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 #elif defined(__WINNT__)
  46 #include "winnt/winnt-tracefile.h"
  47 #else
  48 #error Unsupported operating system.
  49 #endif
  50 #else
  51 #include "posix/posix-tracefile.h"
  52 #endif
  53 /* trace file lock routines */
  54
  55 #define TRACEFILE_NAME_SIZE 1024
  56 extern char      cfs_tracefile[TRACEFILE_NAME_SIZE];
  57 extern long long cfs_tracefile_size;
  58
  59 extern void libcfs_run_debug_log_upcall(char *file);
  60
  61 int  cfs_tracefile_init_arch(void);
  62 void cfs_tracefile_fini_arch(void);
  63
  64 void cfs_tracefile_read_lock(void);
  65 void cfs_tracefile_read_unlock(void);
  66 void cfs_tracefile_write_lock(void);
  67 void cfs_tracefile_write_unlock(void);
  68
  69 int cfs_tracefile_dump_all_pages(char *filename);
  70 void cfs_trace_debug_print(void);
  71 void cfs_trace_flush_pages(void);
  72 int cfs_trace_start_thread(void);
  73 void cfs_trace_stop_thread(void);
  74 int cfs_tracefile_init(int max_pages);
  75 void cfs_tracefile_exit(void);
  76
  77
  78
  79 int cfs_trace_copyin_string(char *knl_buffer, int knl_buffer_nob,
  80                             const char *usr_buffer, int usr_buffer_nob);
  81 int cfs_trace_copyout_string(char *usr_buffer, int usr_buffer_nob,
  82                              const char *knl_str, char *append);
  83 int cfs_trace_allocate_string_buffer(char **str, int nob);
  84 void cfs_trace_free_string_buffer(char *str, int nob);
  85 int cfs_trace_dump_debug_buffer_usrstr(void *usr_str, int usr_str_nob);
  86 int cfs_trace_daemon_command(char *str);
  87 int cfs_trace_daemon_command_usrstr(void *usr_str, int usr_str_nob);
  88 int cfs_trace_set_debug_mb(int mb);
  89 int cfs_trace_set_debug_mb_usrstr(void *usr_str, int usr_str_nob);
  90 int cfs_trace_get_debug_mb(void);
  91
  92 extern void libcfs_debug_dumplog_internal(void *arg);
  93 extern void libcfs_register_panic_notifier(void);
  94 extern void libcfs_unregister_panic_notifier(void);
  95 extern int  libcfs_panic_in_progress;
  96 extern int  cfs_trace_max_debug_mb(void);
  97
  98 #define TCD_MAX_PAGES (5 << (20 - PAGE_CACHE_SHIFT))
  99 #define TCD_STOCK_PAGES (TCD_MAX_PAGES)
 100 #define CFS_TRACEFILE_SIZE (500 << 20)
 101
 102 #ifdef LUSTRE_TRACEFILE_PRIVATE
 103
 104 /*
 105  * Private declare for tracefile
 106  */
 107 #define TCD_MAX_PAGES (5 << (20 - PAGE_CACHE_SHIFT))
 108 #define TCD_STOCK_PAGES (TCD_MAX_PAGES)
 109
 110 #define CFS_TRACEFILE_SIZE (500 << 20)
 111
 112 /* Size of a buffer for sprinting console messages if we can't get a page
 113  * from system */
 114 #define CFS_TRACE_CONSOLE_BUFFER_SIZE   1024
 115
 116 union cfs_trace_data_union {
 117         struct cfs_trace_cpu_data {
 118                 /*
 119                  * Even though this structure is meant to be per-CPU, locking
 120                  * is needed because in some places the data may be accessed
 121                  * from other CPUs. This lock is directly used in trace_get_tcd
 122                  * and trace_put_tcd, which are called in libcfs_debug_vmsg2 and
 123                  * tcd_for_each_type_lock
 124                  */
 125                 spinlock_t              tcd_lock;
 126                 unsigned long           tcd_lock_flags;
 127
 128                 /*
 129                  * pages with trace records not yet processed by tracefiled.
 130                  */
 131                 struct list_head        tcd_pages;
 132                 /* number of pages on ->tcd_pages */
 133                 unsigned long           tcd_cur_pages;
 134
 135                 /*
 136                  * pages with trace records already processed by
 137                  * tracefiled. These pages are kept in memory, so that some
 138                  * portion of log can be written in the event of LBUG. This
 139                  * list is maintained in LRU order.
