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, 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 #ifdef __KERNEL__
  43 # include "linux/linux-tracefile.h"
  44 #else /* __KERNEL__ */
  45 # include "posix/posix-tracefile.h"
  46 #endif /* !__KERNEL__ */
  47 /* trace file lock routines */
  48
  49 #define TRACEFILE_NAME_SIZE 1024
  50 extern char      cfs_tracefile[TRACEFILE_NAME_SIZE];
  51 extern long long cfs_tracefile_size;
  52
  53 extern void libcfs_run_debug_log_upcall(char *file);
  54
  55 int  cfs_tracefile_init_arch(void);
  56 void cfs_tracefile_fini_arch(void);
  57
  58 void cfs_tracefile_read_lock(void);
  59 void cfs_tracefile_read_unlock(void);
  60 void cfs_tracefile_write_lock(void);
  61 void cfs_tracefile_write_unlock(void);
  62
  63 int cfs_tracefile_dump_all_pages(char *filename);
  64 void cfs_trace_debug_print(void);
  65 void cfs_trace_flush_pages(void);
  66 int cfs_trace_start_thread(void);
  67 void cfs_trace_stop_thread(void);
  68 int cfs_tracefile_init(int max_pages);
  69 void cfs_tracefile_exit(void);
  70
  71
  72
  73 int cfs_trace_copyin_string(char *knl_buffer, int knl_buffer_nob,
  74                             const char *usr_buffer, int usr_buffer_nob);
  75 int cfs_trace_copyout_string(char *usr_buffer, int usr_buffer_nob,
  76                              const char *knl_str, char *append);
  77 int cfs_trace_allocate_string_buffer(char **str, int nob);
  78 void cfs_trace_free_string_buffer(char *str, int nob);
  79 int cfs_trace_dump_debug_buffer_usrstr(void *usr_str, int usr_str_nob);
  80 int cfs_trace_daemon_command(char *str);
  81 int cfs_trace_daemon_command_usrstr(void *usr_str, int usr_str_nob);
  82 int cfs_trace_set_debug_mb(int mb);
  83 int cfs_trace_set_debug_mb_usrstr(void *usr_str, int usr_str_nob);
  84 int cfs_trace_get_debug_mb(void);
  85
  86 extern void libcfs_debug_dumplog_internal(void *arg);
  87 extern void libcfs_register_panic_notifier(void);
  88 extern void libcfs_unregister_panic_notifier(void);
  89 extern int  libcfs_panic_in_progress;
  90 extern int  cfs_trace_max_debug_mb(void);
  91
  92 #define TCD_MAX_PAGES (5 << (20 - PAGE_CACHE_SHIFT))
  93 #define TCD_STOCK_PAGES (TCD_MAX_PAGES)
  94 #define CFS_TRACEFILE_SIZE (500 << 20)
  95
  96 #ifdef LUSTRE_TRACEFILE_PRIVATE
  97
  98 /*
  99  * Private declare for tracefile
 100  */
 101 #define TCD_MAX_PAGES (5 << (20 - PAGE_CACHE_SHIFT))
 102 #define TCD_STOCK_PAGES (TCD_MAX_PAGES)
 103
 104 #define CFS_TRACEFILE_SIZE (500 << 20)
 105
 106 /* Size of a buffer for sprinting console messages if we can't get a page
 107  * from system */
 108 #define CFS_TRACE_CONSOLE_BUFFER_SIZE   1024
 109
 110 union cfs_trace_data_union {
 111         struct cfs_trace_cpu_data {
 112                 /*
 113                  * Even though this structure is meant to be per-CPU, locking
 114                  * is needed because in some places the data may be accessed
 115                  * from other CPUs. This lock is directly used in trace_get_tcd
 116                  * and trace_put_tcd, which are called in libcfs_debug_vmsg2 and
 117                  * tcd_for_each_type_lock
 118                  */
 119                 spinlock_t              tcd_lock;
 120                 unsigned long           tcd_lock_flags;
 121
 122                 /*
 123                  * pages with trace records not yet processed by tracefiled.
 124                  */
 125                 struct list_head        tcd_pages;
 126                 /* number of pages on ->tcd_pages */
 127                 unsigned long           tcd_cur_pages;
 128
 129                 /*
 130                  * pages with trace records already processed by
 131                  * tracefiled. These pages are kept in memory, so that some
 132                  * portion of log can be written in the event of LBUG. This
 133                  * list is maintained in LRU order.
