[PATCH] OCFS2: The Second Oracle Cluster Filesystem
A distributed lock manager built with the cluster file system use case in mind. The OCFS2 dlm exposes a VMS style API, though things have been simplified internally. The only lock levels implemented currently are NLMODE, PRMODE and EXMODE. Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com> Signed-off-by: Kurt Hackel <kurt.hackel@oracle.com>
This commit is contained in:
Kurt Hackel
695
fs/ocfs2/dlm/dlmthread.c
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695
fs/ocfs2/dlm/dlmthread.c
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@@ -0,0 +1,695 @@
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/* -*- mode: c; c-basic-offset: 8; -*-
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* vim: noexpandtab sw=8 ts=8 sts=0:
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*
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* dlmthread.c
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*
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* standalone DLM module
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*
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* Copyright (C) 2004 Oracle. All rights reserved.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public
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* License as published by the Free Software Foundation; either
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* version 2 of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public
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* License along with this program; if not, write to the
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* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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* Boston, MA 021110-1307, USA.
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*
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*/
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#include <linux/module.h>
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#include <linux/fs.h>
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#include <linux/types.h>
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#include <linux/slab.h>
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#include <linux/highmem.h>
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#include <linux/utsname.h>
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#include <linux/init.h>
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#include <linux/sysctl.h>
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#include <linux/random.h>
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#include <linux/blkdev.h>
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#include <linux/socket.h>
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#include <linux/inet.h>
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#include <linux/timer.h>
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#include <linux/kthread.h>
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#include "cluster/heartbeat.h"
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#include "cluster/nodemanager.h"
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#include "cluster/tcp.h"
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#include "dlmapi.h"
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#include "dlmcommon.h"
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#include "dlmdomain.h"
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#define MLOG_MASK_PREFIX (ML_DLM|ML_DLM_THREAD)
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#include "cluster/masklog.h"
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extern spinlock_t dlm_domain_lock;
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extern struct list_head dlm_domains;
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static int dlm_thread(void *data);
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static void dlm_flush_asts(struct dlm_ctxt *dlm);
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#define dlm_lock_is_remote(dlm, lock) ((lock)->ml.node != (dlm)->node_num)
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/* will exit holding res->spinlock, but may drop in function */
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/* waits until flags are cleared on res->state */
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void __dlm_wait_on_lockres_flags(struct dlm_lock_resource *res, int flags)
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{
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DECLARE_WAITQUEUE(wait, current);
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assert_spin_locked(&res->spinlock);
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add_wait_queue(&res->wq, &wait);
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repeat:
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set_current_state(TASK_UNINTERRUPTIBLE);
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if (res->state & flags) {
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spin_unlock(&res->spinlock);
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schedule();
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spin_lock(&res->spinlock);
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goto repeat;
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}
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remove_wait_queue(&res->wq, &wait);
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current->state = TASK_RUNNING;
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}
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static int __dlm_lockres_unused(struct dlm_lock_resource *res)
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{
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if (list_empty(&res->granted) &&
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list_empty(&res->converting) &&
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list_empty(&res->blocked) &&
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list_empty(&res->dirty))
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return 1;
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return 0;
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}
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/* Call whenever you may have added or deleted something from one of
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* the lockres queue's. This will figure out whether it belongs on the
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* unused list or not and does the appropriate thing. */
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void __dlm_lockres_calc_usage(struct dlm_ctxt *dlm,
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struct dlm_lock_resource *res)
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{
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mlog_entry("%.*s\n", res->lockname.len, res->lockname.name);
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assert_spin_locked(&dlm->spinlock);
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assert_spin_locked(&res->spinlock);
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if (__dlm_lockres_unused(res)){
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if (list_empty(&res->purge)) {
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mlog(0, "putting lockres %.*s from purge list\n",
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res->lockname.len, res->lockname.name);
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res->last_used = jiffies;
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list_add_tail(&res->purge, &dlm->purge_list);
