1 /*
2 * GPL HEADER START
3 *
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 only,
8 * as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License version 2 for more details (a copy is included
14 * in the LICENSE file that accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License
17 * version 2 along with this program; If not, see
18 * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
19 *
20 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
21 * CA 95054 USA or visit www.sun.com if you need additional information or
22 * have any questions.
23 *
24 * GPL HEADER END
25 */
26 /*
27 * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
28 * Use is subject to license terms.
29 *
30 * Copyright (c) 2012, Intel Corporation.
31 */
32 /*
33 * This file is part of Lustre, http://www.lustre.org/
34 * Lustre is a trademark of Sun Microsystems, Inc.
35 */
36
37 #ifndef __LIBCFS_TRACEFILE_H__
38 #define __LIBCFS_TRACEFILE_H__
39
40 #include "../../include/linux/libcfs/libcfs.h"
41
42 #include "linux/linux-tracefile.h"
43
44 /* trace file lock routines */
45
46 #define TRACEFILE_NAME_SIZE 1024
47 extern char cfs_tracefile[TRACEFILE_NAME_SIZE];
48 extern long long cfs_tracefile_size;
49
50 void libcfs_run_debug_log_upcall(char *file);
51
52 int cfs_tracefile_init_arch(void);
53 void cfs_tracefile_fini_arch(void);
54
55 void cfs_tracefile_read_lock(void);
56 void cfs_tracefile_read_unlock(void);
57 void cfs_tracefile_write_lock(void);
58 void cfs_tracefile_write_unlock(void);
59
60 int cfs_tracefile_dump_all_pages(char *filename);
61 void cfs_trace_debug_print(void);
62 void cfs_trace_flush_pages(void);
63 int cfs_trace_start_thread(void);
64 void cfs_trace_stop_thread(void);
65 int cfs_tracefile_init(int max_pages);
66 void cfs_tracefile_exit(void);
67
68 int cfs_trace_copyin_string(char *knl_buffer, int knl_buffer_nob,
69 const char __user *usr_buffer, int usr_buffer_nob);
70 int cfs_trace_copyout_string(char __user *usr_buffer, int usr_buffer_nob,
71 const char *knl_str, char *append);
72 int cfs_trace_allocate_string_buffer(char **str, int nob);
73 void cfs_trace_free_string_buffer(char *str, int nob);
74 int cfs_trace_dump_debug_buffer_usrstr(void __user *usr_str, int usr_str_nob);
75 int cfs_trace_daemon_command(char *str);
76 int cfs_trace_daemon_command_usrstr(void __user *usr_str, int usr_str_nob);
77 int cfs_trace_set_debug_mb(int mb);
78 int cfs_trace_get_debug_mb(void);
79
80 void libcfs_debug_dumplog_internal(void *arg);
81 void libcfs_register_panic_notifier(void);
82 void libcfs_unregister_panic_notifier(void);
83 extern int libcfs_panic_in_progress;
84 int cfs_trace_max_debug_mb(void);
85
86 #define TCD_MAX_PAGES (5 << (20 - PAGE_CACHE_SHIFT))
87 #define TCD_STOCK_PAGES (TCD_MAX_PAGES)
88 #define CFS_TRACEFILE_SIZE (500 << 20)
89
90 #ifdef LUSTRE_TRACEFILE_PRIVATE
91
92 /*
93 * Private declare for tracefile
94 */
95 #define TCD_MAX_PAGES (5 << (20 - PAGE_CACHE_SHIFT))
96 #define TCD_STOCK_PAGES (TCD_MAX_PAGES)
97
98 #define CFS_TRACEFILE_SIZE (500 << 20)
99
100 /* Size of a buffer for sprinting console messages if we can't get a page
101 * from system */
102 #define CFS_TRACE_CONSOLE_BUFFER_SIZE 1024
103
104 union cfs_trace_data_union {
105 struct cfs_trace_cpu_data {
106 /*
107 * Even though this structure is meant to be per-CPU, locking
108 * is needed because in some places the data may be accessed
109 * from other CPUs. This lock is directly used in trace_get_tcd
110 * and trace_put_tcd, which are called in libcfs_debug_vmsg2 and
111 * tcd_for_each_type_lock
112 */
113 spinlock_t tcd_lock;
114 unsigned long tcd_lock_flags;
115
116 /*
117 * pages with trace records not yet processed by tracefiled.
