// SPDX-License-Identifier: GPL-2.0-or-later
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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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#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/highmem.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 <linux/delay.h>
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|
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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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static int dlm_thread(void *data);
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static void dlm_flush_asts(struct dlm_ctxt *dlm);
|
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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);
|
schedule();
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spin_lock(&res->spinlock);
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goto repeat;
|
}
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remove_wait_queue(&res->wq, &wait);
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__set_current_state(TASK_RUNNING);
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}
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int __dlm_lockres_has_locks(struct dlm_lock_resource *res)
|
{
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if (list_empty(&res->granted) &&
|
list_empty(&res->converting) &&
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list_empty(&res->blocked))
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return 0;
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return 1;
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}
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/* "unused": the lockres has no locks, is not on the dirty list,
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* has no inflight locks (in the gap between mastery and acquiring
|
* the first lock), and has no bits in its refmap.
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* truly ready to be freed. */
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int __dlm_lockres_unused(struct dlm_lock_resource *res)
|
{
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int bit;
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|
assert_spin_locked(&res->spinlock);
|
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if (__dlm_lockres_has_locks(res))
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return 0;
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/* Locks are in the process of being created */
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if (res->inflight_locks)
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return 0;
|
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if (!list_empty(&res->dirty) || res->state & DLM_LOCK_RES_DIRTY)
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return 0;
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if (res->state & (DLM_LOCK_RES_RECOVERING|
|
DLM_LOCK_RES_RECOVERY_WAITING))
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return 0;
|
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/* Another node has this resource with this node as the master */
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bit = find_next_bit(res->refmap, O2NM_MAX_NODES, 0);
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if (bit < O2NM_MAX_NODES)
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return 0;
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return 1;
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}
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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
|
* 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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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, "%s: Adding res %.*s to purge list\n",
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dlm->name, res->lockname.len, res->lockname.name);
|
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res->last_used = jiffies;
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dlm_lockres_get(res);
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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, "%s: Removing res %.*s from purge list\n",
|
dlm->name, res->lockname.len, res->lockname.name);
|
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list_del_init(&res->purge);
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dlm_lockres_put(res);
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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,
|
struct dlm_lock_resource *res)
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{
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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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/*
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* Do the real purge work:
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* unhash the lockres, and
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* clear flag DLM_LOCK_RES_DROPPING_REF.
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* It requires dlm and lockres spinlock to be taken.
|
*/
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void __dlm_do_purge_lockres(struct dlm_ctxt *dlm,
|
struct dlm_lock_resource *res)
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{
|
assert_spin_locked(&dlm->spinlock);
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assert_spin_locked(&res->spinlock);
|
|
if (!list_empty(&res->purge)) {
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mlog(0, "%s: Removing res %.*s from purgelist\n",
|
dlm->name, res->lockname.len, res->lockname.name);
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list_del_init(&res->purge);
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dlm_lockres_put(res);
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dlm->purge_count--;
|
}
|
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if (!__dlm_lockres_unused(res)) {
|
mlog(ML_ERROR, "%s: res %.*s in use after deref\n",
|
dlm->name, res->lockname.len, res->lockname.name);
|
__dlm_print_one_lock_resource(res);
|
BUG();
|
}
|
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__dlm_unhash_lockres(dlm, res);
|
|
spin_lock(&dlm->track_lock);
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if (!list_empty(&res->tracking))
|
list_del_init(&res->tracking);
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else {
|
mlog(ML_ERROR, "%s: Resource %.*s not on the Tracking list\n",
|
dlm->name, res->lockname.len, res->lockname.name);
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__dlm_print_one_lock_resource(res);
|
}
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spin_unlock(&dlm->track_lock);
|
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/*
|
* lockres is not in the hash now. drop the flag and wake up
|
* any processes waiting in dlm_get_lock_resource.
