drivers/staging/lustre/lnet/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.gnu.org/licenses/gpl-2.0.html
  19  *
  20  * GPL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
  24  * Use is subject to license terms.
  25  *
  26  * Copyright (c) 2012, Intel Corporation.
  27  */
  28 /*
  29  * This file is part of Lustre, http://www.lustre.org/
  30  * Lustre is a trademark of Sun Microsystems, Inc.
  31  */
  32
  33 #ifndef __LIBCFS_TRACEFILE_H__
  34 #define __LIBCFS_TRACEFILE_H__
  35
  36 #include <linux/libcfs/libcfs.h>
  37
  38 enum cfs_trace_buf_type {
  39         CFS_TCD_TYPE_PROC = 0,
  40         CFS_TCD_TYPE_SOFTIRQ,
  41         CFS_TCD_TYPE_IRQ,
  42         CFS_TCD_TYPE_MAX
  43 };
  44
  45 /* trace file lock routines */
  46
  47 #define TRACEFILE_NAME_SIZE 1024
  48 extern char cfs_tracefile[TRACEFILE_NAME_SIZE];
  49 extern long long cfs_tracefile_size;
  50
  51 void libcfs_run_debug_log_upcall(char *file);
  52
  53 int  cfs_tracefile_init_arch(void);
  54 void cfs_tracefile_fini_arch(void);
  55
  56 void cfs_tracefile_read_lock(void);
  57 void cfs_tracefile_read_unlock(void);
  58 void cfs_tracefile_write_lock(void);
  59 void cfs_tracefile_write_unlock(void);
  60
  61 int cfs_tracefile_dump_all_pages(char *filename);
  62 void cfs_trace_debug_print(void);
  63 void cfs_trace_flush_pages(void);
  64 int cfs_trace_start_thread(void);
  65 void cfs_trace_stop_thread(void);
  66 int cfs_tracefile_init(int max_pages);
  67 void cfs_tracefile_exit(void);
  68
  69 int cfs_trace_copyin_string(char *knl_buffer, int knl_buffer_nob,
  70                             const char __user *usr_buffer, int usr_buffer_nob);
  71 int cfs_trace_copyout_string(char __user *usr_buffer, int usr_buffer_nob,
  72                              const char *knl_str, char *append);
  73 int cfs_trace_allocate_string_buffer(char **str, int nob);
  74 int cfs_trace_dump_debug_buffer_usrstr(void __user *usr_str, int usr_str_nob);
  75 int cfs_trace_daemon_command(char *str);
  76 int cfs_trace_daemon_command_usrstr(void __user *usr_str, int usr_str_nob);
  77 int cfs_trace_set_debug_mb(int mb);
  78 int cfs_trace_get_debug_mb(void);
  79
  80 void libcfs_debug_dumplog_internal(void *arg);
  81 void libcfs_register_panic_notifier(void);
  82 void libcfs_unregister_panic_notifier(void);
  83 extern int libcfs_panic_in_progress;
  84 int cfs_trace_max_debug_mb(void);
  85
  86 #define TCD_MAX_PAGES (5 << (20 - PAGE_SHIFT))
  87 #define TCD_STOCK_PAGES (TCD_MAX_PAGES)
  88 #define CFS_TRACEFILE_SIZE (500 << 20)
  89
  90 #ifdef LUSTRE_TRACEFILE_PRIVATE
  91
  92 /*
  93  * Private declare for tracefile
  94  */
  95 #define TCD_MAX_PAGES (5 << (20 - PAGE_SHIFT))
  96 #define TCD_STOCK_PAGES (TCD_MAX_PAGES)
  97
  98 #define CFS_TRACEFILE_SIZE (500 << 20)
  99
 100 /*
 101  * Size of a buffer for sprinting console messages if we can't get a page
 102  * from system
 103  */
 104 #define CFS_TRACE_CONSOLE_BUFFER_SIZE   1024
 105
 106 union cfs_trace_data_union {
 107         struct cfs_trace_cpu_data {
 108                 /*
 109                  * Even though this structure is meant to be per-CPU, locking
 110                  * is needed because in some places the data may be accessed
 111                  * from other CPUs. This lock is directly used in trace_get_tcd
 112                  * and trace_put_tcd, which are called in libcfs_debug_vmsg2 and
 113                  * tcd_for_each_type_lock
 114                  */
 115                 spinlock_t              tcd_lock;
 116                 unsigned long           tcd_lock_flags;
 117
 118                 /*
 119                  * pages with trace records not yet processed by tracefiled.
 120                  */
 121                 struct list_head        tcd_pages;
 122                 /* number of pages on ->tcd_pages */
 123                 unsigned long           tcd_cur_pages;
 124
 125                 /*
 126                  * pages with trace records already processed by
 127                  * tracefiled. These pages are kept in memory, so that some
 128                  * portion of log can be written in the event of LBUG. This
 129                  * list is maintained in LRU order.
 130                  *
 131                  * Pages are moved to ->tcd_daemon_pages by tracefiled()
 132                  * (put_pages_on_daemon_list()). LRU pages from this list are
 133                  * discarded when list grows too large.
 134                  */
 135                 struct list_head        tcd_daemon_pages;
 136                 /* number of pages on ->tcd_daemon_pages */
 137                 unsigned long           tcd_cur_daemon_pages;
 138
 139                 /*
 140                  * Maximal number of pages allowed on ->tcd_pages and
 141                  * ->tcd_daemon_pages each.
 142                  * Always TCD_MAX_PAGES * tcd_pages_factor / 100 in current
 143                  * implementation.
