drivers/staging/lustre/lustre/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 "../../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 extern 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
  69
  70 int cfs_trace_copyin_string(char *knl_buffer, int knl_buffer_nob,
  71                             const char *usr_buffer, int usr_buffer_nob);
  72 int cfs_trace_copyout_string(char *usr_buffer, int usr_buffer_nob,
  73                              const char *knl_str, char *append);
  74 int cfs_trace_allocate_string_buffer(char **str, int nob);
  75 void cfs_trace_free_string_buffer(char *str, int nob);
  76 int cfs_trace_dump_debug_buffer_usrstr(void *usr_str, int usr_str_nob);
  77 int cfs_trace_daemon_command(char *str);
  78 int cfs_trace_daemon_command_usrstr(void *usr_str, int usr_str_nob);
  79 int cfs_trace_set_debug_mb(int mb);
  80 int cfs_trace_set_debug_mb_usrstr(void *usr_str, int usr_str_nob);
  81 int cfs_trace_get_debug_mb(void);
  82
  83 extern void libcfs_debug_dumplog_internal(void *arg);
  84 extern void libcfs_register_panic_notifier(void);
  85 extern void libcfs_unregister_panic_notifier(void);
  86 extern int  libcfs_panic_in_progress;
  87 extern int  cfs_trace_max_debug_mb(void);
  88
  89 #define TCD_MAX_PAGES (5 << (20 - PAGE_CACHE_SHIFT))
  90 #define TCD_STOCK_PAGES (TCD_MAX_PAGES)
  91 #define CFS_TRACEFILE_SIZE (500 << 20)
  92
  93 #ifdef LUSTRE_TRACEFILE_PRIVATE
  94
  95 /*
  96  * Private declare for tracefile
  97  */
  98 #define TCD_MAX_PAGES (5 << (20 - PAGE_CACHE_SHIFT))
  99 #define TCD_STOCK_PAGES (TCD_MAX_PAGES)
 100
 101 #define CFS_TRACEFILE_SIZE (500 << 20)
 102
 103 /* Size of a buffer for sprinting console messages if we can't get a page
 104  * from system */
 105 #define CFS_TRACE_CONSOLE_BUFFER_SIZE   1024
 106
 107 union cfs_trace_data_union {
 108         struct cfs_trace_cpu_data {
 109                 /*
 110                  * Even though this structure is meant to be per-CPU, locking
 111                  * is needed because in some places the data may be accessed
 112                  * from other CPUs. This lock is directly used in trace_get_tcd
 113                  * and trace_put_tcd, which are called in libcfs_debug_vmsg2 and
 114                  * tcd_for_each_type_lock
 115                  */
 116                 spinlock_t              tcd_lock;
 117                 unsigned long      tcd_lock_flags;
 118
 119                 /*
 120                  * pages with trace records not yet processed by tracefiled.
 121                  */
 122                 struct list_head              tcd_pages;
 123                 /* number of pages on ->tcd_pages */
 124                 unsigned long      tcd_cur_pages;
 125
 126                 /*
 127                  * pages with trace records already processed by
 128                  * tracefiled. These pages are kept in memory, so that some
 129                  * portion of log can be written in the event of LBUG. This
 130                  * list is maintained in LRU order.
 131                  *
 132                  * Pages are moved to ->tcd_daemon_pages by tracefiled()
 133                  * (put_pages_on_daemon_list()). LRU pages from this list are
 134                  * discarded when list grows too large.
 135                  */
 136                 struct list_head              tcd_daemon_pages;
 137                 /* number of pages on ->tcd_daemon_pages */
 138                 unsigned long      tcd_cur_daemon_pages;
 139
 140                 /*
 141                  * Maximal number of pages allowed on ->tcd_pages and
 142                  * ->tcd_daemon_pages each.
 143                  * Always TCD_MAX_PAGES * tcd_pages_factor / 100 in current
 144                  * implementation.