|
*/
|
res->state &= ~DLM_LOCK_RES_DROPPING_REF;
|
}
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|
static void dlm_purge_lockres(struct dlm_ctxt *dlm,
|
struct dlm_lock_resource *res)
|
{
|
int master;
|
int ret = 0;
|
|
assert_spin_locked(&dlm->spinlock);
|
assert_spin_locked(&res->spinlock);
|
|
master = (res->owner == dlm->node_num);
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|
mlog(0, "%s: Purging res %.*s, master %d\n", dlm->name,
|
res->lockname.len, res->lockname.name, master);
|
|
if (!master) {
|
if (res->state & DLM_LOCK_RES_DROPPING_REF) {
|
mlog(ML_NOTICE, "%s: res %.*s already in DLM_LOCK_RES_DROPPING_REF state\n",
|
dlm->name, res->lockname.len, res->lockname.name);
|
spin_unlock(&res->spinlock);
|
return;
|
}
|
|
res->state |= DLM_LOCK_RES_DROPPING_REF;
|
/* drop spinlock... retake below */
|
spin_unlock(&res->spinlock);
|
spin_unlock(&dlm->spinlock);
|
|
spin_lock(&res->spinlock);
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/* This ensures that clear refmap is sent after the set */
|
__dlm_wait_on_lockres_flags(res, DLM_LOCK_RES_SETREF_INPROG);
|
spin_unlock(&res->spinlock);
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/* clear our bit from the master's refmap, ignore errors */
|
ret = dlm_drop_lockres_ref(dlm, res);
|
if (ret < 0) {
|
if (!dlm_is_host_down(ret))
|
BUG();
|
}
|
spin_lock(&dlm->spinlock);
|
spin_lock(&res->spinlock);
|
}
|
|
if (!list_empty(&res->purge)) {
|
mlog(0, "%s: Removing res %.*s from purgelist, master %d\n",
|
dlm->name, res->lockname.len, res->lockname.name, master);
|
list_del_init(&res->purge);
|
dlm_lockres_put(res);
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dlm->purge_count--;
|
}
|
|
if (!master && ret == DLM_DEREF_RESPONSE_INPROG) {
|
mlog(0, "%s: deref %.*s in progress\n",
|
dlm->name, res->lockname.len, res->lockname.name);
|
spin_unlock(&res->spinlock);
|
return;
|
}
|
|
if (!__dlm_lockres_unused(res)) {
|
mlog(ML_ERROR, "%s: res %.*s in use after deref\n",
|
dlm->name, res->lockname.len, res->lockname.name);
|
__dlm_print_one_lock_resource(res);
|
BUG();
|
}
|
|
__dlm_unhash_lockres(dlm, res);
|
|
spin_lock(&dlm->track_lock);
|
if (!list_empty(&res->tracking))
|
list_del_init(&res->tracking);
|
else {
|
mlog(ML_ERROR, "Resource %.*s not on the Tracking list\n",
|
res->lockname.len, res->lockname.name);
|
__dlm_print_one_lock_resource(res);
|
}
|
spin_unlock(&dlm->track_lock);
|
|
/* lockres is not in the hash now. drop the flag and wake up
|
* any processes waiting in dlm_get_lock_resource. */
|
if (!master) {
|
res->state &= ~DLM_LOCK_RES_DROPPING_REF;
|
spin_unlock(&res->spinlock);
|
wake_up(&res->wq);
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} else
|
spin_unlock(&res->spinlock);
|
}
|
|
static void dlm_run_purge_list(struct dlm_ctxt *dlm,
|
int purge_now)
|
{
|
unsigned int run_max, unused;
|
unsigned long purge_jiffies;
|
struct dlm_lock_resource *lockres;
|
|
spin_lock(&dlm->spinlock);
|
run_max = dlm->purge_count;
|
|
while(run_max && !list_empty(&dlm->purge_list)) {
|
run_max--;
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|
lockres = list_entry(dlm->purge_list.next,
|
struct dlm_lock_resource, purge);
|
|
spin_lock(&lockres->spinlock);
