[PATCH] PATCH 8/16: NFSD: RPC lists tidyup

Change sunrpc to use more list.h lists

The sunrpc client code uses home-grown doubly linked
lists to group
   - idle server threads
   - pending server sockets
   - waiting rpc tasks
   - all rpc tasks.

This patch converts all of these lists to <linux/list.h> lists and
also makes the list of all server sockets for a particular server into
a list.h list instead of a single-link list.

Possibly the least obvious change is replacing RPC_INIT_WAITQ
with RPC_WAITQ and INIT_RPC_WAITQ.  These follow the model of
LIST_HEAD and INIT_LIST_HEAD defined in list.h and are needed
to initialise the list_head in the rpc_waitq properly.

fs/nfs/flushd.c

@@ -50,7 +50,7 @@
 /*
  * This is the wait queue all cluster daemons sleep on
  */
-static struct rpc_wait_queue    flushd_queue = RPC_INIT_WAITQ("nfs_flushd");
+static RPC_WAITQ(flushd_queue, "nfs_flushd");
 
 /*
  * Local function declarations.

fs/nfs/unlink.c

@@ -24,7 +24,7 @@ struct nfs_unlinkdata {
 };
 
 static struct nfs_unlinkdata	*nfs_deletes;
-static struct rpc_wait_queue	nfs_delete_queue = RPC_INIT_WAITQ("nfs_delete_queue");
+static RPC_WAITQ(nfs_delete_queue, "nfs_delete_queue");
 
 /**
  * nfs_detach_unlinkdata - Remove asynchronous unlink from global list

include/linux/sunrpc/sched.h

@@ -34,13 +34,11 @@ struct rpc_message {
  * This is the RPC task struct
  */
 struct rpc_task {
-	struct rpc_task *	tk_prev;	/* wait queue links */
-	struct rpc_task *	tk_next;
+	struct list_head	tk_list;	/* wait queue links */
 #ifdef RPC_DEBUG
 	unsigned long		tk_magic;	/* 0xf00baa */
 #endif
-	struct rpc_task *	tk_next_task;	/* global list of tasks */
-	struct rpc_task *	tk_prev_task;	/* global list of tasks */
+	struct list_head	tk_task;	/* global list of tasks */
 	struct rpc_clnt *	tk_client;	/* RPC client */
 	struct rpc_rqst *	tk_rqstp;	/* RPC request */
 	int			tk_status;	/* result of last operation */
@@ -88,6 +86,20 @@ struct rpc_task {
 #define tk_auth			tk_client->cl_auth
 #define tk_xprt			tk_client->cl_xprt
 
+/* support walking a list of tasks on a wait queue */
+#define	task_for_each(task, pos, head) \
+	list_for_each(pos, head) \
+		if ((task=list_entry(pos, struct rpc_task, tk_list)),1)
+
+#define	task_for_first(task, head) \
+	if (!list_empty(head) &&  \
+	    ((task=list_entry((head)->next, struct rpc_task, tk_list)),1))
+
+/* .. and walking list of all tasks */
+#define	alltask_for_each(task, pos, head) \
+	list_for_each(pos, head) \
+		if ((task=list_entry(pos, struct rpc_task, tk_task)),1)
+
 typedef void			(*rpc_action)(struct rpc_task *);
 
 /*
@@ -133,16 +145,24 @@ typedef void			(*rpc_action)(struct rpc_task *);
  * RPC synchronization objects
  */
 struct rpc_wait_queue {
-	struct rpc_task *	task;
+	struct list_head	tasks;
 #ifdef RPC_DEBUG
 	char *			name;
 #endif
 };
 
 #ifndef RPC_DEBUG
-# define RPC_INIT_WAITQ(name)	((struct rpc_wait_queue) { NULL })
+# define RPC_WAITQ_INIT(var,qname) ((struct rpc_wait_queue) {LIST_HEAD_INIT(var)})
+# define RPC_WAITQ(var,qname)      struct rpc_wait_queue var = RPC_WAITQ_INIT(var.tasks,qname)
+# define INIT_RPC_WAITQ(ptr,qname) do { \
+	INIT_LIST_HEAD(&(ptr)->tasks); \
+	} while(0)
 #else
-# define RPC_INIT_WAITQ(name)	((struct rpc_wait_queue) { NULL, name })
+# define RPC_WAITQ_INIT(var,qname) ((struct rpc_wait_queue) {LIST_HEAD_INIT(var.tasks), qname})
+# define RPC_WAITQ(var,qname)      struct rpc_wait_queue var = RPC_WAITQ_INIT(var,qname)
+# define INIT_RPC_WAITQ(ptr,qname) do { \
+	INIT_LIST_HEAD(&(ptr)->tasks); (ptr)->name = qname; \
+	} while(0)
 #endif
 