118 */
119 struct list_head tcd_pages;
120 /* number of pages on ->tcd_pages */
121 unsigned long tcd_cur_pages;
122
123 /*
124 * pages with trace records already processed by
125 * tracefiled. These pages are kept in memory, so that some
126 * portion of log can be written in the event of LBUG. This
127 * list is maintained in LRU order.
128 *
129 * Pages are moved to ->tcd_daemon_pages by tracefiled()
130 * (put_pages_on_daemon_list()). LRU pages from this list are
131 * discarded when list grows too large.
132 */
133 struct list_head tcd_daemon_pages;
134 /* number of pages on ->tcd_daemon_pages */
135 unsigned long tcd_cur_daemon_pages;
136
137 /*
138 * Maximal number of pages allowed on ->tcd_pages and
139 * ->tcd_daemon_pages each.
140 * Always TCD_MAX_PAGES * tcd_pages_factor / 100 in current
141 * implementation.
142 */
143 unsigned long tcd_max_pages;
144
145 /*
146 * preallocated pages to write trace records into. Pages from
147 * ->tcd_stock_pages are moved to ->tcd_pages by
148 * portals_debug_msg().
149 *
150 * This list is necessary, because on some platforms it's
151 * impossible to perform efficient atomic page allocation in a
152 * non-blockable context.
153 *
154 * Such platforms fill ->tcd_stock_pages "on occasion", when
155 * tracing code is entered in blockable context.
156 *
157 * trace_get_tage_try() tries to get a page from
158 * ->tcd_stock_pages first and resorts to atomic page
159 * allocation only if this queue is empty. ->tcd_stock_pages
160 * is replenished when tracing code is entered in blocking
161 * context (darwin-tracefile.c:trace_get_tcd()). We try to
162 * maintain TCD_STOCK_PAGES (40 by default) pages in this
163 * queue. Atomic allocation is only required if more than
164 * TCD_STOCK_PAGES pagesful are consumed by trace records all
165 * emitted in non-blocking contexts. Which is quite unlikely.
166 */
167 struct list_head tcd_stock_pages;
168 /* number of pages on ->tcd_stock_pages */
169 unsigned long tcd_cur_stock_pages;
170
171 unsigned short tcd_shutting_down;
172 unsigned short tcd_cpu;
173 unsigned short tcd_type;
174 /* The factors to share debug memory. */
175 unsigned short tcd_pages_factor;
176 } tcd;
177 char __pad[L1_CACHE_ALIGN(sizeof(struct cfs_trace_cpu_data))];
178 };
179
180 #define TCD_MAX_TYPES 8
181 extern union cfs_trace_data_union (*cfs_trace_data[TCD_MAX_TYPES])[NR_CPUS];
182
183 #define cfs_tcd_for_each(tcd, i, j) \
184 for (i = 0; cfs_trace_data[i] != NULL; i++) \
185 for (j = 0, ((tcd) = &(*cfs_trace_data[i])[j].tcd); \
186 j < num_possible_cpus(); \
187 j++, (tcd) = &(*cfs_trace_data[i])[j].tcd)
188
189 #define cfs_tcd_for_each_type_lock(tcd, i, cpu) \
190 for (i = 0; cfs_trace_data[i] && \
191 (tcd = &(*cfs_trace_data[i])[cpu].tcd) && \
192 cfs_trace_lock_tcd(tcd, 1); cfs_trace_unlock_tcd(tcd, 1), i++)
193
194 /* XXX nikita: this declaration is internal to tracefile.c and should probably
195 * be moved there */
196 struct page_collection {
197 struct list_head pc_pages;
198 /*
199 * spin-lock protecting ->pc_pages. It is taken by smp_call_function()
200 * call-back functions. XXX nikita: Which is horrible: all processors
201 * receive NMI at the same time only to be serialized by this
202 * lock. Probably ->pc_pages should be replaced with an array of
203 * NR_CPUS elements accessed locklessly.
204 */
205 spinlock_t pc_lock;
206 /*
207 * if this flag is set, collect_pages() will spill both
208 * ->tcd_daemon_pages and ->tcd_pages to the ->pc_pages. Otherwise,
209 * only ->tcd_pages are spilled.
