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 #if defined(__linux__)
  44 #include "linux/linux-tracefile.h"
  45 #else
  46 #error Unsupported operating system.
  47 #endif
  48 #else
  49 #include "posix/posix-tracefile.h"
  50 #endif
  51 /* trace file lock routines */
  52
  53 #define TRACEFILE_NAME_SIZE 1024
  54 extern char      cfs_tracefile[TRACEFILE_NAME_SIZE];
  55 extern long long cfs_tracefile_size;
  56
  57 extern void libcfs_run_debug_log_upcall(char *file);
  58
  59 int  cfs_tracefile_init_arch(void);
  60 void cfs_tracefile_fini_arch(void);
  61
  62 void cfs_tracefile_read_lock(void);
  63 void cfs_tracefile_read_unlock(void);
  64 void cfs_tracefile_write_lock(void);
  65 void cfs_tracefile_write_unlock(void);
  66
  67 int cfs_tracefile_dump_all_pages(char *filename);
  68 void cfs_trace_debug_print(void);
  69 void cfs_trace_flush_pages(void);
  70 int cfs_trace_start_thread(void);
  71 void cfs_trace_stop_thread(void);
  72 int cfs_tracefile_init(int max_pages);
  73 void cfs_tracefile_exit(void);
  74
  75
  76
  77 int cfs_trace_copyin_string(char *knl_buffer, int knl_buffer_nob,
  78                             const char *usr_buffer, int usr_buffer_nob);
  79 int cfs_trace_copyout_string(char *usr_buffer, int usr_buffer_nob,
  80                              const char *knl_str, char *append);
  81 int cfs_trace_allocate_string_buffer(char **str, int nob);
  82 void cfs_trace_free_string_buffer(char *str, int nob);
  83 int cfs_trace_dump_debug_buffer_usrstr(void *usr_str, int usr_str_nob);
  84 int cfs_trace_daemon_command(char *str);
  85 int cfs_trace_daemon_command_usrstr(void *usr_str, int usr_str_nob);
  86 int cfs_trace_set_debug_mb(int mb);
  87 int cfs_trace_set_debug_mb_usrstr(void *usr_str, int usr_str_nob);
  88 int cfs_trace_get_debug_mb(void);
  89
  90 extern void libcfs_debug_dumplog_internal(void *arg);
  91 extern void libcfs_register_panic_notifier(void);
  92 extern void libcfs_unregister_panic_notifier(void);
  93 extern int  libcfs_panic_in_progress;
  94 extern int  cfs_trace_max_debug_mb(void);
  95
  96 #define TCD_MAX_PAGES (5 << (20 - PAGE_CACHE_SHIFT))
  97 #define TCD_STOCK_PAGES (TCD_MAX_PAGES)
  98 #define CFS_TRACEFILE_SIZE (500 << 20)
  99
 100 #ifdef LUSTRE_TRACEFILE_PRIVATE
 101
 102 /*
 103  * Private declare for tracefile
 104  */
 105 #define TCD_MAX_PAGES (5 << (20 - PAGE_CACHE_SHIFT))
 106 #define TCD_STOCK_PAGES (TCD_MAX_PAGES)
 107
 108 #define CFS_TRACEFILE_SIZE (500 << 20)
 109
 110 /* Size of a buffer for sprinting console messages if we can't get a page
 111  * from system */
 112 #define CFS_TRACE_CONSOLE_BUFFER_SIZE   1024
 113
 114 union cfs_trace_data_union {
 115         struct cfs_trace_cpu_data {
 116                 /*
 117                  * Even though this structure is meant to be per-CPU, locking
 118                  * is needed because in some places the data may be accessed
 119                  * from other CPUs. This lock is directly used in trace_get_tcd
 120                  * and trace_put_tcd, which are called in libcfs_debug_vmsg2 and
 121                  * tcd_for_each_type_lock
 122                  */
 123                 spinlock_t              tcd_lock;
 124                 unsigned long           tcd_lock_flags;
 125
 126                 /*
 127                  * pages with trace records not yet processed by tracefiled.
