (task == current || ctx->ctx_fl_system) return 0;
+
+ /*
+ * if context is UNLOADED we are safe to go
+ */
+ if (state == PFM_CTX_UNLOADED) return 0;
+
+ /*
+ * no command can operate on a zombie context
+ */
+ if (state == PFM_CTX_ZOMBIE) {
+ DPRINT(("cmd %d state zombie cannot operate on context\n", cmd));
+ return -EINVAL;
+ }
+
+ /*
+ * context is LOADED or MASKED. Some commands may need to have
+ * the task stopped.
+ *
+ * We could lift this restriction for UP but it would mean that
+ * the user has no guarantee the task would not run between
+ * two successive calls to perfmonctl(). That's probably OK.
+ * If this user wants to ensure the task does not run, then
+ * the task must be stopped.
+ */
+ if (PFM_CMD_STOPPED(cmd)) {
+ if ((task->state != TASK_STOPPED) && (task->state != TASK_TRACED)) {
+ DPRINT(("[%d] task not in stopped state\n", task->pid));
+ return -EBUSY;
+ }
+ /*
+ * task is now stopped, wait for ctxsw out
+ *
+ * This is an interesting point in the code.
+ * We need to unprotect the context because
+ * the pfm_save_regs() routines needs to grab
+ * the same lock. There are danger in doing
+ * this because it leaves a window open for
+ * another task to get access to the context
+ * and possibly change its state. The one thing
+ * that is not possible is for the context to disappear
+ * because we are protected by the VFS layer, i.e.,
+ * get_fd()/put_fd().
+ */
+ old_state = state;
+
+ UNPROTECT_CTX(ctx, flags);
+
+ wait_task_inactive(task);
+
+ PROTECT_CTX(ctx, flags);
+
+ /*
+ * we must recheck to verify if state has changed
+ */
+ if (ctx->ctx_state != old_state) {
+ DPRINT(("old_state=%d new_state=%d\n", old_state, ctx->ctx_state));
+ goto recheck;
+ }
+ }
+ return 0;
+}
+
+/*
+ * system-call entry point (must return long)
+ */
+asmlinkage long
+sys_perfmonctl (int fd, int cmd, void __user *arg, int count)
+{
+ struct file *file = NULL;
+ pfm_context_t *ctx = NULL;
+ unsigned long flags = 0UL;
+ void *args_k = NULL;
+ long ret; /* will expand int return types */
+ size_t base_sz, sz, xtra_sz = 0;
+ int narg, completed_args = 0, call_made = 0, cmd_flags;
+ int (*func)(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs);
+ int (*getsize)(void *arg, size_t *sz);
+#define PFM_MAX_ARGSIZE 4096
+
+ /*
+ * reject any call if perfmon was disabled at initialization
+ */
+ if (unlikely(pmu_conf == NULL)) return -ENOSYS;
+
+ if (unlikely(cmd < 0 || cmd >= PFM_CMD_COUNT)) {
+ DPRINT(("invalid cmd=%d\n", cmd));
+ return -EINVAL;
+ }
+
+ func = pfm_cmd_tab[cmd].cmd_func;
+ narg = pfm_cmd_tab[cmd].cmd_narg;
+ base_sz = pfm_cmd_tab[cmd].cmd_argsize;
+ getsize = pfm_cmd_tab[cmd].cmd_getsize;
+ cmd_flags = pfm_cmd_tab[cmd].cmd_flags;
+
+ if (unlikely(func == NULL)) {
+ DPRINT(("invalid cmd=%d\n", cmd));
+ return -EINVAL;
+ }
+
+ DPRINT(("cmd=%s idx=%d narg=0x%x argsz=%lu count=%d\n",
+ PFM_CMD_NAME(cmd),
+ cmd,
+ narg,
+ base_sz,
+ count));
+
+ /*
+ * check if number of arguments matches what the command expects
+ */
+ if (unlikely((narg == PFM_CMD_ARG_MANY && count <= 0) || (narg > 0 && narg != count)))
+ return -EINVAL;
+
+restart_args:
+ sz = xtra_sz + base_sz*count;
+ /*
+ * limit abuse to min page size
+ */
+ if (unlikely(sz > PFM_MAX_ARGSIZE)) {
+ printk(KERN_ERR "perfmon: [%d] argument too big %lu\n", current->pid, sz);
+ return -E2BIG;
+ }
+
+ /*
+ * allocate default-sized argument buffer
+ */
+ if (likely(count && args_k == NULL)) {
+ args_k = kmalloc(PFM_MAX_ARGSIZE, GFP_KERNEL);
+ if (args_k == NULL) return -ENOMEM;
+ }
+
+ ret = -EFAULT;
+
+ /*
+ * copy arguments
+ *
+ * assume sz = 0 for command without parameters
+ */
+ if (sz && copy_from_user(args_k, arg, sz)) {
+ DPRINT(("cannot copy_from_user %lu bytes @%p\n", sz, arg));
+ goto error_args;
+ }
+
+ /*
+ * check if command supports extra parameters
+ */
+ if (completed_args == 0 && getsize) {
+ /*
+ * get extra parameters size (based on main argument)
+ */
+ ret = (*getsize)(args_k, &xtra_sz);
+ if (ret) goto error_args;
+
+ completed_args = 1;
+
+ DPRINT(("restart_args sz=%lu xtra_sz=%lu\n", sz, xtra_sz));
+
+ /* retry if necessary */
+ if (likely(xtra_sz)) goto restart_args;
+ }
+
+ if (unlikely((cmd_flags & PFM_CMD_FD) == 0)) goto skip_fd;
+
+ ret = -EBADF;
+
+ file = fget(fd);
+ if (unlikely(file == NULL)) {
+ DPRINT(("invalid fd %d\n", fd));
+ goto error_args;
+ }
+ if (unlikely(PFM_IS_FILE(file) == 0)) {
+ DPRINT(("fd %d not related to perfmon\n", fd));
+ goto error_args;
+ }
+
+ ctx = (pfm_context_t *)file->private_data;
+ if (unlikely(ctx == NULL)) {
+ DPRINT(("no context for fd %d\n", fd));
+ goto error_args;
+ }
+ prefetch(&ctx->ctx_state);
+
+ PROTECT_CTX(ctx, flags);
+
+ /*
+ * check task is stopped
+ */
+ ret = pfm_check_task_state(ctx, cmd, flags);
+ if (unlikely(ret)) goto abort_locked;
+
+skip_fd:
+ ret = (*func)(ctx, args_k, count, ia64_task_regs(current));
+
+ call_made = 1;
+
+abort_locked:
+ if (likely(ctx)) {
+ DPRINT(("context unlocked\n"));
+ UNPROTECT_CTX(ctx, flags);
+ fput(file);
+ }
+
+ /* copy argument back to user, if needed */
+ if (call_made && PFM_CMD_RW_ARG(cmd) && copy_to_user(arg, args_k, base_sz*count)) ret = -EFAULT;
+
+error_args:
+ if (args_k) kfree(args_k);
+
+ DPRINT(("cmd=%s ret=%ld\n", PFM_CMD_NAME(cmd), ret));
+
+ return ret;
+}
+
+static void
+pfm_resume_after_ovfl(pfm_context_t *ctx, unsigned long ovfl_regs, struct pt_regs *regs)
+{
+ pfm_buffer_fmt_t *fmt = ctx->ctx_buf_fmt;
+ pfm_ovfl_ctrl_t rst_ctrl;
+ int state;
+ int ret = 0;
+
+ state = ctx->ctx_state;
+ /*
+ * Unlock sampling buffer and reset index atomically
+ * XXX: not really needed when blocking
+ */
+ if (CTX_HAS_SMPL(ctx)) {
+
+ rst_ctrl.bits.mask_monitoring = 0;
+ rst_ctrl.bits.reset_ovfl_pmds = 0;
+
+ if (state == PFM_CTX_LOADED)
+ ret = pfm_buf_fmt_restart_active(fmt, current, &rst_ctrl, ctx->ctx_smpl_hdr, regs);
+ else
+ ret = pfm_buf_fmt_restart(fmt, current, &rst_ctrl, ctx->ctx_smpl_hdr, regs);
+ } else {
+ rst_ctrl.bits.mask_monitoring = 0;
+ rst_ctrl.bits.reset_ovfl_pmds = 1;
+ }
+
+ if (ret == 0) {
+ if (rst_ctrl.bits.reset_ovfl_pmds) {
+ pfm_reset_regs(ctx, &ovfl_regs, PFM_PMD_LONG_RESET);
+ }
+ if (rst_ctrl.bits.mask_monitoring == 0) {
+ DPRINT(("resuming monitoring\n"));
+ if (ctx->ctx_state == PFM_CTX_MASKED) pfm_restore_monitoring(current);
+ } else {
+ DPRINT(("stopping monitoring\n"));
+ //pfm_stop_monitoring(current, regs);
+ }
+ ctx->ctx_state = PFM_CTX_LOADED;
+ }
+}
+
+/*
+ * context MUST BE LOCKED when calling
+ * can only be called for current
+ */
+static void
+pfm_context_force_terminate(pfm_context_t *ctx, struct pt_regs *regs)
+{
+ int ret;
+
+ DPRINT(("entering for [%d]\n", current->pid));
+
+ ret = pfm_context_unload(ctx, NULL, 0, regs);
+ if (ret) {
+ printk(KERN_ERR "pfm_context_force_terminate: [%d] unloaded failed with %d\n", current->pid, ret);
+ }
+
+ /*
+ * and wakeup controlling task, indicating we are now disconnected
+ */
+ wake_up_interruptible(&ctx->ctx_zombieq);
+
+ /*
+ * given that context is still locked, the controlling
+ * task will only get access when we return from
+ * pfm_handle_work().