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dlm->purge_count++;
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}
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} else if (!list_empty(&res->purge)) {
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mlog(0, "removing lockres %.*s from purge list\n",
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res->lockname.len, res->lockname.name);
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list_del_init(&res->purge);
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dlm->purge_count--;
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}
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}
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void dlm_lockres_calc_usage(struct dlm_ctxt *dlm,
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struct dlm_lock_resource *res)
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{
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mlog_entry("%.*s\n", res->lockname.len, res->lockname.name);
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spin_lock(&dlm->spinlock);
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spin_lock(&res->spinlock);
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__dlm_lockres_calc_usage(dlm, res);
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spin_unlock(&res->spinlock);
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spin_unlock(&dlm->spinlock);
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}
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/* TODO: Eventual API: Called with the dlm spinlock held, may drop it
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* to do migration, but will re-acquire before exit. */
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void dlm_purge_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *lockres)
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{
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int master;
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int ret;
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spin_lock(&lockres->spinlock);
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master = lockres->owner == dlm->node_num;
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spin_unlock(&lockres->spinlock);
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mlog(0, "purging lockres %.*s, master = %d\n", lockres->lockname.len,
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lockres->lockname.name, master);
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/* Non master is the easy case -- no migration required, just
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* quit. */
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if (!master)
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goto finish;
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/* Wheee! Migrate lockres here! */
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spin_unlock(&dlm->spinlock);
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again:
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ret = dlm_migrate_lockres(dlm, lockres, O2NM_MAX_NODES);
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if (ret == -ENOTEMPTY) {
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mlog(ML_ERROR, "lockres %.*s still has local locks!\n",
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lockres->lockname.len, lockres->lockname.name);
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BUG();
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} else if (ret < 0) {
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mlog(ML_NOTICE, "lockres %.*s: migrate failed, retrying\n",
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lockres->lockname.len, lockres->lockname.name);
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goto again;
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}
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spin_lock(&dlm->spinlock);
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finish:
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if (!list_empty(&lockres->purge)) {
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list_del_init(&lockres->purge);
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dlm->purge_count--;
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}
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__dlm_unhash_lockres(lockres);
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}
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static void dlm_run_purge_list(struct dlm_ctxt *dlm,
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int purge_now)
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{
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unsigned int run_max, unused;
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unsigned long purge_jiffies;
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struct dlm_lock_resource *lockres;
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spin_lock(&dlm->spinlock);
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run_max = dlm->purge_count;
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while(run_max && !list_empty(&dlm->purge_list)) {
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run_max--;
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lockres = list_entry(dlm->purge_list.next,
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struct dlm_lock_resource, purge);
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/* Status of the lockres *might* change so double
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* check. If the lockres is unused, holding the dlm
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* spinlock will prevent people from getting and more
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* refs on it -- there's no need to keep the lockres
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* spinlock. */
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spin_lock(&lockres->spinlock);
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unused = __dlm_lockres_unused(lockres);
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spin_unlock(&lockres->spinlock);
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if (!unused)
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continue;
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purge_jiffies = lockres->last_used +
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msecs_to_jiffies(DLM_PURGE_INTERVAL_MS);
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/* Make sure that we want to be processing this guy at
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* this time. */
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if (!purge_now && time_after(purge_jiffies, jiffies)) {
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/* Since resources are added to the purge list
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* in tail order, we can stop at the first
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* unpurgable resource -- anyone added after
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* him will have a greater last_used value */
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break;
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}
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list_del_init(&lockres->purge);
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dlm->purge_count--;
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/* This may drop and reacquire the dlm spinlock if it
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* has to do migration. */
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mlog(0, "calling dlm_purge_lockres!\n");
