From ceff739c53a1734d820d013d7d98f932994674d2 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Wed, 19 Nov 2014 07:51:21 -0500 Subject: sunrpc: have svc_wake_up only deal with pool 0 The way that svc_wake_up works is a bit inefficient. It walks all of the available pools for a service and either wakes up a task in each one or sets the SP_TASK_PENDING flag in each one. When svc_wake_up is called, there is no need to wake up more than one thread to do this work. In practice, only lockd currently uses this function and it's single threaded anyway. Thus, this just boils down to doing a wake up of a thread in pool 0 or setting a single flag. Eliminate the for loop in this function and change it to just operate on pool 0. Also update the comments that sit above it and get rid of some code that has been commented out for years now. Signed-off-by: Jeff Layton Signed-off-by: J. Bruce Fields --- net/sunrpc/svc_xprt.c | 37 ++++++++++++++++--------------------- 1 file changed, 16 insertions(+), 21 deletions(-) diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c index 37446046f4bf..b2676e597fc4 100644 --- a/net/sunrpc/svc_xprt.c +++ b/net/sunrpc/svc_xprt.c @@ -484,34 +484,29 @@ static void svc_xprt_release(struct svc_rqst *rqstp) } /* - * External function to wake up a server waiting for data - * This really only makes sense for services like lockd - * which have exactly one thread anyway. + * Some svc_serv's will have occasional work to do, even when a xprt is not + * waiting to be serviced. This function is there to "kick" a task in one of + * those services so that it can wake up and do that work. Note that we only + * bother with pool 0 as we don't need to wake up more than one thread for + * this purpose. */ void svc_wake_up(struct svc_serv *serv) { struct svc_rqst *rqstp; - unsigned int i; struct svc_pool *pool; - for (i = 0; i < serv->sv_nrpools; i++) { - pool = &serv->sv_pools[i]; + pool = &serv->sv_pools[0]; - spin_lock_bh(&pool->sp_lock); - if (!list_empty(&pool->sp_threads)) { - rqstp = list_entry(pool->sp_threads.next, - struct svc_rqst, - rq_list); - dprintk("svc: daemon %p woken up.\n", rqstp); - /* - svc_thread_dequeue(pool, rqstp); - rqstp->rq_xprt = NULL; - */ - wake_up_process(rqstp->rq_task); - } else - set_bit(SP_TASK_PENDING, &pool->sp_flags); - spin_unlock_bh(&pool->sp_lock); - } + spin_lock_bh(&pool->sp_lock); + if (!list_empty(&pool->sp_threads)) { + rqstp = list_entry(pool->sp_threads.next, + struct svc_rqst, + rq_list); + dprintk("svc: daemon %p woken up.\n", rqstp); + wake_up_process(rqstp->rq_task); + } else + set_bit(SP_TASK_PENDING, &pool->sp_flags); + spin_unlock_bh(&pool->sp_lock); } EXPORT_SYMBOL_GPL(svc_wake_up); -- cgit v1.2.3