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|
purge_jiffies = lockres->last_used +
|
msecs_to_jiffies(DLM_PURGE_INTERVAL_MS);
|
|
/* Make sure that we want to be processing this guy at
|
* this time. */
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if (!purge_now && time_after(purge_jiffies, jiffies)) {
|
/* Since resources are added to the purge list
|
* in tail order, we can stop at the first
|
* unpurgable resource -- anyone added after
|
* him will have a greater last_used value */
|
spin_unlock(&lockres->spinlock);
|
break;
|
}
|
|
/* Status of the lockres *might* change so double
|
* check. If the lockres is unused, holding the dlm
|
* spinlock will prevent people from getting and more
|
* refs on it. */
|
unused = __dlm_lockres_unused(lockres);
|
if (!unused ||
|
(lockres->state & DLM_LOCK_RES_MIGRATING) ||
|
(lockres->inflight_assert_workers != 0)) {
|
mlog(0, "%s: res %.*s is in use or being remastered, "
|
"used %d, state %d, assert master workers %u\n",
|
dlm->name, lockres->lockname.len,
|
lockres->lockname.name,
|
!unused, lockres->state,
|
lockres->inflight_assert_workers);
|
list_move_tail(&lockres->purge, &dlm->purge_list);
|
spin_unlock(&lockres->spinlock);
|
continue;
|
}
|
|
dlm_lockres_get(lockres);
|
|
dlm_purge_lockres(dlm, lockres);
|
|
dlm_lockres_put(lockres);
|
|
/* Avoid adding any scheduling latencies */
|
cond_resched_lock(&dlm->spinlock);
|
}
|
|
spin_unlock(&dlm->spinlock);
|
}
|
|
static void dlm_shuffle_lists(struct dlm_ctxt *dlm,
|
struct dlm_lock_resource *res)
|
{
|
struct dlm_lock *lock, *target;
|
int can_grant = 1;
|
|
/*
|
* Because this function is called with the lockres
|
* spinlock, and because we know that it is not migrating/
|
* recovering/in-progress, it is fine to reserve asts and
|
* basts right before queueing them all throughout
|
*/
|
assert_spin_locked(&dlm->ast_lock);
|
assert_spin_locked(&res->spinlock);
|
BUG_ON((res->state & (DLM_LOCK_RES_MIGRATING|
|
DLM_LOCK_RES_RECOVERING|
|
DLM_LOCK_RES_IN_PROGRESS)));
|
|
converting:
|
if (list_empty(&res->converting))
|
goto blocked;
|
mlog(0, "%s: res %.*s has locks on the convert queue\n", dlm->name,
|
res->lockname.len, res->lockname.name);
|
|
target = list_entry(res->converting.next, struct dlm_lock, list);
|
if (target->ml.convert_type == LKM_IVMODE) {
|
mlog(ML_ERROR, "%s: res %.*s converting lock to invalid mode\n",
|
dlm->name, res->lockname.len, res->lockname.name);
|
BUG();
|
}
|
list_for_each_entry(lock, &res->granted, list) {
|
if (lock==target)
|
continue;
|
if (!dlm_lock_compatible(lock->ml.type,
|
target->ml.convert_type)) {
|
can_grant = 0;
|
/* queue the BAST if not already */
|
if (lock->ml.highest_blocked == LKM_IVMODE) {
|
__dlm_lockres_reserve_ast(res);
|
__dlm_queue_bast(dlm, lock);
|
}
|
/* update the highest_blocked if needed */
|
if (lock->ml.highest_blocked < target->ml.convert_type)
|
lock->ml.highest_blocked =
|
target->ml.convert_type;
|
}
|
}
|
|
list_for_each_entry(lock, &res->converting, list) {
|
if (lock==target)
|
continue;
|
if (!dlm_lock_compatible(lock->ml.type,
|
target->ml.convert_type)) {
|
can_grant = 0;
|
if (lock->ml.highest_blocked == LKM_IVMODE) {
|
__dlm_lockres_reserve_ast(res);
|