+ */
+}
+
+static int pfm_ovfl_notify_user(pfm_context_t *ctx, unsigned long ovfl_pmds);
+
+void
+pfm_handle_work(void)
+{
+ pfm_context_t *ctx;
+ struct pt_regs *regs;
+ unsigned long flags;
+ unsigned long ovfl_regs;
+ unsigned int reason;
+ int ret;
+
+ ctx = PFM_GET_CTX(current);
+ if (ctx == NULL) {
+ printk(KERN_ERR "perfmon: [%d] has no PFM context\n", current->pid);
+ return;
+ }
+
+ PROTECT_CTX(ctx, flags);
+
+ PFM_SET_WORK_PENDING(current, 0);
+
+ pfm_clear_task_notify();
+
+ regs = ia64_task_regs(current);
+
+ /*
+ * extract reason for being here and clear
+ */
+ reason = ctx->ctx_fl_trap_reason;
+ ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_NONE;
+ ovfl_regs = ctx->ctx_ovfl_regs[0];
+
+ DPRINT(("reason=%d state=%d\n", reason, ctx->ctx_state));
+
+ /*
+ * must be done before we check for simple-reset mode
+ */
+ if (ctx->ctx_fl_going_zombie || ctx->ctx_state == PFM_CTX_ZOMBIE) goto do_zombie;
+
+
+ //if (CTX_OVFL_NOBLOCK(ctx)) goto skip_blocking;
+ if (reason == PFM_TRAP_REASON_RESET) goto skip_blocking;
+
+ UNPROTECT_CTX(ctx, flags);
+
+ /*
+ * pfm_handle_work() is currently called with interrupts disabled.
+ * The down_interruptible call may sleep, therefore we
+ * must re-enable interrupts to avoid deadlocks. It is
+ * safe to do so because this function is called ONLY
+ * when returning to user level (PUStk=1), in which case
+ * there is no risk of kernel stack overflow due to deep
+ * interrupt nesting.
+ */
+ BUG_ON(flags & IA64_PSR_I);
+ local_irq_enable();
+
+ DPRINT(("before block sleeping\n"));
+
+ /*
+ * may go through without blocking on SMP systems
+ * if restart has been received already by the time we call down()
+ */
+ ret = down_interruptible(&ctx->ctx_restart_sem);
+
+ DPRINT(("after block sleeping ret=%d\n", ret));
+
+ /*
+ * disable interrupts to restore state we had upon entering
+ * this function
+ */
+ local_irq_disable();
+
+ PROTECT_CTX(ctx, flags);
+
+ /*
+ * we need to read the ovfl_regs only after wake-up
+ * because we may have had pfm_write_pmds() in between
+ * and that can changed PMD values and therefore
+ * ovfl_regs is reset for these new PMD values.
+ */
+ ovfl_regs = ctx->ctx_ovfl_regs[0];
+
+ if (ctx->ctx_fl_going_zombie) {
+do_zombie:
+ DPRINT(("context is zombie, bailing out\n"));
+ pfm_context_force_terminate(ctx, regs);
+ goto nothing_to_do;
+ }
+ /*
+ * in case of interruption of down() we don't restart anything
+ */
+ if (ret < 0) goto nothing_to_do;
+
+skip_blocking:
+ pfm_resume_after_ovfl(ctx, ovfl_regs, regs);
+ ctx->ctx_ovfl_regs[0] = 0UL;
+
+nothing_to_do:
+
+ UNPROTECT_CTX(ctx, flags);
+}
+
+static int
+pfm_notify_user(pfm_context_t *ctx, pfm_msg_t *msg)
+{
+ if (ctx->ctx_state == PFM_CTX_ZOMBIE) {
+ DPRINT(("ignoring overflow notification, owner is zombie\n"));
+ return 0;
+ }
+
+ DPRINT(("waking up somebody\n"));
+
+ if (msg) wake_up_interruptible(&ctx->ctx_msgq_wait);
+
+ /*
+ * safe, we are not in intr handler, nor in ctxsw when
+ * we come here
+ */
+ kill_fasync (&ctx->ctx_async_queue, SIGIO, POLL_IN);
+
+ return 0;
+}
+
+static int
+pfm_ovfl_notify_user(pfm_context_t *ctx, unsigned long ovfl_pmds)
+{
+ pfm_msg_t *msg = NULL;
+
+ if (ctx->ctx_fl_no_msg == 0) {
+ msg = pfm_get_new_msg(ctx);
+ if (msg == NULL) {
+ printk(KERN_ERR "perfmon: pfm_ovfl_notify_user no more notification msgs\n");
+ return -1;
+ }
+
+ msg->pfm_ovfl_msg.msg_type = PFM_MSG_OVFL;
+ msg->pfm_ovfl_msg.msg_ctx_fd = ctx->ctx_fd;
+ msg->pfm_ovfl_msg.msg_active_set = 0;
+ msg->pfm_ovfl_msg.msg_ovfl_pmds[0] = ovfl_pmds;
+ msg->pfm_ovfl_msg.msg_ovfl_pmds[1] = 0UL;
+ msg->pfm_ovfl_msg.msg_ovfl_pmds[2] = 0UL;
+ msg->pfm_ovfl_msg.msg_ovfl_pmds[3] = 0UL;
+ msg->pfm_ovfl_msg.msg_tstamp = 0UL;
+ }
+
+ DPRINT(("ovfl msg: msg=%p no_msg=%d fd=%d ovfl_pmds=0x%lx\n",
+ msg,
+ ctx->ctx_fl_no_msg,
+ ctx->ctx_fd,
+ ovfl_pmds));
+
+ return pfm_notify_user(ctx, msg);
+}
+
+static int
+pfm_end_notify_user(pfm_context_t *ctx)
+{
+ pfm_msg_t *msg;
+
+ msg = pfm_get_new_msg(ctx);
+ if (msg == NULL) {
+ printk(KERN_ERR "perfmon: pfm_end_notify_user no more notification msgs\n");
+ return -1;
+ }
+ /* no leak */
+ memset(msg, 0, sizeof(*msg));
+
+ msg->pfm_end_msg.msg_type = PFM_MSG_END;
+ msg->pfm_end_msg.msg_ctx_fd = ctx->ctx_fd;
+ msg->pfm_ovfl_msg.msg_tstamp = 0UL;
+
+ DPRINT(("end msg: msg=%p no_msg=%d ctx_fd=%d\n",
+ msg,
+ ctx->ctx_fl_no_msg,
+ ctx->ctx_fd));
+
+ return pfm_notify_user(ctx, msg);
+}
+
+/*
+ * main overflow processing routine.
+ * it can be called from the interrupt path or explicitely during the context switch code
+ */
+static void
+pfm_overflow_handler(struct task_struct *task, pfm_context_t *ctx, u64 pmc0, struct pt_regs *regs)
+{
+ pfm_ovfl_arg_t *ovfl_arg;
+ unsigned long mask;
+ unsigned long old_val, ovfl_val, new_val;
+ unsigned long ovfl_notify = 0UL, ovfl_pmds = 0UL, smpl_pmds = 0UL, reset_pmds;
+ unsigned long tstamp;
+ pfm_ovfl_ctrl_t ovfl_ctrl;
+ unsigned int i, has_smpl;
+ int must_notify = 0;
+
+ if (unlikely(ctx->ctx_state == PFM_CTX_ZOMBIE)) goto stop_monitoring;
+
+ /*
+ * sanity test. Should never happen
+ */
+ if (unlikely((pmc0 & 0x1) == 0)) goto sanity_check;
+
+ tstamp = ia64_get_itc();
+ mask = pmc0 >> PMU_FIRST_COUNTER;
+ ovfl_val = pmu_conf->ovfl_val;
+ has_smpl = CTX_HAS_SMPL(ctx);
+
+ DPRINT_ovfl(("pmc0=0x%lx pid=%d iip=0x%lx, %s "
+ "used_pmds=0x%lx\n",
+ pmc0,
+ task ? task->pid: -1,
+ (regs ? regs->cr_iip : 0),
+ CTX_OVFL_NOBLOCK(ctx) ? "nonblocking" : "blocking",
+ ctx->ctx_used_pmds[0]));
+
+
+ /*
+ * first we update the virtual counters
+ * assume there was a prior ia64_srlz_d() issued
+ */
+ for (i = PMU_FIRST_COUNTER; mask ; i++, mask >>= 1) {
+
+ /* skip pmd which did not overflow */
+ if ((mask & 0x1) == 0) continue;
+
+ /*
+ * Note that the pmd is not necessarily 0 at this point as qualified events
+ * may have happened before the PMU was frozen. The residual count is not
+ * taken into consideration here but will be with any read of the pmd via
+ * pfm_read_pmds().