 /*

include/linux/sunrpc/svc.h

@@ -27,8 +27,8 @@
  * We currently do not support more than one RPC program per daemon.
  */
 struct svc_serv {
-	struct svc_rqst *	sv_threads;	/* idle server threads */
-	struct svc_sock *	sv_sockets;	/* pending sockets */
+	struct list_head	sv_threads;	/* idle server threads */
+	struct list_head	sv_sockets;	/* pending sockets */
 	struct svc_program *	sv_program;	/* RPC program */
 	struct svc_stat *	sv_stats;	/* RPC statistics */
 	spinlock_t		sv_lock;
@@ -36,7 +36,7 @@ struct svc_serv {
 	unsigned int		sv_bufsz;	/* datagram buffer size */
 	unsigned int		sv_xdrsize;	/* XDR buffer size */
 
-	struct svc_sock *	sv_allsocks;	/* all sockets */
+	struct list_head	sv_allsocks;	/* all sockets */
 
 	char *			sv_name;	/* service name */
 };
@@ -89,8 +89,7 @@ struct svc_buf {
  * NOTE: First two items must be prev/next.
  */
 struct svc_rqst {
-	struct svc_rqst *	rq_prev;	/* idle list */
-	struct svc_rqst *	rq_next;
+	struct list_head	rq_list;	/* idle list */
 	struct svc_sock *	rq_sock;	/* socket */
 	struct sockaddr_in	rq_addr;	/* peer address */
 	int			rq_addrlen;

include/linux/sunrpc/svcsock.h

@@ -13,12 +13,10 @@
 
 /*
  * RPC server socket.
- * NOTE: First two items must be prev/next.
  */
 struct svc_sock {
-	struct svc_sock *	sk_prev;	/* list of ready sockets */
-	struct svc_sock *	sk_next;
-	struct svc_sock *	sk_list;	/* list of all sockets */
+	struct list_head	sk_ready;	/* list of ready sockets */
+	struct list_head	sk_list;	/* list of all sockets */
 	struct socket *		sk_sock;	/* berkeley socket layer */
 	struct sock *		sk_sk;		/* INET layer */
 	spinlock_t		sk_lock;

include/linux/sunrpc/types.h

@@ -12,60 +12,7 @@
 #include <linux/timer.h>
 #include <linux/tqueue.h>
 #include <linux/sunrpc/debug.h>
-
-/*
- * These are the RPC list manipulation primitives used everywhere.
- */
-struct rpc_listitem	{
-	struct rpc_listitem *	prev;
-	struct rpc_listitem *	next;
-};
-
-static __inline__ void
-__rpc_append_list(struct rpc_listitem **q, struct rpc_listitem *item)
-{
-	struct rpc_listitem	*next, *prev;
-
-	if (!(next = *q)) {
-		*q = item->next = item->prev = item;
-	} else {
-		prev = next->prev;
-		prev->next = item;
-		next->prev = item;
-		item->next = next;
-		item->prev = prev;
-	}
-}
-
-static __inline__ void
-__rpc_insert_list(struct rpc_listitem **q, struct rpc_listitem *item)
-{
-	__rpc_append_list(q, item);
-	*q = item;
-}
-
-static __inline__ void
-__rpc_remove_list(struct rpc_listitem **q, struct rpc_listitem *item)
-{
-	struct rpc_listitem	*prev = item->prev,
-				*next = item->next;
-
-	if (item != prev) {
-		next->prev = prev;
-		prev->next = next;
-	} else {
-		next = NULL;
-	}
-	if (*q == item)
-		*q = next;
-}
-
-#define rpc_insert_list(q, i) \
-      __rpc_insert_list((struct rpc_listitem **) q, (struct rpc_listitem *) i)
-#define rpc_append_list(q, i) \
-      __rpc_append_list((struct rpc_listitem **) q, (struct rpc_listitem *) i)
-#define rpc_remove_list(q, i) \
-      __rpc_remove_list((struct rpc_listitem **) q, (struct rpc_listitem *) i)
+#include <linux/list.h>
 
