From 6797fa5a018ff916a071c6265fbf043644abcd29 Mon Sep 17 00:00:00 2001 From: "J. Bruce Fields" Date: Sat, 18 Aug 2012 15:33:51 -0400 Subject: [PATCH] svcrpc: break up svc_recv Matter of taste, I suppose, but svc_recv breaks up naturally into: allocate pages and setup arg dequeue (wait for, if necessary) next socket do something with that socket And I find it easier to read when it doesn't go on for pages and pages. Signed-off-by: J. Bruce Fields --- net/sunrpc/svc_xprt.c | 103 +++++++++++++++++++++++++++--------------- 1 file changed, 67 insertions(+), 36 deletions(-) diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c index 295e6ed21ca0..6ebc9a95bbab 100644 --- a/net/sunrpc/svc_xprt.c +++ b/net/sunrpc/svc_xprt.c @@ -568,33 +568,12 @@ static void svc_check_conn_limits(struct svc_serv *serv) } } -/* - * Receive the next request on any transport. This code is carefully - * organised not to touch any cachelines in the shared svc_serv - * structure, only cachelines in the local svc_pool. - */ -int svc_recv(struct svc_rqst *rqstp, long timeout) +int svc_alloc_arg(struct svc_rqst *rqstp) { - struct svc_xprt *xprt = NULL; - struct svc_serv *serv = rqstp->rq_server; - struct svc_pool *pool = rqstp->rq_pool; - int len, i; - int pages; - struct xdr_buf *arg; - DECLARE_WAITQUEUE(wait, current); - long time_left; - - dprintk("svc: server %p waiting for data (to = %ld)\n", - rqstp, timeout); - - if (rqstp->rq_xprt) - printk(KERN_ERR - "svc_recv: service %p, transport not NULL!\n", - rqstp); - if (waitqueue_active(&rqstp->rq_wait)) - printk(KERN_ERR - "svc_recv: service %p, wait queue active!\n", - rqstp); + struct svc_serv *serv = rqstp->rq_server; + struct xdr_buf *arg; + int pages; + int i; /* now allocate needed pages. If we get a failure, sleep briefly */ pages = (serv->sv_max_mesg + PAGE_SIZE) / PAGE_SIZE; @@ -624,11 +603,15 @@ int svc_recv(struct svc_rqst *rqstp, long timeout) arg->page_len = (pages-2)*PAGE_SIZE; arg->len = (pages-1)*PAGE_SIZE; arg->tail[0].iov_len = 0; + return 0; +} - try_to_freeze(); - cond_resched(); - if (signalled() || kthread_should_stop()) - return -EINTR; +struct svc_xprt *svc_get_next_xprt(struct svc_rqst *rqstp, long timeout) +{ + struct svc_xprt *xprt; + struct svc_pool *pool = rqstp->rq_pool; + DECLARE_WAITQUEUE(wait, current); + long time_left; /* Normally we will wait up to 5 seconds for any required * cache information to be provided. @@ -666,7 +649,7 @@ int svc_recv(struct svc_rqst *rqstp, long timeout) if (kthread_should_stop()) { set_current_state(TASK_RUNNING); spin_unlock_bh(&pool->sp_lock); - return -EINTR; + return ERR_PTR(-EINTR); } add_wait_queue(&rqstp->rq_wait, &wait); @@ -687,19 +670,25 @@ int svc_recv(struct svc_rqst *rqstp, long timeout) spin_unlock_bh(&pool->sp_lock); dprintk("svc: server %p, no data yet\n", rqstp); if (signalled() || kthread_should_stop()) - return -EINTR; + return ERR_PTR(-EINTR); else - return -EAGAIN; + return ERR_PTR(-EAGAIN); } } spin_unlock_bh(&pool->sp_lock); + return xprt; +} + +static int svc_handle_xprt(struct svc_rqst *rqstp, struct svc_xprt *xprt) +{ + struct svc_serv *serv = rqstp->rq_server; + int len = 0; - len = 0; if (test_bit(XPT_CLOSE, &xprt->xpt_flags)) { dprintk("svc_recv: found XPT_CLOSE\n"); svc_delete_xprt(xprt); /* Leave XPT_BUSY set on the dead xprt: */ - goto out; + return 0; } if (test_bit(XPT_LISTENER, &xprt->xpt_flags)) { struct svc_xprt *newxpt; @@ -727,8 +716,9 @@ int svc_recv(struct svc_rqst *rqstp, long timeout) svc_xprt_received(newxpt); } } else if (xprt->xpt_ops->xpo_has_wspace(xprt)) { + /* XPT_DATA|XPT_DEFERRED case: */ dprintk("svc: server %p, pool %u, transport %p, inuse=%d\n", - rqstp, pool->sp_id, xprt, + rqstp, rqstp->rq_pool->sp_id, xprt, atomic_read(&xprt->xpt_ref.refcount)); rqstp->rq_deferred = svc_deferred_dequeue(xprt); if (rqstp->rq_deferred) @@ -739,7 +729,48 @@ int svc_recv(struct svc_rqst *rqstp, long timeout) rqstp->rq_reserved = serv->sv_max_mesg; atomic_add(rqstp->rq_reserved, &xprt->xpt_reserved); } + /* clear XPT_BUSY: */ svc_xprt_received(xprt); + return len; +} + +/* + * Receive the next request on any transport. This code is carefully + * organised not to touch any cachelines in the shared svc_serv + * structure, only cachelines in the local svc_pool. + */ +int svc_recv(struct svc_rqst *rqstp, long timeout) +{ + struct svc_xprt *xprt = NULL; + struct svc_serv *serv = rqstp->rq_server; + int len, err; + + dprintk("svc: server %p waiting for data (to = %ld)\n", + rqstp, timeout); + + if (rqstp->rq_xprt) + printk(KERN_ERR + "svc_recv: service %p, transport not NULL!\n", + rqstp); + if (waitqueue_active(&rqstp->rq_wait)) + printk(KERN_ERR + "svc_recv: service %p, wait queue active!\n", + rqstp); + + err = svc_alloc_arg(rqstp); + if (err) + return err; + + try_to_freeze(); + cond_resched(); + if (signalled() || kthread_should_stop()) + return -EINTR; + + xprt = svc_get_next_xprt(rqstp, timeout); + if (IS_ERR(xprt)) + return PTR_ERR(xprt); + + len = svc_handle_xprt(rqstp, xprt); /* No data, incomplete (TCP) read, or accept() */ if (len <= 0)