+ */
+ old_val = new_val = ctx->ctx_pmds[i].val;
+ new_val += 1 + ovfl_val;
+ ctx->ctx_pmds[i].val = new_val;
+
+ /*
+ * check for overflow condition
+ */
+ if (likely(old_val > new_val)) {
+ ovfl_pmds |= 1UL << i;
+ if (PMC_OVFL_NOTIFY(ctx, i)) ovfl_notify |= 1UL << i;
+ }
+
+ DPRINT_ovfl(("ctx_pmd[%d].val=0x%lx old_val=0x%lx pmd=0x%lx ovfl_pmds=0x%lx ovfl_notify=0x%lx\n",
+ i,
+ new_val,
+ old_val,
+ ia64_get_pmd(i) & ovfl_val,
+ ovfl_pmds,
+ ovfl_notify));
+ }
+
+ /*
+ * there was no 64-bit overflow, nothing else to do
+ */
+ if (ovfl_pmds == 0UL) return;
+
+ /*
+ * reset all control bits
+ */
+ ovfl_ctrl.val = 0;
+ reset_pmds = 0UL;
+
+ /*
+ * if a sampling format module exists, then we "cache" the overflow by
+ * calling the module's handler() routine.
+ */
+ if (has_smpl) {
+ unsigned long start_cycles, end_cycles;
+ unsigned long pmd_mask;
+ int j, k, ret = 0;
+ int this_cpu = smp_processor_id();
+
+ pmd_mask = ovfl_pmds >> PMU_FIRST_COUNTER;
+ ovfl_arg = &ctx->ctx_ovfl_arg;
+
+ prefetch(ctx->ctx_smpl_hdr);
+
+ for(i=PMU_FIRST_COUNTER; pmd_mask && ret == 0; i++, pmd_mask >>=1) {
+
+ mask = 1UL << i;
+
+ if ((pmd_mask & 0x1) == 0) continue;
+
+ ovfl_arg->ovfl_pmd = (unsigned char )i;
+ ovfl_arg->ovfl_notify = ovfl_notify & mask ? 1 : 0;
+ ovfl_arg->active_set = 0;
+ ovfl_arg->ovfl_ctrl.val = 0; /* module must fill in all fields */
+ ovfl_arg->smpl_pmds[0] = smpl_pmds = ctx->ctx_pmds[i].smpl_pmds[0];
+
+ ovfl_arg->pmd_value = ctx->ctx_pmds[i].val;
+ ovfl_arg->pmd_last_reset = ctx->ctx_pmds[i].lval;
+ ovfl_arg->pmd_eventid = ctx->ctx_pmds[i].eventid;
+
+ /*
+ * copy values of pmds of interest. Sampling format may copy them
+ * into sampling buffer.
+ */
+ if (smpl_pmds) {
+ for(j=0, k=0; smpl_pmds; j++, smpl_pmds >>=1) {
+ if ((smpl_pmds & 0x1) == 0) continue;
+ ovfl_arg->smpl_pmds_values[k++] = PMD_IS_COUNTING(j) ? pfm_read_soft_counter(ctx, j) : ia64_get_pmd(j);
+ DPRINT_ovfl(("smpl_pmd[%d]=pmd%u=0x%lx\n", k-1, j, ovfl_arg->smpl_pmds_values[k-1]));
+ }
+ }
+
+ pfm_stats[this_cpu].pfm_smpl_handler_calls++;
+
+ start_cycles = ia64_get_itc();
+
+ /*
+ * call custom buffer format record (handler) routine
+ */
+ ret = (*ctx->ctx_buf_fmt->fmt_handler)(task, ctx->ctx_smpl_hdr, ovfl_arg, regs, tstamp);
+
+ end_cycles = ia64_get_itc();
+
+ /*
+ * For those controls, we take the union because they have
+ * an all or nothing behavior.
+ */
+ ovfl_ctrl.bits.notify_user |= ovfl_arg->ovfl_ctrl.bits.notify_user;
+ ovfl_ctrl.bits.block_task |= ovfl_arg->ovfl_ctrl.bits.block_task;
+ ovfl_ctrl.bits.mask_monitoring |= ovfl_arg->ovfl_ctrl.bits.mask_monitoring;
+ /*
+ * build the bitmask of pmds to reset now
+ */
+ if (ovfl_arg->ovfl_ctrl.bits.reset_ovfl_pmds) reset_pmds |= mask;
+
+ pfm_stats[this_cpu].pfm_smpl_handler_cycles += end_cycles - start_cycles;
+ }
+ /*
+ * when the module cannot handle the rest of the overflows, we abort right here
+ */
+ if (ret && pmd_mask) {
+ DPRINT(("handler aborts leftover ovfl_pmds=0x%lx\n",
+ pmd_mask<<PMU_FIRST_COUNTER));
+ }
+ /*
+ * remove the pmds we reset now from the set of pmds to reset in pfm_restart()
+ */
+ ovfl_pmds &= ~reset_pmds;
+ } else {
+ /*
+ * when no sampling module is used, then the default
+ * is to notify on overflow if requested by user
+ */
+ ovfl_ctrl.bits.notify_user = ovfl_notify ? 1 : 0;
+ ovfl_ctrl.bits.block_task = ovfl_notify ? 1 : 0;
+ ovfl_ctrl.bits.mask_monitoring = ovfl_notify ? 1 : 0; /* XXX: change for saturation */
+ ovfl_ctrl.bits.reset_ovfl_pmds = ovfl_notify ? 0 : 1;
+ /*
+ * if needed, we reset all overflowed pmds
+ */
+ if (ovfl_notify == 0) reset_pmds = ovfl_pmds;
+ }
+
+ DPRINT_ovfl(("ovfl_pmds=0x%lx reset_pmds=0x%lx\n", ovfl_pmds, reset_pmds));
+
+ /*
+ * reset the requested PMD registers using the short reset values
+ */
+ if (reset_pmds) {
+ unsigned long bm = reset_pmds;
+ pfm_reset_regs(ctx, &bm, PFM_PMD_SHORT_RESET);
+ }
+
+ if (ovfl_notify && ovfl_ctrl.bits.notify_user) {
+ /*
+ * keep track of what to reset when unblocking
+ */
+ ctx->ctx_ovfl_regs[0] = ovfl_pmds;
+
+ /*
+ * check for blocking context
+ */
+ if (CTX_OVFL_NOBLOCK(ctx) == 0 && ovfl_ctrl.bits.block_task) {
+
+ ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_BLOCK;
+
+ /*
+ * set the perfmon specific checking pending work for the task
+ */
+ PFM_SET_WORK_PENDING(task, 1);
+
+ /*
+ * when coming from ctxsw, current still points to the
+ * previous task, therefore we must work with task and not current.
+ */
+ pfm_set_task_notify(task);
+ }
+ /*
+ * defer until state is changed (shorten spin window). the context is locked
+ * anyway, so the signal receiver would come spin for nothing.
+ */
+ must_notify = 1;
+ }
+
+ DPRINT_ovfl(("owner [%d] pending=%ld reason=%u ovfl_pmds=0x%lx ovfl_notify=0x%lx masked=%d\n",
+ GET_PMU_OWNER() ? GET_PMU_OWNER()->pid : -1,
+ PFM_GET_WORK_PENDING(task),
+ ctx->ctx_fl_trap_reason,
+ ovfl_pmds,
+ ovfl_notify,
+ ovfl_ctrl.bits.mask_monitoring ? 1 : 0));
+ /*
+ * in case monitoring must be stopped, we toggle the psr bits
+ */
+ if (ovfl_ctrl.bits.mask_monitoring) {
+ pfm_mask_monitoring(task);
+ ctx->ctx_state = PFM_CTX_MASKED;
+ ctx->ctx_fl_can_restart = 1;
+ }
+
+ /*
+ * send notification now
+ */
+ if (must_notify) pfm_ovfl_notify_user(ctx, ovfl_notify);
+
+ return;
+
+sanity_check:
+ printk(KERN_ERR "perfmon: CPU%d overflow handler [%d] pmc0=0x%lx\n",
+ smp_processor_id(),
+ task ? task->pid : -1,
+ pmc0);
+ return;
+
+stop_monitoring:
+ /*
+ * in SMP, zombie context is never restored but reclaimed in pfm_load_regs().
