xref: /openbmc/linux/fs/ocfs2/cluster/masklog.h (revision f42b3800)
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  *
51  * All this bitmask nonsense is hidden from the /proc interface so that Joel
52  * doesn't have an aneurism.  Reading the file gives a straight forward
53  * indication of which bits are on or off:
54  * 	ENTRY off
55  * 	EXIT off
56  * 	TCP off
57  * 	MSG off
58  * 	SOCKET off
59  * 	ERROR off
60  * 	NOTICE on
61  *
62  * Writing changes the state of a given bit and requires a strictly formatted
63  * single write() call:
64  *
65  * 	write(fd, "ENTRY on", 8);
66  *
67  * would turn the entry bit on.  "1" is also accepted in the place of "on", and
68  * "off" and "0" behave as expected.
69  *
70  * Some trivial shell can flip all the bits on or off:
71  *
72  * log_mask="/proc/fs/ocfs2_nodemanager/log_mask"
73  * cat $log_mask | (
74  * 	while read bit status; do
75  * 		# $1 is "on" or "off", say
76  * 		echo "$bit $1" > $log_mask
77  * 	done
78  * )
79  */
80 
81 /* for task_struct */
82 #include <linux/sched.h>
83 
84 /* bits that are frequently given and infrequently matched in the low word */
85 /* NOTE: If you add a flag, you need to also update mlog.c! */
86 #define ML_ENTRY	0x0000000000000001ULL /* func call entry */
87 #define ML_EXIT		0x0000000000000002ULL /* func call exit */
88 #define ML_TCP		0x0000000000000004ULL /* net cluster/tcp.c */
89 #define ML_MSG		0x0000000000000008ULL /* net network messages */
90 #define ML_SOCKET	0x0000000000000010ULL /* net socket lifetime */
91 #define ML_HEARTBEAT	0x0000000000000020ULL /* hb all heartbeat tracking */
92 #define ML_HB_BIO	0x0000000000000040ULL /* hb io tracing */
93 #define ML_DLMFS	0x0000000000000080ULL /* dlm user dlmfs */
94 #define ML_DLM		0x0000000000000100ULL /* dlm general debugging */
95 #define ML_DLM_DOMAIN	0x0000000000000200ULL /* dlm domain debugging */
96 #define ML_DLM_THREAD	0x0000000000000400ULL /* dlm domain thread */
97 #define ML_DLM_MASTER	0x0000000000000800ULL /* dlm master functions */
98 #define ML_DLM_RECOVERY	0x0000000000001000ULL /* dlm master functions */
99 #define ML_AIO		0x0000000000002000ULL /* ocfs2 aio read and write */
100 #define ML_JOURNAL	0x0000000000004000ULL /* ocfs2 journalling functions */
101 #define ML_DISK_ALLOC	0x0000000000008000ULL /* ocfs2 disk allocation */
102 #define ML_SUPER	0x0000000000010000ULL /* ocfs2 mount / umount */
103 #define ML_FILE_IO	0x0000000000020000ULL /* ocfs2 file I/O */
104 #define ML_EXTENT_MAP	0x0000000000040000ULL /* ocfs2 extent map caching */
105 #define ML_DLM_GLUE	0x0000000000080000ULL /* ocfs2 dlm glue layer */
106 #define ML_BH_IO	0x0000000000100000ULL /* ocfs2 buffer I/O */
107 #define ML_UPTODATE	0x0000000000200000ULL /* ocfs2 caching sequence #'s */
108 #define ML_NAMEI	0x0000000000400000ULL /* ocfs2 directory / namespace */
109 #define ML_INODE	0x0000000000800000ULL /* ocfs2 inode manipulation */
110 #define ML_VOTE		0x0000000001000000ULL /* ocfs2 node messaging  */
111 #define ML_DCACHE	0x0000000002000000ULL /* ocfs2 dcache operations */
112 #define ML_CONN		0x0000000004000000ULL /* net connection management */
113 #define ML_QUORUM	0x0000000008000000ULL /* net connection quorum */
114 #define ML_EXPORT	0x0000000010000000ULL /* ocfs2 export operations */
115 /* bits that are infrequently given and frequently matched in the high word */
116 #define ML_ERROR	0x0000000100000000ULL /* sent to KERN_ERR */
117 #define ML_NOTICE	0x0000000200000000ULL /* setn to KERN_NOTICE */
118 #define ML_KTHREAD	0x0000000400000000ULL /* kernel thread activity */
119 
120 #define MLOG_INITIAL_AND_MASK (ML_ERROR|ML_NOTICE)
121 #define MLOG_INITIAL_NOT_MASK (ML_ENTRY|ML_EXIT)
122 #ifndef MLOG_MASK_PREFIX
123 #define MLOG_MASK_PREFIX 0
124 #endif
125 
126 /*
127  * When logging is disabled, force the bit test to 0 for anything other
128  * than errors and notices, allowing gcc to remove the code completely.
