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LU-8560 libcfs: handle PAGE_CACHE_* removal in newer kernels
[fs/lustre-release.git] / libcfs / libcfs / tracefile.h
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, 2014, 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 <libcfs/libcfs.h>
41
42 enum cfs_trace_buf_type {
43         CFS_TCD_TYPE_PROC = 0,
44         CFS_TCD_TYPE_SOFTIRQ,
45         CFS_TCD_TYPE_IRQ,
46         CFS_TCD_TYPE_MAX
47 };
48
49 /* trace file lock routines */
50
51 #define TRACEFILE_NAME_SIZE 1024
52 extern char      cfs_tracefile[TRACEFILE_NAME_SIZE];
53 extern long long cfs_tracefile_size;
54
55 extern char lnet_upcall[1024];
56 /**
57  * The path of debug log dump upcall script.
58  */
59 extern char lnet_debug_log_upcall[1024];
60
61 extern void libcfs_run_debug_log_upcall(char *file);
62
63 int  cfs_tracefile_init_arch(void);
64 void cfs_tracefile_fini_arch(void);
65
66 void cfs_tracefile_read_lock(void);
67 void cfs_tracefile_read_unlock(void);
68 void cfs_tracefile_write_lock(void);
69 void cfs_tracefile_write_unlock(void);
70
71 int cfs_tracefile_dump_all_pages(char *filename);
72 void cfs_trace_debug_print(void);
73 void cfs_trace_flush_pages(void);
74 int cfs_trace_start_thread(void);
75 void cfs_trace_stop_thread(void);
76 int cfs_tracefile_init(int max_pages);
77 void cfs_tracefile_exit(void);
78
79
80
81 int cfs_trace_copyin_string(char *knl_buffer, int knl_buffer_nob,
82                             const char __user *usr_buffer, int usr_buffer_nob);
83 int cfs_trace_copyout_string(char __user *usr_buffer, int usr_buffer_nob,
84                              const char *knl_str, char *append);
85 int cfs_trace_allocate_string_buffer(char **str, int nob);
86 int cfs_trace_dump_debug_buffer_usrstr(void __user *usr_str, int usr_str_nob);
87 int cfs_trace_daemon_command(char *str);
88 int cfs_trace_daemon_command_usrstr(void __user *usr_str, int usr_str_nob);
89 int cfs_trace_set_debug_mb(int mb);
90 int cfs_trace_set_debug_mb_usrstr(void __user *usr_str, int usr_str_nob);
91 int cfs_trace_get_debug_mb(void);
92
93 extern void libcfs_debug_dumplog_internal(void *arg);
94 extern void libcfs_register_panic_notifier(void);
95 extern void libcfs_unregister_panic_notifier(void);
96 extern int  libcfs_panic_in_progress;
97 extern int  cfs_trace_max_debug_mb(void);
98
99 #define TCD_MAX_PAGES (5 << (20 - PAGE_SHIFT))
100 #define TCD_STOCK_PAGES (TCD_MAX_PAGES)
101 #define CFS_TRACEFILE_SIZE (500 << 20)
102
103 #ifdef LUSTRE_TRACEFILE_PRIVATE
104
105 /*
106  * Private declare for tracefile
107  */
108 #define TCD_MAX_PAGES (5 << (20 - PAGE_SHIFT))
109 #define TCD_STOCK_PAGES (TCD_MAX_PAGES)
110
111 #define CFS_TRACEFILE_SIZE (500 << 20)
112
113 /* Size of a buffer for sprinting console messages if we can't get a page
114  * from system */
115 #define CFS_TRACE_CONSOLE_BUFFER_SIZE   1024
116
117 union cfs_trace_data_union {
118         struct cfs_trace_cpu_data {
119                 /*
120                  * Even though this structure is meant to be per-CPU, locking
121                  * is needed because in some places the data may be accessed
122                  * from other CPUs. This lock is directly used in trace_get_tcd
123                  * and trace_put_tcd, which are called in libcfs_debug_vmsg2 and
124                  * tcd_for_each_type_lock
125                  */
126                 spinlock_t              tcd_lock;
127                 unsigned long           tcd_lock_flags;
128
129                 /*
130                  * pages with trace records not yet processed by tracefiled.
