libcfs/include/libcfs/libcfs_debug.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, 2017, Intel Corporation.
  27  */
  28 /*
  29  * This file is part of Lustre, http://www.lustre.org/
  30  *
  31  * libcfs/include/libcfs/libcfs_debug.h
  32  *
  33  * Debug messages and assertions
  34  *
  35  */
  36
  37 #ifndef __LIBCFS_DEBUG_H__
  38 #define __LIBCFS_DEBUG_H__
  39
  40 #include <linux/tty.h>
  41 #include <linux/limits.h>
  42 #include <uapi/linux/lnet/libcfs_debug.h>
  43
  44 /*
  45  *  Debugging
  46  */
  47 extern unsigned int libcfs_subsystem_debug;
  48 extern unsigned int libcfs_debug;
  49 extern unsigned int libcfs_printk;
  50 extern unsigned int libcfs_watchdog_ratelimit;
  51 extern unsigned int libcfs_console_ratelimit;
  52 extern unsigned int libcfs_console_max_delay;
  53 extern unsigned int libcfs_console_min_delay;
  54 extern unsigned int libcfs_console_backoff;
  55 extern unsigned int libcfs_debug_binary;
  56 extern char *libcfs_debug_file_path;
  57
  58 struct task_struct;
  59
  60 int libcfs_debug_mask2str(char *str, int size, int mask, int is_subsys);
  61 int libcfs_debug_str2mask(int *mask, const char *str, int is_subsys);
  62 void libcfs_debug_dumpstack(struct task_struct *tsk);
  63
  64 /* Has there been an LBUG? */
  65 extern unsigned int libcfs_catastrophe;
  66 extern unsigned int libcfs_panic_on_lbug;
  67
  68 #ifndef DEBUG_SUBSYSTEM
  69 # define DEBUG_SUBSYSTEM S_UNDEFINED
  70 #endif
  71
  72 #define CDEBUG_DEFAULT_MAX_DELAY (cfs_time_seconds(600))         /* jiffies */
  73 #define CDEBUG_DEFAULT_MIN_DELAY ((cfs_time_seconds(1) + 1) / 2) /* jiffies */
  74 #define CDEBUG_DEFAULT_BACKOFF   2
  75 struct cfs_debug_limit_state {
  76         unsigned long   cdls_next;
  77         unsigned int    cdls_delay;
  78         int             cdls_count;
  79 };
  80
  81 struct libcfs_debug_msg_data {
  82         const char                      *msg_file;
  83         const char                      *msg_fn;
  84         int                              msg_subsys;
  85         int                              msg_line;
  86         int                              msg_mask;
  87         struct cfs_debug_limit_state    *msg_cdls;
  88 };
  89
  90 #define LIBCFS_DEBUG_MSG_DATA_INIT(file, func, line, msgdata, mask, cdls)\
  91 do {                                                                    \
  92         (msgdata)->msg_subsys = DEBUG_SUBSYSTEM;                        \
  93         (msgdata)->msg_file   = (file);                                 \
  94         (msgdata)->msg_fn     = (func);                                 \
  95         (msgdata)->msg_line   = (line);                                 \
  96         (msgdata)->msg_mask   = (mask);                                 \
  97         (msgdata)->msg_cdls   = (cdls);                                 \
  98 } while (0)
  99
 100 #define LIBCFS_DEBUG_MSG_DATA_DECL_LOC(file, func, line, msgdata, mask, cdls)\
 101         static struct libcfs_debug_msg_data msgdata = {                 \
 102                 .msg_subsys = DEBUG_SUBSYSTEM,                          \
 103                 .msg_file   = (file),                                   \
 104                 .msg_fn     = (func),                                   \
 105                 .msg_line   = (line),                                   \
 106                 .msg_cdls   = (cdls) };                                 \
 107         msgdata.msg_mask   = (mask)
 108
 109 #define LIBCFS_DEBUG_MSG_DATA_DECL(msgdata, mask, cdls)                 \
 110         LIBCFS_DEBUG_MSG_DATA_DECL_LOC(__FILE__, __func__, __LINE__,    \
 111                                        msgdata, mask, cdls)
 112
 113 #ifdef CDEBUG_ENABLED
 114
 115 /**
 116  * Filters out logging messages based on mask and subsystem.