+ * Moreover, zombies are also reclaimed in pfm_save_regs(). Therefore we can
+ * come here as zombie only if the task is the current task. In which case, we
+ * can access the PMU hardware directly.
+ *
+ * Note that zombies do have PM_VALID set. So here we do the minimal.
+ *
+ * In case the context was zombified it could not be reclaimed at the time
+ * the monitoring program exited. At this point, the PMU reservation has been
+ * returned, the sampiing buffer has been freed. We must convert this call
+ * into a spurious interrupt. However, we must also avoid infinite overflows
+ * by stopping monitoring for this task. We can only come here for a per-task
+ * context. All we need to do is to stop monitoring using the psr bits which
+ * are always task private. By re-enabling secure montioring, we ensure that
+ * the monitored task will not be able to re-activate monitoring.
+ * The task will eventually be context switched out, at which point the context
+ * will be reclaimed (that includes releasing ownership of the PMU).
+ *
+ * So there might be a window of time where the number of per-task session is zero
+ * yet one PMU might have a owner and get at most one overflow interrupt for a zombie
+ * context. This is safe because if a per-task session comes in, it will push this one
+ * out and by the virtue on pfm_save_regs(), this one will disappear. If a system wide
+ * session is force on that CPU, given that we use task pinning, pfm_save_regs() will
+ * also push our zombie context out.
+ *
+ * Overall pretty hairy stuff....
+ */
+ DPRINT(("ctx is zombie for [%d], converted to spurious\n", task ? task->pid: -1));
+ pfm_clear_psr_up();
+ ia64_psr(regs)->up = 0;
+ ia64_psr(regs)->sp = 1;
+ return;
+}
+
+static int
+pfm_do_interrupt_handler(int irq, void *arg, struct pt_regs *regs)
+{
+ struct task_struct *task;
+ pfm_context_t *ctx;
+ unsigned long flags;
+ u64 pmc0;
+ int this_cpu = smp_processor_id();
+ int retval = 0;
+
+ pfm_stats[this_cpu].pfm_ovfl_intr_count++;
+
+ /*
+ * srlz.d done before arriving here
+ */
+ pmc0 = ia64_get_pmc(0);
+
+ task = GET_PMU_OWNER();
+ ctx = GET_PMU_CTX();
+
+ /*
+ * if we have some pending bits set
+ * assumes : if any PMC0.bit[63-1] is set, then PMC0.fr = 1
+ */
+ if (PMC0_HAS_OVFL(pmc0) && task) {
+ /*
+ * we assume that pmc0.fr is always set here
+ */
+
+ /* sanity check */
+ if (!ctx) goto report_spurious1;
+
+ if (ctx->ctx_fl_system == 0 && (task->thread.flags & IA64_THREAD_PM_VALID) == 0)
+ goto report_spurious2;
+
+ PROTECT_CTX_NOPRINT(ctx, flags);
+
+ pfm_overflow_handler(task, ctx, pmc0, regs);
+
+ UNPROTECT_CTX_NOPRINT(ctx, flags);
+
+ } else {
+ pfm_stats[this_cpu].pfm_spurious_ovfl_intr_count++;
+ retval = -1;
+ }
+ /*
+ * keep it unfrozen at all times
+ */
+ pfm_unfreeze_pmu();
+
+ return retval;
+
+report_spurious1:
+ printk(KERN_INFO "perfmon: spurious overflow interrupt on CPU%d: process %d has no PFM context\n",
+ this_cpu, task->pid);
+ pfm_unfreeze_pmu();
+ return -1;
+report_spurious2:
+ printk(KERN_INFO "perfmon: spurious overflow interrupt on CPU%d: process %d, invalid flag\n",
+ this_cpu,
+ task->pid);
+ pfm_unfreeze_pmu();
+ return -1;
+}
+
+static irqreturn_t
+pfm_interrupt_handler(int irq, void *arg, struct pt_regs *regs)
+{
+ unsigned long start_cycles, total_cycles;
+ unsigned long min, max;
+ int this_cpu;
+ int ret;
+
+ this_cpu = get_cpu();
+ min = pfm_stats[this_cpu].pfm_ovfl_intr_cycles_min;
+ max = pfm_stats[this_cpu].pfm_ovfl_intr_cycles_max;
+
+ start_cycles = ia64_get_itc();
+
+ ret = pfm_do_interrupt_handler(irq, arg, regs);
+
+ total_cycles = ia64_get_itc();
+
+ /*
+ * don't measure spurious interrupts
+ */
+ if (likely(ret == 0)) {
+ total_cycles -= start_cycles;
+
+ if (total_cycles < min) pfm_stats[this_cpu].pfm_ovfl_intr_cycles_min = total_cycles;
+ if (total_cycles > max) pfm_stats[this_cpu].pfm_ovfl_intr_cycles_max = total_cycles;
+
+ pfm_stats[this_cpu].pfm_ovfl_intr_cycles += total_cycles;
+ }
+ put_cpu_no_resched();
+ return IRQ_HANDLED;
+}
+
+/*
+ * /proc/perfmon interface, for debug only
+ */
+
+#define PFM_PROC_SHOW_HEADER ((void *)NR_CPUS+1)
+
+static void *
+pfm_proc_start(struct seq_file *m, loff_t *pos)
+{
+ if (*pos == 0) {
+ return PFM_PROC_SHOW_HEADER;
+ }
+
+ while (*pos <= NR_CPUS) {
+ if (cpu_online(*pos - 1)) {
+ return (void *)*pos;
+ }
+ ++*pos;
+ }
+ return NULL;
+}
+
+static void *
+pfm_proc_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ ++*pos;
+ return pfm_proc_start(m, pos);
+}
+
+static void
+pfm_proc_stop(struct seq_file *m, void *v)
+{
+}
+
+static void
+pfm_proc_show_header(struct seq_file *m)
+{
+ struct list_head * pos;
+ pfm_buffer_fmt_t * entry;
+ unsigned long flags;
+
+ seq_printf(m,
+ "perfmon version : %u.%u\n"
+ "model : %s\n"
+ "fastctxsw : %s\n"
+ "expert mode : %s\n"
+ "ovfl_mask : 0x%lx\n"
+ "PMU flags : 0x%x\n",
+ PFM_VERSION_MAJ, PFM_VERSION_MIN,
+ pmu_conf->pmu_name,
+ pfm_sysctl.fastctxsw > 0 ? "Yes": "No",
+ pfm_sysctl.expert_mode > 0 ? "Yes": "No",
+ pmu_conf->ovfl_val,
+ pmu_conf->flags);
+
+ LOCK_PFS(flags);
+
+ seq_printf(m,
+ "proc_sessions : %u\n"
+ "sys_sessions : %u\n"
+ "sys_use_dbregs : %u\n"
+ "ptrace_use_dbregs : %u\n",
+ pfm_sessions.pfs_task_sessions,
+ pfm_sessions.pfs_sys_sessions,
+ pfm_sessions.pfs_sys_use_dbregs,
+ pfm_sessions.pfs_ptrace_use_dbregs);
+
+ UNLOCK_PFS(flags);
+
+ spin_lock(&pfm_buffer_fmt_lock);
+
+ list_for_each(pos, &pfm_buffer_fmt_list) {
+ entry = list_entry(pos, pfm_buffer_fmt_t, fmt_list);
+ seq_printf(m, "format : %02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x %s\n",
+ entry->fmt_uuid[0],
+ entry->fmt_uuid[1],
+ entry->fmt_uuid[2],
+ entry->fmt_uuid[3],
+ entry->fmt_uuid[4],
+ entry->fmt_uuid[5],
+ entry->fmt_uuid[6],
+ entry->fmt_uuid[7],
+ entry->fmt_uuid[8],
+ entry->fmt_uuid[9],
+ entry->fmt_uuid[10],
+ entry->fmt_uuid[11],
+ entry->fmt_uuid[12],
+ entry->fmt_uuid[13],
+ entry->fmt_uuid[14],
