Commit 35525b79 authored by Andriy Skulysh's avatar Andriy Skulysh Committed by J. Bruce Fields
Browse files

sunrpc: Fix lockd sleeping until timeout 



There is a race in enqueueing thread to a pool and
waking up a thread.
lockd doesn't wake up on reception of lock granted callback
if svc_wake_up() is called before lockd's thread is added
to a pool.

Signed-off-by: default avatarAndriy Skulysh <Andriy_Skulysh@xyratex.com>
Signed-off-by: default avatarJ. Bruce Fields <bfields@redhat.com>
parent 624ab464

include/linux/sunrpc/svc.h

+1 −0
Original line number Diff line number Diff line
@@ -50,6 +50,7 @@ struct svc_pool { 
	unsigned int		sp_nrthreads;	/* # of threads in pool */

	struct list_head	sp_all_threads;	/* all server threads */

	struct svc_pool_stats	sp_stats;	/* statistics on pool operation */

	int			sp_task_pending;/* has pending task */

} ____cacheline_aligned_in_smp;



/*

net/sunrpc/svc_xprt.c

+8 −1
Original line number Diff line number Diff line
@@ -499,7 +499,8 @@ void svc_wake_up(struct svc_serv *serv) 
			rqstp->rq_xprt = NULL;

			 */

			wake_up(&rqstp->rq_wait);

		}

		} else

			pool->sp_task_pending = 1;

		spin_unlock_bh(&pool->sp_lock);

	}

}
@@ -634,7 +635,13 @@ struct svc_xprt *svc_get_next_xprt(struct svc_rqst *rqstp, long timeout) 
		 * long for cache updates.

		 */

		rqstp->rq_chandle.thread_wait = 1*HZ;

		pool->sp_task_pending = 0;

	} else {

		if (pool->sp_task_pending) {

			pool->sp_task_pending = 0;

			spin_unlock_bh(&pool->sp_lock);

			return ERR_PTR(-EAGAIN);

		}

		/* No data pending. Go to sleep */

		svc_thread_enqueue(pool, rqstp);

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