From: Trond Myklebust <trond.myklebust@primarydata.com>
To: linux-nfs@vger.kernel.org
Subject: [PATCH 4/5] SUNRPC: Reduce latency when send queue is congested
Date: Tue, 14 Jun 2016 15:04:05 -0400 [thread overview]
Message-ID: <1465931046-30696-4-git-send-email-trond.myklebust@primarydata.com> (raw)
In-Reply-To: <1465931046-30696-3-git-send-email-trond.myklebust@primarydata.com>
Use the low latency transport workqueue to process the task that is
next in line on the xprt->sending queue.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
---
include/linux/sunrpc/sched.h | 4 ++++
net/sunrpc/sched.c | 43 +++++++++++++++++++++++++++++++++----------
net/sunrpc/xprt.c | 6 ++++--
3 files changed, 41 insertions(+), 12 deletions(-)
diff --git a/include/linux/sunrpc/sched.h b/include/linux/sunrpc/sched.h
index ef780b3b5e31..817af0b4385e 100644
--- a/include/linux/sunrpc/sched.h
+++ b/include/linux/sunrpc/sched.h
@@ -230,6 +230,10 @@ void rpc_wake_up_queued_task(struct rpc_wait_queue *,
struct rpc_task *);
void rpc_wake_up(struct rpc_wait_queue *);
struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *);
+struct rpc_task *rpc_wake_up_first_on_wq(struct workqueue_struct *wq,
+ struct rpc_wait_queue *,
+ bool (*)(struct rpc_task *, void *),
+ void *);
struct rpc_task *rpc_wake_up_first(struct rpc_wait_queue *,
bool (*)(struct rpc_task *, void *),
void *);
diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c
index a9f786247ffb..9ae588511aaf 100644
--- a/net/sunrpc/sched.c
+++ b/net/sunrpc/sched.c
@@ -330,7 +330,8 @@ EXPORT_SYMBOL_GPL(__rpc_wait_for_completion_task);
* lockless RPC_IS_QUEUED() test) before we've had a chance to test
* the RPC_TASK_RUNNING flag.
*/
-static void rpc_make_runnable(struct rpc_task *task)
+static void rpc_make_runnable(struct workqueue_struct *wq,
+ struct rpc_task *task)
{
bool need_wakeup = !rpc_test_and_set_running(task);
@@ -339,7 +340,7 @@ static void rpc_make_runnable(struct rpc_task *task)
return;
if (RPC_IS_ASYNC(task)) {
INIT_WORK(&task->u.tk_work, rpc_async_schedule);
- queue_work(rpciod_workqueue, &task->u.tk_work);
+ queue_work(wq, &task->u.tk_work);
} else
wake_up_bit(&task->tk_runstate, RPC_TASK_QUEUED);
}
@@ -408,13 +409,16 @@ void rpc_sleep_on_priority(struct rpc_wait_queue *q, struct rpc_task *task,
EXPORT_SYMBOL_GPL(rpc_sleep_on_priority);
/**
- * __rpc_do_wake_up_task - wake up a single rpc_task
+ * __rpc_do_wake_up_task_on_wq - wake up a single rpc_task
+ * @wq: workqueue on which to run task
* @queue: wait queue
* @task: task to be woken up
*
* Caller must hold queue->lock, and have cleared the task queued flag.
*/
-static void __rpc_do_wake_up_task(struct rpc_wait_queue *queue, struct rpc_task *task)
+static void __rpc_do_wake_up_task_on_wq(struct workqueue_struct *wq,
+ struct rpc_wait_queue *queue,
+ struct rpc_task *task)
{
dprintk("RPC: %5u __rpc_wake_up_task (now %lu)\n",
task->tk_pid, jiffies);
@@ -429,7 +433,7 @@ static void __rpc_do_wake_up_task(struct rpc_wait_queue *queue, struct rpc_task
__rpc_remove_wait_queue(queue, task);
- rpc_make_runnable(task);
+ rpc_make_runnable(wq, task);
dprintk("RPC: __rpc_wake_up_task done\n");
}
@@ -437,16 +441,25 @@ static void __rpc_do_wake_up_task(struct rpc_wait_queue *queue, struct rpc_task
/*
* Wake up a queued task while the queue lock is being held
*/
-static void rpc_wake_up_task_queue_locked(struct rpc_wait_queue *queue, struct rpc_task *task)
+static void rpc_wake_up_task_on_wq_queue_locked(struct workqueue_struct *wq,
+ struct rpc_wait_queue *queue, struct rpc_task *task)
{
if (RPC_IS_QUEUED(task)) {
smp_rmb();
if (task->tk_waitqueue == queue)
- __rpc_do_wake_up_task(queue, task);
+ __rpc_do_wake_up_task_on_wq(wq, queue, task);
}
}
/*
+ * Wake up a queued task while the queue lock is being held
+ */
+static void rpc_wake_up_task_queue_locked(struct rpc_wait_queue *queue, struct rpc_task *task)
+{
+ rpc_wake_up_task_on_wq_queue_locked(rpciod_workqueue, queue, task);
+}
+
+/*
* Wake up a task on a specific queue
*/
void rpc_wake_up_queued_task(struct rpc_wait_queue *queue, struct rpc_task *task)
@@ -519,7 +532,8 @@ static struct rpc_task *__rpc_find_next_queued(struct rpc_wait_queue *queue)
/*
* Wake up the first task on the wait queue.