__dlm_queue_bast(dlm, lock);
|
}
|
if (lock->ml.highest_blocked < target->ml.convert_type)
|
lock->ml.highest_blocked =
|
target->ml.convert_type;
|
}
|
}
|
|
/* we can convert the lock */
|
if (can_grant) {
|
spin_lock(&target->spinlock);
|
BUG_ON(target->ml.highest_blocked != LKM_IVMODE);
|
|
mlog(0, "%s: res %.*s, AST for Converting lock %u:%llu, type "
|
"%d => %d, node %u\n", dlm->name, res->lockname.len,
|
res->lockname.name,
|
dlm_get_lock_cookie_node(be64_to_cpu(target->ml.cookie)),
|
dlm_get_lock_cookie_seq(be64_to_cpu(target->ml.cookie)),
|
target->ml.type,
|
target->ml.convert_type, target->ml.node);
|
|
target->ml.type = target->ml.convert_type;
|
target->ml.convert_type = LKM_IVMODE;
|
list_move_tail(&target->list, &res->granted);
|
|
BUG_ON(!target->lksb);
|
target->lksb->status = DLM_NORMAL;
|
|
spin_unlock(&target->spinlock);
|
|
__dlm_lockres_reserve_ast(res);
|
__dlm_queue_ast(dlm, target);
|
/* go back and check for more */
|
goto converting;
|
}
|
|
blocked:
|
if (list_empty(&res->blocked))
|
goto leave;
|
target = list_entry(res->blocked.next, struct dlm_lock, list);
|
|
list_for_each_entry(lock, &res->granted, list) {
|
if (lock==target)
|
continue;
|
if (!dlm_lock_compatible(lock->ml.type, target->ml.type)) {
|
can_grant = 0;
|
if (lock->ml.highest_blocked == LKM_IVMODE) {
|
__dlm_lockres_reserve_ast(res);
|
__dlm_queue_bast(dlm, lock);
|
}
|
if (lock->ml.highest_blocked < target->ml.type)
|
lock->ml.highest_blocked = target->ml.type;
|
}
|
}
|
|
list_for_each_entry(lock, &res->converting, list) {
|
if (lock==target)
|
continue;
|
if (!dlm_lock_compatible(lock->ml.type, target->ml.type)) {
|
can_grant = 0;
|
if (lock->ml.highest_blocked == LKM_IVMODE) {
|
__dlm_lockres_reserve_ast(res);
|
__dlm_queue_bast(dlm, lock);
|
}
|
if (lock->ml.highest_blocked < target->ml.type)
|
lock->ml.highest_blocked = target->ml.type;
|
}
|
}
|
|
/* we can grant the blocked lock (only
|
* possible if converting list empty) */
|
if (can_grant) {
|
spin_lock(&target->spinlock);
|
BUG_ON(target->ml.highest_blocked != LKM_IVMODE);
|
|
mlog(0, "%s: res %.*s, AST for Blocked lock %u:%llu, type %d, "
|
"node %u\n", dlm->name, res->lockname.len,
|
res->lockname.name,
|
dlm_get_lock_cookie_node(be64_to_cpu(target->ml.cookie)),
|
dlm_get_lock_cookie_seq(be64_to_cpu(target->ml.cookie)),
|
target->ml.type, target->ml.node);
|
|
/* target->ml.type is already correct */
|
list_move_tail(&target->list, &res->granted);
|
|
BUG_ON(!target->lksb);
|
target->lksb->status = DLM_NORMAL;
|
|
spin_unlock(&target->spinlock);
|
|
__dlm_lockres_reserve_ast(res);
|
__dlm_queue_ast(dlm, target);
|
/* 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)
|
{
|
if (res) {
|
spin_lock(&dlm->spinlock);
|
spin_lock(&res->spinlock);
|
__dlm_dirty_lockres(dlm, res);
|
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)
|
{
|
assert_spin_locked(&dlm->spinlock);
|
assert_spin_locked(&res->spinlock);
|
|
/* don't shuffle secondary queues */
|
if (res->owner == dlm->node_num) {
|
if (res->state & (DLM_LOCK_RES_MIGRATING |
|
DLM_LOCK_RES_BLOCK_DIRTY))
|
return;
|
|
if (list_empty(&res->dirty)) {
|
/* ref for dirty_list */
|
dlm_lockres_get(res);
|
list_add_tail(&res->dirty, &dlm->dirty_list);
|