 134                  *
 135                  * Pages are moved to ->tcd_daemon_pages by tracefiled()
 136                  * (put_pages_on_daemon_list()). LRU pages from this list are
 137                  * discarded when list grows too large.
 138                  */
 139                 struct list_head        tcd_daemon_pages;
 140                 /* number of pages on ->tcd_daemon_pages */
 141                 unsigned long           tcd_cur_daemon_pages;
 142
 143                 /*
 144                  * Maximal number of pages allowed on ->tcd_pages and
 145                  * ->tcd_daemon_pages each.
 146                  * Always TCD_MAX_PAGES * tcd_pages_factor / 100 in current
 147                  * implementation.
 148                  */
 149                 unsigned long           tcd_max_pages;
 150
 151                 /*
 152                  * preallocated pages to write trace records into. Pages from
 153                  * ->tcd_stock_pages are moved to ->tcd_pages by
 154                  * portals_debug_msg().
 155                  *
 156                  * This list is necessary, because on some platforms it's
 157                  * impossible to perform efficient atomic page allocation in a
 158                  * non-blockable context.
 159                  *
 160                  * Such platforms fill ->tcd_stock_pages "on occasion", when
 161                  * tracing code is entered in blockable context.
 162                  *
 163                  * trace_get_tage_try() tries to get a page from
 164                  * ->tcd_stock_pages first and resorts to atomic page
 165                  * allocation only if this queue is empty. ->tcd_stock_pages
 166                  * is replenished when tracing code is entered in blocking
 167                  * context (darwin-tracefile.c:trace_get_tcd()). We try to
 168                  * maintain TCD_STOCK_PAGES (40 by default) pages in this
 169                  * queue. Atomic allocation is only required if more than
 170                  * TCD_STOCK_PAGES pagesful are consumed by trace records all
 171                  * emitted in non-blocking contexts. Which is quite unlikely.
 172                  */
 173                 struct list_head        tcd_stock_pages;
 174                 /* number of pages on ->tcd_stock_pages */
 175                 unsigned long           tcd_cur_stock_pages;
 176
 177                 unsigned short          tcd_shutting_down;
 178                 unsigned short          tcd_cpu;
 179                 unsigned short          tcd_type;
 180                 /* The factors to share debug memory. */
 181                 unsigned short          tcd_pages_factor;
 182         } tcd;
 183         char __pad[L1_CACHE_ALIGN(sizeof(struct cfs_trace_cpu_data))];
 184 };
 185
 186 #define TCD_MAX_TYPES      8
 187 extern union cfs_trace_data_union (*cfs_trace_data[TCD_MAX_TYPES])[NR_CPUS];
 188
 189 #define cfs_tcd_for_each(tcd, i, j)                                       \
 190     for (i = 0; cfs_trace_data[i] != NULL; i++)                           \
 191         for (j = 0, ((tcd) = &(*cfs_trace_data[i])[j].tcd);               \
 192              j < num_possible_cpus();                                     \
 193              j++, (tcd) = &(*cfs_trace_data[i])[j].tcd)
 194
 195 #define cfs_tcd_for_each_type_lock(tcd, i, cpu)                           \
 196     for (i = 0; cfs_trace_data[i] &&                                      \
 197          (tcd = &(*cfs_trace_data[i])[cpu].tcd) &&                        \
 198          cfs_trace_lock_tcd(tcd, 1); cfs_trace_unlock_tcd(tcd, 1), i++)
 199
 200 /* XXX nikita: this declaration is internal to tracefile.c and should probably
 201  * be moved there */
 202 struct page_collection {
 203         struct list_head        pc_pages;
 204         /*
 205          * if this flag is set, collect_pages() will spill both
 206          * ->tcd_daemon_pages and ->tcd_pages to the ->pc_pages. Otherwise,
 207          * only ->tcd_pages are spilled.