129  * When enabled, allow all masks.
130  */
131 #if defined(CONFIG_OCFS2_DEBUG_MASKLOG)
132 #define ML_ALLOWED_BITS ~0
133 #else
134 #define ML_ALLOWED_BITS (ML_ERROR|ML_NOTICE)
135 #endif
136 
137 #define MLOG_MAX_BITS 64
138 
139 struct mlog_bits {
140 	unsigned long words[MLOG_MAX_BITS / BITS_PER_LONG];
141 };
142 
143 extern struct mlog_bits mlog_and_bits, mlog_not_bits;
144 
145 #if BITS_PER_LONG == 32
146 
147 #define __mlog_test_u64(mask, bits)			\
148 	( (u32)(mask & 0xffffffff) & bits.words[0] || 	\
149 	  ((u64)(mask) >> 32) & bits.words[1] )
150 #define __mlog_set_u64(mask, bits) do {			\
151 	bits.words[0] |= (u32)(mask & 0xffffffff);	\
152        	bits.words[1] |= (u64)(mask) >> 32;		\
153 } while (0)
154 #define __mlog_clear_u64(mask, bits) do {		\
155 	bits.words[0] &= ~((u32)(mask & 0xffffffff));	\
156        	bits.words[1] &= ~((u64)(mask) >> 32);		\
157 } while (0)
158 #define MLOG_BITS_RHS(mask) {				\
159 	{						\
160 		[0] = (u32)(mask & 0xffffffff),		\
161 		[1] = (u64)(mask) >> 32,		\
162 	}						\
163 }
164 
165 #else /* 32bit long above, 64bit long below */
166 
167 #define __mlog_test_u64(mask, bits)	((mask) & bits.words[0])
168 #define __mlog_set_u64(mask, bits) do {		\
169 	bits.words[0] |= (mask);		\
170 } while (0)
171 #define __mlog_clear_u64(mask, bits) do {	\
172 	bits.words[0] &= ~(mask);		\
173 } while (0)
174 #define MLOG_BITS_RHS(mask) { { (mask) } }
175 
176 #endif
177 
178 /*
179  * smp_processor_id() "helpfully" screams when called outside preemptible
180  * regions in current kernels.  sles doesn't have the variants that don't
181  * scream.  just do this instead of trying to guess which we're building
182  * against.. *sigh*.
183  */
184 #define __mlog_cpu_guess ({		\
185 	unsigned long _cpu = get_cpu();	\
186 	put_cpu();			\
187 	_cpu;				\
188 })
189 
190 /* In the following two macros, the whitespace after the ',' just
191  * before ##args is intentional. Otherwise, gcc 2.95 will eat the
192  * previous token if args expands to nothing.