 128                  */
 129                 struct list_head        tcd_pages;
 130                 /* number of pages on ->tcd_pages */
 131                 unsigned long           tcd_cur_pages;
 132
 133                 /*
 134                  * pages with trace records already processed by
 135                  * tracefiled. These pages are kept in memory, so that some
 136                  * portion of log can be written in the event of LBUG. This
 137                  * list is maintained in LRU order.
 138                  *
 139                  * Pages are moved to ->tcd_daemon_pages by tracefiled()
 140                  * (put_pages_on_daemon_list()). LRU pages from this list are
 141                  * discarded when list grows too large.
 142                  */
 143                 struct list_head        tcd_daemon_pages;
 144                 /* number of pages on ->tcd_daemon_pages */
 145                 unsigned long           tcd_cur_daemon_pages;
 146
 147                 /*
 148                  * Maximal number of pages allowed on ->tcd_pages and
 149                  * ->tcd_daemon_pages each.
 150                  * Always TCD_MAX_PAGES * tcd_pages_factor / 100 in current
 151                  * implementation.
 152                  */
 153                 unsigned long           tcd_max_pages;
 154
 155                 /*
 156                  * preallocated pages to write trace records into. Pages from
 157                  * ->tcd_stock_pages are moved to ->tcd_pages by
 158                  * portals_debug_msg().
 159                  *
 160                  * This list is necessary, because on some platforms it's
 161                  * impossible to perform efficient atomic page allocation in a
 162                  * non-blockable context.
 163                  *
 164                  * Such platforms fill ->tcd_stock_pages "on occasion", when
 165                  * tracing code is entered in blockable context.
 166                  *
 167                  * trace_get_tage_try() tries to get a page from
 168                  * ->tcd_stock_pages first and resorts to atomic page
 169                  * allocation only if this queue is empty. ->tcd_stock_pages
 170                  * is replenished when tracing code is entered in blocking
 171                  * context (darwin-tracefile.c:trace_get_tcd()). We try to
 172                  * maintain TCD_STOCK_PAGES (40 by default) pages in this
 173                  * queue. Atomic allocation is only required if more than
 174                  * TCD_STOCK_PAGES pagesful are consumed by trace records all
 175                  * emitted in non-blocking contexts. Which is quite unlikely.
 176                  */
 177                 struct list_head        tcd_stock_pages;
 178                 /* number of pages on ->tcd_stock_pages */
 179                 unsigned long           tcd_cur_stock_pages;
 180
 181                 unsigned short          tcd_shutting_down;
 182                 unsigned short          tcd_cpu;
 183                 unsigned short          tcd_type;
 184                 /* The factors to share debug memory. */
 185                 unsigned short          tcd_pages_factor;
 186         } tcd;
 187         char __pad[L1_CACHE_ALIGN(sizeof(struct cfs_trace_cpu_data))];
 188 };
 189
 190 #define TCD_MAX_TYPES      8
 191 extern union cfs_trace_data_union (*cfs_trace_data[TCD_MAX_TYPES])[NR_CPUS];
 192
 193 #define cfs_tcd_for_each(tcd, i, j)                                       \
 194     for (i = 0; cfs_trace_data[i] != NULL; i++)                           \
 195         for (j = 0, ((tcd) = &(*cfs_trace_data[i])[j].tcd);               \
 196              j < num_possible_cpus();                                     \
 197              j++, (tcd) = &(*cfs_trace_data[i])[j].tcd)
 198
 199 #define cfs_tcd_for_each_type_lock(tcd, i, cpu)                           \
 200     for (i = 0; cfs_trace_data[i] &&                                      \
 201          (tcd = &(*cfs_trace_data[i])[cpu].tcd) &&                        \
 202          cfs_trace_lock_tcd(tcd, 1); cfs_trace_unlock_tcd(tcd, 1), i++)
 203
 204 /* XXX nikita: this declaration is internal to tracefile.c and should probably
 205  * be moved there */
 206 struct page_collection {
 207         struct list_head        pc_pages;
 208         /*
 209          * if this flag is set, collect_pages() will spill both
 210          * ->tcd_daemon_pages and ->tcd_pages to the ->pc_pages. Otherwise,
 211          * only ->tcd_pages are spilled.