 208          */
 209         int                     pc_want_daemon_pages;
 210 };
 211
 212 /* XXX nikita: this declaration is internal to tracefile.c and should probably
 213  * be moved there */
 214 struct tracefiled_ctl {
 215         struct completion       tctl_start;
 216         struct completion       tctl_stop;
 217         wait_queue_head_t       tctl_waitq;
 218         pid_t                   tctl_pid;
 219         atomic_t                tctl_shutdown;
 220 };
 221
 222 /*
 223  * small data-structure for each page owned by tracefiled.
 224  */
 225 /* XXX nikita: this declaration is internal to tracefile.c and should probably
 226  * be moved there */
 227 struct cfs_trace_page {
 228         /*
 229          * page itself
 230          */
 231         struct page             *page;
 232         /*
 233          * linkage into one of the lists in trace_data_union or
 234          * page_collection
 235          */
 236         struct list_head        linkage;
 237         /*
 238          * number of bytes used within this page
 239          */
 240         unsigned int            used;
 241         /*
 242          * cpu that owns this page
 243          */
 244         unsigned short          cpu;
 245         /*
 246          * type(context) of this page
 247          */
 248         unsigned short          type;
 249 };
 250
 251 extern void cfs_set_ptldebug_header(struct ptldebug_header *header,
 252                                     struct libcfs_debug_msg_data *m,
 253                                     unsigned long stack);
 254 extern void cfs_print_to_console(struct ptldebug_header *hdr, int mask,
 255                                  const char *buf, int len, const char *file,
 256                                  const char *fn);
 257
 258 extern int cfs_trace_lock_tcd(struct cfs_trace_cpu_data *tcd, int walking);
 259 extern void cfs_trace_unlock_tcd(struct cfs_trace_cpu_data *tcd, int walking);
 260
 261 /**
 262  * trace_buf_type_t, trace_buf_idx_get() and trace_console_buffers[][]
 263  * are not public libcfs API; they should be defined in
 264  * platform-specific tracefile include files
 265  * (see, for example, linux-tracefile.h).
 266  */
 267
 268 extern char *cfs_trace_console_buffers[NR_CPUS][CFS_TCD_TYPE_MAX];
 269 extern cfs_trace_buf_type_t 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 void
 280 cfs_trace_put_console_buffer(char *buffer)
 281 {
 282         put_cpu();
 283 }
 284
 285 static inline struct cfs_trace_cpu_data *cfs_trace_get_tcd(void)
 286 {
 287         struct cfs_trace_cpu_data *tcd =
 288                 &(*cfs_trace_data[cfs_trace_buf_idx_get()])[get_cpu()].tcd;
 289
 290         cfs_trace_lock_tcd(tcd, 0);
 291
 292         return tcd;
 293 }
 294
 295 static inline void cfs_trace_put_tcd(struct cfs_trace_cpu_data *tcd)
 296 {
 297         cfs_trace_unlock_tcd(tcd, 0);
 298         put_cpu();
 299 }
 300
 301 int cfs_trace_refill_stock(struct cfs_trace_cpu_data *tcd, gfp_t gfp,
 302                                 struct list_head *stock);
 303
 304
 305 int cfs_tcd_owns_tage(struct cfs_trace_cpu_data *tcd,
 306                       struct cfs_trace_page *tage);
 307
 308 extern void cfs_trace_assertion_failed(const char *str,
 309                                        struct libcfs_debug_msg_data *m);
 310
 311 /* ASSERTION that is safe to use within the debug system */
 312 #define __LASSERT(cond)                                                 \
 313 do {                                                                    \
 314         if (unlikely(!(cond))) {                                        \
 315                 LIBCFS_DEBUG_MSG_DATA_DECL(msgdata, D_EMERG, NULL);     \
 316                 cfs_trace_assertion_failed("ASSERTION("#cond") failed", \
 317                                            &msgdata);                   \
 318         }                                                               \
 319 } while (0)
 320
 321 #define __LASSERT_TAGE_INVARIANT(tage)                                  \
 322 do {                                                                    \
 323         __LASSERT(tage != NULL);                                        \
 324         __LASSERT(tage->page != NULL);                                  \
 325         __LASSERT(tage->used <= PAGE_CACHE_SIZE);                         \
 326         __LASSERT(page_count(tage->page) > 0);                      \
 327 } while (0)
 328
 329 #endif  /* LUSTRE_TRACEFILE_PRIVATE */
 330
 331 #endif /* __LIBCFS_TRACEFILE_H__ */