 140                  *
 141                  * Pages are moved to ->tcd_daemon_pages by tracefiled()
 142                  * (put_pages_on_daemon_list()). LRU pages from this list are
 143                  * discarded when list grows too large.
 144                  */
 145                 struct list_head        tcd_daemon_pages;
 146                 /* number of pages on ->tcd_daemon_pages */
 147                 unsigned long           tcd_cur_daemon_pages;
 148
 149                 /*
 150                  * Maximal number of pages allowed on ->tcd_pages and
 151                  * ->tcd_daemon_pages each.
 152                  * Always TCD_MAX_PAGES * tcd_pages_factor / 100 in current
 153                  * implementation.
 154                  */
 155                 unsigned long           tcd_max_pages;
 156
 157                 /*
 158                  * preallocated pages to write trace records into. Pages from
 159                  * ->tcd_stock_pages are moved to ->tcd_pages by
 160                  * portals_debug_msg().
 161                  *
 162                  * This list is necessary, because on some platforms it's
 163                  * impossible to perform efficient atomic page allocation in a
 164                  * non-blockable context.
 165                  *
 166                  * Such platforms fill ->tcd_stock_pages "on occasion", when
 167                  * tracing code is entered in blockable context.
 168                  *
 169                  * trace_get_tage_try() tries to get a page from
 170                  * ->tcd_stock_pages first and resorts to atomic page
 171                  * allocation only if this queue is empty. ->tcd_stock_pages
 172                  * is replenished when tracing code is entered in blocking
 173                  * context (darwin-tracefile.c:trace_get_tcd()). We try to
 174                  * maintain TCD_STOCK_PAGES (40 by default) pages in this
 175                  * queue. Atomic allocation is only required if more than
 176                  * TCD_STOCK_PAGES pagesful are consumed by trace records all
 177                  * emitted in non-blocking contexts. Which is quite unlikely.
 178                  */
 179                 struct list_head        tcd_stock_pages;
 180                 /* number of pages on ->tcd_stock_pages */
 181                 unsigned long           tcd_cur_stock_pages;
 182
 183                 unsigned short          tcd_shutting_down;
 184                 unsigned short          tcd_cpu;
 185                 unsigned short          tcd_type;
 186                 /* The factors to share debug memory. */
 187                 unsigned short          tcd_pages_factor;
 188         } tcd;
 189         char __pad[L1_CACHE_ALIGN(sizeof(struct cfs_trace_cpu_data))];
 190 };
 191
 192 #define TCD_MAX_TYPES      8
 193 extern union cfs_trace_data_union (*cfs_trace_data[TCD_MAX_TYPES])[NR_CPUS];
 194
 195 #define cfs_tcd_for_each(tcd, i, j)                                       \
 196     for (i = 0; cfs_trace_data[i] != NULL; i++)                           \
 197         for (j = 0, ((tcd) = &(*cfs_trace_data[i])[j].tcd);               \
 198              j < num_possible_cpus();                                     \
 199              j++, (tcd) = &(*cfs_trace_data[i])[j].tcd)
 200
 201 #define cfs_tcd_for_each_type_lock(tcd, i, cpu)                           \
 202     for (i = 0; cfs_trace_data[i] &&                                      \
 203          (tcd = &(*cfs_trace_data[i])[cpu].tcd) &&                        \
 204          cfs_trace_lock_tcd(tcd, 1); cfs_trace_unlock_tcd(tcd, 1), i++)
 205
 206 /* XXX nikita: this declaration is internal to tracefile.c and should probably
 207  * be moved there */
 208 struct page_collection {
 209         struct list_head        pc_pages;
 210         /*
 211          * if this flag is set, collect_pages() will spill both
 212          * ->tcd_daemon_pages and ->tcd_pages to the ->pc_pages. Otherwise,
 213          * only ->tcd_pages are spilled.
 214          */
 215         int                     pc_want_daemon_pages;
 216 };
 217
 218 /* XXX nikita: this declaration is internal to tracefile.c and should probably
 219  * be moved there */
 220 struct tracefiled_ctl {
 221         struct completion       tctl_start;
 222         struct completion       tctl_stop;
 223         wait_queue_head_t       tctl_waitq;
 224         pid_t                   tctl_pid;
 225         atomic_t                tctl_shutdown;
 226 };
 227
 228 /*
 229  * small data-structure for each page owned by tracefiled.