131                  */
132                 struct list_head        tcd_pages;
133                 /* number of pages on ->tcd_pages */
134                 unsigned long           tcd_cur_pages;
135
136                 /*
137                  * pages with trace records already processed by
138                  * tracefiled. These pages are kept in memory, so that some
139                  * portion of log can be written in the event of LBUG. This
140                  * list is maintained in LRU order.
141                  *
142                  * Pages are moved to ->tcd_daemon_pages by tracefiled()
143                  * (put_pages_on_daemon_list()). LRU pages from this list are
144                  * discarded when list grows too large.
145                  */
146                 struct list_head        tcd_daemon_pages;
147                 /* number of pages on ->tcd_daemon_pages */
148                 unsigned long           tcd_cur_daemon_pages;
149
150                 /*
151                  * Maximal number of pages allowed on ->tcd_pages and
152                  * ->tcd_daemon_pages each.
153                  * Always TCD_MAX_PAGES * tcd_pages_factor / 100 in current
154                  * implementation.
155                  */
156                 unsigned long           tcd_max_pages;
157
158                 /*
159                  * preallocated pages to write trace records into. Pages from
160                  * ->tcd_stock_pages are moved to ->tcd_pages by
161                  * portals_debug_msg().
162                  *
163                  * This list is necessary, because on some platforms it's
164                  * impossible to perform efficient atomic page allocation in a
165                  * non-blockable context.
166                  *
167                  * Such platforms fill ->tcd_stock_pages "on occasion", when
168                  * tracing code is entered in blockable context.
169                  *
170                  * trace_get_tage_try() tries to get a page from
171                  * ->tcd_stock_pages first and resorts to atomic page
172                  * allocation only if this queue is empty. ->tcd_stock_pages
173                  * is replenished when tracing code is entered in blocking
174                  * context (darwin-tracefile.c:trace_get_tcd()). We try to
175                  * maintain TCD_STOCK_PAGES (40 by default) pages in this
176                  * queue. Atomic allocation is only required if more than
177                  * TCD_STOCK_PAGES pagesful are consumed by trace records all
178                  * emitted in non-blocking contexts. Which is quite unlikely.
179                  */
180                 struct list_head        tcd_stock_pages;
181                 /* number of pages on ->tcd_stock_pages */
182                 unsigned long           tcd_cur_stock_pages;
183
184                 unsigned short          tcd_shutting_down;
185                 unsigned short          tcd_cpu;
186                 unsigned short          tcd_type;
187                 /* The factors to share debug memory. */
188                 unsigned short          tcd_pages_factor;
189         } tcd;
190         char __pad[L1_CACHE_ALIGN(sizeof(struct cfs_trace_cpu_data))];
191 };
192
193 #define TCD_MAX_TYPES      8
194 extern union cfs_trace_data_union (*cfs_trace_data[TCD_MAX_TYPES])[NR_CPUS];
195
196 #define cfs_tcd_for_each(tcd, i, j)                                       \
197     for (i = 0; cfs_trace_data[i] != NULL; i++)                           \
198         for (j = 0, ((tcd) = &(*cfs_trace_data[i])[j].tcd);               \
199              j < num_possible_cpus();                                     \
200              j++, (tcd) = &(*cfs_trace_data[i])[j].tcd)
201
202 #define cfs_tcd_for_each_type_lock(tcd, i, cpu)                           \
203     for (i = 0; cfs_trace_data[i] &&                                      \
204          (tcd = &(*cfs_trace_data[i])[cpu].tcd) &&                        \
205          cfs_trace_lock_tcd(tcd, 1); cfs_trace_unlock_tcd(tcd, 1), i++)
206
207 /* XXX nikita: this declaration is internal to tracefile.c and should probably
208  * be moved there */
209 struct page_collection {
210         struct list_head        pc_pages;
211         /*
212          * if this flag is set, collect_pages() will spill both
213          * ->tcd_daemon_pages and ->tcd_pages to the ->pc_pages. Otherwise,
214          * only ->tcd_pages are spilled.