 145                  */
 146                 unsigned long      tcd_max_pages;
 147
 148                 /*
 149                  * preallocated pages to write trace records into. Pages from
 150                  * ->tcd_stock_pages are moved to ->tcd_pages by
 151                  * portals_debug_msg().
 152                  *
 153                  * This list is necessary, because on some platforms it's
 154                  * impossible to perform efficient atomic page allocation in a
 155                  * non-blockable context.
 156                  *
 157                  * Such platforms fill ->tcd_stock_pages "on occasion", when
 158                  * tracing code is entered in blockable context.
 159                  *
 160                  * trace_get_tage_try() tries to get a page from
 161                  * ->tcd_stock_pages first and resorts to atomic page
 162                  * allocation only if this queue is empty. ->tcd_stock_pages
 163                  * is replenished when tracing code is entered in blocking
 164                  * context (darwin-tracefile.c:trace_get_tcd()). We try to
 165                  * maintain TCD_STOCK_PAGES (40 by default) pages in this
 166                  * queue. Atomic allocation is only required if more than
 167                  * TCD_STOCK_PAGES pagesful are consumed by trace records all
 168                  * emitted in non-blocking contexts. Which is quite unlikely.
 169                  */
 170                 struct list_head              tcd_stock_pages;
 171                 /* number of pages on ->tcd_stock_pages */
 172                 unsigned long      tcd_cur_stock_pages;
 173
 174                 unsigned short    tcd_shutting_down;
 175                 unsigned short    tcd_cpu;
 176                 unsigned short    tcd_type;
 177                 /* The factors to share debug memory. */
 178                 unsigned short    tcd_pages_factor;
 179         } tcd;
 180         char __pad[L1_CACHE_ALIGN(sizeof(struct cfs_trace_cpu_data))];
 181 };
 182
 183 #define TCD_MAX_TYPES      8
 184 extern union cfs_trace_data_union (*cfs_trace_data[TCD_MAX_TYPES])[NR_CPUS];
 185
 186 #define cfs_tcd_for_each(tcd, i, j)                                    \
 187     for (i = 0; cfs_trace_data[i] != NULL; i++)                    \
 188         for (j = 0, ((tcd) = &(*cfs_trace_data[i])[j].tcd);            \
 189              j < num_possible_cpus();                            \
 190              j++, (tcd) = &(*cfs_trace_data[i])[j].tcd)
 191
 192 #define cfs_tcd_for_each_type_lock(tcd, i, cpu)                    \
 193     for (i = 0; cfs_trace_data[i] &&                                  \
 194          (tcd = &(*cfs_trace_data[i])[cpu].tcd) &&                      \
 195          cfs_trace_lock_tcd(tcd, 1); cfs_trace_unlock_tcd(tcd, 1), i++)
 196
 197 /* XXX nikita: this declaration is internal to tracefile.c and should probably
 198  * be moved there */
 199 struct page_collection {
 200         struct list_head        pc_pages;
 201         /*
 202          * spin-lock protecting ->pc_pages. It is taken by smp_call_function()
 203          * call-back functions. XXX nikita: Which is horrible: all processors
 204          * receive NMI at the same time only to be serialized by this
 205          * lock. Probably ->pc_pages should be replaced with an array of
 206          * NR_CPUS elements accessed locklessly.
 207          */
 208         spinlock_t      pc_lock;
 209         /*
 210          * if this flag is set, collect_pages() will spill both
 211          * ->tcd_daemon_pages and ->tcd_pages to the ->pc_pages. Otherwise,
 212          * only ->tcd_pages are spilled.
 213          */
 214         int             pc_want_daemon_pages;
 215 };
 216
 217 /* XXX nikita: this declaration is internal to tracefile.c and should probably
 218  * be moved there */
 219 struct tracefiled_ctl {
 220         struct completion       tctl_start;
 221         struct completion       tctl_stop;
 222         wait_queue_head_t               tctl_waitq;
 223         pid_t                   tctl_pid;
 224         atomic_t                tctl_shutdown;
 225 };
 226
 227 /*
 228  * small data-structure for each page owned by tracefiled.
