|  | /* -*- mode: c; c-basic-offset: 8; -*- | 
|  | * vim: noexpandtab sw=8 ts=8 sts=0: | 
|  | * | 
|  | * Copyright (C) 2005 Oracle.  All rights reserved. | 
|  | * | 
|  | * This program is free software; you can redistribute it and/or | 
|  | * modify it under the terms of the GNU General Public | 
|  | * License as published by the Free Software Foundation; either | 
|  | * version 2 of the License, or (at your option) any later version. | 
|  | * | 
|  | * This program is distributed in the hope that it will be useful, | 
|  | * but WITHOUT ANY WARRANTY; without even the implied warranty of | 
|  | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU | 
|  | * General Public License for more details. | 
|  | * | 
|  | * You should have received a copy of the GNU General Public | 
|  | * License along with this program; if not, write to the | 
|  | * Free Software Foundation, Inc., 59 Temple Place - Suite 330, | 
|  | * Boston, MA 021110-1307, USA. | 
|  | */ | 
|  |  | 
|  | #ifndef O2CLUSTER_MASKLOG_H | 
|  | #define O2CLUSTER_MASKLOG_H | 
|  |  | 
|  | /* | 
|  | * For now this is a trivial wrapper around printk() that gives the critical | 
|  | * ability to enable sets of debugging output at run-time.  In the future this | 
|  | * will almost certainly be redirected to relayfs so that it can pay a | 
|  | * substantially lower heisenberg tax. | 
|  | * | 
|  | * Callers associate the message with a bitmask and a global bitmask is | 
|  | * maintained with help from /proc.  If any of the bits match the message is | 
|  | * output. | 
|  | * | 
|  | * We must have efficient bit tests on i386 and it seems gcc still emits crazy | 
|  | * code for the 64bit compare.  It emits very good code for the dual unsigned | 
|  | * long tests, though, completely avoiding tests that can never pass if the | 
|  | * caller gives a constant bitmask that fills one of the longs with all 0s.  So | 
|  | * the desire is to have almost all of the calls decided on by comparing just | 
|  | * one of the longs.  This leads to having infrequently given bits that are | 
|  | * frequently matched in the high bits. | 
|  | * | 
|  | * _ERROR and _NOTICE are used for messages that always go to the console and | 
|  | * have appropriate KERN_ prefixes.  We wrap these in our function instead of | 
|  | * just calling printk() so that this can eventually make its way through | 
|  | * relayfs along with the debugging messages.  Everything else gets KERN_DEBUG. | 
|  | * The inline tests and macro dance give GCC the opportunity to quite cleverly | 
|  | * only emit the appropriage printk() when the caller passes in a constant | 
|  | * mask, as is almost always the case. | 
|  | * | 
|  | * All this bitmask nonsense is managed from the files under | 
|  | * /sys/fs/o2cb/logmask/.  Reading the files gives a straightforward | 
|  | * indication of which bits are allowed (allow) or denied (off/deny). | 
|  | * 	ENTRY deny | 
|  | * 	EXIT deny | 
|  | * 	TCP off | 
|  | * 	MSG off | 
|  | * 	SOCKET off | 
|  | * 	ERROR allow | 
|  | * 	NOTICE allow | 
|  | * | 
|  | * Writing changes the state of a given bit and requires a strictly formatted | 
|  | * single write() call: | 
|  | * | 