215          */
216         int                     pc_want_daemon_pages;
217 };
218
219 /* XXX nikita: this declaration is internal to tracefile.c and should probably
220  * be moved there */
221 struct tracefiled_ctl {
222         struct completion       tctl_start;
223         struct completion       tctl_stop;
224         wait_queue_head_t       tctl_waitq;
225         pid_t                   tctl_pid;
226         atomic_t                tctl_shutdown;
227 };
228
229 /*
230  * small data-structure for each page owned by tracefiled.
231  */
232 /* XXX nikita: this declaration is internal to tracefile.c and should probably
233  * be moved there */
234 struct cfs_trace_page {
235         /*
236          * page itself
237          */
238         struct page             *page;
239         /*
240          * linkage into one of the lists in trace_data_union or
241          * page_collection
242          */
243         struct list_head        linkage;
244         /*
245          * number of bytes used within this page
246          */
247         unsigned int            used;
248         /*
249          * cpu that owns this page
250          */
251         unsigned short          cpu;
252         /*
253          * type(context) of this page
254          */
255         unsigned short          type;
256 };
257
258 extern void cfs_set_ptldebug_header(struct ptldebug_header *header,
259                                     struct libcfs_debug_msg_data *m,
260                                     unsigned long stack);
261 extern void cfs_print_to_console(struct ptldebug_header *hdr, int mask,
262                                  const char *buf, int len, const char *file,
263                                  const char *fn);
264
265 extern int cfs_trace_lock_tcd(struct cfs_trace_cpu_data *tcd, int walking);
266 extern void cfs_trace_unlock_tcd(struct cfs_trace_cpu_data *tcd, int walking);
267
268 extern char *cfs_trace_console_buffers[NR_CPUS][CFS_TCD_TYPE_MAX];
269 extern enum cfs_trace_buf_type cfs_trace_buf_idx_get(void);
270
271 static inline char *cfs_trace_get_console_buffer(void)
272 {
273         unsigned int i = get_cpu();
274         unsigned int j = cfs_trace_buf_idx_get();
275
276         return cfs_trace_console_buffers[i][j];
277 }
278
279 static inline struct cfs_trace_cpu_data *cfs_trace_get_tcd(void)
280 {
281         struct cfs_trace_cpu_data *tcd =
282                 &(*cfs_trace_data[cfs_trace_buf_idx_get()])[get_cpu()].tcd;
283
284         cfs_trace_lock_tcd(tcd, 0);
285
286         return tcd;
287 }
288
289 static inline void cfs_trace_put_tcd(struct cfs_trace_cpu_data *tcd)
290 {
291         cfs_trace_unlock_tcd(tcd, 0);
292         put_cpu();
293 }
294
295 int cfs_trace_refill_stock(struct cfs_trace_cpu_data *tcd, gfp_t gfp,
296                                 struct list_head *stock);
297
298
299 int cfs_tcd_owns_tage(struct cfs_trace_cpu_data *tcd,
300                       struct cfs_trace_page *tage);
301
302 extern void cfs_trace_assertion_failed(const char *str,
303                                        struct libcfs_debug_msg_data *m);
304
305 /* ASSERTION that is safe to use within the debug system */
306 #define __LASSERT(cond)                                                 \
307 do {                                                                    \
308         if (unlikely(!(cond))) {                                        \
309                 LIBCFS_DEBUG_MSG_DATA_DECL(msgdata, D_EMERG, NULL);     \
310                 cfs_trace_assertion_failed("ASSERTION("#cond") failed", \
311                                            &msgdata);                   \
312         }                                                               \
313 } while (0)
314
315 #define __LASSERT_TAGE_INVARIANT(tage)                                  \
316 do {                                                                    \
317         __LASSERT(tage != NULL);                                        \
318         __LASSERT(tage->page != NULL);                                  \
319         __LASSERT(tage->used <= PAGE_SIZE);                         \
320         __LASSERT(page_count(tage->page) > 0);                      \
321 } while (0)
322
323 #endif  /* LUSTRE_TRACEFILE_PRIVATE */
324
325 #endif /* __LIBCFS_TRACEFILE_H__ */