 117  */
 118 static inline int cfs_cdebug_show(unsigned int mask, unsigned int subsystem)
 119 {
 120         return mask & D_CANTMASK ||
 121                ((libcfs_debug & mask) && (libcfs_subsystem_debug & subsystem));
 122 }
 123
 124 #  define __CDEBUG_WITH_LOC(file, func, line, mask, cdls, format, ...)  \
 125 do {                                                                    \
 126         static struct libcfs_debug_msg_data msgdata;                    \
 127                                                                         \
 128         if (cfs_cdebug_show(mask, DEBUG_SUBSYSTEM)) {                   \
 129                 LIBCFS_DEBUG_MSG_DATA_INIT(file, func, line,            \
 130                                            &msgdata, mask, cdls);       \
 131                 libcfs_debug_msg(&msgdata, format, ## __VA_ARGS__);     \
 132         }                                                               \
 133 } while (0)
 134
 135 #  define CDEBUG(mask, format, ...)                                     \
 136         __CDEBUG_WITH_LOC(__FILE__, __func__, __LINE__,                 \
 137                           mask, NULL, format, ## __VA_ARGS__)
 138
 139 #  define CDEBUG_LIMIT(mask, format, ...)                               \
 140 do {                                                                    \
 141         static struct cfs_debug_limit_state cdls;                       \
 142                                                                         \
 143         __CDEBUG_WITH_LOC(__FILE__, __func__, __LINE__,                 \
 144                           mask, &cdls, format, ## __VA_ARGS__);         \
 145 } while (0)
 146
 147 # else /* !CDEBUG_ENABLED */
 148 static inline int cfs_cdebug_show(unsigned int mask, unsigned int subsystem)
 149 {
 150         return 0;
 151 }
 152 #  define CDEBUG(mask, format, ...) (void)(0)
 153 #  define CDEBUG_LIMIT(mask, format, ...) (void)(0)
 154 #  warning "CDEBUG IS DISABLED. THIS SHOULD NEVER BE DONE FOR PRODUCTION!"
 155 # endif /* CDEBUG_ENABLED */
 156
 157 /*
 158  * Lustre Error Checksum: calculates checksum
 159  * of Hex number by XORing each bit.
 160  */
 161 #define LERRCHKSUM(hexnum) (((hexnum) & 0xf) ^ ((hexnum) >> 4 & 0xf) ^ \
 162                            ((hexnum) >> 8 & 0xf))
 163
 164 #define CWARN(format, ...)          CDEBUG_LIMIT(D_WARNING, format, ## __VA_ARGS__)
 165 #define CERROR(format, ...)         CDEBUG_LIMIT(D_ERROR, format, ## __VA_ARGS__)
 166 #define CNETERR(format, a...)       CDEBUG_LIMIT(D_NETERROR, format, ## a)
 167 #define CEMERG(format, ...)         CDEBUG_LIMIT(D_EMERG, format, ## __VA_ARGS__)
 168
 169 #define LCONSOLE(mask, format, ...) CDEBUG(D_CONSOLE | (mask), format, ## __VA_ARGS__)
 170 #define LCONSOLE_INFO(format, ...)  CDEBUG_LIMIT(D_CONSOLE, format, ## __VA_ARGS__)
 171 #define LCONSOLE_WARN(format, ...)  CDEBUG_LIMIT(D_CONSOLE | D_WARNING, format, ## __VA_ARGS__)
 172 #define LCONSOLE_ERROR_MSG(errnum, format, ...) CDEBUG_LIMIT(D_CONSOLE | D_ERROR, \
 173                            "%x-%x: " format, errnum, LERRCHKSUM(errnum), ## __VA_ARGS__)
 174 #define LCONSOLE_ERROR(format, ...) LCONSOLE_ERROR_MSG(0x00, format, ## __VA_ARGS__)
 175
 176 #define LCONSOLE_EMERG(format, ...) \
 177         CDEBUG(D_CONSOLE | D_EMERG, format, ## __VA_ARGS__)
 178
 179 int libcfs_debug_msg(struct libcfs_debug_msg_data *msgdata,
 180                      const char *format1, ...)
