1 files changed, 42 insertions, 54 deletions

diff --git a/module/zfs/zfs_debug.c b/module/zfs/zfs_debug.c
index d0f411a99..f4b5e6fa1 100644
--- a/module/zfs/zfs_debug.c
+++ b/module/zfs/zfs_debug.c
@@ -24,72 +24,60 @@
 
 #include <sys/zfs_context.h>
 
-list_t zfs_dbgmsgs;
-int zfs_dbgmsg_size;
-kmutex_t zfs_dbgmsgs_lock;
-int zfs_dbgmsg_maxsize = 1<<20; /* 1MB */
+/*
+ * 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.
+ */
+int zfs_recover = 0;
 
-void
-zfs_dbgmsg_init(void)
-{
-	list_create(&zfs_dbgmsgs, sizeof (zfs_dbgmsg_t),
-	    offsetof(zfs_dbgmsg_t, zdm_node));
-	mutex_init(&zfs_dbgmsgs_lock, NULL, MUTEX_DEFAULT, NULL);
-}
 
 void
-zfs_dbgmsg_fini(void)
+zfs_panic_recover(const char *fmt, ...)
 {
-	zfs_dbgmsg_t *zdm;
+	va_list adx;
 
-	while ((zdm = list_remove_head(&zfs_dbgmsgs)) != NULL) {
-		int size = sizeof (zfs_dbgmsg_t) + strlen(zdm->zdm_msg);
-		kmem_free(zdm, size);
-		zfs_dbgmsg_size -= size;
-	}
-	mutex_destroy(&zfs_dbgmsgs_lock);
-	ASSERT3U(zfs_dbgmsg_size, ==, 0);
+	va_start(adx, fmt);
+	vcmn_err(zfs_recover ? CE_WARN : CE_PANIC, fmt, adx);
+	va_end(adx);
 }
 
 /*
- * Print these messages by running:
- * 	echo ::zfs_dbgmsg | mdb -k
- *
- * Monitor these messages by running:
- * 	dtrace -q -n 'zfs-dbgmsg{printf("%s\n", stringof(arg0))}'
+ * 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(const char *fmt, ...)
+zfs_dbgmsg_init(void)
 {
-	int size;
-	va_list adx;
-	zfs_dbgmsg_t *zdm;
-
-	va_start(adx, fmt);
-	size = vsnprintf(NULL, 0, fmt, adx);
-	va_end(adx);
+	if (zfs_flags == 0) {
+#if defined(_KERNEL)
+		zfs_flags = ZFS_DEBUG_DPRINTF;
+		spl_debug_mask |= SD_DPRINTF;
+		spl_debug_subsys |= SS_USER1;
+#else
+		zfs_flags = ~ZFS_DEBUG_DPRINTF;
+#endif /* _KERNEL */
+	}
+}
 
-	/*
-	 * 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->zdm_timestamp = gethrestime_sec();
+void
+zfs_dbgmsg_fini(void)
+{
+	return;
+}
 
-	va_start(adx, fmt);
-	(void) vsnprintf(zdm->zdm_msg, size + 1, fmt, adx);
-	va_end(adx);
 
-	DTRACE_PROBE1(zfs__dbgmsg, char *, zdm->zdm_msg);
+#if defined(_KERNEL)
+module_param(zfs_flags, int, 0644);
+MODULE_PARM_DESC(zfs_flags, "Set additional debugging flags");
 
-	mutex_enter(&zfs_dbgmsgs_lock);
-	list_insert_tail(&zfs_dbgmsgs, zdm);
-	zfs_dbgmsg_size += sizeof (zfs_dbgmsg_t) + size;
-	while (zfs_dbgmsg_size > zfs_dbgmsg_maxsize) {
-		zdm = list_remove_head(&zfs_dbgmsgs);
-		size = sizeof (zfs_dbgmsg_t) + strlen(zdm->zdm_msg);
-		kmem_free(zdm, size);
-		zfs_dbgmsg_size -= size;
-	}
-	mutex_exit(&zfs_dbgmsgs_lock);
-}
+module_param(zfs_recover, int, 0644);
+MODULE_PARM_DESC(zfs_recover, "Set to attempt to recover from fatal errors");
+#endif /* _KERNEL */