Commit c91664c8 authored by NeilBrown's avatar NeilBrown Committed by Greg Kroah-Hartman

staging: lustre: ldlm: use delayed_work for pools_recalc

ldlm currenty has a kthread which wakes up every so often
and calls ldlm_pools_recalc().
The thread is started and stopped, but no other external interactions
happen.

This can trivially be replaced by a delayed_work if we have
ldlm_pools_recalc() reschedule the work rather than just report
when to do that.
Signed-off-by: default avatarNeilBrown <neilb@suse.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 1a6cc3b1
......@@ -784,9 +784,6 @@ static int ldlm_pool_granted(struct ldlm_pool *pl)
return atomic_read(&pl->pl_granted);
}
static struct ptlrpc_thread *ldlm_pools_thread;
static struct completion ldlm_pools_comp;
/*
* count locks from all namespaces (if possible). Returns number of
* cached locks.
......@@ -899,8 +896,12 @@ static unsigned long ldlm_pools_cli_scan(struct shrinker *s,
sc->gfp_mask);
}
static int ldlm_pools_recalc(enum ldlm_side client)
static void ldlm_pools_recalc(struct work_struct *ws);
static DECLARE_DELAYED_WORK(ldlm_recalc_pools, ldlm_pools_recalc);
static void ldlm_pools_recalc(struct work_struct *ws)
{
enum ldlm_side client = LDLM_NAMESPACE_CLIENT;
struct ldlm_namespace *ns;
struct ldlm_namespace *ns_old = NULL;
/* seconds of sleep if no active namespaces */
......@@ -982,92 +983,19 @@ static int ldlm_pools_recalc(enum ldlm_side client)
/* Wake up the blocking threads from time to time. */
ldlm_bl_thread_wakeup();
return time;
}
static int ldlm_pools_thread_main(void *arg)
{
struct ptlrpc_thread *thread = (struct ptlrpc_thread *)arg;
int c_time;
thread_set_flags(thread, SVC_RUNNING);
wake_up(&thread->t_ctl_waitq);
CDEBUG(D_DLMTRACE, "%s: pool thread starting, process %d\n",
"ldlm_poold", current_pid());
while (1) {
/*
* Recal all pools on this tick.
*/
c_time = ldlm_pools_recalc(LDLM_NAMESPACE_CLIENT);
/*
* Wait until the next check time, or until we're
* stopped.
*/
wait_event_idle_timeout(thread->t_ctl_waitq,
thread_is_stopping(thread) ||
thread_is_event(thread),
c_time * HZ);
if (thread_test_and_clear_flags(thread, SVC_STOPPING))
break;
thread_test_and_clear_flags(thread, SVC_EVENT);
}
thread_set_flags(thread, SVC_STOPPED);
wake_up(&thread->t_ctl_waitq);
CDEBUG(D_DLMTRACE, "%s: pool thread exiting, process %d\n",
"ldlm_poold", current_pid());
complete_and_exit(&ldlm_pools_comp, 0);
schedule_delayed_work(&ldlm_recalc_pools, time * HZ);
}
static int ldlm_pools_thread_start(void)
{
struct task_struct *task;
if (ldlm_pools_thread)
return -EALREADY;
ldlm_pools_thread = kzalloc(sizeof(*ldlm_pools_thread), GFP_NOFS);
if (!ldlm_pools_thread)
return -ENOMEM;
init_completion(&ldlm_pools_comp);
init_waitqueue_head(&ldlm_pools_thread->t_ctl_waitq);
schedule_delayed_work(&ldlm_recalc_pools, 0);
task = kthread_run(ldlm_pools_thread_main, ldlm_pools_thread,
"ldlm_poold");
if (IS_ERR(task)) {
CERROR("Can't start pool thread, error %ld\n", PTR_ERR(task));
kfree(ldlm_pools_thread);
ldlm_pools_thread = NULL;
return PTR_ERR(task);
}
wait_event_idle(ldlm_pools_thread->t_ctl_waitq,
thread_is_running(ldlm_pools_thread));
return 0;
}
static void ldlm_pools_thread_stop(void)
{
if (!ldlm_pools_thread)
return;
thread_set_flags(ldlm_pools_thread, SVC_STOPPING);
wake_up(&ldlm_pools_thread->t_ctl_waitq);
/*
* Make sure that pools thread is finished before freeing @thread.
* This fixes possible race and oops due to accessing freed memory
* in pools thread.
*/
wait_for_completion(&ldlm_pools_comp);
kfree(ldlm_pools_thread);
ldlm_pools_thread = NULL;
cancel_delayed_work_sync(&ldlm_recalc_pools);
}
static struct shrinker ldlm_pools_cli_shrinker = {
......@@ -1081,20 +1009,15 @@ int ldlm_pools_init(void)
int rc;
rc = ldlm_pools_thread_start();
if (rc)
return rc;
rc = register_shrinker(&ldlm_pools_cli_shrinker);
if (rc)
ldlm_pools_thread_stop();
if (!rc)
rc = register_shrinker(&ldlm_pools_cli_shrinker);
return rc;
}
void ldlm_pools_fini(void)
{
if (ldlm_pools_thread)
unregister_shrinker(&ldlm_pools_cli_shrinker);
unregister_shrinker(&ldlm_pools_cli_shrinker);
ldlm_pools_thread_stop();
}
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment