3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling/*
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling * CDDL HEADER START
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling *
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling * The contents of this file are subject to the terms of the
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling * Common Development and Distribution License (the "License").
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling * You may not use this file except in compliance with the License.
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling *
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling * or http://www.opensolaris.org/os/licensing.
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling * See the License for the specific language governing permissions
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling * and limitations under the License.
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling *
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling * When distributing Covered Code, include this CDDL HEADER in each
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling * If applicable, add the following below this CDDL HEADER, with the
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling * fields enclosed by brackets "[]" replaced with your own identifying
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling * information: Portions Copyright [yyyy] [name of copyright owner]
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling *
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling * CDDL HEADER END
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling */
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling/*
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
2a104a5236475eb73aa41eaaf3ed9f3ccbe0ca55Alex Reece * Copyright (c) 2012, 2014 by Delphix. All rights reserved.
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling */
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling#include <sys/zfs_context.h>
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Linglist_t zfs_dbgmsgs;
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Lingint zfs_dbgmsg_size;
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Lingkmutex_t zfs_dbgmsgs_lock;
7fd05ac4dec0c343d2f68f310d3718b715ecfbafMatthew Ahrensint zfs_dbgmsg_maxsize = 4<<20; /* 4MB */
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Lingvoid
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Lingzfs_dbgmsg_init(void)
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling{
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling list_create(&zfs_dbgmsgs, sizeof (zfs_dbgmsg_t),
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling offsetof(zfs_dbgmsg_t, zdm_node));
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling mutex_init(&zfs_dbgmsgs_lock, NULL, MUTEX_DEFAULT, NULL);
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling}
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Lingvoid
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Lingzfs_dbgmsg_fini(void)
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling{
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling zfs_dbgmsg_t *zdm;
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling while ((zdm = list_remove_head(&zfs_dbgmsgs)) != NULL) {
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling int size = sizeof (zfs_dbgmsg_t) + strlen(zdm->zdm_msg);
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling kmem_free(zdm, size);
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling zfs_dbgmsg_size -= size;
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling }
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling mutex_destroy(&zfs_dbgmsgs_lock);
fb09f5aad449c97fe309678f3f604982b563a96fMadhav Suresh ASSERT0(zfs_dbgmsg_size);
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling}
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling/*
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling * Print these messages by running:
fb09f5aad449c97fe309678f3f604982b563a96fMadhav Suresh * echo ::zfs_dbgmsg | mdb -k
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling *
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling * Monitor these messages by running:
2a104a5236475eb73aa41eaaf3ed9f3ccbe0ca55Alex Reece * dtrace -qn 'zfs-dbgmsg{printf("%s\n", stringof(arg0))}'
2a104a5236475eb73aa41eaaf3ed9f3ccbe0ca55Alex Reece *
2a104a5236475eb73aa41eaaf3ed9f3ccbe0ca55Alex Reece * When used with libzpool, monitor with:
2a104a5236475eb73aa41eaaf3ed9f3ccbe0ca55Alex Reece * dtrace -qn 'zfs$pid::zfs_dbgmsg:probe1{printf("%s\n", copyinstr(arg1))}'
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling */
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Lingvoid
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Lingzfs_dbgmsg(const char *fmt, ...)
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling{
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling int size;
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling va_list adx;
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling zfs_dbgmsg_t *zdm;
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling va_start(adx, fmt);
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling size = vsnprintf(NULL, 0, fmt, adx);
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling va_end(adx);
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling /*
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling * There is one byte of string in sizeof (zfs_dbgmsg_t), used
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling * for the terminating null.
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling */
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling zdm = kmem_alloc(sizeof (zfs_dbgmsg_t) + size, KM_SLEEP);
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling zdm->zdm_timestamp = gethrestime_sec();
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling va_start(adx, fmt);
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling (void) vsnprintf(zdm->zdm_msg, size + 1, fmt, adx);
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling va_end(adx);
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling DTRACE_PROBE1(zfs__dbgmsg, char *, zdm->zdm_msg);
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling mutex_enter(&zfs_dbgmsgs_lock);
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling list_insert_tail(&zfs_dbgmsgs, zdm);
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling zfs_dbgmsg_size += sizeof (zfs_dbgmsg_t) + size;
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling while (zfs_dbgmsg_size > zfs_dbgmsg_maxsize) {
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling zdm = list_remove_head(&zfs_dbgmsgs);
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling size = sizeof (zfs_dbgmsg_t) + strlen(zdm->zdm_msg);
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling kmem_free(zdm, size);
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling zfs_dbgmsg_size -= size;
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling }
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling mutex_exit(&zfs_dbgmsgs_lock);
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling}
b4952e17e8858d3225793b28788278de9fe6038dGeorge Wilson
b4952e17e8858d3225793b28788278de9fe6038dGeorge Wilsonvoid
b4952e17e8858d3225793b28788278de9fe6038dGeorge Wilsonzfs_dbgmsg_print(const char *tag)
b4952e17e8858d3225793b28788278de9fe6038dGeorge Wilson{
b4952e17e8858d3225793b28788278de9fe6038dGeorge Wilson zfs_dbgmsg_t *zdm;
b4952e17e8858d3225793b28788278de9fe6038dGeorge Wilson
b4952e17e8858d3225793b28788278de9fe6038dGeorge Wilson (void) printf("ZFS_DBGMSG(%s):\n", tag);
b4952e17e8858d3225793b28788278de9fe6038dGeorge Wilson mutex_enter(&zfs_dbgmsgs_lock);
b4952e17e8858d3225793b28788278de9fe6038dGeorge Wilson for (zdm = list_head(&zfs_dbgmsgs); zdm;
b4952e17e8858d3225793b28788278de9fe6038dGeorge Wilson zdm = list_next(&zfs_dbgmsgs, zdm))
b4952e17e8858d3225793b28788278de9fe6038dGeorge Wilson (void) printf("%s\n", zdm->zdm_msg);
b4952e17e8858d3225793b28788278de9fe6038dGeorge Wilson mutex_exit(&zfs_dbgmsgs_lock);
b4952e17e8858d3225793b28788278de9fe6038dGeorge Wilson}