res->state |= DLM_LOCK_RES_DIRTY;
|
}
|
}
|
|
mlog(0, "%s: res %.*s\n", dlm->name, res->lockname.len,
|
res->lockname.name);
|
}
|
|
|
/* 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-%s",
|
dlm->name);
|
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, "%s: res %.*s, Flush AST for lock %u:%llu, type %d, "
|
"node %u\n", dlm->name, res->lockname.len,
|
res->lockname.name,
|
dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
|
dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
|
lock->ml.type, lock->ml.node);
|
|
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, "%s: res %.*s, AST queued while flushing last "
|
"one\n", dlm->name, res->lockname.len,
|
res->lockname.name);
|
} 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, "%s: res %.*s, Flush BAST for lock %u:%llu, "
|
"blocked %d, node %u\n",
|
dlm->name, res->lockname.len, res->lockname.name,
|
dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
|
dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
|
hi, lock->ml.node);
|
|
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, "%s: res %.*s, BAST queued while flushing last "
|
"one\n", dlm->name, res->lockname.len,
|
res->lockname.name);
|
} 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
|
|
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);
|
/* We clear the DLM_LOCK_RES_DIRTY state once we shuffle lists below */
|
list_del_init(&res->dirty);
|
spin_unlock(&res->spinlock);
|
spin_unlock(&dlm->spinlock);
|
/* Drop dirty_list ref */
|
dlm_lockres_put(res);
|
|
/* lockres can be re-dirtied/re-added to the
|
* dirty_list in this gap, but that is ok */
|
|
spin_lock(&dlm->ast_lock);
|
spin_lock(&res->spinlock);
|
if (res->owner != dlm->node_num) {
|
__dlm_print_one_lock_resource(res);
|
mlog(ML_ERROR, "%s: inprog %d, mig %d, reco %d,"
|
" dirty %d\n", dlm->name,
|
!!(res->state & DLM_LOCK_RES_IN_PROGRESS),
|
!!(res->state & DLM_LOCK_RES_MIGRATING),
|
!!(res->state & DLM_LOCK_RES_RECOVERING),
|
!!(res->state & DLM_LOCK_RES_DIRTY));
|
}
|
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. */
|
BUG_ON(res->state & DLM_LOCK_RES_MIGRATING);
|
if (res->state & (DLM_LOCK_RES_IN_PROGRESS |
|
DLM_LOCK_RES_RECOVERING |
|
DLM_LOCK_RES_RECOVERY_WAITING)) {
|
/* move it to the tail and keep going */
|
res->state &= ~DLM_LOCK_RES_DIRTY;
|
spin_unlock(&res->spinlock);
|
spin_unlock(&dlm->ast_lock);
|
mlog(0, "%s: res %.*s, inprogress, delay list "
|
"shuffle, state %d\n", dlm->name,
|
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. */
|
|
/* called while holding lockres lock */
|
dlm_shuffle_lists(dlm, res);
|
res->state &= ~DLM_LOCK_RES_DIRTY;
|
spin_unlock(&res->spinlock);
|
spin_unlock(&dlm->ast_lock);
|
|
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);
|
__dlm_dirty_lockres(dlm, res);
|
spin_unlock(&res->spinlock);
|
}
|
dlm_lockres_put(res);
|
|
/* unlikely, but we may need to give time to
|
* other tasks */
|
if (!--n) {
|
mlog(0, "%s: Throttling dlm thread\n",
|
dlm->name);
|
break;
|
}
|
}
|
|
spin_unlock(&dlm->spinlock);
|
dlm_flush_asts(dlm);
|
|
/* yield and continue right away if there is more work to do */
|
if (!n) {
|
cond_resched();
|
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;
|
}
|