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dlm_purge_lockres(dlm, lockres);
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mlog(0, "DONE calling dlm_purge_lockres!\n");
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/* Avoid adding any scheduling latencies */
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cond_resched_lock(&dlm->spinlock);
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}
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spin_unlock(&dlm->spinlock);
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}
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static void dlm_shuffle_lists(struct dlm_ctxt *dlm,
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struct dlm_lock_resource *res)
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{
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struct dlm_lock *lock, *target;
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struct list_head *iter;
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struct list_head *head;
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int can_grant = 1;
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//mlog(0, "res->lockname.len=%d\n", res->lockname.len);
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//mlog(0, "res->lockname.name=%p\n", res->lockname.name);
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//mlog(0, "shuffle res %.*s\n", res->lockname.len,
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// res->lockname.name);
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/* because this function is called with the lockres
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* spinlock, and because we know that it is not migrating/
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* recovering/in-progress, it is fine to reserve asts and
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* basts right before queueing them all throughout */
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assert_spin_locked(&res->spinlock);
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BUG_ON((res->state & (DLM_LOCK_RES_MIGRATING|
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DLM_LOCK_RES_RECOVERING|
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DLM_LOCK_RES_IN_PROGRESS)));
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converting:
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if (list_empty(&res->converting))
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goto blocked;
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mlog(0, "res %.*s has locks on a convert queue\n", res->lockname.len,
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res->lockname.name);
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target = list_entry(res->converting.next, struct dlm_lock, list);
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if (target->ml.convert_type == LKM_IVMODE) {
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mlog(ML_ERROR, "%.*s: converting a lock with no "
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"convert_type!\n", res->lockname.len, res->lockname.name);
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BUG();
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}
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head = &res->granted;
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list_for_each(iter, head) {
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lock = list_entry(iter, struct dlm_lock, list);
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if (lock==target)
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continue;
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if (!dlm_lock_compatible(lock->ml.type,
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target->ml.convert_type)) {
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can_grant = 0;
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/* queue the BAST if not already */
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if (lock->ml.highest_blocked == LKM_IVMODE) {
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__dlm_lockres_reserve_ast(res);
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dlm_queue_bast(dlm, lock);
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}
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/* update the highest_blocked if needed */
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if (lock->ml.highest_blocked < target->ml.convert_type)
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lock->ml.highest_blocked =
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target->ml.convert_type;
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}
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}
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head = &res->converting;
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list_for_each(iter, head) {
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lock = list_entry(iter, struct dlm_lock, list);
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if (lock==target)
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continue;
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if (!dlm_lock_compatible(lock->ml.type,
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target->ml.convert_type)) {
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can_grant = 0;
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if (lock->ml.highest_blocked == LKM_IVMODE) {
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__dlm_lockres_reserve_ast(res);
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dlm_queue_bast(dlm, lock);
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}
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if (lock->ml.highest_blocked < target->ml.convert_type)
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lock->ml.highest_blocked =
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target->ml.convert_type;
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}
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}
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/* we can convert the lock */
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if (can_grant) {
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spin_lock(&target->spinlock);
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BUG_ON(target->ml.highest_blocked != LKM_IVMODE);
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mlog(0, "calling ast for converting lock: %.*s, have: %d, "
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"granting: %d, node: %u\n", res->lockname.len,
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res->lockname.name, target->ml.type,
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target->ml.convert_type, target->ml.node);
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target->ml.type = target->ml.convert_type;
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target->ml.convert_type = LKM_IVMODE;
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list_del_init(&target->list);
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list_add_tail(&target->list, &res->granted);
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BUG_ON(!target->lksb);
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target->lksb->status = DLM_NORMAL;
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spin_unlock(&target->spinlock);
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__dlm_lockres_reserve_ast(res);
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dlm_queue_ast(dlm, target);
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/* go back and check for more */
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goto converting;
