2008-02-19 23:15:05

by Myklebust, Trond

[permalink] [raw]
Subject: [PATCH 2/4] SUNRPC: Allow the rpc_release() callback to be run on another workqueue

A lot of the work done by the rpc_release() callback is inappropriate for
rpciod as it will often involve things like starting a new rpc call in
order to clean up state after an interrupted NFSv4 open() call, or
calls to mntput(), etc.

This patch allows the caller of rpc_run_task() to specify that the
rpc_release callback should run on a different workqueue than the default
rpciod_workqueue.

Signed-off-by: Trond Myklebust <[email protected]>
---

include/linux/sunrpc/sched.h | 1 +
net/sunrpc/sched.c | 29 +++++++++++++++++++++--------
2 files changed, 22 insertions(+), 8 deletions(-)

diff --git a/include/linux/sunrpc/sched.h b/include/linux/sunrpc/sched.h
index f689f02..fefb0ab 100644
--- a/include/linux/sunrpc/sched.h
+++ b/include/linux/sunrpc/sched.h
@@ -123,6 +123,7 @@ struct rpc_task_setup {
const struct rpc_message *rpc_message;
const struct rpc_call_ops *callback_ops;
void *callback_data;
+ struct workqueue_struct *workqueue;
unsigned short flags;
signed char priority;
};
diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c
index 4c66912..3e0b223 100644
--- a/net/sunrpc/sched.c
+++ b/net/sunrpc/sched.c
@@ -326,7 +326,7 @@ static void rpc_make_runnable(struct rpc_task *task)
int status;

INIT_WORK(&task->u.tk_work, rpc_async_schedule);
- status = queue_work(task->tk_workqueue, &task->u.tk_work);
+ status = queue_work(rpciod_workqueue, &task->u.tk_work);
if (status < 0) {
printk(KERN_WARNING "RPC: failed to add task to queue: error: %d!\n", status);
task->tk_status = status;
@@ -832,7 +832,7 @@ static void rpc_init_task(struct rpc_task *task, const struct rpc_task_setup *ta
task->tk_owner = current->tgid;

/* Initialize workqueue for async tasks */
- task->tk_workqueue = rpciod_workqueue;
+ task->tk_workqueue = task_setup_data->workqueue;

task->tk_client = task_setup_data->rpc_client;
if (task->tk_client != NULL) {
@@ -868,7 +868,7 @@ rpc_alloc_task(void)
return (struct rpc_task *)mempool_alloc(rpc_task_mempool, GFP_NOFS);
}

-static void rpc_free_task(struct rcu_head *rcu)
+static void rpc_free_task_rcu(struct rcu_head *rcu)
{
struct rpc_task *task = container_of(rcu, struct rpc_task, u.tk_rcu);
dprintk("RPC: %5u freeing task\n", task->tk_pid);
@@ -898,12 +898,23 @@ out:
return task;
}

-
-void rpc_put_task(struct rpc_task *task)
+static void rpc_free_task(struct rpc_task *task)
{
const struct rpc_call_ops *tk_ops = task->tk_ops;
void *calldata = task->tk_calldata;

+ if (task->tk_flags & RPC_TASK_DYNAMIC)
+ call_rcu_bh(&task->u.tk_rcu, rpc_free_task_rcu);
+ rpc_release_calldata(tk_ops, calldata);
+}
+
+static void rpc_async_release(struct work_struct *work)
+{
+ rpc_free_task(container_of(work, struct rpc_task, u.tk_work));
+}
+
+void rpc_put_task(struct rpc_task *task)
+{
if (!atomic_dec_and_test(&task->tk_count))
return;
/* Release resources */
@@ -915,9 +926,11 @@ void rpc_put_task(struct rpc_task *task)
rpc_release_client(task->tk_client);
task->tk_client = NULL;
}
- if (task->tk_flags & RPC_TASK_DYNAMIC)
- call_rcu_bh(&task->u.tk_rcu, rpc_free_task);
- rpc_release_calldata(tk_ops, calldata);
+ if (task->tk_workqueue != NULL) {
+ INIT_WORK(&task->u.tk_work, rpc_async_release);
+ queue_work(task->tk_workqueue, &task->u.tk_work);
+ } else
+ rpc_free_task(task);
}
EXPORT_SYMBOL_GPL(rpc_put_task);