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