diff options
Diffstat (limited to 'module/zfs/zfs_debug.c')
| -rw-r--r-- | module/zfs/zfs_debug.c | 116 |
1 files changed, 17 insertions, 99 deletions
diff --git a/module/zfs/zfs_debug.c b/module/zfs/zfs_debug.c index e7f266b5f..e1675c818 100644 --- a/module/zfs/zfs_debug.c +++ b/module/zfs/zfs_debug.c @@ -25,99 +25,22 @@ #include <sys/zfs_context.h> -#if !defined(_KERNEL) || !defined(__linux__) list_t zfs_dbgmsgs; int zfs_dbgmsg_size; kmutex_t zfs_dbgmsgs_lock; int zfs_dbgmsg_maxsize = 4<<20; /* 4MB */ -#endif -/* - * Enable various debugging features. - */ -int zfs_flags = 0; - -/* - * zfs_recover can be set to nonzero to attempt to recover from - * otherwise-fatal errors, typically caused by on-disk corruption. When - * set, calls to zfs_panic_recover() will turn into warning messages. - * This should only be used as a last resort, as it typically results - * in leaked space, or worse. - */ -int zfs_recover = B_FALSE; - -/* - * If destroy encounters an EIO while reading metadata (e.g. indirect - * blocks), space referenced by the missing metadata can not be freed. - * Normally this causes the background destroy to become "stalled", as - * it is unable to make forward progress. While in this stalled state, - * all remaining space to free from the error-encountering filesystem is - * "temporarily leaked". Set this flag to cause it to ignore the EIO, - * permanently leak the space from indirect blocks that can not be read, - * and continue to free everything else that it can. - * - * The default, "stalling" behavior is useful if the storage partially - * fails (i.e. some but not all i/os fail), and then later recovers. In - * this case, we will be able to continue pool operations while it is - * partially failed, and when it recovers, we can continue to free the - * space, with no leaks. However, note that this case is actually - * fairly rare. - * - * Typically pools either (a) fail completely (but perhaps temporarily, - * e.g. a top-level vdev going offline), or (b) have localized, - * permanent errors (e.g. disk returns the wrong data due to bit flip or - * firmware bug). In case (a), this setting does not matter because the - * pool will be suspended and the sync thread will not be able to make - * forward progress regardless. In case (b), because the error is - * permanent, the best we can do is leak the minimum amount of space, - * which is what setting this flag will do. Therefore, it is reasonable - * for this flag to normally be set, but we chose the more conservative - * approach of not setting it, so that there is no possibility of - * leaking space in the "partial temporary" failure case. - */ -int zfs_free_leak_on_eio = B_FALSE; - - -void -zfs_panic_recover(const char *fmt, ...) -{ - va_list adx; - - va_start(adx, fmt); - vcmn_err(zfs_recover ? CE_WARN : CE_PANIC, fmt, adx); - va_end(adx); -} - -/* - * Debug logging is enabled by default for production kernel builds. - * The overhead for this is negligible and the logs can be valuable when - * debugging. For non-production user space builds all debugging except - * logging is enabled since performance is no longer a concern. - */ void zfs_dbgmsg_init(void) { -#if !defined(_KERNEL) || !defined(__linux__) list_create(&zfs_dbgmsgs, sizeof (zfs_dbgmsg_t), offsetof(zfs_dbgmsg_t, zdm_node)); mutex_init(&zfs_dbgmsgs_lock, NULL, MUTEX_DEFAULT, NULL); -#endif - - if (zfs_flags == 0) { -#if defined(_KERNEL) - zfs_flags = ZFS_DEBUG_DPRINTF; - spl_debug_set_mask(spl_debug_get_mask() | SD_DPRINTF); - spl_debug_set_subsys(spl_debug_get_subsys() | SS_USER1); -#else - zfs_flags = ~ZFS_DEBUG_DPRINTF; -#endif /* _KERNEL */ - } } void zfs_dbgmsg_fini(void) { -#if !defined(_KERNEL) || !defined(__linux__) zfs_dbgmsg_t *zdm; while ((zdm = list_remove_head(&zfs_dbgmsgs)) != NULL) { @@ -127,25 +50,24 @@ zfs_dbgmsg_fini(void) } mutex_destroy(&zfs_dbgmsgs_lock); ASSERT0(zfs_dbgmsg_size); -#endif } -#if !defined(_KERNEL) || !defined(__linux__) /* - * Print these messages by running: - * echo ::zfs_dbgmsg | mdb -k + * To get this data enable the zfs__dbgmsg tracepoint as shown: * - * Monitor these messages by running: - * dtrace -qn 'zfs-dbgmsg{printf("%s\n", stringof(arg0))}' + * # Enable zfs__dbgmsg tracepoint, clear the tracepoint ring buffer + * $ echo 1 > /sys/kernel/debug/tracing/events/zfs/enable + * $ echo 0 > /sys/kernel/debug/tracing/trace * - * When used with libzpool, monitor with: - * dtrace -qn 'zfs$pid::zfs_dbgmsg:probe1{printf("%s\n", copyinstr(arg1))}' + * # Dump the ring buffer. + * $ cat /sys/kernel/debug/tracing/trace */ void zfs_dbgmsg(const char *fmt, ...) { int size; va_list adx; + char *nl; zfs_dbgmsg_t *zdm; va_start(adx, fmt); @@ -156,13 +78,20 @@ zfs_dbgmsg(const char *fmt, ...) * There is one byte of string in sizeof (zfs_dbgmsg_t), used * for the terminating null. */ - zdm = kmem_alloc(sizeof (zfs_dbgmsg_t) + size, KM_SLEEP); + zdm = kmem_alloc(sizeof (zfs_dbgmsg_t) + size, KM_PUSHPAGE); zdm->zdm_timestamp = gethrestime_sec(); va_start(adx, fmt); (void) vsnprintf(zdm->zdm_msg, size + 1, fmt, adx); va_end(adx); + /* + * Get rid of trailing newline. + */ + nl = strrchr(zdm->zdm_msg, '\n'); + if (nl != NULL) + *nl = '\0'; + DTRACE_PROBE1(zfs__dbgmsg, char *, zdm->zdm_msg); mutex_enter(&zfs_dbgmsgs_lock); @@ -180,6 +109,7 @@ zfs_dbgmsg(const char *fmt, ...) void zfs_dbgmsg_print(const char *tag) { +#if !defined(_KERNEL) zfs_dbgmsg_t *zdm; (void) printf("ZFS_DBGMSG(%s):\n", tag); @@ -188,17 +118,5 @@ zfs_dbgmsg_print(const char *tag) zdm = list_next(&zfs_dbgmsgs, zdm)) (void) printf("%s\n", zdm->zdm_msg); mutex_exit(&zfs_dbgmsgs_lock); +#endif /* !_KERNEL */ } -#endif - -#if defined(_KERNEL) -module_param(zfs_flags, int, 0644); -MODULE_PARM_DESC(zfs_flags, "Set additional debugging flags"); - -module_param(zfs_recover, int, 0644); -MODULE_PARM_DESC(zfs_recover, "Set to attempt to recover from fatal errors"); - -module_param(zfs_free_leak_on_eio, int, 0644); -MODULE_PARM_DESC(zfs_free_leak_on_eio, - "Set to ignore IO errors during free and permanently leak the space"); -#endif /* _KERNEL */ |