|  | * 	write(fd, "allow", 5); | 
|  | * | 
|  | * Echoing allow/deny/off string into the logmask files can flip the bits | 
|  | * on or off as expected; here is the bash script for example: | 
|  | * | 
|  | * log_mask="/sys/fs/o2cb/log_mask" | 
|  | * for node in ENTRY EXIT TCP MSG SOCKET ERROR NOTICE; do | 
|  | *	echo allow >"$log_mask"/"$node" | 
|  | * done | 
|  | * | 
|  | * The debugfs.ocfs2 tool can also flip the bits with the -l option: | 
|  | * | 
|  | * debugfs.ocfs2 -l TCP allow | 
|  | */ | 
|  |  | 
|  | /* for task_struct */ | 
|  | #include <linux/sched.h> | 
|  |  | 
|  | /* bits that are frequently given and infrequently matched in the low word */ | 
|  | /* NOTE: If you add a flag, you need to also update masklog.c! */ | 
|  | #define ML_TCP		0x0000000000000001ULL /* net cluster/tcp.c */ | 
|  | #define ML_MSG		0x0000000000000002ULL /* net network messages */ | 
|  | #define ML_SOCKET	0x0000000000000004ULL /* net socket lifetime */ | 
|  | #define ML_HEARTBEAT	0x0000000000000008ULL /* hb all heartbeat tracking */ | 
|  | #define ML_HB_BIO	0x0000000000000010ULL /* hb io tracing */ | 
|  | #define ML_DLMFS	0x0000000000000020ULL /* dlm user dlmfs */ | 
|  | #define ML_DLM		0x0000000000000040ULL /* dlm general debugging */ | 
|  | #define ML_DLM_DOMAIN	0x0000000000000080ULL /* dlm domain debugging */ | 
|  | #define ML_DLM_THREAD	0x0000000000000100ULL /* dlm domain thread */ | 
|  | #define ML_DLM_MASTER	0x0000000000000200ULL /* dlm master functions */ | 
|  | #define ML_DLM_RECOVERY	0x0000000000000400ULL /* dlm master functions */ | 
|  | #define ML_DLM_GLUE	0x0000000000000800ULL /* ocfs2 dlm glue layer */ | 
|  | #define ML_VOTE		0x0000000000001000ULL /* ocfs2 node messaging  */ | 
|  | #define ML_CONN		0x0000000000002000ULL /* net connection management */ | 
|  | #define ML_QUORUM	0x0000000000004000ULL /* net connection quorum */ | 
|  | #define ML_BASTS	0x0000000000008000ULL /* dlmglue asts and basts */ | 
|  | #define ML_CLUSTER	0x0000000000010000ULL /* cluster stack */ | 
|  |  | 
|  | /* bits that are infrequently given and frequently matched in the high word */ | 
|  | #define ML_ERROR	0x1000000000000000ULL /* sent to KERN_ERR */ | 
|  | #define ML_NOTICE	0x2000000000000000ULL /* setn to KERN_NOTICE */ | 
|  | #define ML_KTHREAD	0x4000000000000000ULL /* kernel thread activity */ | 
|  |  | 
|  | #define MLOG_INITIAL_AND_MASK (ML_ERROR|ML_NOTICE) | 
|  | #ifndef MLOG_MASK_PREFIX | 
|  | #define MLOG_MASK_PREFIX 0 | 
|  | #endif | 
|  |  | 
|  | /* | 
|  | * When logging is disabled, force the bit test to 0 for anything other | 
|  | * than errors and notices, allowing gcc to remove the code completely. | 
|  | * When enabled, allow all masks. | 
|  | */ | 
|  | #if defined(CONFIG_OCFS2_DEBUG_MASKLOG) | 
|  | #define ML_ALLOWED_BITS ~0 | 
|  | #else | 
|  | #define ML_ALLOWED_BITS (ML_ERROR|ML_NOTICE) | 
|  | #endif | 
|  |  | 
|  | #define MLOG_MAX_BITS 64 | 
|  |  | 
|  | struct mlog_bits { | 
|  | unsigned long words[MLOG_MAX_BITS / BITS_PER_LONG]; | 
|  | }; | 
|  |  | 
|  | extern struct mlog_bits mlog_and_bits, mlog_not_bits; | 
|  |  | 
|  | #if BITS_PER_LONG == 32 | 
|  |  | 
|  | #define __mlog_test_u64(mask, bits)			\ | 
