ocfs2: Remove masklog ML_NAMEI.
[linux-block.git] / fs / ocfs2 / cluster / masklog.h
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1/* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
3 *
4 * Copyright (C) 2005 Oracle. All rights reserved.
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public
17 * License along with this program; if not, write to the
18 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19 * Boston, MA 021110-1307, USA.
20 */
21
22#ifndef O2CLUSTER_MASKLOG_H
23#define O2CLUSTER_MASKLOG_H
24
25/*
26 * For now this is a trivial wrapper around printk() that gives the critical
27 * ability to enable sets of debugging output at run-time. In the future this
28 * will almost certainly be redirected to relayfs so that it can pay a
29 * substantially lower heisenberg tax.
30 *
31 * Callers associate the message with a bitmask and a global bitmask is
32 * maintained with help from /proc. If any of the bits match the message is
33 * output.
34 *
35 * We must have efficient bit tests on i386 and it seems gcc still emits crazy
36 * code for the 64bit compare. It emits very good code for the dual unsigned
37 * long tests, though, completely avoiding tests that can never pass if the
38 * caller gives a constant bitmask that fills one of the longs with all 0s. So
39 * the desire is to have almost all of the calls decided on by comparing just
40 * one of the longs. This leads to having infrequently given bits that are
41 * frequently matched in the high bits.
42 *
43 * _ERROR and _NOTICE are used for messages that always go to the console and
44 * have appropriate KERN_ prefixes. We wrap these in our function instead of
45 * just calling printk() so that this can eventually make its way through
46 * relayfs along with the debugging messages. Everything else gets KERN_DEBUG.
47 * The inline tests and macro dance give GCC the opportunity to quite cleverly
48 * only emit the appropriage printk() when the caller passes in a constant
49 * mask, as is almost always the case.
50 *
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51 * All this bitmask nonsense is managed from the files under
52 * /sys/fs/o2cb/logmask/. Reading the files gives a straightforward
53 * indication of which bits are allowed (allow) or denied (off/deny).
54 * ENTRY deny
55 * EXIT deny
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56 * TCP off
57 * MSG off
58 * SOCKET off
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59 * ERROR allow
60 * NOTICE allow
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61 *
62 * Writing changes the state of a given bit and requires a strictly formatted
63 * single write() call:
64 *
2b53bc7b 65 * write(fd, "allow", 5);
52fd3d6f 66 *
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67 * Echoing allow/deny/off string into the logmask files can flip the bits
68 * on or off as expected; here is the bash script for example:
52fd3d6f 69 *
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70 * log_mask="/sys/fs/o2cb/log_mask"
71 * for node in ENTRY EXIT TCP MSG SOCKET ERROR NOTICE; do
72 * echo allow >"$log_mask"/"$node"
73 * done
52fd3d6f 74 *
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75 * The debugfs.ocfs2 tool can also flip the bits with the -l option:
76 *
77 * debugfs.ocfs2 -l TCP allow
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78 */
79
80/* for task_struct */
81#include <linux/sched.h>
82
83/* bits that are frequently given and infrequently matched in the low word */
41b41a26 84/* NOTE: If you add a flag, you need to also update masklog.c! */
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85#define ML_TCP 0x0000000000000004ULL /* net cluster/tcp.c */
86#define ML_MSG 0x0000000000000008ULL /* net network messages */
87#define ML_SOCKET 0x0000000000000010ULL /* net socket lifetime */
88#define ML_HEARTBEAT 0x0000000000000020ULL /* hb all heartbeat tracking */
89#define ML_HB_BIO 0x0000000000000040ULL /* hb io tracing */
90#define ML_DLMFS 0x0000000000000080ULL /* dlm user dlmfs */
91#define ML_DLM 0x0000000000000100ULL /* dlm general debugging */
92#define ML_DLM_DOMAIN 0x0000000000000200ULL /* dlm domain debugging */
93#define ML_DLM_THREAD 0x0000000000000400ULL /* dlm domain thread */
94#define ML_DLM_MASTER 0x0000000000000800ULL /* dlm master functions */
95#define ML_DLM_RECOVERY 0x0000000000001000ULL /* dlm master functions */
96#define ML_AIO 0x0000000000002000ULL /* ocfs2 aio read and write */
97#define ML_JOURNAL 0x0000000000004000ULL /* ocfs2 journalling functions */
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98#define ML_DLM_GLUE 0x0000000000080000ULL /* ocfs2 dlm glue layer */
99#define ML_BH_IO 0x0000000000100000ULL /* ocfs2 buffer I/O */
100#define ML_UPTODATE 0x0000000000200000ULL /* ocfs2 caching sequence #'s */
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101#define ML_VOTE 0x0000000001000000ULL /* ocfs2 node messaging */
102#define ML_DCACHE 0x0000000002000000ULL /* ocfs2 dcache operations */
103#define ML_CONN 0x0000000004000000ULL /* net connection management */
104#define ML_QUORUM 0x0000000008000000ULL /* net connection quorum */
105#define ML_EXPORT 0x0000000010000000ULL /* ocfs2 export operations */
41b41a26 106#define ML_BASTS 0x0000000100000000ULL /* dlmglue asts and basts */
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107#define ML_CLUSTER 0x0000000400000000ULL /* cluster stack */
108
52fd3d6f 109/* bits that are infrequently given and frequently matched in the high word */
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110#define ML_ERROR 0x1000000000000000ULL /* sent to KERN_ERR */
111#define ML_NOTICE 0x2000000000000000ULL /* setn to KERN_NOTICE */
112#define ML_KTHREAD 0x4000000000000000ULL /* kernel thread activity */
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113
114#define MLOG_INITIAL_AND_MASK (ML_ERROR|ML_NOTICE)
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115#ifndef MLOG_MASK_PREFIX
116#define MLOG_MASK_PREFIX 0
117#endif
118
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119/*
120 * When logging is disabled, force the bit test to 0 for anything other
121 * than errors and notices, allowing gcc to remove the code completely.