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}
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blocked:
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if (list_empty(&res->blocked))
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goto leave;
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target = list_entry(res->blocked.next, struct dlm_lock, list);
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head = &res->granted;
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list_for_each(iter, head) {
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lock = list_entry(iter, struct dlm_lock, list);
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if (lock==target)
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continue;
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if (!dlm_lock_compatible(lock->ml.type, target->ml.type)) {
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can_grant = 0;
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if (lock->ml.highest_blocked == LKM_IVMODE) {
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__dlm_lockres_reserve_ast(res);
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dlm_queue_bast(dlm, lock);
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}
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if (lock->ml.highest_blocked < target->ml.type)
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lock->ml.highest_blocked = target->ml.type;
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}
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}
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head = &res->converting;
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list_for_each(iter, head) {
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lock = list_entry(iter, struct dlm_lock, list);
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if (lock==target)
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continue;
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if (!dlm_lock_compatible(lock->ml.type, target->ml.type)) {
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can_grant = 0;
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if (lock->ml.highest_blocked == LKM_IVMODE) {
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__dlm_lockres_reserve_ast(res);
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dlm_queue_bast(dlm, lock);
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}
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if (lock->ml.highest_blocked < target->ml.type)
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lock->ml.highest_blocked = target->ml.type;
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}
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}
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/* we can grant the blocked lock (only
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* possible if converting list empty) */
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if (can_grant) {
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spin_lock(&target->spinlock);
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BUG_ON(target->ml.highest_blocked != LKM_IVMODE);
|
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|
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mlog(0, "calling ast for blocked lock: %.*s, granting: %d, "
|
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"node: %u\n", res->lockname.len, res->lockname.name,
|
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target->ml.type, target->ml.node);
|
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// target->ml.type is already correct
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list_del_init(&target->list);
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list_add_tail(&target->list, &res->granted);
|
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|
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BUG_ON(!target->lksb);
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target->lksb->status = DLM_NORMAL;
|
||||
|
||||
spin_unlock(&target->spinlock);
|
||||
|
||||
__dlm_lockres_reserve_ast(res);
|
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dlm_queue_ast(dlm, target);
|
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/* go back and check for more */
|
||||
goto converting;
|
||||
}
|
||||
|
||||
leave:
|
||||
return;
|
||||
}
|
||||
|
||||
/* must have NO locks when calling this with res !=NULL * */
|
||||
void dlm_kick_thread(struct dlm_ctxt *dlm, struct dlm_lock_resource *res)
|
||||
{
|
||||
mlog_entry("dlm=%p, res=%p\n", dlm, res);
|
||||
if (res) {
|
||||
spin_lock(&dlm->spinlock);
|
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spin_lock(&res->spinlock);
|
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__dlm_dirty_lockres(dlm, res);
|
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spin_unlock(&res->spinlock);
|
||||
spin_unlock(&dlm->spinlock);
|
||||
}
|
||||
wake_up(&dlm->dlm_thread_wq);
|
||||
}
|
||||
|
||||
void __dlm_dirty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res)
|
||||
{
|
||||
mlog_entry("dlm=%p, res=%p\n", dlm, res);
|
||||
|
||||
assert_spin_locked(&dlm->spinlock);
|
||||
assert_spin_locked(&res->spinlock);
|
||||
|
||||
/* don't shuffle secondary queues */
|
||||
if ((res->owner == dlm->node_num) &&
|
||||
!(res->state & DLM_LOCK_RES_DIRTY)) {
|
||||
list_add_tail(&res->dirty, &dlm->dirty_list);
|
||||
res->state |= DLM_LOCK_RES_DIRTY;
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
/* Launch the NM thread for the mounted volume */
|
||||
int dlm_launch_thread(struct dlm_ctxt *dlm)
|
||||
{
|
||||
mlog(0, "starting dlm thread...\n");
|
||||
|
||||
dlm->dlm_thread_task = kthread_run(dlm_thread, dlm, "dlm_thread");
|
||||
if (IS_ERR(dlm->dlm_thread_task)) {
|
||||
mlog_errno(PTR_ERR(dlm->dlm_thread_task));
|
||||
dlm->dlm_thread_task = NULL;
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
void dlm_complete_thread(struct dlm_ctxt *dlm)
|
||||
{
|
||||
if (dlm->dlm_thread_task) {
|
||||
mlog(ML_KTHREAD, "waiting for dlm thread to exit\n");
|
||||
kthread_stop(dlm->dlm_thread_task);
|
||||
dlm->dlm_thread_task = NULL;
|
||||
}
|
||||
}
|
||||
|
||||
static int dlm_dirty_list_empty(struct dlm_ctxt *dlm)
|
||||
{
|
||||
int empty;
|
||||
|
||||
spin_lock(&dlm->spinlock);
|
||||
empty = list_empty(&dlm->dirty_list);
|
||||
spin_unlock(&dlm->spinlock);
|
||||
|
||||
return empty;
|
||||
}
|
||||
|
||||
static void dlm_flush_asts(struct dlm_ctxt *dlm)
|
||||
{
|
||||
int ret;
|
||||
struct dlm_lock *lock;
|
||||
struct dlm_lock_resource *res;
|
||||
u8 hi;
|
||||
|
||||
spin_lock(&dlm->ast_lock);
|
||||
while (!list_empty(&dlm->pending_asts)) {
|
||||
lock = list_entry(dlm->pending_asts.next,
|
||||
struct dlm_lock, ast_list);
|
||||
/* get an extra ref on lock */
|
||||
dlm_lock_get(lock);
|
||||
res = lock->lockres;
|
||||
mlog(0, "delivering an ast for this lockres\n");
|
||||
|
||||
BUG_ON(!lock->ast_pending);
|
||||
|
||||
/* remove from list (including ref) */
|
||||
list_del_init(&lock->ast_list);
|
||||
dlm_lock_put(lock);
|
||||
spin_unlock(&dlm->ast_lock);
|
||||
|
||||
if (lock->ml.node != dlm->node_num) {
|
||||
ret = dlm_do_remote_ast(dlm, res, lock);
|
||||
if (ret < 0)
|
||||
mlog_errno(ret);
|
||||
} else
|
||||
dlm_do_local_ast(dlm, res, lock);
|
||||
|
||||
spin_lock(&dlm->ast_lock);
|
||||
|
||||
/* possible that another ast was queued while
|
||||
* we were delivering the last one */
|
||||
if (!list_empty(&lock->ast_list)) {
|
||||
mlog(0, "aha another ast got queued while "
|
||||
"we were finishing the last one. will "
|
||||
"keep the ast_pending flag set.\n");
|
||||
} else
|
||||
lock->ast_pending = 0;
|
||||
|
||||
/* drop the extra ref.