 230  */
 231 /* XXX nikita: this declaration is internal to tracefile.c and should probably
 232  * be moved there */
 233 struct cfs_trace_page {
 234         /*
 235          * page itself
 236          */
 237         struct page             *page;
 238         /*
 239          * linkage into one of the lists in trace_data_union or
 240          * page_collection
 241          */
 242         struct list_head        linkage;
 243         /*
 244          * number of bytes used within this page
 245          */
 246         unsigned int            used;
 247         /*
 248          * cpu that owns this page
 249          */
 250         unsigned short          cpu;
 251         /*
 252          * type(context) of this page
 253          */
 254         unsigned short          type;
 255 };
 256
 257 extern void cfs_set_ptldebug_header(struct ptldebug_header *header,
 258                                     struct libcfs_debug_msg_data *m,
 259                                     unsigned long stack);
 260 extern void cfs_print_to_console(struct ptldebug_header *hdr, int mask,
 261                                  const char *buf, int len, const char *file,
 262                                  const char *fn);
 263
 264 extern int cfs_trace_lock_tcd(struct cfs_trace_cpu_data *tcd, int walking);
 265 extern void cfs_trace_unlock_tcd(struct cfs_trace_cpu_data *tcd, int walking);
 266
 267 /**
 268  * trace_buf_type_t, trace_buf_idx_get() and trace_console_buffers[][]
 269  * are not public libcfs API; they should be defined in
 270  * platform-specific tracefile include files
 271  * (see, for example, linux-tracefile.h).
 272  */
 273
 274 extern char *cfs_trace_console_buffers[NR_CPUS][CFS_TCD_TYPE_MAX];
 275 extern cfs_trace_buf_type_t cfs_trace_buf_idx_get(void);
 276
 277 static inline char *cfs_trace_get_console_buffer(void)
 278 {
 279         unsigned int i = get_cpu();
 280         unsigned int j = cfs_trace_buf_idx_get();
 281
 282         return cfs_trace_console_buffers[i][j];
 283 }
 284
 285 static inline void
 286 cfs_trace_put_console_buffer(char *buffer)
 287 {
 288         put_cpu();
 289 }
 290
 291 static inline struct cfs_trace_cpu_data *cfs_trace_get_tcd(void)
 292 {
 293         struct cfs_trace_cpu_data *tcd =
 294                 &(*cfs_trace_data[cfs_trace_buf_idx_get()])[get_cpu()].tcd;
 295
 296         cfs_trace_lock_tcd(tcd, 0);
 297
 298         return tcd;
 299 }
 300
 301 static inline void cfs_trace_put_tcd(struct cfs_trace_cpu_data *tcd)
 302 {
 303         cfs_trace_unlock_tcd(tcd, 0);
 304         put_cpu();
 305 }
 306
 307 int cfs_trace_refill_stock(struct cfs_trace_cpu_data *tcd, int gfp,
 308                                 struct list_head *stock);
 309
 310
 311 int cfs_tcd_owns_tage(struct cfs_trace_cpu_data *tcd,
 312                       struct cfs_trace_page *tage);
 313
 314 extern void cfs_trace_assertion_failed(const char *str,
 315                                        struct libcfs_debug_msg_data *m);
 316
 317 /* ASSERTION that is safe to use within the debug system */
 318 #define __LASSERT(cond)                                                 \
 319 do {                                                                    \
 320         if (unlikely(!(cond))) {                                        \
 321                 LIBCFS_DEBUG_MSG_DATA_DECL(msgdata, D_EMERG, NULL);     \
 322                 cfs_trace_assertion_failed("ASSERTION("#cond") failed", \
 323                                            &msgdata);                   \
 324         }                                                               \
 325 } while (0)
 326
 327 #define __LASSERT_TAGE_INVARIANT(tage)                                  \
 328 do {                                                                    \
 329         __LASSERT(tage != NULL);                                        \
 330         __LASSERT(tage->page != NULL);                                  \
 331         __LASSERT(tage->used <= PAGE_CACHE_SIZE);                         \
 332         __LASSERT(page_count(tage->page) > 0);                      \
 333 } while (0)
 334
 335 #endif  /* LUSTRE_TRACEFILE_PRIVATE */
 336
 337 #endif /* __LIBCFS_TRACEFILE_H__ */