122 * When enabled, allow all masks.
123 */
124#if defined(CONFIG_OCFS2_DEBUG_MASKLOG)
125#define ML_ALLOWED_BITS ~0
126#else
127#define ML_ALLOWED_BITS (ML_ERROR|ML_NOTICE)
128#endif
129
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130#define MLOG_MAX_BITS 64
131
132struct mlog_bits {
133 unsigned long words[MLOG_MAX_BITS / BITS_PER_LONG];
134};
135
136extern struct mlog_bits mlog_and_bits, mlog_not_bits;
137
138#if BITS_PER_LONG == 32
139
140#define __mlog_test_u64(mask, bits) \
141 ( (u32)(mask & 0xffffffff) & bits.words[0] || \
142 ((u64)(mask) >> 32) & bits.words[1] )
143#define __mlog_set_u64(mask, bits) do { \
144 bits.words[0] |= (u32)(mask & 0xffffffff); \
145 bits.words[1] |= (u64)(mask) >> 32; \
146} while (0)
147#define __mlog_clear_u64(mask, bits) do { \
148 bits.words[0] &= ~((u32)(mask & 0xffffffff)); \
149 bits.words[1] &= ~((u64)(mask) >> 32); \
150} while (0)
151#define MLOG_BITS_RHS(mask) { \
152 { \
153 [0] = (u32)(mask & 0xffffffff), \
154 [1] = (u64)(mask) >> 32, \
155 } \
156}
157
158#else /* 32bit long above, 64bit long below */
159
160#define __mlog_test_u64(mask, bits) ((mask) & bits.words[0])
161#define __mlog_set_u64(mask, bits) do { \
162 bits.words[0] |= (mask); \
163} while (0)
164#define __mlog_clear_u64(mask, bits) do { \
165 bits.words[0] &= ~(mask); \
166} while (0)
167#define MLOG_BITS_RHS(mask) { { (mask) } }
168
169#endif
170
171/*
172 * smp_processor_id() "helpfully" screams when called outside preemptible
173 * regions in current kernels. sles doesn't have the variants that don't
174 * scream. just do this instead of trying to guess which we're building
175 * against.. *sigh*.
176 */
177#define __mlog_cpu_guess ({ \
178 unsigned long _cpu = get_cpu(); \
179 put_cpu(); \
180 _cpu; \
181})
182
183/* In the following two macros, the whitespace after the ',' just
184 * before ##args is intentional. Otherwise, gcc 2.95 will eat the
185 * previous token if args expands to nothing.
186 */
187#define __mlog_printk(level, fmt, args...) \
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188 printk(level "(%s,%u,%lu):%s:%d " fmt, current->comm, \
189 task_pid_nr(current), __mlog_cpu_guess, \
190 __PRETTY_FUNCTION__, __LINE__ , ##args)
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191
192#define mlog(mask, fmt, args...) do { \
193 u64 __m = MLOG_MASK_PREFIX | (mask); \
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194 if ((__m & ML_ALLOWED_BITS) && \
195 __mlog_test_u64(__m, mlog_and_bits) && \
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196 !__mlog_test_u64(__m, mlog_not_bits)) { \
197 if (__m & ML_ERROR) \
198 __mlog_printk(KERN_ERR, "ERROR: "fmt , ##args); \
199 else if (__m & ML_NOTICE) \
200 __mlog_printk(KERN_NOTICE, fmt , ##args); \
201 else __mlog_printk(KERN_INFO, fmt , ##args); \
202 } \
203} while (0)
204
205#define mlog_errno(st) do { \
206 int _st = (st); \
207 if (_st != -ERESTARTSYS && _st != -EINTR && \
ef9f86ce 208 _st != AOP_TRUNCATED_PAGE && _st != -ENOSPC) \
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209 mlog(ML_ERROR, "status = %lld\n", (long long)_st); \
210} while (0)
211
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212#define mlog_bug_on_msg(cond, fmt, args...) do { \
213 if (cond) { \
214 mlog(ML_ERROR, "bug expression: " #cond "\n"); \
215 mlog(ML_ERROR, fmt, ##args); \
216 BUG(); \
217 } \
218} while (0)
219
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220#include <linux/kobject.h>
221#include <linux/sysfs.h>
823bccfc 222int mlog_sys_init(struct kset *o2cb_subsys);
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223void mlog_sys_shutdown(void);
224
225#endif /* O2CLUSTER_MASKLOG_H */