Commit 15d39883 authored by NeilBrown's avatar NeilBrown Committed by Chuck Lever
Browse files

SUNRPC: change the back-channel queue to lwq 



This removes the need to store and update back-links in the list.
It also remove the need for the _bh version of spin_lock().

Signed-off-by: default avatarNeilBrown <neilb@suse.de>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
parent 580a2575

include/linux/sunrpc/svc.h

+1 −2
Original line number Diff line number Diff line
@@ -90,10 +90,9 @@ struct svc_serv { 
	int			(*sv_threadfn)(void *data);



#if defined(CONFIG_SUNRPC_BACKCHANNEL)

	struct list_head	sv_cb_list;	/* queue for callback requests

	struct lwq		sv_cb_list;	/* queue for callback requests

						 * that arrive over the same

						 * connection */

	spinlock_t		sv_cb_lock;	/* protects the svc_cb_list */

	bool			sv_bc_enabled;	/* service uses backchannel */

#endif /* CONFIG_SUNRPC_BACKCHANNEL */

};

include/linux/sunrpc/xprt.h

+2 −1
Original line number Diff line number Diff line
@@ -57,6 +57,7 @@ struct xprt_class; 
struct seq_file;

struct svc_serv;

struct net;

#include <linux/lwq.h>



/*

 * This describes a complete RPC request
@@ -121,7 +122,7 @@ struct rpc_rqst { 
	int			rq_ntrans;



#if defined(CONFIG_SUNRPC_BACKCHANNEL)

	struct list_head	rq_bc_list;	/* Callback service list */

	struct lwq_node		rq_bc_list;	/* Callback service list */

	unsigned long		rq_bc_pa_state;	/* Backchannel prealloc state */

	struct list_head	rq_bc_pa_list;	/* Backchannel prealloc list */

#endif /* CONFIG_SUNRPC_BACKCHANEL */

net/sunrpc/backchannel_rqst.c

+1 −4
Original line number Diff line number Diff line
@@ -83,7 +83,6 @@ static struct rpc_rqst *xprt_alloc_bc_req(struct rpc_xprt *xprt) 
		return NULL;



	req->rq_xprt = xprt;

	INIT_LIST_HEAD(&req->rq_bc_list);



	/* Preallocate one XDR receive buffer */

	if (xprt_alloc_xdr_buf(&req->rq_rcv_buf, gfp_flags) < 0) {
@@ -367,8 +366,6 @@ void xprt_complete_bc_request(struct rpc_rqst *req, uint32_t copied) 


	dprintk("RPC:       add callback request to list\n");

	xprt_get(xprt);

	spin_lock(&bc_serv->sv_cb_lock);

	list_add(&req->rq_bc_list, &bc_serv->sv_cb_list);

	spin_unlock(&bc_serv->sv_cb_lock);

	lwq_enqueue(&req->rq_bc_list, &bc_serv->sv_cb_list);

	svc_pool_wake_idle_thread(&bc_serv->sv_pools[0]);

}

net/sunrpc/svc.c

+1 −2
Original line number Diff line number Diff line
@@ -438,8 +438,7 @@ EXPORT_SYMBOL_GPL(svc_bind); 
static void

__svc_init_bc(struct svc_serv *serv)

{

	INIT_LIST_HEAD(&serv->sv_cb_list);

	spin_lock_init(&serv->sv_cb_lock);

	lwq_init(&serv->sv_cb_list);

}

#else

static void

net/sunrpc/svc_xprt.c

+3 −9
Original line number Diff line number Diff line
@@ -705,7 +705,7 @@ svc_thread_should_sleep(struct svc_rqst *rqstp) 


#if defined(CONFIG_SUNRPC_BACKCHANNEL)

	if (svc_is_backchannel(rqstp)) {

		if (!list_empty(&rqstp->rq_server->sv_cb_list))

		if (!lwq_empty(&rqstp->rq_server->sv_cb_list))

			return false;

	}

#endif
@@ -878,18 +878,12 @@ void svc_recv(struct svc_rqst *rqstp) 
		struct svc_serv *serv = rqstp->rq_server;

		struct rpc_rqst *req;



		spin_lock_bh(&serv->sv_cb_lock);

		req = list_first_entry_or_null(&serv->sv_cb_list,

		req = lwq_dequeue(&serv->sv_cb_list,

				  struct rpc_rqst, rq_bc_list);

		if (req) {

			list_del(&req->rq_bc_list);

			spin_unlock_bh(&serv->sv_cb_lock);

			svc_thread_wake_next(rqstp);



			svc_process_bc(req, rqstp);

			return;

		}

		spin_unlock_bh(&serv->sv_cb_lock);

	}

#endif

}