+ entry->fmt_uuid[15],
+ entry->fmt_name);
+ }
+ spin_unlock(&pfm_buffer_fmt_lock);
+
+}
+
+static int
+pfm_proc_show(struct seq_file *m, void *v)
+{
+ unsigned long psr;
+ unsigned int i;
+ int cpu;
+
+ if (v == PFM_PROC_SHOW_HEADER) {
+ pfm_proc_show_header(m);
+ return 0;
+ }
+
+ /* show info for CPU (v - 1) */
+
+ cpu = (long)v - 1;
+ seq_printf(m,
+ "CPU%-2d overflow intrs : %lu\n"
+ "CPU%-2d overflow cycles : %lu\n"
+ "CPU%-2d overflow min : %lu\n"
+ "CPU%-2d overflow max : %lu\n"
+ "CPU%-2d smpl handler calls : %lu\n"
+ "CPU%-2d smpl handler cycles : %lu\n"
+ "CPU%-2d spurious intrs : %lu\n"
+ "CPU%-2d replay intrs : %lu\n"
+ "CPU%-2d syst_wide : %d\n"
+ "CPU%-2d dcr_pp : %d\n"
+ "CPU%-2d exclude idle : %d\n"
+ "CPU%-2d owner : %d\n"
+ "CPU%-2d context : %p\n"
+ "CPU%-2d activations : %lu\n",
+ cpu, pfm_stats[cpu].pfm_ovfl_intr_count,
+ cpu, pfm_stats[cpu].pfm_ovfl_intr_cycles,
+ cpu, pfm_stats[cpu].pfm_ovfl_intr_cycles_min,
+ cpu, pfm_stats[cpu].pfm_ovfl_intr_cycles_max,
+ cpu, pfm_stats[cpu].pfm_smpl_handler_calls,
+ cpu, pfm_stats[cpu].pfm_smpl_handler_cycles,
+ cpu, pfm_stats[cpu].pfm_spurious_ovfl_intr_count,
+ cpu, pfm_stats[cpu].pfm_replay_ovfl_intr_count,
+ cpu, pfm_get_cpu_data(pfm_syst_info, cpu) & PFM_CPUINFO_SYST_WIDE ? 1 : 0,
+ cpu, pfm_get_cpu_data(pfm_syst_info, cpu) & PFM_CPUINFO_DCR_PP ? 1 : 0,
+ cpu, pfm_get_cpu_data(pfm_syst_info, cpu) & PFM_CPUINFO_EXCL_IDLE ? 1 : 0,
+ cpu, pfm_get_cpu_data(pmu_owner, cpu) ? pfm_get_cpu_data(pmu_owner, cpu)->pid: -1,
+ cpu, pfm_get_cpu_data(pmu_ctx, cpu),
+ cpu, pfm_get_cpu_data(pmu_activation_number, cpu));
+
+ if (num_online_cpus() == 1 && pfm_sysctl.debug > 0) {
+
+ psr = pfm_get_psr();
+
+ ia64_srlz_d();
+
+ seq_printf(m,
+ "CPU%-2d psr : 0x%lx\n"
+ "CPU%-2d pmc0 : 0x%lx\n",
+ cpu, psr,
+ cpu, ia64_get_pmc(0));
+
+ for (i=0; PMC_IS_LAST(i) == 0; i++) {
+ if (PMC_IS_COUNTING(i) == 0) continue;
+ seq_printf(m,
+ "CPU%-2d pmc%u : 0x%lx\n"
+ "CPU%-2d pmd%u : 0x%lx\n",
+ cpu, i, ia64_get_pmc(i),
+ cpu, i, ia64_get_pmd(i));
+ }
+ }
+ return 0;
+}
+
+struct seq_operations pfm_seq_ops = {
+ .start = pfm_proc_start,
+ .next = pfm_proc_next,
+ .stop = pfm_proc_stop,
+ .show = pfm_proc_show
+};
+
+static int
+pfm_proc_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &pfm_seq_ops);
+}
+
+
+/*
+ * we come here as soon as local_cpu_data->pfm_syst_wide is set. this happens
+ * during pfm_enable() hence before pfm_start(). We cannot assume monitoring
+ * is active or inactive based on mode. We must rely on the value in
+ * local_cpu_data->pfm_syst_info
+ */
+void
+pfm_syst_wide_update_task(struct task_struct *task, unsigned long info, int is_ctxswin)
+{
+ struct pt_regs *regs;
+ unsigned long dcr;
+ unsigned long dcr_pp;
+
+ dcr_pp = info & PFM_CPUINFO_DCR_PP ? 1 : 0;
+
+ /*
+ * pid 0 is guaranteed to be the idle task. There is one such task with pid 0
+ * on every CPU, so we can rely on the pid to identify the idle task.
+ */
+ if ((info & PFM_CPUINFO_EXCL_IDLE) == 0 || task->pid) {
+ regs = ia64_task_regs(task);
+ ia64_psr(regs)->pp = is_ctxswin ? dcr_pp : 0;
+ return;
+ }
+ /*
+ * if monitoring has started
+ */
+ if (dcr_pp) {
+ dcr = ia64_getreg(_IA64_REG_CR_DCR);
+ /*
+ * context switching in?
+ */
+ if (is_ctxswin) {
+ /* mask monitoring for the idle task */
+ ia64_setreg(_IA64_REG_CR_DCR, dcr & ~IA64_DCR_PP);
+ pfm_clear_psr_pp();
+ ia64_srlz_i();
+ return;
+ }
+ /*
+ * context switching out
+ * restore monitoring for next task
+ *
+ * Due to inlining this odd if-then-else construction generates
+ * better code.
+ */
+ ia64_setreg(_IA64_REG_CR_DCR, dcr |IA64_DCR_PP);
+ pfm_set_psr_pp();
+ ia64_srlz_i();
+ }
+}
+
+#ifdef CONFIG_SMP
+
+static void
+pfm_force_cleanup(pfm_context_t *ctx, struct pt_regs *regs)
+{
+ struct task_struct *task = ctx->ctx_task;
+
+ ia64_psr(regs)->up = 0;
+ ia64_psr(regs)->sp = 1;
+
+ if (GET_PMU_OWNER() == task) {
+ DPRINT(("cleared ownership for [%d]\n", ctx->ctx_task->pid));
+ SET_PMU_OWNER(NULL, NULL);
+ }
+
+ /*
+ * disconnect the task from the context and vice-versa
+ */
+ PFM_SET_WORK_PENDING(task, 0);
+
+ task->thread.pfm_context = NULL;
+ task->thread.flags &= ~IA64_THREAD_PM_VALID;
+
+ DPRINT(("force cleanup for [%d]\n", task->pid));
+}
+
+
+/*
+ * in 2.6, interrupts are masked when we come here and the runqueue lock is held
+ */
+void
+pfm_save_regs(struct task_struct *task)
+{
+ pfm_context_t *ctx;
+ struct thread_struct *t;
+ unsigned long flags;
+ u64 psr;
+
+
+ ctx = PFM_GET_CTX(task);
+ if (ctx == NULL) return;
+ t = &task->thread;
+
+ /*
+ * we always come here with interrupts ALREADY disabled by
+ * the scheduler. So we simply need to protect against concurrent
+ * access, not CPU concurrency.
+ */
+ flags = pfm_protect_ctx_ctxsw(ctx);
+
+ if (ctx->ctx_state == PFM_CTX_ZOMBIE) {
+ struct pt_regs *regs = ia64_task_regs(task);
+
+ pfm_clear_psr_up();
+
+ pfm_force_cleanup(ctx, regs);
+
+ BUG_ON(ctx->ctx_smpl_hdr);
+
+ pfm_unprotect_ctx_ctxsw(ctx, flags);
+
+ pfm_context_free(ctx);
+ return;
+ }
+
+ /*
+ * save current PSR: needed because we modify it
+ */
+ ia64_srlz_d();
+ psr = pfm_get_psr();
+
+ BUG_ON(psr & (IA64_PSR_I));
+
+ /*
+ * stop monitoring:
+ * This is the last instruction which may generate an overflow
+ *
+ * We do not need to set psr.sp because, it is irrelevant in kernel.
+ * It will be restored from ipsr when going back to user level
+ */
+ pfm_clear_psr_up();
+
+ /*
+ * keep a copy of psr.up (for reload)
+ */
+ ctx->ctx_saved_psr_up = psr & IA64_PSR_UP;
+
+ /*
+ * release ownership of this PMU.
+ * PM interrupts are masked, so nothing
+ * can happen.
+ */
+ SET_PMU_OWNER(NULL, NULL);
+
+ /*
+ * we systematically save the PMD as we have no
+ * guarantee we will be schedule at that same
+ * CPU again.
+ */
+ pfm_save_pmds(t->pmds, ctx->ctx_used_pmds[0]);
+
+ /*
+ * save pmc0 ia64_srlz_d() done in pfm_save_pmds()
+ * we will need it on the restore path to check
+ * for pending overflow.