 212          */
 213         int                     pc_want_daemon_pages;
 214 };
 215
 216 /* XXX nikita: this declaration is internal to tracefile.c and should probably
 217  * be moved there */
 218 struct tracefiled_ctl {
 219         struct completion       tctl_start;
 220         struct completion       tctl_stop;
 221         wait_queue_head_t       tctl_waitq;
 222         pid_t                   tctl_pid;
 223         atomic_t                tctl_shutdown;
 224 };
 225
 226 /*
 227  * small data-structure for each page owned by tracefiled.
 228  */
 229 /* XXX nikita: this declaration is internal to tracefile.c and should probably
 230  * be moved there */
 231 struct cfs_trace_page {
 232         /*
 233          * page itself
 234          */
 235         struct page             *page;
 236         /*
 237          * linkage into one of the lists in trace_data_union or
 238          * page_collection
 239          */
 240         struct list_head        linkage;
 241         /*
 242          * number of bytes used within this page
 243          */
 244         unsigned int            used;
 245         /*
 246          * cpu that owns this page
 247          */
 248         unsigned short          cpu;
 249         /*
 250          * type(context) of this page
 251          */
 252         unsigned short          type;
 253 };
 254
 255 extern void cfs_set_ptldebug_header(struct ptldebug_header *header,
 256                                     struct libcfs_debug_msg_data *m,
 257                                     unsigned long stack);
 258 extern void cfs_print_to_console(struct ptldebug_header *hdr, int mask,
 259                                  const char *buf, int len, const char *file,
 260                                  const char *fn);
 261
 262 extern int cfs_trace_lock_tcd(struct cfs_trace_cpu_data *tcd, int walking);
 263 extern void cfs_trace_unlock_tcd(struct cfs_trace_cpu_data *tcd, int walking);
 264
 265 /**
 266  * trace_buf_type_t, trace_buf_idx_get() and trace_console_buffers[][]
 267  * are not public libcfs API; they should be defined in
 268  * platform-specific tracefile include files
 269  * (see, for example, linux-tracefile.h).
 270  */
 271
 272 extern char *cfs_trace_console_buffers[NR_CPUS][CFS_TCD_TYPE_MAX];
 273 extern cfs_trace_buf_type_t cfs_trace_buf_idx_get(void);
 274
 275 static inline char *cfs_trace_get_console_buffer(void)
 276 {
 277         unsigned int i = get_cpu();
 278         unsigned int j = cfs_trace_buf_idx_get();
 279
 280         return cfs_trace_console_buffers[i][j];
 281 }
 282
 283 static inline void
 284 cfs_trace_put_console_buffer(char *buffer)
 285 {
 286         put_cpu();
 287 }
 288
 289 static inline struct cfs_trace_cpu_data *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 {
 301         cfs_trace_unlock_tcd(tcd, 0);
 302         put_cpu();
 303 }
 304
 305 int cfs_trace_refill_stock(struct cfs_trace_cpu_data *tcd, int gfp,
 306                                 struct list_head *stock);
 307
 308
 309 int cfs_tcd_owns_tage(struct cfs_trace_cpu_data *tcd,
 310                       struct cfs_trace_page *tage);
 311
 312 extern void cfs_trace_assertion_failed(const char *str,
 313                                        struct libcfs_debug_msg_data *m);
 314
 315 /* ASSERTION that is safe to use within the debug system */
 316 #define __LASSERT(cond)                                                 \
 317 do {                                                                    \
 318         if (unlikely(!(cond))) {                                        \
 319                 LIBCFS_DEBUG_MSG_DATA_DECL(msgdata, D_EMERG, NULL);     \
 320                 cfs_trace_assertion_failed("ASSERTION("#cond") failed", \
 321                                            &msgdata);                   \
 322         }                                                               \
 323 } while (0)
 324
 325 #define __LASSERT_TAGE_INVARIANT(tage)                                  \
 326 do {                                                                    \
 327         __LASSERT(tage != NULL);                                        \
 328         __LASSERT(tage->page != NULL);                                  \
 329         __LASSERT(tage->used <= PAGE_CACHE_SIZE);                         \
 330         __LASSERT(page_count(tage->page) > 0);                      \
 331 } while (0)
 332
 333 #endif  /* LUSTRE_TRACEFILE_PRIVATE */
 334
 335 #endif /* __LIBCFS_TRACEFILE_H__ */