| /* -*- 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) ({ \ |
| 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 */ |