+ */
+ t->pmcs[0] = ia64_get_pmc(0);
+
+ /*
+ * unfreeze PMU if had pending overflows
+ */
+ if (t->pmcs[0] & ~0x1UL) pfm_unfreeze_pmu();
+
+ /*
+ * finally, allow context access.
+ * interrupts will still be masked after this call.
+ */
+ pfm_unprotect_ctx_ctxsw(ctx, flags);
+}
+
+#else /* !CONFIG_SMP */
+void
+pfm_save_regs(struct task_struct *task)
+{
+ pfm_context_t *ctx;
+ u64 psr;
+
+ ctx = PFM_GET_CTX(task);
+ if (ctx == NULL) return;
+
+ /*
+ * save current PSR: needed because we modify it
+ */
+ psr = pfm_get_psr();
+
+ BUG_ON(psr & (IA64_PSR_I));
+
+ /*
+ * stop monitoring:
+ * This is the last instruction which may generate an overflow
+ *
+ * We do not need to set psr.sp because, it is irrelevant in kernel.
+ * It will be restored from ipsr when going back to user level
+ */
+ pfm_clear_psr_up();
+
+ /*
+ * keep a copy of psr.up (for reload)
+ */
+ ctx->ctx_saved_psr_up = psr & IA64_PSR_UP;
+}
+
+static void
+pfm_lazy_save_regs (struct task_struct *task)
+{
+ pfm_context_t *ctx;
+ struct thread_struct *t;
+ unsigned long flags;
+
+ { u64 psr = pfm_get_psr();
+ BUG_ON(psr & IA64_PSR_UP);
+ }
+
+ ctx = PFM_GET_CTX(task);
+ t = &task->thread;
+
+ /*
+ * we need to mask PMU overflow here to
+ * make sure that we maintain pmc0 until
+ * we save it. overflow interrupts are
+ * treated as spurious if there is no
+ * owner.
+ *
+ * XXX: I don't think this is necessary
+ */
+ PROTECT_CTX(ctx,flags);
+
+ /*
+ * release ownership of this PMU.
+ * must be done before we save the registers.
+ *
+ * after this call any PMU interrupt is treated
+ * as spurious.
+ */
+ SET_PMU_OWNER(NULL, NULL);
+
+ /*
+ * save all the pmds we use
+ */
+ pfm_save_pmds(t->pmds, ctx->ctx_used_pmds[0]);
+
+ /*
+ * save pmc0 ia64_srlz_d() done in pfm_save_pmds()
+ * it is needed to check for pended overflow
+ * on the restore path
+ */
+ t->pmcs[0] = ia64_get_pmc(0);
+
+ /*
+ * unfreeze PMU if had pending overflows
+ */
+ if (t->pmcs[0] & ~0x1UL) pfm_unfreeze_pmu();
+
+ /*
+ * now get can unmask PMU interrupts, they will
+ * be treated as purely spurious and we will not
+ * lose any information
+ */
+ UNPROTECT_CTX(ctx,flags);
+}
+#endif /* CONFIG_SMP */
+
+#ifdef CONFIG_SMP
+/*
+ * in 2.6, interrupts are masked when we come here and the runqueue lock is held
+ */
+void
+pfm_load_regs (struct task_struct *task)
+{
+ pfm_context_t *ctx;
+ struct thread_struct *t;
+ unsigned long pmc_mask = 0UL, pmd_mask = 0UL;
+ unsigned long flags;
+ u64 psr, psr_up;
+ int need_irq_resend;
+
+ ctx = PFM_GET_CTX(task);
+ if (unlikely(ctx == NULL)) return;
+
+ BUG_ON(GET_PMU_OWNER());
+
+ t = &task->thread;
+ /*
+ * possible on unload
+ */
+ if (unlikely((t->flags & IA64_THREAD_PM_VALID) == 0)) return;
+
+ /*
+ * we always come here with interrupts ALREADY disabled by
+ * the scheduler. So we simply need to protect against concurrent
+ * access, not CPU concurrency.
+ */
+ flags = pfm_protect_ctx_ctxsw(ctx);
+ psr = pfm_get_psr();
+
+ need_irq_resend = pmu_conf->flags & PFM_PMU_IRQ_RESEND;
+
+ BUG_ON(psr & (IA64_PSR_UP|IA64_PSR_PP));
+ BUG_ON(psr & IA64_PSR_I);
+
+ if (unlikely(ctx->ctx_state == PFM_CTX_ZOMBIE)) {
+ struct pt_regs *regs = ia64_task_regs(task);
+
+ BUG_ON(ctx->ctx_smpl_hdr);
+
+ pfm_force_cleanup(ctx, regs);
+
+ pfm_unprotect_ctx_ctxsw(ctx, flags);
+
+ /*
+ * this one (kmalloc'ed) is fine with interrupts disabled
+ */
+ pfm_context_free(ctx);
+
+ return;
+ }
+
+ /*
+ * we restore ALL the debug registers to avoid picking up
+ * stale state.
+ */
+ if (ctx->ctx_fl_using_dbreg) {
+ pfm_restore_ibrs(ctx->ctx_ibrs, pmu_conf->num_ibrs);
+ pfm_restore_dbrs(ctx->ctx_dbrs, pmu_conf->num_dbrs);
+ }
+ /*
+ * retrieve saved psr.up
+ */
+ psr_up = ctx->ctx_saved_psr_up;
+
+ /*
+ * if we were the last user of the PMU on that CPU,
+ * then nothing to do except restore psr
+ */
+ if (GET_LAST_CPU(ctx) == smp_processor_id() && ctx->ctx_last_activation == GET_ACTIVATION()) {
+
+ /*
+ * retrieve partial reload masks (due to user modifications)
+ */
+ pmc_mask = ctx->ctx_reload_pmcs[0];
+ pmd_mask = ctx->ctx_reload_pmds[0];
+
+ } else {
+ /*
+ * To avoid leaking information to the user level when psr.sp=0,
+ * we must reload ALL implemented pmds (even the ones we don't use).
+ * In the kernel we only allow PFM_READ_PMDS on registers which
+ * we initialized or requested (sampling) so there is no risk there.
+ */
+ pmd_mask = pfm_sysctl.fastctxsw ? ctx->ctx_used_pmds[0] : ctx->ctx_all_pmds[0];
+
+ /*
+ * ALL accessible PMCs are systematically reloaded, unused registers
+ * get their default (from pfm_reset_pmu_state()) values to avoid picking
+ * up stale configuration.
+ *
+ * PMC0 is never in the mask. It is always restored separately.
+ */
+ pmc_mask = ctx->ctx_all_pmcs[0];
+ }
+ /*
+ * when context is MASKED, we will restore PMC with plm=0
+ * and PMD with stale information, but that's ok, nothing
+ * will be captured.
+ *
+ * XXX: optimize here
+ */
+ if (pmd_mask) pfm_restore_pmds(t->pmds, pmd_mask);
+ if (pmc_mask) pfm_restore_pmcs(t->pmcs, pmc_mask);
+
+ /*
+ * check for pending overflow at the time the state
+ * was saved.
+ */
+ if (unlikely(PMC0_HAS_OVFL(t->pmcs[0]))) {
+ /*
+ * reload pmc0 with the overflow information
+ * On McKinley PMU, this will trigger a PMU interrupt
+ */
+ ia64_set_pmc(0, t->pmcs[0]);
+ ia64_srlz_d();
+ t->pmcs[0] = 0UL;
+
+ /*
+ * will replay the PMU interrupt
+ */
+ if (need_irq_resend) hw_resend_irq(NULL, IA64_PERFMON_VECTOR);
+
+ pfm_stats[smp_processor_id()].pfm_replay_ovfl_intr_count++;
+ }
+
+ /*
+ * we just did a reload, so we reset the partial reload fields
+ */
+ ctx->ctx_reload_pmcs[0] = 0UL;
+ ctx->ctx_reload_pmds[0] = 0UL;
+
+ SET_LAST_CPU(ctx, smp_processor_id());
+
+ /*
+ * dump activation value for this PMU
+ */
+ INC_ACTIVATION();
+ /*
+ * record current activation for this context
+ */
+ SET_ACTIVATION(ctx);
+
+ /*
+ * establish new ownership.
+ */
+ SET_PMU_OWNER(task, ctx);
+
+ /*
+ * restore the psr.up bit. measurement
+ * is active again.
+ * no PMU interrupt can happen at this point
+ * because we still have interrupts disabled.
