linux-stable/fs/ocfs2/cluster/masklog.h
Thomas Gleixner 328970de0e treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 145
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 84 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190524100844.756442981@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:25:18 -07:00

198 lines
6.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0-or-later */
/* -*- mode: c; c-basic-offset: 8; -*-
* vim: noexpandtab sw=8 ts=8 sts=0:
*
* Copyright (C) 2005 Oracle. All rights reserved.
*/
#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
__printf(4, 5)
void __mlog_printk(const u64 *m, const char *func, int line,
const char *fmt, ...);
/*
* Testing before the __mlog_printk call lets the compiler eliminate the
* call completely when (m & ML_ALLOWED_BITS) is 0.
*/
#define mlog(mask, fmt, ...) \
do { \
u64 _m = MLOG_MASK_PREFIX | (mask); \
if (_m & ML_ALLOWED_BITS) \
__mlog_printk(&_m, __func__, __LINE__, fmt, \
##__VA_ARGS__); \
} while (0)
#define mlog_ratelimited(mask, fmt, ...) \
do { \
static DEFINE_RATELIMIT_STATE(_rs, \
DEFAULT_RATELIMIT_INTERVAL, \
DEFAULT_RATELIMIT_BURST); \
if (__ratelimit(&_rs)) \
mlog(mask, fmt, ##__VA_ARGS__); \
} while (0)
#define mlog_errno(st) ({ \
int _st = (st); \
if (_st != -ERESTARTSYS && _st != -EINTR && \
_st != AOP_TRUNCATED_PAGE && _st != -ENOSPC && \
_st != -EDQUOT) \
mlog(ML_ERROR, "status = %lld\n", (long long)_st); \
_st; \
})
#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 */