x86: convert to generic helpers for IPI function calls
This converts x86, x86-64, and xen to use the new helpers for
smp_call_function() and friends, and adds support for
smp_call_function_single().
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/arch/x86/kernel/apic_32.c b/arch/x86/kernel/apic_32.c
index 4b99b1b..71017f7 100644
--- a/arch/x86/kernel/apic_32.c
+++ b/arch/x86/kernel/apic_32.c
@@ -1358,6 +1358,10 @@
/* IPI for generic function call */
set_intr_gate(CALL_FUNCTION_VECTOR, call_function_interrupt);
+
+ /* IPI for single call function */
+ set_intr_gate(CALL_FUNCTION_SINGLE_VECTOR,
+ call_function_single_interrupt);
}
#endif
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index 556a8df..6d1fe27 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -711,6 +711,9 @@
ENTRY(call_function_interrupt)
apicinterrupt CALL_FUNCTION_VECTOR,smp_call_function_interrupt
END(call_function_interrupt)
+ENTRY(call_function_single_interrupt)
+ apicinterrupt CALL_FUNCTION_SINGLE_VECTOR,smp_call_function_single_interrupt
+END(call_function_single_interrupt)
ENTRY(irq_move_cleanup_interrupt)
apicinterrupt IRQ_MOVE_CLEANUP_VECTOR,smp_irq_move_cleanup_interrupt
END(irq_move_cleanup_interrupt)
diff --git a/arch/x86/kernel/i8259_64.c b/arch/x86/kernel/i8259_64.c
index fa57a15..00d2ccd 100644
--- a/arch/x86/kernel/i8259_64.c
+++ b/arch/x86/kernel/i8259_64.c
@@ -494,6 +494,10 @@
/* IPI for generic function call */
set_intr_gate(CALL_FUNCTION_VECTOR, call_function_interrupt);
+ /* IPI for generic single function call */
+ set_intr_gate(CALL_FUNCTION_SINGLE_VECTOR,
+ call_function_single_interrupt);
+
/* Low priority IPI to cleanup after moving an irq */
set_intr_gate(IRQ_MOVE_CLEANUP_VECTOR, irq_move_cleanup_interrupt);
#endif
diff --git a/arch/x86/kernel/smp.c b/arch/x86/kernel/smp.c
index 0cb7aad..575aa3d 100644
--- a/arch/x86/kernel/smp.c
+++ b/arch/x86/kernel/smp.c
@@ -121,132 +121,23 @@
send_IPI_mask(cpumask_of_cpu(cpu), RESCHEDULE_VECTOR);
}
-/*
- * Structure and data for smp_call_function(). This is designed to minimise
- * static memory requirements. It also looks cleaner.
- */
-static DEFINE_SPINLOCK(call_lock);
-
-struct call_data_struct {
- void (*func) (void *info);
- void *info;
- atomic_t started;
- atomic_t finished;
- int wait;
-};
-
-void lock_ipi_call_lock(void)
+void native_send_call_func_single_ipi(int cpu)
{
- spin_lock_irq(&call_lock);
+ send_IPI_mask(cpumask_of_cpu(cpu), CALL_FUNCTION_SINGLE_VECTOR);
}
-void unlock_ipi_call_lock(void)
+void native_send_call_func_ipi(cpumask_t mask)
{
- spin_unlock_irq(&call_lock);
-}
-
-static struct call_data_struct *call_data;
-
-static void __smp_call_function(void (*func) (void *info), void *info,
- int nonatomic, int wait)
-{
- struct call_data_struct data;
- int cpus = num_online_cpus() - 1;
-
- if (!cpus)
- return;
-
- data.func = func;
- data.info = info;
- atomic_set(&data.started, 0);
- data.wait = wait;
- if (wait)
- atomic_set(&data.finished, 0);
-
- call_data = &data;
- mb();
-
- /* Send a message to all other CPUs and wait for them to respond */
- send_IPI_allbutself(CALL_FUNCTION_VECTOR);
-
- /* Wait for response */
- while (atomic_read(&data.started) != cpus)
- cpu_relax();
-
- if (wait)
- while (atomic_read(&data.finished) != cpus)
- cpu_relax();
-}
-
-
-/**
- * smp_call_function_mask(): Run a function on a set of other CPUs.
- * @mask: The set of cpus to run on. Must not include the current cpu.
- * @func: The function to run. This must be fast and non-blocking.
- * @info: An arbitrary pointer to pass to the function.
- * @wait: If true, wait (atomically) until function has completed on other CPUs.
- *
- * Returns 0 on success, else a negative status code.
- *
- * If @wait is true, then returns once @func has returned; otherwise
- * it returns just before the target cpu calls @func.
- *
- * You must not call this function with disabled interrupts or from a
- * hardware interrupt handler or from a bottom half handler.