+ */
+ if (likely(psr_up)) pfm_set_psr_up();
+
+ /*
+ * allow concurrent access to context
+ */
+ pfm_unprotect_ctx_ctxsw(ctx, flags);
+}
+#else /* !CONFIG_SMP */
+/*
+ * reload PMU state for UP kernels
+ * in 2.5 we come here with interrupts disabled
+ */
+void
+pfm_load_regs (struct task_struct *task)
+{
+ struct thread_struct *t;
+ pfm_context_t *ctx;
+ struct task_struct *owner;
+ unsigned long pmd_mask, pmc_mask;
+ u64 psr, psr_up;
+ int need_irq_resend;
+
+ owner = GET_PMU_OWNER();
+ ctx = PFM_GET_CTX(task);
+ t = &task->thread;
+ psr = pfm_get_psr();
+
+ BUG_ON(psr & (IA64_PSR_UP|IA64_PSR_PP));
+ BUG_ON(psr & IA64_PSR_I);
+
+ /*
+ * we restore ALL the debug registers to avoid picking up
+ * stale state.
+ *
+ * This must be done even when the task is still the owner
+ * as the registers may have been modified via ptrace()
+ * (not perfmon) by the previous task.
+ */
+ if (ctx->ctx_fl_using_dbreg) {
+ pfm_restore_ibrs(ctx->ctx_ibrs, pmu_conf->num_ibrs);
+ pfm_restore_dbrs(ctx->ctx_dbrs, pmu_conf->num_dbrs);
+ }
+
+ /*
+ * retrieved saved psr.up
+ */
+ psr_up = ctx->ctx_saved_psr_up;
+ need_irq_resend = pmu_conf->flags & PFM_PMU_IRQ_RESEND;
+
+ /*
+ * short path, our state is still there, just
+ * need to restore psr and we go
+ *
+ * we do not touch either PMC nor PMD. the psr is not touched
+ * by the overflow_handler. So we are safe w.r.t. to interrupt
+ * concurrency even without interrupt masking.
+ */
+ if (likely(owner == task)) {
+ if (likely(psr_up)) pfm_set_psr_up();
+ return;
+ }
+
+ /*
+ * someone else is still using the PMU, first push it out and
+ * then we'll be able to install our stuff !
+ *
+ * Upon return, there will be no owner for the current PMU
+ */
+ if (owner) pfm_lazy_save_regs(owner);
+
+ /*
+ * To avoid leaking information to the user level when psr.sp=0,
+ * we must reload ALL implemented pmds (even the ones we don't use).
+ * In the kernel we only allow PFM_READ_PMDS on registers which
+ * we initialized or requested (sampling) so there is no risk there.
+ */
+ pmd_mask = pfm_sysctl.fastctxsw ? ctx->ctx_used_pmds[0] : ctx->ctx_all_pmds[0];
+
+ /*
+ * ALL accessible PMCs are systematically reloaded, unused registers
+ * get their default (from pfm_reset_pmu_state()) values to avoid picking
+ * up stale configuration.
+ *
+ * PMC0 is never in the mask. It is always restored separately
+ */
+ pmc_mask = ctx->ctx_all_pmcs[0];
+
+ pfm_restore_pmds(t->pmds, pmd_mask);
+ pfm_restore_pmcs(t->pmcs, pmc_mask);
+
+ /*
+ * check for pending overflow at the time the state
+ * was saved.
+ */
+ if (unlikely(PMC0_HAS_OVFL(t->pmcs[0]))) {
+ /*
+ * reload pmc0 with the overflow information
+ * On McKinley PMU, this will trigger a PMU interrupt
+ */
+ ia64_set_pmc(0, t->pmcs[0]);
+ ia64_srlz_d();
+
+ t->pmcs[0] = 0UL;
+
+ /*
+ * will replay the PMU interrupt
+ */
+ if (need_irq_resend) hw_resend_irq(NULL, IA64_PERFMON_VECTOR);
+
+ pfm_stats[smp_processor_id()].pfm_replay_ovfl_intr_count++;
+ }
+
+ /*
+ * establish new ownership.
+ */
+ SET_PMU_OWNER(task, ctx);
+
+ /*
+ * restore the psr.up bit. measurement
+ * is active again.
+ * no PMU interrupt can happen at this point
+ * because we still have interrupts disabled.
+ */
+ if (likely(psr_up)) pfm_set_psr_up();
+}
+#endif /* CONFIG_SMP */
+
+/*
+ * this function assumes monitoring is stopped
+ */
+static void
+pfm_flush_pmds(struct task_struct *task, pfm_context_t *ctx)
+{
+ u64 pmc0;
+ unsigned long mask2, val, pmd_val, ovfl_val;
+ int i, can_access_pmu = 0;
+ int is_self;
+
+ /*
+ * is the caller the task being monitored (or which initiated the
+ * session for system wide measurements)
+ */
+ is_self = ctx->ctx_task == task ? 1 : 0;
+
+ /*
+ * can access PMU is task is the owner of the PMU state on the current CPU
+ * or if we are running on the CPU bound to the context in system-wide mode
+ * (that is not necessarily the task the context is attached to in this mode).
+ * In system-wide we always have can_access_pmu true because a task running on an
+ * invalid processor is flagged earlier in the call stack (see pfm_stop).
+ */
+ can_access_pmu = (GET_PMU_OWNER() == task) || (ctx->ctx_fl_system && ctx->ctx_cpu == smp_processor_id());
+ if (can_access_pmu) {
+ /*
+ * Mark the PMU as not owned
+ * This will cause the interrupt handler to do nothing in case an overflow
+ * interrupt was in-flight
+ * This also guarantees that pmc0 will contain the final state
+ * It virtually gives us full control on overflow processing from that point
+ * on.
+ */
+ SET_PMU_OWNER(NULL, NULL);
+ DPRINT(("releasing ownership\n"));
+
+ /*
+ * read current overflow status:
+ *
+ * we are guaranteed to read the final stable state
+ */
+ ia64_srlz_d();
+ pmc0 = ia64_get_pmc(0); /* slow */
+
+ /*
+ * reset freeze bit, overflow status information destroyed
+ */
+ pfm_unfreeze_pmu();
+ } else {
+ pmc0 = task->thread.pmcs[0];
+ /*
+ * clear whatever overflow status bits there were
+ */
+ task->thread.pmcs[0] = 0;
+ }
+ ovfl_val = pmu_conf->ovfl_val;
+ /*
+ * we save all the used pmds
+ * we take care of overflows for counting PMDs
+ *
+ * XXX: sampling situation is not taken into account here
+ */
+ mask2 = ctx->ctx_used_pmds[0];
+
+ DPRINT(("is_self=%d ovfl_val=0x%lx mask2=0x%lx\n", is_self, ovfl_val, mask2));
+
+ for (i = 0; mask2; i++, mask2>>=1) {
+
+ /* skip non used pmds */
+ if ((mask2 & 0x1) == 0) continue;
+
+ /*
+ * can access PMU always true in system wide mode
+ */
+ val = pmd_val = can_access_pmu ? ia64_get_pmd(i) : task->thread.pmds[i];
+
+ if (PMD_IS_COUNTING(i)) {
+ DPRINT(("[%d] pmd[%d] ctx_pmd=0x%lx hw_pmd=0x%lx\n",
+ task->pid,
+ i,
+ ctx->ctx_pmds[i].val,
+ val & ovfl_val));
+
+ /*
+ * we rebuild the full 64 bit value of the counter
+ */
+ val = ctx->ctx_pmds[i].val + (val & ovfl_val);
+
+ /*
+ * now everything is in ctx_pmds[] and we need
+ * to clear the saved context from save_regs() such that
+ * pfm_read_pmds() gets the correct value
+ */
+ pmd_val = 0UL;
+
+ /*
+ * take care of overflow inline
+ */
+ if (pmc0 & (1UL << i)) {
+ val += 1 + ovfl_val;
+ DPRINT(("[%d] pmd[%d] overflowed\n", task->pid, i));
+ }
+ }
+
+ DPRINT(("[%d] ctx_pmd[%d]=0x%lx pmd_val=0x%lx\n", task->pid, i, val, pmd_val));
+
+ if (is_self) task->thread.pmds[i] = pmd_val;
+