 /*
  * Shorthands

net/sunrpc/clnt.c

@@ -103,7 +103,7 @@ rpc_create_client(struct rpc_xprt *xprt, char *servname,
 	clnt->cl_vers     = version->number;
 	clnt->cl_prot     = xprt->prot;
 	clnt->cl_stats    = program->stats;
-	clnt->cl_bindwait = RPC_INIT_WAITQ("bindwait");
+	INIT_RPC_WAITQ(&clnt->cl_bindwait, "bindwait");
 
 	if (!clnt->cl_port)
 		clnt->cl_autobind = 1;

net/sunrpc/sched.c

@@ -41,23 +41,23 @@ static void			rpciod_killall(void);
  * handler, or while executing another RPC task, it is put on
  * schedq, and rpciod is woken up.
  */
-static struct rpc_wait_queue	schedq = RPC_INIT_WAITQ("schedq");
+static RPC_WAITQ(schedq, "schedq");
 
 /*
  * RPC tasks that create another task (e.g. for contacting the portmapper)
  * will wait on this queue for their child's completion
  */
-static struct rpc_wait_queue	childq = RPC_INIT_WAITQ("childq");
+static RPC_WAITQ(childq, "childq");
 
 /*
  * RPC tasks sit here while waiting for conditions to improve.
  */
-static struct rpc_wait_queue	delay_queue = RPC_INIT_WAITQ("delayq");
+static RPC_WAITQ(delay_queue, "delayq");
 
 /*
  * All RPC tasks are linked into this list
  */
-static struct rpc_task *	all_tasks;
+static LIST_HEAD(all_tasks);
 
 /*
  * rpciod-related stuff
@@ -194,9 +194,9 @@ __rpc_add_wait_queue(struct rpc_wait_queue *queue, struct rpc_task *task)
 		return -EWOULDBLOCK;
 	}
 	if (RPC_IS_SWAPPER(task))
-		rpc_insert_list(&queue->task, task);
+		list_add(&task->tk_list, &queue->tasks);
 	else
-		rpc_append_list(&queue->task, task);
+		list_add_tail(&task->tk_list, &queue->tasks);
 	task->tk_rpcwait = queue;
 
 	dprintk("RPC: %4d added to queue %p \"%s\"\n",
@@ -228,7 +228,7 @@ __rpc_remove_wait_queue(struct rpc_task *task)
 	if (!queue)
 		return;
 
-	rpc_remove_list(&queue->task, task);
+	list_del(&task->tk_list);
 	task->tk_rpcwait = NULL;
 
 	dprintk("RPC: %4d removed from queue %p \"%s\"\n",
@@ -450,11 +450,11 @@ rpc_wake_up_task(struct rpc_task *task)
 struct rpc_task *
 rpc_wake_up_next(struct rpc_wait_queue *queue)
 {
-	struct rpc_task	*task;
+	struct rpc_task	*task = NULL;
 
 	dprintk("RPC:      wake_up_next(%p \"%s\")\n", queue, rpc_qname(queue));
 	spin_lock_bh(&rpc_queue_lock);
-	if ((task = queue->task) != 0)
+	task_for_first(task, &queue->tasks)
 		__rpc_wake_up_task(task);
 	spin_unlock_bh(&rpc_queue_lock);
 
@@ -470,9 +470,12 @@ rpc_wake_up_next(struct rpc_wait_queue *queue)
 void
 rpc_wake_up(struct rpc_wait_queue *queue)
 {
+	struct rpc_task *task;
+
 	spin_lock_bh(&rpc_queue_lock);
-	while (queue->task)
-		__rpc_wake_up_task(queue->task);
+	while (!list_empty(&queue->tasks))
+		task_for_first(task, &queue->tasks)
+			__rpc_wake_up_task(task);
 	spin_unlock_bh(&rpc_queue_lock);
 }
 
@@ -489,10 +492,12 @@ rpc_wake_up_status(struct rpc_wait_queue *queue, int status)
 	struct rpc_task *task;
 
 	spin_lock_bh(&rpc_queue_lock);
-	while ((task = queue->task) != NULL) {
+	while (!list_empty(&queue->tasks)) {
+		task_for_first(task, &queue->tasks) {
 			task->tk_status = status;
 			__rpc_wake_up_task(task);
 		}
+	}
 	spin_unlock_bh(&rpc_queue_lock);
 }
 