|  | ( (u32)(mask & 0xffffffff) & bits.words[0] || 	\ | 
|  | ((u64)(mask) >> 32) & bits.words[1] ) | 
|  | #define __mlog_set_u64(mask, bits) do {			\ | 
|  | bits.words[0] |= (u32)(mask & 0xffffffff);	\ | 
|  | bits.words[1] |= (u64)(mask) >> 32;		\ | 
|  | } while (0) | 
|  | #define __mlog_clear_u64(mask, bits) do {		\ | 
|  | bits.words[0] &= ~((u32)(mask & 0xffffffff));	\ | 
|  | bits.words[1] &= ~((u64)(mask) >> 32);		\ | 
|  | } while (0) | 
|  | #define MLOG_BITS_RHS(mask) {				\ | 
|  | {						\ | 
|  | [0] = (u32)(mask & 0xffffffff),		\ | 
|  | [1] = (u64)(mask) >> 32,		\ | 
|  | }						\ | 
|  | } | 
|  |  | 
|  | #else /* 32bit long above, 64bit long below */ | 
|  |  | 
|  | #define __mlog_test_u64(mask, bits)	((mask) & bits.words[0]) | 
|  | #define __mlog_set_u64(mask, bits) do {		\ | 
|  | bits.words[0] |= (mask);		\ | 
|  | } while (0) | 
|  | #define __mlog_clear_u64(mask, bits) do {	\ | 
|  | bits.words[0] &= ~(mask);		\ | 
|  | } while (0) | 
|  | #define MLOG_BITS_RHS(mask) { { (mask) } } | 
|  |  | 
|  | #endif | 
|  |  | 
|  | /* | 
|  | * smp_processor_id() "helpfully" screams when called outside preemptible | 
|  | * regions in current kernels.  sles doesn't have the variants that don't | 
|  | * scream.  just do this instead of trying to guess which we're building | 
|  | * against.. *sigh*. | 
|  | */ | 
|  | #define __mlog_cpu_guess ({		\ | 
|  | unsigned long _cpu = get_cpu();	\ | 
|  | put_cpu();			\ | 
|  | _cpu;				\ | 
|  | }) | 
|  |  | 
|  | /* In the following two macros, the whitespace after the ',' just | 
|  | * before ##args is intentional. Otherwise, gcc 2.95 will eat the | 
|  | * previous token if args expands to nothing. | 
|  | */ | 
|  | #define __mlog_printk(level, fmt, args...)				\ | 
|  | printk(level "(%s,%u,%lu):%s:%d " fmt, current->comm,		\ | 
|  | task_pid_nr(current), __mlog_cpu_guess,			\ | 
|  | __PRETTY_FUNCTION__, __LINE__ , ##args) | 
|  |  | 
|  | #define mlog(mask, fmt, args...) do {					\ | 
|  | u64 __m = MLOG_MASK_PREFIX | (mask);				\ | 
|  | if ((__m & ML_ALLOWED_BITS) &&					\ | 
|  | __mlog_test_u64(__m, mlog_and_bits) &&			\ | 
|  | !__mlog_test_u64(__m, mlog_not_bits)) {			\ | 
|  | if (__m & ML_ERROR)					\ | 
|  | __mlog_printk(KERN_ERR, "ERROR: "fmt , ##args);	\ | 
|  | else if (__m & ML_NOTICE)				\ | 
|  | __mlog_printk(KERN_NOTICE, fmt , ##args);	\ | 
|  | else __mlog_printk(KERN_INFO, fmt , ##args);		\ | 
|  | }								\ | 
|  | } while (0) | 
|  |  | 
|  | #define mlog_errno(st) do {						\ | 
|  | int _st = (st);							\ | 
|  | if (_st != -ERESTARTSYS && _st != -EINTR &&			\ | 
|  | _st != AOP_TRUNCATED_PAGE && _st != -ENOSPC)		\ | 
|  | mlog(ML_ERROR, "status = %lld\n", (long long)_st);	\ | 
|  | } while (0) | 
|  |  | 
|  | #define mlog_bug_on_msg(cond, fmt, args...) do {			\ | 
|  | if (cond) {							\ | 
|  | mlog(ML_ERROR, "bug expression: " #cond "\n");		\ | 
|  | mlog(ML_ERROR, fmt, ##args);				\ | 
|  | BUG();							\ | 
|  | }								\ | 
|  | } while (0) | 
|  |  | 
|  | #include <linux/kobject.h> | 
|  | #include <linux/sysfs.h> | 
|  | int mlog_sys_init(struct kset *o2cb_subsys); | 
|  | void mlog_sys_shutdown(void); | 
|  |  | 
|  | #endif /* O2CLUSTER_MASKLOG_H */ |