 181         __printf(2, 3);
 182
 183 /* other external symbols that tracefile provides: */
 184 int cfs_trace_copyout_string(char __user *usr_buffer, int usr_buffer_nob,
 185                              const char *knl_buffer, char *append);
 186
 187 #define LIBCFS_DEBUG_FILE_PATH_DEFAULT "/tmp/lustre-log"
 188
 189 #if defined(CDEBUG_ENTRY_EXIT)
 190
 191 static inline long libcfs_log_return(struct libcfs_debug_msg_data *msgdata, long rc)
 192 {
 193         libcfs_debug_msg(msgdata, "Process leaving (rc=%lu : %ld : %lx)\n",
 194                          rc, rc, rc);
 195         return rc;
 196 }
 197
 198 static inline void libcfs_log_goto(struct libcfs_debug_msg_data *msgdata,
 199                                    const char *label, long rc)
 200 {
 201         libcfs_debug_msg(msgdata,
 202                          "Process leaving via %s (rc=%lu : %ld : %#lx)\n",
 203                          label, rc, rc, rc);
 204 }
 205
 206 # define GOTO(label, rc)                                                      \
 207 do {                                                                          \
 208         if (cfs_cdebug_show(D_TRACE, DEBUG_SUBSYSTEM)) {                      \
 209                 LIBCFS_DEBUG_MSG_DATA_DECL(_goto_data, D_TRACE, NULL);        \
 210                 libcfs_log_goto(&_goto_data, #label, (long)(rc));             \
 211         } else {                                                              \
 212                 (void)(rc);                                                   \
 213         }                                                                     \
 214                                                                               \
 215         goto label;                                                           \
 216 } while (0)
 217
 218 # if BITS_PER_LONG > 32
 219 #  define RETURN(rc)                                                          \
 220 do {                                                                          \
 221         if (cfs_cdebug_show(D_TRACE, DEBUG_SUBSYSTEM)) {                      \
 222                 LIBCFS_DEBUG_MSG_DATA_DECL(msgdata, D_TRACE, NULL);           \
 223                 return (typeof(rc))libcfs_log_return(&msgdata,                \
 224                                                      (long)(rc));             \
 225         }                                                                     \
 226                                                                               \
 227         return rc;                                                            \
 228 } while (0)
 229 # else /* BITS_PER_LONG == 32 */
 230 /* We need an on-stack variable, because we cannot case a 32-bit pointer
 231  * directly to (long long) without generating a complier warning/error, yet
 232  * casting directly to (long) will truncate 64-bit return values. The log
 233  * values will print as 32-bit values, but they always have been. LU-1436
 234  */
 235 #  define RETURN(rc)                                                          \
 236 do {                                                                          \
 237         if (cfs_cdebug_show(D_TRACE, DEBUG_SUBSYSTEM)) {                      \
 238                 typeof(rc) __rc = (rc);                                       \
 239                 LIBCFS_DEBUG_MSG_DATA_DECL(msgdata, D_TRACE, NULL);           \
 240                 libcfs_log_return(&msgdata, (long)__rc);                      \
 241                 return __rc;                                                  \
 242         }                                                                     \
 243                                                                               \
 244         return rc;                                                            \
 245 } while (0)
 246
 247 # endif /* BITS_PER_LONG > 32 */
 248
 249 # define ENTRY  CDEBUG(D_TRACE, "Process entered\n")
 250 # define EXIT   CDEBUG(D_TRACE, "Process leaving\n")
 251
 252 #else /* !CDEBUG_ENTRY_EXIT */
 253
 254 # define GOTO(label, rc)                                                \
 255         do {                                                            \
 256                 ((void)(rc));                                           \
 257                 goto label;                                             \
 258         } while (0)
 259
 260 # define RETURN(rc) return (rc)
 261 # define ENTRY  do { } while (0)
 262 # define EXIT   do { } while (0)
 263
 264 #endif /* CDEBUG_ENTRY_EXIT */
 265
 266 #define RETURN_EXIT                                                     \
 267 do {                                                                    \
 268         EXIT;                                                           \
 269         return;                                                         \
 270 } while (0)
 271
 272 static inline void cfs_tty_write_msg(const char *msg)
 273 {
 274         struct tty_struct *tty;
 275
 276         tty = get_current_tty();
 277         if (!tty)
 278                 return;
 279         mutex_lock(&tty->atomic_write_lock);
 280         tty_lock(tty);
 281         if (tty->ops->write && tty->count > 0)
 282                 tty->ops->write(tty, msg, strlen(msg));
 283         tty_unlock(tty);
 284         mutex_unlock(&tty->atomic_write_lock);
 285         wake_up_interruptible_poll(&tty->write_wait, POLL_OUT);
 286         tty_kref_put(tty);
 287 }
 288
 289 #endif  /* __LIBCFS_DEBUG_H__ */