+ ctx->ctx_pmds[i].val = val;
+ }
+}
+
+static struct irqaction perfmon_irqaction = {
+ .handler = pfm_interrupt_handler,
+ .flags = SA_INTERRUPT,
+ .name = "perfmon"
+};
+
+/*
+ * perfmon initialization routine, called from the initcall() table
+ */
+static int init_pfm_fs(void);
+
+static int __init
+pfm_probe_pmu(void)
+{
+ pmu_config_t **p;
+ int family;
+
+ family = local_cpu_data->family;
+ p = pmu_confs;
+
+ while(*p) {
+ if ((*p)->probe) {
+ if ((*p)->probe() == 0) goto found;
+ } else if ((*p)->pmu_family == family || (*p)->pmu_family == 0xff) {
+ goto found;
+ }
+ p++;
+ }
+ return -1;
+found:
+ pmu_conf = *p;
+ return 0;
+}
+
+static struct file_operations pfm_proc_fops = {
+ .open = pfm_proc_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+int __init
+pfm_init(void)
+{
+ unsigned int n, n_counters, i;
+
+ printk("perfmon: version %u.%u IRQ %u\n",
+ PFM_VERSION_MAJ,
+ PFM_VERSION_MIN,
+ IA64_PERFMON_VECTOR);
+
+ if (pfm_probe_pmu()) {
+ printk(KERN_INFO "perfmon: disabled, there is no support for processor family %d\n",
+ local_cpu_data->family);
+ return -ENODEV;
+ }
+
+ /*
+ * compute the number of implemented PMD/PMC from the
+ * description tables
+ */
+ n = 0;
+ for (i=0; PMC_IS_LAST(i) == 0; i++) {
+ if (PMC_IS_IMPL(i) == 0) continue;
+ pmu_conf->impl_pmcs[i>>6] |= 1UL << (i&63);
+ n++;
+ }
+ pmu_conf->num_pmcs = n;
+
+ n = 0; n_counters = 0;
+ for (i=0; PMD_IS_LAST(i) == 0; i++) {
+ if (PMD_IS_IMPL(i) == 0) continue;
+ pmu_conf->impl_pmds[i>>6] |= 1UL << (i&63);
+ n++;
+ if (PMD_IS_COUNTING(i)) n_counters++;
+ }
+ pmu_conf->num_pmds = n;
+ pmu_conf->num_counters = n_counters;
+
+ /*
+ * sanity checks on the number of debug registers
+ */
+ if (pmu_conf->use_rr_dbregs) {
+ if (pmu_conf->num_ibrs > IA64_NUM_DBG_REGS) {
+ printk(KERN_INFO "perfmon: unsupported number of code debug registers (%u)\n", pmu_conf->num_ibrs);
+ pmu_conf = NULL;
+ return -1;
+ }
+ if (pmu_conf->num_dbrs > IA64_NUM_DBG_REGS) {
+ printk(KERN_INFO "perfmon: unsupported number of data debug registers (%u)\n", pmu_conf->num_ibrs);
+ pmu_conf = NULL;
+ return -1;
+ }
+ }
+
+ printk("perfmon: %s PMU detected, %u PMCs, %u PMDs, %u counters (%lu bits)\n",
+ pmu_conf->pmu_name,
+ pmu_conf->num_pmcs,
+ pmu_conf->num_pmds,
+ pmu_conf->num_counters,
+ ffz(pmu_conf->ovfl_val));
+
+ /* sanity check */
+ if (pmu_conf->num_pmds >= IA64_NUM_PMD_REGS || pmu_conf->num_pmcs >= IA64_NUM_PMC_REGS) {
+ printk(KERN_ERR "perfmon: not enough pmc/pmd, perfmon disabled\n");
+ pmu_conf = NULL;
+ return -1;
+ }
+
+ /*
+ * create /proc/perfmon (mostly for debugging purposes)
+ */
+ perfmon_dir = create_proc_entry("perfmon", S_IRUGO, NULL);
+ if (perfmon_dir == NULL) {
+ printk(KERN_ERR "perfmon: cannot create /proc entry, perfmon disabled\n");
+ pmu_conf = NULL;
+ return -1;
+ }
+ /*
+ * install customized file operations for /proc/perfmon entry
+ */
+ perfmon_dir->proc_fops = &pfm_proc_fops;
+
+ /*
+ * create /proc/sys/kernel/perfmon (for debugging purposes)
+ */
+ pfm_sysctl_header = register_sysctl_table(pfm_sysctl_root, 0);
+
+ /*
+ * initialize all our spinlocks
+ */
+ spin_lock_init(&pfm_sessions.pfs_lock);
+ spin_lock_init(&pfm_buffer_fmt_lock);
+
+ init_pfm_fs();
+
+ for(i=0; i < NR_CPUS; i++) pfm_stats[i].pfm_ovfl_intr_cycles_min = ~0UL;
+
+ return 0;
+}
+
+__initcall(pfm_init);
+
+/*
+ * this function is called before pfm_init()
+ */
+void
+pfm_init_percpu (void)
+{
+ /*
+ * make sure no measurement is active
+ * (may inherit programmed PMCs from EFI).
+ */
+ pfm_clear_psr_pp();
+ pfm_clear_psr_up();
+
+ /*
+ * we run with the PMU not frozen at all times
+ */
+ pfm_unfreeze_pmu();
+
+ if (smp_processor_id() == 0)
+ register_percpu_irq(IA64_PERFMON_VECTOR, &perfmon_irqaction);
+
+ ia64_setreg(_IA64_REG_CR_PMV, IA64_PERFMON_VECTOR);
+ ia64_srlz_d();
+}
+
+/*
+ * used for debug purposes only
+ */
+void
+dump_pmu_state(const char *from)
+{
+ struct task_struct *task;
+ struct thread_struct *t;
+ struct pt_regs *regs;
+ pfm_context_t *ctx;
+ unsigned long psr, dcr, info, flags;
+ int i, this_cpu;
+
+ local_irq_save(flags);
+
+ this_cpu = smp_processor_id();
+ regs = ia64_task_regs(current);
+ info = PFM_CPUINFO_GET();
+ dcr = ia64_getreg(_IA64_REG_CR_DCR);
+
+ if (info == 0 && ia64_psr(regs)->pp == 0 && (dcr & IA64_DCR_PP) == 0) {
+ local_irq_restore(flags);
+ return;
+ }
+
+ printk("CPU%d from %s() current [%d] iip=0x%lx %s\n",
+ this_cpu,
+ from,
+ current->pid,
+ regs->cr_iip,
+ current->comm);
+
+ task = GET_PMU_OWNER();
+ ctx = GET_PMU_CTX();
+
+ printk("->CPU%d owner [%d] ctx=%p\n", this_cpu, task ? task->pid : -1, ctx);
+
+ psr = pfm_get_psr();
+
+ printk("->CPU%d pmc0=0x%lx psr.pp=%d psr.up=%d dcr.pp=%d syst_info=0x%lx user_psr.up=%d user_psr.pp=%d\n",
+ this_cpu,
+ ia64_get_pmc(0),
+ psr & IA64_PSR_PP ? 1 : 0,
+ psr & IA64_PSR_UP ? 1 : 0,
+ dcr & IA64_DCR_PP ? 1 : 0,
+ info,
+ ia64_psr(regs)->up,
+ ia64_psr(regs)->pp);
+
+ ia64_psr(regs)->up = 0;
+ ia64_psr(regs)->pp = 0;
+
+ t = ¤t->thread;
+
+ for (i=1; PMC_IS_LAST(i) == 0; i++) {
+ if (PMC_IS_IMPL(i) == 0) continue;
+ printk("->CPU%d pmc[%d]=0x%lx thread_pmc[%d]=0x%lx\n", this_cpu, i, ia64_get_pmc(i), i, t->pmcs[i]);
+ }
+
+ for (i=1; PMD_IS_LAST(i) == 0; i++) {
+ if (PMD_IS_IMPL(i) == 0) continue;
+ printk("->CPU%d pmd[%d]=0x%lx thread_pmd[%d]=0x%lx\n", this_cpu, i, ia64_get_pmd(i), i, t->pmds[i]);
+ }
+
+ if (ctx) {
+ printk("->CPU%d ctx_state=%d vaddr=%p addr=%p fd=%d ctx_task=[%d] saved_psr_up=0x%lx\n",
+ this_cpu,
+ ctx->ctx_state,
+ ctx->ctx_smpl_vaddr,
+ ctx->ctx_smpl_hdr,
+ ctx->ctx_msgq_head,
+ ctx->ctx_msgq_tail,
+ ctx->ctx_saved_psr_up);
+ }
+ local_irq_restore(flags);
+}
+
+/*
+ * called from process.c:copy_thread(). task is new child.
+ */
+void
+pfm_inherit(struct task_struct *task, struct pt_regs *regs)
+{
+ struct thread_struct *thread;
+
+ DPRINT(("perfmon: pfm_inherit clearing state for [%d]\n", task->pid));
+
+ thread = &task->thread;
+
+ /*
+ * cut links inherited from parent (current)
+ */
+ thread->pfm_context = NULL;
+
+ PFM_SET_WORK_PENDING(task, 0);
+
+ /*
+ * the psr bits are already set properly in copy_threads()
+ */
+}
+#else /* !CONFIG_PERFMON */
+asmlinkage long
+sys_perfmonctl (int fd, int cmd, void *arg, int count)
+{
+ return -ENOSYS;
+}
+#endif /* CONFIG_PERFMON */