|
||||
* this may drop it completely. */
|
||||
dlm_lock_put(lock);
|
||||
dlm_lockres_release_ast(dlm, res);
|
||||
}
|
||||
|
||||
while (!list_empty(&dlm->pending_basts)) {
|
||||
lock = list_entry(dlm->pending_basts.next,
|
||||
struct dlm_lock, bast_list);
|
||||
/* get an extra ref on lock */
|
||||
dlm_lock_get(lock);
|
||||
res = lock->lockres;
|
||||
|
||||
BUG_ON(!lock->bast_pending);
|
||||
|
||||
/* get the highest blocked lock, and reset */
|
||||
spin_lock(&lock->spinlock);
|
||||
BUG_ON(lock->ml.highest_blocked <= LKM_IVMODE);
|
||||
hi = lock->ml.highest_blocked;
|
||||
lock->ml.highest_blocked = LKM_IVMODE;
|
||||
spin_unlock(&lock->spinlock);
|
||||
|
||||
/* remove from list (including ref) */
|
||||
list_del_init(&lock->bast_list);
|
||||
dlm_lock_put(lock);
|
||||
spin_unlock(&dlm->ast_lock);
|
||||
|
||||
mlog(0, "delivering a bast for this lockres "
|
||||
"(blocked = %d\n", hi);
|
||||
|
||||
if (lock->ml.node != dlm->node_num) {
|
||||
ret = dlm_send_proxy_bast(dlm, res, lock, hi);
|
||||
if (ret < 0)
|
||||
mlog_errno(ret);
|
||||
} else
|
||||
dlm_do_local_bast(dlm, res, lock, hi);
|
||||
|
||||
spin_lock(&dlm->ast_lock);
|
||||
|
||||
/* possible that another bast was queued while
|
||||
* we were delivering the last one */
|
||||
if (!list_empty(&lock->bast_list)) {
|
||||
mlog(0, "aha another bast got queued while "
|
||||
"we were finishing the last one. will "
|
||||
"keep the bast_pending flag set.\n");
|
||||
} else
|
||||
lock->bast_pending = 0;
|
||||
|
||||
/* drop the extra ref.
|
||||
* this may drop it completely. */
|
||||
dlm_lock_put(lock);
|
||||
dlm_lockres_release_ast(dlm, res);
|
||||
}
|
||||
wake_up(&dlm->ast_wq);
|
||||
spin_unlock(&dlm->ast_lock);
|
||||
}
|
||||
|
||||
|
||||
#define DLM_THREAD_TIMEOUT_MS (4 * 1000)
|
||||
#define DLM_THREAD_MAX_DIRTY 100
|
||||
#define DLM_THREAD_MAX_ASTS 10
|
||||
|
||||
static int dlm_thread(void *data)
|
||||
{
|
||||
struct dlm_lock_resource *res;
|
||||
struct dlm_ctxt *dlm = data;
|
||||
unsigned long timeout = msecs_to_jiffies(DLM_THREAD_TIMEOUT_MS);
|
||||
|
||||
mlog(0, "dlm thread running for %s...\n", dlm->name);
|
||||
|
||||
while (!kthread_should_stop()) {
|
||||
int n = DLM_THREAD_MAX_DIRTY;
|
||||
|
||||
/* dlm_shutting_down is very point-in-time, but that
|
||||
* doesn't matter as we'll just loop back around if we
|
||||
* get false on the leading edge of a state
|
||||
* transition. */
|
||||
dlm_run_purge_list(dlm, dlm_shutting_down(dlm));
|
||||
|
||||
/* We really don't want to hold dlm->spinlock while
|
||||
* calling dlm_shuffle_lists on each lockres that
|
||||
* needs to have its queues adjusted and AST/BASTs
|
||||
* run. So let's pull each entry off the dirty_list
|
||||
* and drop dlm->spinlock ASAP. Once off the list,
|
||||
* res->spinlock needs to be taken again to protect
|
||||
* the queues while calling dlm_shuffle_lists. */
|
||||
spin_lock(&dlm->spinlock);
|
||||
while (!list_empty(&dlm->dirty_list)) {
|
||||
int delay = 0;
|
||||
res = list_entry(dlm->dirty_list.next,
|
||||