193  */
194 #define __mlog_printk(level, fmt, args...)				\
195 	printk(level "(%u,%lu):%s:%d " fmt, task_pid_nr(current),	\
196 	       __mlog_cpu_guess, __PRETTY_FUNCTION__, __LINE__ ,	\
197 	       ##args)
198 
199 #define mlog(mask, fmt, args...) do {					\
200 	u64 __m = MLOG_MASK_PREFIX | (mask);				\
201 	if ((__m & ML_ALLOWED_BITS) &&					\
202 	    __mlog_test_u64(__m, mlog_and_bits) &&			\
203 	    !__mlog_test_u64(__m, mlog_not_bits)) {			\
204 		if (__m & ML_ERROR)					\
205 			__mlog_printk(KERN_ERR, "ERROR: "fmt , ##args);	\
206 		else if (__m & ML_NOTICE)				\
207 			__mlog_printk(KERN_NOTICE, fmt , ##args);	\
208 		else __mlog_printk(KERN_INFO, fmt , ##args);		\
209 	}								\
210 } while (0)
211 
212 #define mlog_errno(st) do {						\
213 	int _st = (st);							\
214 	if (_st != -ERESTARTSYS && _st != -EINTR &&			\
215 	    _st != AOP_TRUNCATED_PAGE && _st != -ENOSPC)		\
216 		mlog(ML_ERROR, "status = %lld\n", (long long)_st);	\
217 } while (0)
218 
219 #if defined(CONFIG_OCFS2_DEBUG_MASKLOG)
220 #define mlog_entry(fmt, args...) do {					\
221 	mlog(ML_ENTRY, "ENTRY:" fmt , ##args);				\
222 } while (0)
223 
224 #define mlog_entry_void() do {						\
225 	mlog(ML_ENTRY, "ENTRY:\n");					\
226 } while (0)
227 
228 /*
229  * We disable this for sparse.
230  */
231 #if !defined(__CHECKER__)
232 #define mlog_exit(st) do {						     \
233 	if (__builtin_types_compatible_p(typeof(st), unsigned long))	     \
234 		mlog(ML_EXIT, "EXIT: %lu\n", (unsigned long) (st));	     \
235 	else if (__builtin_types_compatible_p(typeof(st), signed long))      \
236 		mlog(ML_EXIT, "EXIT: %ld\n", (signed long) (st));	     \
237 	else if (__builtin_types_compatible_p(typeof(st), unsigned int)	     \
238 		 || __builtin_types_compatible_p(typeof(st), unsigned short) \
239 		 || __builtin_types_compatible_p(typeof(st), unsigned char)) \
240 		mlog(ML_EXIT, "EXIT: %u\n", (unsigned int) (st));	     \
241 	else if (__builtin_types_compatible_p(typeof(st), signed int)	     \
242 		 || __builtin_types_compatible_p(typeof(st), signed short)   \
243 		 || __builtin_types_compatible_p(typeof(st), signed char))   \
244 		mlog(ML_EXIT, "EXIT: %d\n", (signed int) (st));		     \
245 	else if (__builtin_types_compatible_p(typeof(st), long long))	     \
246 		mlog(ML_EXIT, "EXIT: %lld\n", (long long) (st));	     \
247 	else								     \
248 		mlog(ML_EXIT, "EXIT: %llu\n", (unsigned long long) (st));    \
249 } while (0)
250 #else
251 #define mlog_exit(st) do {						     \
252 	mlog(ML_EXIT, "EXIT: %lld\n", (long long) (st));		     \
253 } while (0)
254 #endif
255 
256 #define mlog_exit_ptr(ptr) do {						\
257 	mlog(ML_EXIT, "EXIT: %p\n", ptr);				\
258 } while (0)
259 
260 #define mlog_exit_void() do {						\
261 	mlog(ML_EXIT, "EXIT\n");					\
262 } while (0)
263 #else
264 #define mlog_entry(...)  do { } while (0)
265 #define mlog_entry_void(...)  do { } while (0)
266 #define mlog_exit(...)  do { } while (0)
267 #define mlog_exit_ptr(...)  do { } while (0)
268 #define mlog_exit_void(...)  do { } while (0)
269 #endif  /* defined(CONFIG_OCFS2_DEBUG_MASKLOG) */
270 
271 #define mlog_bug_on_msg(cond, fmt, args...) do {			\
272 	if (cond) {							\
273 		mlog(ML_ERROR, "bug expression: " #cond "\n");		\
274 		mlog(ML_ERROR, fmt, ##args);				\
275 		BUG();							\
276 	}								\
277 } while (0)
278 
279 #include <linux/kobject.h>
280 #include <linux/sysfs.h>
281 int mlog_sys_init(struct kset *o2cb_subsys);
282 void mlog_sys_shutdown(void);
283 
284 #endif /* O2CLUSTER_MASKLOG_H */
285