summaryrefslogtreecommitdiffstats
path: root/net/sunrpc
diff options
context:
space:
mode:
authorTrond Myklebust <trond.myklebust@hammerspace.com>2019-05-01 10:49:27 -0400
committerTrond Myklebust <trond.myklebust@hammerspace.com>2019-07-06 14:54:48 -0400
commit7e0a0e38fcfea47e74b0ff6da6266f00bcd2af43 (patch)
tree7128a333d8563e59c542b7a7725c7bf0928080b8 /net/sunrpc
parent44942b4e457beda00981f616402a1a791e8c616e (diff)
downloadlinux-7e0a0e38fcfea47e74b0ff6da6266f00bcd2af43.tar.gz
linux-7e0a0e38fcfea47e74b0ff6da6266f00bcd2af43.tar.bz2
linux-7e0a0e38fcfea47e74b0ff6da6266f00bcd2af43.zip
SUNRPC: Replace the queue timer with a delayed work function
The queue timer function, which walks the RPC queue in order to locate candidates for waking up is one of the current constraints against removing the bh-safe queue spin locks. Replace it with a delayed work queue, so that we can do the actual rpc task wake ups from an ordinary process context. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Diffstat (limited to 'net/sunrpc')
-rw-r--r--net/sunrpc/sched.c30
1 files changed, 20 insertions, 10 deletions
diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c
index a2c114812717..e0a0cf381eba 100644
--- a/net/sunrpc/sched.c
+++ b/net/sunrpc/sched.c
@@ -46,7 +46,7 @@ static mempool_t *rpc_buffer_mempool __read_mostly;
static void rpc_async_schedule(struct work_struct *);
static void rpc_release_task(struct rpc_task *task);
-static void __rpc_queue_timer_fn(struct timer_list *t);
+static void __rpc_queue_timer_fn(struct work_struct *);
/*
* RPC tasks sit here while waiting for conditions to improve.
@@ -87,13 +87,19 @@ __rpc_disable_timer(struct rpc_wait_queue *queue, struct rpc_task *task)
task->tk_timeout = 0;
list_del(&task->u.tk_wait.timer_list);
if (list_empty(&queue->timer_list.list))
- del_timer(&queue->timer_list.timer);
+ cancel_delayed_work(&queue->timer_list.dwork);
}
static void
rpc_set_queue_timer(struct rpc_wait_queue *queue, unsigned long expires)
{
- timer_reduce(&queue->timer_list.timer, expires);
+ unsigned long now = jiffies;
+ queue->timer_list.expires = expires;
+ if (time_before_eq(expires, now))
+ expires = 0;
+ else
+ expires -= now;
+ mod_delayed_work(rpciod_workqueue, &queue->timer_list.dwork, expires);
}
/*
@@ -107,7 +113,8 @@ __rpc_add_timer(struct rpc_wait_queue *queue, struct rpc_task *task,
task->tk_pid, jiffies_to_msecs(timeout - jiffies));
task->tk_timeout = timeout;
- rpc_set_queue_timer(queue, timeout);
+ if (list_empty(&queue->timer_list.list) || time_before(timeout, queue->timer_list.expires))
+ rpc_set_queue_timer(queue, timeout);
list_add(&task->u.tk_wait.timer_list, &queue->timer_list.list);
}
@@ -250,7 +257,8 @@ static void __rpc_init_priority_wait_queue(struct rpc_wait_queue *queue, const c
queue->maxpriority = nr_queues - 1;
rpc_reset_waitqueue_priority(queue);
queue->qlen = 0;
- timer_setup(&queue->timer_list.timer, __rpc_queue_timer_fn, 0);
+ queue->timer_list.expires = 0;
+ INIT_DEFERRABLE_WORK(&queue->timer_list.dwork, __rpc_queue_timer_fn);
INIT_LIST_HEAD(&queue->timer_list.list);
rpc_assign_waitqueue_name(queue, qname);
}
@@ -269,7 +277,7 @@ EXPORT_SYMBOL_GPL(rpc_init_wait_queue);
void rpc_destroy_wait_queue(struct rpc_wait_queue *queue)
{
- del_timer_sync(&queue->timer_list.timer);
+ cancel_delayed_work_sync(&queue->timer_list.dwork);
}
EXPORT_SYMBOL_GPL(rpc_destroy_wait_queue);
@@ -759,13 +767,15 @@ void rpc_wake_up_status(struct rpc_wait_queue *queue, int status)
}
EXPORT_SYMBOL_GPL(rpc_wake_up_status);
-static void __rpc_queue_timer_fn(struct timer_list *t)
+static void __rpc_queue_timer_fn(struct work_struct *work)
{
- struct rpc_wait_queue *queue = from_timer(queue, t, timer_list.timer);
+ struct rpc_wait_queue *queue = container_of(work,
+ struct rpc_wait_queue,
+ timer_list.dwork.work);
struct rpc_task *task, *n;
unsigned long expires, now, timeo;
- spin_lock(&queue->lock);
+ spin_lock_bh(&queue->lock);
expires = now = jiffies;
list_for_each_entry_safe(task, n, &queue->timer_list.list, u.tk_wait.timer_list) {
timeo = task->tk_timeout;
@@ -780,7 +790,7 @@ static void __rpc_queue_timer_fn(struct timer_list *t)
}
if (!list_empty(&queue->timer_list.list))
rpc_set_queue_timer(queue, expires);
- spin_unlock(&queue->lock);
+ spin_unlock_bh(&queue->lock);
}
static void __rpc_atrun(struct rpc_task *task)