- */
-static int
-native_smp_call_function_mask(cpumask_t mask,
- void (*func)(void *), void *info,
- int wait)
-{
- struct call_data_struct data;
cpumask_t allbutself;
- int cpus;
-
- /* Can deadlock when called with interrupts disabled */
- WARN_ON(irqs_disabled());
-
- /* Holding any lock stops cpus from going down. */
- spin_lock(&call_lock);
allbutself = cpu_online_map;
cpu_clear(smp_processor_id(), allbutself);
- cpus_and(mask, mask, allbutself);
- cpus = cpus_weight(mask);
-
- if (!cpus) {
- spin_unlock(&call_lock);
- return 0;
- }
-
- data.func = func;
- data.info = info;
- atomic_set(&data.started, 0);
- data.wait = wait;
- if (wait)
- atomic_set(&data.finished, 0);
-
- call_data = &data;
- wmb();
-
- /* Send a message to other CPUs */
if (cpus_equal(mask, allbutself) &&
cpus_equal(cpu_online_map, cpu_callout_map))
send_IPI_allbutself(CALL_FUNCTION_VECTOR);
else
send_IPI_mask(mask, CALL_FUNCTION_VECTOR);
-
- /* Wait for response */
- while (atomic_read(&data.started) != cpus)
- cpu_relax();
-
- if (wait)
- while (atomic_read(&data.finished) != cpus)
- cpu_relax();
- spin_unlock(&call_lock);
-
- return 0;
}
static void stop_this_cpu(void *dummy)
@@ -268,18 +159,13 @@
static void native_smp_send_stop(void)
{
- int nolock;
unsigned long flags;
if (reboot_force)
return;
- /* Don't deadlock on the call lock in panic */
- nolock = !spin_trylock(&call_lock);
+ smp_call_function(stop_this_cpu, NULL, 0, 0);
local_irq_save(flags);
- __smp_call_function(stop_this_cpu, NULL, 0, 0);
- if (!nolock)
- spin_unlock(&call_lock);
disable_local_APIC();
local_irq_restore(flags);
}
@@ -301,33 +187,28 @@
void smp_call_function_interrupt(struct pt_regs *regs)
{
- void (*func) (void *info) = call_data->func;
- void *info = call_data->info;
- int wait = call_data->wait;
-
ack_APIC_irq();
- /*
- * Notify initiating CPU that I've grabbed the data and am
- * about to execute the function
- */
- mb();
- atomic_inc(&call_data->started);
- /*
- * At this point the info structure may be out of scope unless wait==1
- */
irq_enter();
- (*func)(info);
+ generic_smp_call_function_interrupt();
#ifdef CONFIG_X86_32
__get_cpu_var(irq_stat).irq_call_count++;
#else
add_pda(irq_call_count, 1);
#endif
irq_exit();
+}
- if (wait) {
- mb();
- atomic_inc(&call_data->finished);
- }
+void smp_call_function_single_interrupt(void)
+{
+ ack_APIC_irq();
+ irq_enter();
+ generic_smp_call_function_single_interrupt();
+#ifdef CONFIG_X86_32
+ __get_cpu_var(irq_stat).irq_call_count++;
+#else
+ add_pda(irq_call_count, 1);
+#endif
+ irq_exit();
}
struct smp_ops smp_ops = {
@@ -338,7 +219,8 @@
.smp_send_stop = native_smp_send_stop,
.smp_send_reschedule = native_smp_send_reschedule,
- .smp_call_function_mask = native_smp_call_function_mask,
+
+ .send_call_func_ipi = native_send_call_func_ipi,
+ .send_call_func_single_ipi = native_send_call_func_single_ipi,
};
EXPORT_SYMBOL_GPL(smp_ops);
-
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 56078d6..8964789 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -345,7 +345,7 @@
* lock helps us to not include this cpu in a currently in progress
* smp_call_function().
*/
- lock_ipi_call_lock();
+ ipi_call_lock_irq();
#ifdef CONFIG_X86_64
spin_lock(&vector_lock);
@@ -357,7 +357,7 @@
spin_unlock(&vector_lock);
#endif
cpu_set(smp_processor_id(), cpu_online_map);
- unlock_ipi_call_lock();
+ ipi_call_unlock_irq();
per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE;
setup_secondary_clock();
diff --git a/arch/x86/kernel/smpcommon.c b/arch/x86/kernel/smpcommon.c
index 3449064..99941b3 100644
--- a/arch/x86/kernel/smpcommon.c
+++ b/arch/x86/kernel/smpcommon.c
@@ -25,59 +25,3 @@
per_cpu(cpu_number, cpu) = cpu;
}
#endif
-
-/**
- * smp_call_function(): Run a function on all other CPUs.
- * @func: The function to run. This must be fast and non-blocking.
- * @info: An arbitrary pointer to pass to the function.
- * @nonatomic: Unused.
- * @wait: If true, wait (atomically) until function has completed on other CPUs.
- *
- * Returns 0 on success, else a negative status code.
- *
- * If @wait is true, then returns once @func has returned; otherwise
- * it returns just before the target cpu calls @func.
- *
- * You must not call this function with disabled interrupts or from a
- * hardware interrupt handler or from a bottom half handler.
- */
-int smp_call_function(void (*func) (void *info), void *info, int nonatomic,
- int wait)
-{
- return smp_call_function_mask(cpu_online_map, func, info, wait);
-}
-EXPORT_SYMBOL(smp_call_function);
-
-/**
- * smp_call_function_single - Run a function on a specific CPU
- * @cpu: The target CPU. Cannot be the calling CPU.
- * @func: The function to run. This must be fast and non-blocking.
- * @info: An arbitrary pointer to pass to the function.
- * @nonatomic: Unused.
- * @wait: If true, wait until function has completed on other CPUs.
- *
- * Returns 0 on success, else a negative status code.
- *
- * If @wait is true, then returns once @func has returned; otherwise
- * it returns just before the target cpu calls @func.
- */
-int smp_call_function_single(int cpu, void (*func) (void *info), void *info,
- int nonatomic, int wait)
-{
- /* prevent preemption and reschedule on another processor */
- int ret;
- int me = get_cpu();
- if (cpu == me) {
- local_irq_disable();
- func(info);
- local_irq_enable();
- put_cpu();
- return 0;
- }
-
- ret = smp_call_function_mask(cpumask_of_cpu(cpu), func, info, wait);
-
- put_cpu();
- return ret;
-}
-EXPORT_SYMBOL(smp_call_function_single);