 144                  */
 145                 unsigned long           tcd_max_pages;
 146
 147                 /*
 148                  * preallocated pages to write trace records into. Pages from
 149                  * ->tcd_stock_pages are moved to ->tcd_pages by
 150                  * portals_debug_msg().
 151                  *
 152                  * This list is necessary, because on some platforms it's
 153                  * impossible to perform efficient atomic page allocation in a
 154                  * non-blockable context.
 155                  *
 156                  * Such platforms fill ->tcd_stock_pages "on occasion", when
 157                  * tracing code is entered in blockable context.
 158                  *
 159                  * trace_get_tage_try() tries to get a page from
 160                  * ->tcd_stock_pages first and resorts to atomic page
 161                  * allocation only if this queue is empty. ->tcd_stock_pages
 162                  * is replenished when tracing code is entered in blocking
 163                  * context (darwin-tracefile.c:trace_get_tcd()). We try to
 164                  * maintain TCD_STOCK_PAGES (40 by default) pages in this
 165                  * queue. Atomic allocation is only required if more than
 166                  * TCD_STOCK_PAGES pagesful are consumed by trace records all
 167                  * emitted in non-blocking contexts. Which is quite unlikely.
 168                  */
 169                 struct list_head        tcd_stock_pages;
 170                 /* number of pages on ->tcd_stock_pages */
 171                 unsigned long           tcd_cur_stock_pages;
 172
 173                 unsigned short          tcd_shutting_down;
 174                 unsigned short          tcd_cpu;
 175                 unsigned short          tcd_type;
 176                 /* The factors to share debug memory. */
 177                 unsigned short          tcd_pages_factor;
 178         } tcd;
 179         char __pad[L1_CACHE_ALIGN(sizeof(struct cfs_trace_cpu_data))];
 180 };
 181
 182 #define TCD_MAX_TYPES      8
 183 extern union cfs_trace_data_union (*cfs_trace_data[TCD_MAX_TYPES])[NR_CPUS];
 184
 185 #define cfs_tcd_for_each(tcd, i, j)                                    \
 186         for (i = 0; cfs_trace_data[i]; i++)                             \
 187                 for (j = 0, ((tcd) = &(*cfs_trace_data[i])[j].tcd);     \
 188                      j < num_possible_cpus();                            \
 189                      j++, (tcd) = &(*cfs_trace_data[i])[j].tcd)
 190
 191 #define cfs_tcd_for_each_type_lock(tcd, i, cpu)                    \
 192         for (i = 0; cfs_trace_data[i] &&                                \
 193              (tcd = &(*cfs_trace_data[i])[cpu].tcd) &&                  \
 194              cfs_trace_lock_tcd(tcd, 1); cfs_trace_unlock_tcd(tcd, 1), i++)
 195
 196 void cfs_set_ptldebug_header(struct ptldebug_header *header,
 197                              struct libcfs_debug_msg_data *m,
 198                              unsigned long stack);
 199 void cfs_print_to_console(struct ptldebug_header *hdr, int mask,
 200                           const char *buf, int len, const char *file,
 201                           const char *fn);
 202
 203 int cfs_trace_lock_tcd(struct cfs_trace_cpu_data *tcd, int walking);
 204 void cfs_trace_unlock_tcd(struct cfs_trace_cpu_data *tcd, int walking);
 205
 206 extern char *cfs_trace_console_buffers[NR_CPUS][CFS_TCD_TYPE_MAX];
 207 enum cfs_trace_buf_type cfs_trace_buf_idx_get(void);
 208
 209 static inline char *
 210 cfs_trace_get_console_buffer(void)
 211 {
 212         unsigned int i = get_cpu();
 213         unsigned int j = cfs_trace_buf_idx_get();
 214
 215         return cfs_trace_console_buffers[i][j];
 216 }
 217
 218 static inline struct cfs_trace_cpu_data *
 219 cfs_trace_get_tcd(void)
 220 {
 221         struct cfs_trace_cpu_data *tcd =
 222                 &(*cfs_trace_data[cfs_trace_buf_idx_get()])[get_cpu()].tcd;
 223
 224         cfs_trace_lock_tcd(tcd, 0);
 225
 226         return tcd;
 227 }
 228
 229 static inline void cfs_trace_put_tcd(struct cfs_trace_cpu_data *tcd)
 230 {
 231         cfs_trace_unlock_tcd(tcd, 0);
 232
 233         put_cpu();
 234 }
 235
 236 int cfs_trace_refill_stock(struct cfs_trace_cpu_data *tcd, gfp_t gfp,
 237                            struct list_head *stock);
 238
 239 void cfs_trace_assertion_failed(const char *str,
 240                                 struct libcfs_debug_msg_data *m);
 241
 242 /* ASSERTION that is safe to use within the debug system */
 243 #define __LASSERT(cond)                                          \
 244 do {                                                                \
 245         if (unlikely(!(cond))) {                                        \
 246                 LIBCFS_DEBUG_MSG_DATA_DECL(msgdata, D_EMERG, NULL);     \
 247                 cfs_trace_assertion_failed("ASSERTION("#cond") failed", \
 248                                            &msgdata);              \
 249         }                                                              \
 250 } while (0)
 251
 252 #define __LASSERT_TAGE_INVARIANT(tage)                            \
 253 do {                                                                \
 254         __LASSERT(tage);                                        \
 255         __LASSERT(tage->page);                            \
 256         __LASSERT(tage->used <= PAGE_SIZE);                      \
 257         __LASSERT(page_count(tage->page) > 0);                \
 258 } while (0)
 259
 260 #endif  /* LUSTRE_TRACEFILE_PRIVATE */
 261
 262 #endif /* __LIBCFS_TRACEFILE_H__ */