*/
-struct rpc_task *rpc_wake_up_first(struct rpc_wait_queue *queue,
+struct rpc_task *rpc_wake_up_first_on_wq(struct workqueue_struct *wq,
+ struct rpc_wait_queue *queue,
bool (*func)(struct rpc_task *, void *), void *data)
{
struct rpc_task *task = NULL;
@@ -530,7 +544,7 @@ struct rpc_task *rpc_wake_up_first(struct rpc_wait_queue *queue,
task = __rpc_find_next_queued(queue);
if (task != NULL) {
if (func(task, data))
- rpc_wake_up_task_queue_locked(queue, task);
+ rpc_wake_up_task_on_wq_queue_locked(wq, queue, task);
else
task = NULL;
}
@@ -538,6 +552,15 @@ struct rpc_task *rpc_wake_up_first(struct rpc_wait_queue *queue,
return task;
}
+
+/*
+ * Wake up the first task on the wait queue.
+ */
+struct rpc_task *rpc_wake_up_first(struct rpc_wait_queue *queue,
+ bool (*func)(struct rpc_task *, void *), void *data)
+{
+ return rpc_wake_up_first_on_wq(rpciod_workqueue, queue, func, data);
+}
EXPORT_SYMBOL_GPL(rpc_wake_up_first);
static bool rpc_wake_up_next_func(struct rpc_task *task, void *data)
@@ -815,7 +838,7 @@ void rpc_execute(struct rpc_task *task)
bool is_async = RPC_IS_ASYNC(task);
rpc_set_active(task);
- rpc_make_runnable(task);
+ rpc_make_runnable(rpciod_workqueue, task);
if (!is_async)
__rpc_execute(task);
}
diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c
index 71df082b84a9..8313960cac52 100644
--- a/net/sunrpc/xprt.c
+++ b/net/sunrpc/xprt.c
@@ -295,7 +295,8 @@ static void __xprt_lock_write_next(struct rpc_xprt *xprt)
if (test_and_set_bit(XPRT_LOCKED, &xprt->state))
return;
- if (rpc_wake_up_first(&xprt->sending, __xprt_lock_write_func, xprt))
+ if (rpc_wake_up_first_on_wq(xprtiod_workqueue, &xprt->sending,
+ __xprt_lock_write_func, xprt))
return;
xprt_clear_locked(xprt);
}
@@ -324,7 +325,8 @@ static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt)
return;
if (RPCXPRT_CONGESTED(xprt))
goto out_unlock;
- if (rpc_wake_up_first(&xprt->sending, __xprt_lock_write_cong_func, xprt))
+ if (rpc_wake_up_first_on_wq(xprtiod_workqueue, &xprt->sending,
+ __xprt_lock_write_cong_func, xprt))
return;
out_unlock:
xprt_clear_locked(xprt);
--
2.5.5
next prev parent reply other threads:[~2016-06-14 19:04 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-06-14 19:04 [PATCH 1/5] SUNRPC: Small optimisation of client receive Trond Myklebust
2016-06-14 19:04 ` [PATCH 2/5] SUNRPC: Consolidate xs_tcp_data_ready and xs_data_ready Trond Myklebust
2016-06-14 19:04 ` [PATCH 3/5] SUNRPC: RPC transport queue must be low latency Trond Myklebust
2016-06-14 19:04 ` Trond Myklebust [this message]
2016-06-14 19:04 ` [PATCH 5/5] SUNRPC: Fix suspicious enobufs issues Trond Myklebust
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