Commit 9a0e6acc authored by NeilBrown's avatar NeilBrown Committed by Chuck Lever
Browse files

SUNRPC: use lwq for sp_sockets - renamed to sp_xprts 



lwq avoids using back pointers in lists, and uses less locking.
This introduces a new spinlock, but the other one will be removed in a
future patch.

For svc_clean_up_xprts(), we now dequeue the entire queue, walk it to
remove and process the xprts that need cleaning up, then re-enqueue the
remaining queue.

Signed-off-by: default avatarNeilBrown <neilb@suse.de>
Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
parent 5b80147e

include/linux/sunrpc/svc.h

+2 −1
Original line number Diff line number Diff line
@@ -17,6 +17,7 @@ 
#include <linux/sunrpc/xdr.h>

#include <linux/sunrpc/auth.h>

#include <linux/sunrpc/svcauth.h>

#include <linux/lwq.h>

#include <linux/wait.h>

#include <linux/mm.h>

#include <linux/pagevec.h>
@@ -34,7 +35,7 @@ 
struct svc_pool {

	unsigned int		sp_id;	    	/* pool id; also node id on NUMA */

	spinlock_t		sp_lock;	/* protects all fields */

	struct list_head	sp_sockets;	/* pending sockets */

	struct lwq		sp_xprts;	/* pending transports */

	unsigned int		sp_nrthreads;	/* # of threads in pool */

	struct list_head	sp_all_threads;	/* all server threads */

	struct llist_head	sp_idle_threads; /* idle server threads */

include/linux/sunrpc/svc_xprt.h

+1 −1
Original line number Diff line number Diff line
@@ -54,7 +54,7 @@ struct svc_xprt { 
	const struct svc_xprt_ops *xpt_ops;

	struct kref		xpt_ref;

	struct list_head	xpt_list;

	struct list_head	xpt_ready;

	struct lwq_node		xpt_ready;

	unsigned long		xpt_flags;



	struct svc_serv		*xpt_server;	/* service for transport */

net/sunrpc/svc.c

+1 −1
Original line number Diff line number Diff line
@@ -508,7 +508,7 @@ __svc_create(struct svc_program *prog, unsigned int bufsize, int npools, 
				i, serv->sv_name);



		pool->sp_id = i;

		INIT_LIST_HEAD(&pool->sp_sockets);

		lwq_init(&pool->sp_xprts);

		INIT_LIST_HEAD(&pool->sp_all_threads);

		init_llist_head(&pool->sp_idle_threads);

		spin_lock_init(&pool->sp_lock);

net/sunrpc/svc_xprt.c

+17 −40
Original line number Diff line number Diff line
@@ -201,7 +201,6 @@ void svc_xprt_init(struct net *net, struct svc_xprt_class *xcl, 
	kref_init(&xprt->xpt_ref);

	xprt->xpt_server = serv;

	INIT_LIST_HEAD(&xprt->xpt_list);

	INIT_LIST_HEAD(&xprt->xpt_ready);

	INIT_LIST_HEAD(&xprt->xpt_deferred);

	INIT_LIST_HEAD(&xprt->xpt_users);

	mutex_init(&xprt->xpt_mutex);
@@ -472,9 +471,7 @@ void svc_xprt_enqueue(struct svc_xprt *xprt) 
	pool = svc_pool_for_cpu(xprt->xpt_server);



	percpu_counter_inc(&pool->sp_sockets_queued);

	spin_lock_bh(&pool->sp_lock);

	list_add_tail(&xprt->xpt_ready, &pool->sp_sockets);

	spin_unlock_bh(&pool->sp_lock);

	lwq_enqueue(&xprt->xpt_ready, &pool->sp_xprts);



	svc_pool_wake_idle_thread(pool);

}
@@ -487,18 +484,9 @@ static struct svc_xprt *svc_xprt_dequeue(struct svc_pool *pool) 
{

	struct svc_xprt	*xprt = NULL;



	if (list_empty(&pool->sp_sockets))

		goto out;



	spin_lock_bh(&pool->sp_lock);

	if (likely(!list_empty(&pool->sp_sockets))) {

		xprt = list_first_entry(&pool->sp_sockets,

					struct svc_xprt, xpt_ready);

		list_del_init(&xprt->xpt_ready);

	xprt = lwq_dequeue(&pool->sp_xprts, struct svc_xprt, xpt_ready);

	if (xprt)

		svc_xprt_get(xprt);

	}

	spin_unlock_bh(&pool->sp_lock);

out:

	return xprt;

}
@@ -708,7 +696,7 @@ svc_thread_should_sleep(struct svc_rqst *rqstp) 
		return false;



	/* was a socket queued? */

	if (!list_empty(&pool->sp_sockets))

	if (!lwq_empty(&pool->sp_xprts))

		return false;



	/* are we shutting down? */
@@ -1050,7 +1038,6 @@ static void svc_delete_xprt(struct svc_xprt *xprt) 


	spin_lock_bh(&serv->sv_lock);

	list_del_init(&xprt->xpt_list);

	WARN_ON_ONCE(!list_empty(&xprt->xpt_ready));

	if (test_bit(XPT_TEMP, &xprt->xpt_flags))

		serv->sv_tmpcnt--;

	spin_unlock_bh(&serv->sv_lock);
@@ -1101,36 +1088,26 @@ static int svc_close_list(struct svc_serv *serv, struct list_head *xprt_list, st 
	return ret;

}



static struct svc_xprt *svc_dequeue_net(struct svc_serv *serv, struct net *net)

static void svc_clean_up_xprts(struct svc_serv *serv, struct net *net)

{

	struct svc_pool *pool;

	struct svc_xprt *xprt;

	struct svc_xprt *tmp;

	int i;



	for (i = 0; i < serv->sv_nrpools; i++) {

		pool = &serv->sv_pools[i];

		struct svc_pool *pool = &serv->sv_pools[i];

		struct llist_node *q, **t1, *t2;



		spin_lock_bh(&pool->sp_lock);

		list_for_each_entry_safe(xprt, tmp, &pool->sp_sockets, xpt_ready) {

			if (xprt->xpt_net != net)

				continue;

			list_del_init(&xprt->xpt_ready);

			spin_unlock_bh(&pool->sp_lock);

			return xprt;

		}

		spin_unlock_bh(&pool->sp_lock);

		q = lwq_dequeue_all(&pool->sp_xprts);

		lwq_for_each_safe(xprt, t1, t2, &q, xpt_ready) {

			if (xprt->xpt_net == net) {

				set_bit(XPT_CLOSE, &xprt->xpt_flags);

				svc_delete_xprt(xprt);

				xprt = NULL;

			}

	return NULL;

		}



static void svc_clean_up_xprts(struct svc_serv *serv, struct net *net)

{

	struct svc_xprt *xprt;



	while ((xprt = svc_dequeue_net(serv, net))) {

		set_bit(XPT_CLOSE, &xprt->xpt_flags);

		svc_delete_xprt(xprt);

		if (q)

			lwq_enqueue_batch(q, &pool->sp_xprts);

	}

}