svc: Make deferral processing xprt independent

This patch moves the transport independent sk_deferred list to the svc_xprt
structure and updates the svc_deferred_req structure to keep pointers to
svc_xprt's directly. The deferral processing code is also moved out of the
transport dependent recvfrom functions and into the generic svc_recv path.

Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Acked-by: Neil Brown <neilb@suse.de>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Greg Banks <gnb@sgi.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h
index cfb2652..40adc9d 100644 (file)
--- a/include/linux/sunrpc/svc.h
+++ b/include/linux/sunrpc/svc.h
@@ -320,7 +320,7 @@ static inline void svc_free_res_pages(struct svc_rqst *rqstp)
 
 struct svc_deferred_req {
        u32                     prot;   /* protocol (UDP or TCP) */
-       struct svc_sock         *svsk;
+       struct svc_xprt         *xprt;
        struct sockaddr_storage addr;   /* where reply must go */
        size_t                  addrlen;
        union svc_addr_u        daddr;  /* where reply must come from */

diff --git a/include/linux/sunrpc/svc_xprt.h b/include/linux/sunrpc/svc_xprt.h
index 1b5da39..6a8445b 100644 (file)
--- a/include/linux/sunrpc/svc_xprt.h
+++ b/include/linux/sunrpc/svc_xprt.h
@@ -59,6 +59,8 @@ struct svc_xprt {
        spinlock_t              xpt_lock;       /* protects sk_deferred
                                                 * and xpt_auth_cache */
        void                    *xpt_auth_cache;/* auth cache */
+       struct list_head        xpt_deferred;   /* deferred requests that need
+                                                * to be revisted */
 };
 
 int    svc_reg_xprt_class(struct svc_xprt_class *);

diff --git a/include/linux/sunrpc/svcsock.h b/include/linux/sunrpc/svcsock.h
index f2ed6a2..96a229e 100644 (file)
--- a/include/linux/sunrpc/svcsock.h
+++ b/include/linux/sunrpc/svcsock.h
@@ -20,9 +20,6 @@ struct svc_sock {
        struct socket *         sk_sock;        /* berkeley socket layer */
        struct sock *           sk_sk;          /* INET layer */
 
-       struct list_head        sk_deferred;    /* deferred requests that need to
-                                                * be revisted */
-
        /* We keep the old state_change and data_ready CB's here */
        void                    (*sk_ostate)(struct sock *);
        void                    (*sk_odata)(struct sock *, int bytes);

diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index d2ac130..023aeb0 100644 (file)
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -102,6 +102,7 @@ void svc_xprt_init(struct svc_xprt_class *xcl, struct svc_xprt *xprt,
        xprt->xpt_server = serv;
        INIT_LIST_HEAD(&xprt->xpt_list);
        INIT_LIST_HEAD(&xprt->xpt_ready);
+       INIT_LIST_HEAD(&xprt->xpt_deferred);
        mutex_init(&xprt->xpt_mutex);
        spin_lock_init(&xprt->xpt_lock);
 }

diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index 5c9422c..9d0a9e6 100644 (file)
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -89,7 +89,7 @@ static void           svc_close_xprt(struct svc_xprt *xprt);
 static void            svc_sock_detach(struct svc_xprt *);
 static void            svc_sock_free(struct svc_xprt *);
 
-static struct svc_deferred_req *svc_deferred_dequeue(struct svc_sock *svsk);
+static struct svc_deferred_req *svc_deferred_dequeue(struct svc_xprt *xprt);
 static int svc_deferred_recv(struct svc_rqst *rqstp);
 static struct cache_deferred_req *svc_defer(struct cache_req *req);
 static struct svc_xprt *svc_create_socket(struct svc_serv *, int,
@@ -771,11 +771,6 @@ svc_udp_recvfrom(struct svc_rqst *rqstp)
                                (serv->sv_nrthreads+3) * serv->sv_max_mesg,
                                (serv->sv_nrthreads+3) * serv->sv_max_mesg);
 
-       if ((rqstp->rq_deferred = svc_deferred_dequeue(svsk))) {
-               svc_xprt_received(&svsk->sk_xprt);
-               return svc_deferred_recv(rqstp);
-       }
-
        clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
        skb = NULL;
        err = kernel_recvmsg(svsk->sk_sock, &msg, NULL,
@@ -1138,11 +1133,6 @@ svc_tcp_recvfrom(struct svc_rqst *rqstp)
                test_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags),
                test_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags));
 