210 */
211 int pc_want_daemon_pages;
212 };
213
214 /* XXX nikita: this declaration is internal to tracefile.c and should probably
215 * be moved there */
216 struct tracefiled_ctl {
217 struct completion tctl_start;
218 struct completion tctl_stop;
219 wait_queue_head_t tctl_waitq;
220 pid_t tctl_pid;
221 atomic_t tctl_shutdown;
222 };
223
224 /*
225 * small data-structure for each page owned by tracefiled.
226 */
227 /* XXX nikita: this declaration is internal to tracefile.c and should probably
228 * be moved there */
229 struct cfs_trace_page {
230 /*
231 * page itself
232 */
233 struct page *page;
234 /*
235 * linkage into one of the lists in trace_data_union or
236 * page_collection
237 */
238 struct list_head linkage;
239 /*
240 * number of bytes used within this page
241 */
242 unsigned int used;
243 /*
244 * cpu that owns this page
245 */
246 unsigned short cpu;
247 /*
248 * type(context) of this page
249 */
250 unsigned short type;
251 };
252
253 void cfs_set_ptldebug_header(struct ptldebug_header *header,
254 struct libcfs_debug_msg_data *m,
255 unsigned long stack);
256 void cfs_print_to_console(struct ptldebug_header *hdr, int mask,
257 const char *buf, int len, const char *file,
258 const char *fn);
259
260 int cfs_trace_lock_tcd(struct cfs_trace_cpu_data *tcd, int walking);
261 void cfs_trace_unlock_tcd(struct cfs_trace_cpu_data *tcd, int walking);
262
263 /**
264 * trace_buf_type_t, trace_buf_idx_get() and trace_console_buffers[][]
265 * are not public libcfs API; they should be defined in
266 * platform-specific tracefile include files
267 * (see, for example, linux-tracefile.h).
268 */
269
270 extern char *cfs_trace_console_buffers[NR_CPUS][CFS_TCD_TYPE_MAX];
271 cfs_trace_buf_type_t cfs_trace_buf_idx_get(void);
272
273 static inline char *
cfs_trace_get_console_buffer(void)274 cfs_trace_get_console_buffer(void)
275 {
276 unsigned int i = get_cpu();
277 unsigned int j = cfs_trace_buf_idx_get();
278
279 return cfs_trace_console_buffers[i][j];
280 }
281
282 static inline void
cfs_trace_put_console_buffer(char * buffer)283 cfs_trace_put_console_buffer(char *buffer)
284 {
285 put_cpu();
286 }
287
288 static inline struct cfs_trace_cpu_data *
cfs_trace_get_tcd(void)289 cfs_trace_get_tcd(void)
290 {
291 struct cfs_trace_cpu_data *tcd =
292 &(*cfs_trace_data[cfs_trace_buf_idx_get()])[get_cpu()].tcd;
293
294 cfs_trace_lock_tcd(tcd, 0);
295
296 return tcd;
297 }
298
299 static inline void
cfs_trace_put_tcd(struct cfs_trace_cpu_data * tcd)300 cfs_trace_put_tcd (struct cfs_trace_cpu_data *tcd)
301 {
302 cfs_trace_unlock_tcd(tcd, 0);
303
304 put_cpu();
305 }
306
307 int cfs_trace_refill_stock(struct cfs_trace_cpu_data *tcd, gfp_t gfp,
308 struct list_head *stock);
309
310 int cfs_tcd_owns_tage(struct cfs_trace_cpu_data *tcd,
311 struct cfs_trace_page *tage);
312
313 void cfs_trace_assertion_failed(const char *str,
314 struct libcfs_debug_msg_data *m);
315
316 /* ASSERTION that is safe to use within the debug system */
317 #define __LASSERT(cond) \
318 do { \
319 if (unlikely(!(cond))) { \
320 LIBCFS_DEBUG_MSG_DATA_DECL(msgdata, D_EMERG, NULL); \
321 cfs_trace_assertion_failed("ASSERTION("#cond") failed", \
322 &msgdata); \
323 } \
324 } while (0)
325
326 #define __LASSERT_TAGE_INVARIANT(tage) \
327 do { \
328 __LASSERT(tage != NULL); \
329 __LASSERT(tage->page != NULL); \
330 __LASSERT(tage->used <= PAGE_CACHE_SIZE); \
331 __LASSERT(page_count(tage->page) > 0); \
332 } while (0)
333
334 #endif /* LUSTRE_TRACEFILE_PRIVATE */
335
336 #endif /* __LIBCFS_TRACEFILE_H__ */
337