struct dlm_lock_resource, dirty);
|
||||
|
||||
/* peel a lockres off, remove it from the list,
|
||||
* unset the dirty flag and drop the dlm lock */
|
||||
BUG_ON(!res);
|
||||
dlm_lockres_get(res);
|
||||
|
||||
spin_lock(&res->spinlock);
|
||||
res->state &= ~DLM_LOCK_RES_DIRTY;
|
||||
list_del_init(&res->dirty);
|
||||
spin_unlock(&res->spinlock);
|
||||
spin_unlock(&dlm->spinlock);
|
||||
|
||||
/* lockres can be re-dirtied/re-added to the
|
||||
* dirty_list in this gap, but that is ok */
|
||||
|
||||
spin_lock(&res->spinlock);
|
||||
if (res->owner != dlm->node_num) {
|
||||
__dlm_print_one_lock_resource(res);
|
||||
mlog(ML_ERROR, "inprog:%s, mig:%s, reco:%s, dirty:%s\n",
|
||||
res->state & DLM_LOCK_RES_IN_PROGRESS ? "yes" : "no",
|
||||
res->state & DLM_LOCK_RES_MIGRATING ? "yes" : "no",
|
||||
res->state & DLM_LOCK_RES_RECOVERING ? "yes" : "no",
|
||||
res->state & DLM_LOCK_RES_DIRTY ? "yes" : "no");
|
||||
}
|
||||
BUG_ON(res->owner != dlm->node_num);
|
||||
|
||||
/* it is now ok to move lockreses in these states
|
||||
* to the dirty list, assuming that they will only be
|
||||
* dirty for a short while. */
|
||||
if (res->state & (DLM_LOCK_RES_IN_PROGRESS |
|
||||
DLM_LOCK_RES_MIGRATING |
|
||||
DLM_LOCK_RES_RECOVERING)) {
|
||||
/* move it to the tail and keep going */
|
||||
spin_unlock(&res->spinlock);
|
||||
mlog(0, "delaying list shuffling for in-"
|
||||
"progress lockres %.*s, state=%d\n",
|
||||
res->lockname.len, res->lockname.name,
|
||||
res->state);
|
||||
delay = 1;
|
||||
goto in_progress;
|
||||
}
|
||||
|
||||
/* at this point the lockres is not migrating/
|
||||
* recovering/in-progress. we have the lockres
|
||||
* spinlock and do NOT have the dlm lock.
|
||||
* safe to reserve/queue asts and run the lists. */
|
||||
|
||||
mlog(0, "calling dlm_shuffle_lists with dlm=%p, "
|
||||
"res=%p\n", dlm, res);
|
||||
|
||||
/* called while holding lockres lock */
|
||||
dlm_shuffle_lists(dlm, res);
|
||||
spin_unlock(&res->spinlock);
|
||||
|
||||
dlm_lockres_calc_usage(dlm, res);
|
||||
|
||||
in_progress:
|
||||
|
||||
spin_lock(&dlm->spinlock);
|
||||
/* if the lock was in-progress, stick
|
||||
* it on the back of the list */
|
||||
if (delay) {
|
||||
spin_lock(&res->spinlock);
|
||||
list_add_tail(&res->dirty, &dlm->dirty_list);
|
||||
res->state |= DLM_LOCK_RES_DIRTY;
|
||||
spin_unlock(&res->spinlock);
|
||||
}
|
||||
dlm_lockres_put(res);
|
||||
|
||||
/* unlikely, but we may need to give time to
|
||||
* other tasks */
|
||||
if (!--n) {
|
||||
mlog(0, "throttling dlm_thread\n");
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
spin_unlock(&dlm->spinlock);
|
||||
dlm_flush_asts(dlm);
|
||||
|
||||
/* yield and continue right away if there is more work to do */
|
||||
if (!n) {
|
||||
yield();
|
||||
continue;
|
||||
}
|
||||
|
||||
wait_event_interruptible_timeout(dlm->dlm_thread_wq,
|
||||
!dlm_dirty_list_empty(dlm) ||
|
||||
kthread_should_stop(),
|
||||
timeout);
|
||||
}
|
||||
|
||||
mlog(0, "quitting DLM thread\n");
|
||||
return 0;
|
||||
}
|
||||
Reference in New Issue
Block a user