-       if ((rqstp->rq_deferred = svc_deferred_dequeue(svsk))) {
-               svc_xprt_received(&svsk->sk_xprt);
-               return svc_deferred_recv(rqstp);
-       }
-
        if (test_and_clear_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags))
                /* sndbuf needs to have room for one request
                 * per thread, otherwise we can stall even when the
@@ -1601,7 +1591,12 @@ svc_recv(struct svc_rqst *rqstp, long timeout)
                dprintk("svc: server %p, pool %u, socket %p, inuse=%d\n",
                        rqstp, pool->sp_id, svsk,
                        atomic_read(&svsk->sk_xprt.xpt_ref.refcount));
-               len = svsk->sk_xprt.xpt_ops->xpo_recvfrom(rqstp);
+               rqstp->rq_deferred = svc_deferred_dequeue(&svsk->sk_xprt);
+               if (rqstp->rq_deferred) {
+                       svc_xprt_received(&svsk->sk_xprt);
+                       len = svc_deferred_recv(rqstp);
+               } else
+                       len = svsk->sk_xprt.xpt_ops->xpo_recvfrom(rqstp);
                dprintk("svc: got len=%d\n", len);
        }
 
@@ -1758,7 +1753,6 @@ static struct svc_sock *svc_setup_socket(struct svc_serv *serv,
        svsk->sk_ostate = inet->sk_state_change;
        svsk->sk_odata = inet->sk_data_ready;
        svsk->sk_owspace = inet->sk_write_space;
-       INIT_LIST_HEAD(&svsk->sk_deferred);
 
        /* Initialize the socket */
        if (sock->type == SOCK_DGRAM)
@@ -1976,22 +1970,21 @@ void svc_close_all(struct list_head *xprt_list)
 static void svc_revisit(struct cache_deferred_req *dreq, int too_many)
 {
        struct svc_deferred_req *dr = container_of(dreq, struct svc_deferred_req, handle);
-       struct svc_sock *svsk;
+       struct svc_xprt *xprt = dr->xprt;
 
        if (too_many) {
-               svc_xprt_put(&dr->svsk->sk_xprt);
+               svc_xprt_put(xprt);
                kfree(dr);
                return;
        }
        dprintk("revisit queued\n");
-       svsk = dr->svsk;
-       dr->svsk = NULL;
-       spin_lock(&svsk->sk_xprt.xpt_lock);
-       list_add(&dr->handle.recent, &svsk->sk_deferred);
-       spin_unlock(&svsk->sk_xprt.xpt_lock);
-       set_bit(XPT_DEFERRED, &svsk->sk_xprt.xpt_flags);
-       svc_xprt_enqueue(&svsk->sk_xprt);
-       svc_xprt_put(&svsk->sk_xprt);
+       dr->xprt = NULL;
+       spin_lock(&xprt->xpt_lock);
+       list_add(&dr->handle.recent, &xprt->xpt_deferred);
+       spin_unlock(&xprt->xpt_lock);
+       set_bit(XPT_DEFERRED, &xprt->xpt_flags);
+       svc_xprt_enqueue(xprt);
+       svc_xprt_put(xprt);
 }
 
 static struct cache_deferred_req *
@@ -2022,7 +2015,7 @@ svc_defer(struct cache_req *req)
                memcpy(dr->args, rqstp->rq_arg.head[0].iov_base-skip, dr->argslen<<2);
        }
        svc_xprt_get(rqstp->rq_xprt);
-       dr->svsk = rqstp->rq_sock;
+       dr->xprt = rqstp->rq_xprt;
 
        dr->handle.revisit = svc_revisit;
        return &dr->handle;
@@ -2048,21 +2041,21 @@ static int svc_deferred_recv(struct svc_rqst *rqstp)
 }
 
 
-static struct svc_deferred_req *svc_deferred_dequeue(struct svc_sock *svsk)
+static struct svc_deferred_req *svc_deferred_dequeue(struct svc_xprt *xprt)
 {
        struct svc_deferred_req *dr = NULL;
 
-       if (!test_bit(XPT_DEFERRED, &svsk->sk_xprt.xpt_flags))
+       if (!test_bit(XPT_DEFERRED, &xprt->xpt_flags))
                return NULL;
-       spin_lock(&svsk->sk_xprt.xpt_lock);
-       clear_bit(XPT_DEFERRED, &svsk->sk_xprt.xpt_flags);
-       if (!list_empty(&svsk->sk_deferred)) {
-               dr = list_entry(svsk->sk_deferred.next,
+       spin_lock(&xprt->xpt_lock);
+       clear_bit(XPT_DEFERRED, &xprt->xpt_flags);
+       if (!list_empty(&xprt->xpt_deferred)) {
+               dr = list_entry(xprt->xpt_deferred.next,
                                struct svc_deferred_req,
                                handle.recent);
                list_del_init(&dr->handle.recent);
-               set_bit(XPT_DEFERRED, &svsk->sk_xprt.xpt_flags);
+               set_bit(XPT_DEFERRED, &xprt->xpt_flags);
        }
-       spin_unlock(&svsk->sk_xprt.xpt_lock);
+       spin_unlock(&xprt->xpt_lock);
        return dr;
 }