diff options
Diffstat (limited to 'sys/contrib/openzfs/module/os/linux/zfs/zfs_debug.c')
| -rw-r--r-- | sys/contrib/openzfs/module/os/linux/zfs/zfs_debug.c | 219 |
1 files changed, 219 insertions, 0 deletions
diff --git a/sys/contrib/openzfs/module/os/linux/zfs/zfs_debug.c b/sys/contrib/openzfs/module/os/linux/zfs/zfs_debug.c new file mode 100644 index 000000000000..879748f6950d --- /dev/null +++ b/sys/contrib/openzfs/module/os/linux/zfs/zfs_debug.c @@ -0,0 +1,219 @@ +// SPDX-License-Identifier: CDDL-1.0 +/* + * CDDL HEADER START + * + * The contents of this file are subject to the terms of the + * Common Development and Distribution License (the "License"). + * You may not use this file except in compliance with the License. + * + * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE + * or https://opensource.org/licenses/CDDL-1.0. + * See the License for the specific language governing permissions + * and limitations under the License. + * + * When distributing Covered Code, include this CDDL HEADER in each + * file and include the License file at usr/src/OPENSOLARIS.LICENSE. + * If applicable, add the following below this CDDL HEADER, with the + * fields enclosed by brackets "[]" replaced with your own identifying + * information: Portions Copyright [yyyy] [name of copyright owner] + * + * CDDL HEADER END + */ +/* + * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved. + * Copyright (c) 2012, 2014 by Delphix. All rights reserved. + */ + +#include <sys/zfs_context.h> +#include <sys/trace_zfs.h> + +typedef struct zfs_dbgmsg { + procfs_list_node_t zdm_node; + uint64_t zdm_timestamp; + uint_t zdm_size; + char zdm_msg[]; /* variable length allocation */ +} zfs_dbgmsg_t; + +static procfs_list_t zfs_dbgmsgs; +static uint_t zfs_dbgmsg_size = 0; +static uint_t zfs_dbgmsg_maxsize = 4<<20; /* 4MB */ + +/* + * Internal ZFS debug messages are enabled by default. + * + * # Print debug messages + * cat /proc/spl/kstat/zfs/dbgmsg + * + * # Disable the kernel debug message log. + * echo 0 > /sys/module/zfs/parameters/zfs_dbgmsg_enable + * + * # Clear the kernel debug message log. + * echo 0 >/proc/spl/kstat/zfs/dbgmsg + */ +int zfs_dbgmsg_enable = B_TRUE; + +static int +zfs_dbgmsg_show_header(struct seq_file *f) +{ + seq_printf(f, "%-12s %-8s\n", "timestamp", "message"); + return (0); +} + +static int +zfs_dbgmsg_show(struct seq_file *f, void *p) +{ + zfs_dbgmsg_t *zdm = (zfs_dbgmsg_t *)p; + seq_printf(f, "%-12llu %-s\n", + (u_longlong_t)zdm->zdm_timestamp, zdm->zdm_msg); + return (0); +} + +static void +zfs_dbgmsg_purge(uint_t max_size) +{ + while (zfs_dbgmsg_size > max_size) { + zfs_dbgmsg_t *zdm = list_remove_head(&zfs_dbgmsgs.pl_list); + if (zdm == NULL) + return; + + uint_t size = zdm->zdm_size; + kmem_free(zdm, size); + zfs_dbgmsg_size -= size; + } +} + +static int +zfs_dbgmsg_clear(procfs_list_t *procfs_list) +{ + (void) procfs_list; + mutex_enter(&zfs_dbgmsgs.pl_lock); + zfs_dbgmsg_purge(0); + mutex_exit(&zfs_dbgmsgs.pl_lock); + return (0); +} + +void +zfs_dbgmsg_init(void) +{ + procfs_list_install("zfs", + NULL, + "dbgmsg", + 0600, + &zfs_dbgmsgs, + zfs_dbgmsg_show, + zfs_dbgmsg_show_header, + zfs_dbgmsg_clear, + offsetof(zfs_dbgmsg_t, zdm_node)); +} + +void +zfs_dbgmsg_fini(void) +{ + procfs_list_uninstall(&zfs_dbgmsgs); + zfs_dbgmsg_purge(0); + + procfs_list_destroy(&zfs_dbgmsgs); +} + +void +__set_error(const char *file, const char *func, int line, int err) +{ + /* + * To enable this: + * + * $ echo 512 >/sys/module/zfs/parameters/zfs_flags + */ + if (zfs_flags & ZFS_DEBUG_SET_ERROR) + __dprintf(B_FALSE, file, func, line, "error %lu", + (ulong_t)err); +} + +void +__zfs_dbgmsg(char *buf) +{ + uint_t size = sizeof (zfs_dbgmsg_t) + strlen(buf) + 1; + zfs_dbgmsg_t *zdm = kmem_zalloc(size, KM_SLEEP); + zdm->zdm_size = size; + zdm->zdm_timestamp = gethrestime_sec(); + strcpy(zdm->zdm_msg, buf); + + mutex_enter(&zfs_dbgmsgs.pl_lock); + procfs_list_add(&zfs_dbgmsgs, zdm); + zfs_dbgmsg_size += size; + zfs_dbgmsg_purge(zfs_dbgmsg_maxsize); + mutex_exit(&zfs_dbgmsgs.pl_lock); +} + +void +__dprintf(boolean_t dprint, const char *file, const char *func, + int line, const char *fmt, ...) +{ + const char *newfile; + va_list adx; + size_t size; + char *buf; + char *nl; + int i; + char *prefix = (dprint) ? "dprintf: " : ""; + + size = 1024; + buf = kmem_alloc(size, KM_SLEEP); + + /* + * Get rid of annoying prefix to filename. + */ + newfile = strrchr(file, '/'); + if (newfile != NULL) { + newfile = newfile + 1; /* Get rid of leading / */ + } else { + newfile = file; + } + + i = snprintf(buf, size, "%px %s%s:%d:%s(): ", + curthread, prefix, newfile, line, func); + + if (i < size) { + va_start(adx, fmt); + (void) vsnprintf(buf + i, size - i, fmt, adx); + va_end(adx); + } + + /* + * Get rid of trailing newline for dprintf logs. + */ + if (dprint && buf[0] != '\0') { + nl = &buf[strlen(buf) - 1]; + if (*nl == '\n') + *nl = '\0'; + } + + /* + * To get this data enable the zfs__dprintf trace point as shown: + * + * # Enable zfs__dprintf tracepoint, clear the tracepoint ring buffer + * $ echo 1 > /sys/kernel/debug/tracing/events/zfs/enable + * $ echo 0 > /sys/kernel/debug/tracing/trace + * + * # Dump the ring buffer. + * $ cat /sys/kernel/debug/tracing/trace + */ + DTRACE_PROBE1(zfs__dprintf, char *, buf); + + /* + * To get this data: + * + * $ cat /proc/spl/kstat/zfs/dbgmsg + * + * To clear the buffer: + * $ echo 0 > /proc/spl/kstat/zfs/dbgmsg + */ + __zfs_dbgmsg(buf); + + kmem_free(buf, size); +} + +module_param(zfs_dbgmsg_enable, int, 0644); +MODULE_PARM_DESC(zfs_dbgmsg_enable, "Enable ZFS debug message log"); + +module_param(zfs_dbgmsg_maxsize, uint, 0644); +MODULE_PARM_DESC(zfs_dbgmsg_maxsize, "Maximum ZFS debug log size"); |