 229  */
 230 /* XXX nikita: this declaration is internal to tracefile.c and should probably
 231  * be moved there */
 232 struct cfs_trace_page {
 233         /*
 234          * page itself
 235          */
 236         struct page       *page;
 237         /*
 238          * linkage into one of the lists in trace_data_union or
 239          * page_collection
 240          */
 241         struct list_head           linkage;
 242         /*
 243          * number of bytes used within this page
 244          */
 245         unsigned int     used;
 246         /*
 247          * cpu that owns this page
 248          */
 249         unsigned short       cpu;
 250         /*
 251          * type(context) of this page
 252          */
 253         unsigned short       type;
 254 };
 255
 256 extern void cfs_set_ptldebug_header(struct ptldebug_header *header,
 257                                     struct libcfs_debug_msg_data *m,
 258                                     unsigned long stack);
 259 extern void cfs_print_to_console(struct ptldebug_header *hdr, int mask,
 260                                  const char *buf, int len, const char *file,
 261                                  const char *fn);
 262
 263 extern int cfs_trace_lock_tcd(struct cfs_trace_cpu_data *tcd, int walking);
 264 extern void cfs_trace_unlock_tcd(struct cfs_trace_cpu_data *tcd, int walking);
 265
 266 /**
 267  * trace_buf_type_t, trace_buf_idx_get() and trace_console_buffers[][]
 268  * are not public libcfs API; they should be defined in
 269  * platform-specific tracefile include files
 270  * (see, for example, linux-tracefile.h).
 271  */
 272
 273 extern char *cfs_trace_console_buffers[NR_CPUS][CFS_TCD_TYPE_MAX];
 274 extern cfs_trace_buf_type_t cfs_trace_buf_idx_get(void);
 275
 276 static inline char *
 277 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 *
 292 cfs_trace_get_tcd(void)
 293 {
 294         struct cfs_trace_cpu_data *tcd =
 295                 &(*cfs_trace_data[cfs_trace_buf_idx_get()])[get_cpu()].tcd;
 296
 297         cfs_trace_lock_tcd(tcd, 0);
 298
 299         return tcd;
 300 }
 301
 302 static inline void
 303 cfs_trace_put_tcd (struct cfs_trace_cpu_data *tcd)
 304 {
 305         cfs_trace_unlock_tcd(tcd, 0);
 306
 307         put_cpu();
 308 }
 309
 310 int cfs_trace_refill_stock(struct cfs_trace_cpu_data *tcd, gfp_t gfp,
 311                            struct list_head *stock);
 312
 313
 314 int cfs_tcd_owns_tage(struct cfs_trace_cpu_data *tcd,
 315                       struct cfs_trace_page *tage);
 316
 317 extern void cfs_trace_assertion_failed(const char *str,
 318                                        struct libcfs_debug_msg_data *m);
 319
 320 /* ASSERTION that is safe to use within the debug system */
 321 #define __LASSERT(cond)                                          \
 322 do {                                                                \
 323         if (unlikely(!(cond))) {                                        \
 324                 LIBCFS_DEBUG_MSG_DATA_DECL(msgdata, D_EMERG, NULL);     \
 325                 cfs_trace_assertion_failed("ASSERTION("#cond") failed", \
 326                                            &msgdata);              \
 327         }                                                              \
 328 } while (0)
 329
 330 #define __LASSERT_TAGE_INVARIANT(tage)                            \
 331 do {                                                                \
 332         __LASSERT(tage != NULL);                                        \
 333         __LASSERT(tage->page != NULL);                            \
 334         __LASSERT(tage->used <= PAGE_CACHE_SIZE);                        \
 335         __LASSERT(page_count(tage->page) > 0);                \
 336 } while (0)
 337
 338 #endif  /* LUSTRE_TRACEFILE_PRIVATE */
 339
 340 #endif /* __LIBCFS_TRACEFILE_H__ */