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