@@ -703,10 +708,8 @@ __rpc_schedule(void)
 		rpciod_tcp_dispatcher();
 
 		spin_lock_bh(&rpc_queue_lock);
-		if (!(task = schedq.task)) {
-			spin_unlock_bh(&rpc_queue_lock);
-			break;
-		}
+
+		task_for_first(task, &schedq.tasks) {
 			if (task->tk_lock) {
 				spin_unlock_bh(&rpc_queue_lock);
 				printk(KERN_ERR "RPC: Locked task was scheduled !!!!\n");
@@ -720,6 +723,10 @@ __rpc_schedule(void)
 			spin_unlock_bh(&rpc_queue_lock);
 
 			__rpc_execute(task);
+		} else {
+			spin_unlock_bh(&rpc_queue_lock);
+			break;
+		}
 
 		if (++count >= 200 || need_resched()) {
 			count = 0;
@@ -814,11 +821,7 @@ rpc_init_task(struct rpc_task *task, struct rpc_clnt *clnt,
 
 	/* Add to global list of all tasks */
 	spin_lock(&rpc_sched_lock);
-	task->tk_next_task = all_tasks;
-	task->tk_prev_task = NULL;
-	if (all_tasks)
-		all_tasks->tk_prev_task = task;
-	all_tasks = task;
+	list_add(&task->tk_task, &all_tasks);
 	spin_unlock(&rpc_sched_lock);
 
 	if (clnt)
@@ -877,8 +880,6 @@ rpc_new_task(struct rpc_clnt *clnt, rpc_action callback, int flags)
 void
 rpc_release_task(struct rpc_task *task)
 {
-	struct rpc_task	*next, *prev;
-
 	dprintk("RPC: %4d release task\n", task->tk_pid);
 
 #ifdef RPC_DEBUG
@@ -892,15 +893,7 @@ rpc_release_task(struct rpc_task *task)
 
 	/* Remove from global task list */
 	spin_lock(&rpc_sched_lock);
-	prev = task->tk_prev_task;
-	next = task->tk_next_task;
-	if (next)
-		next->tk_prev_task = prev;
-	if (prev)
-		prev->tk_next_task = next;
-	else
-		all_tasks = next;
-	task->tk_next_task = task->tk_prev_task = NULL;
+	list_del(&task->tk_task);
 	spin_unlock(&rpc_sched_lock);
 
 	/* Protect the execution below. */
@@ -954,14 +947,13 @@ static inline struct rpc_task *
 rpc_find_parent(struct rpc_task *child)
 {
 	struct rpc_task	*task, *parent;
+	struct list_head *le;
 
 	parent = (struct rpc_task *) child->tk_calldata;
-	if ((task = childq.task) != NULL) {
-		do {
+	task_for_each(task, le, &childq.tasks)
 		if (task == parent)
 			return parent;
-		} while ((task = task->tk_next) != childq.task);
-	}
+
 	return NULL;
 }
 
@@ -1015,7 +1007,8 @@ rpc_run_child(struct rpc_task *task, struct rpc_task *child, rpc_action func)
 void
 rpc_killall_tasks(struct rpc_clnt *clnt)
 {
-	struct rpc_task	**q, *rovr;
+	struct rpc_task	*rovr;
+	struct list_head *le;
 
 	dprintk("RPC:      killing all tasks for client %p\n", clnt);
 
@@ -1023,13 +1016,12 @@ rpc_killall_tasks(struct rpc_clnt *clnt)
 	 * Spin lock all_tasks to prevent changes...
 	 */
 	spin_lock(&rpc_sched_lock);
-	for (q = &all_tasks; (rovr = *q); q = &rovr->tk_next_task) {
+	alltask_for_each(rovr, le, &all_tasks)
 		if (!clnt || rovr->tk_client == clnt) {
 			rovr->tk_flags |= RPC_TASK_KILLED;
 			rpc_exit(rovr, -EIO);
 			rpc_wake_up_task(rovr);
 		}
-	}
 	spin_unlock(&rpc_sched_lock);
 }
 
@@ -1038,7 +1030,7 @@ static DECLARE_MUTEX_LOCKED(rpciod_running);
 static inline int
 rpciod_task_pending(void)
 {
-	return schedq.task != NULL || xprt_tcp_pending();
+	return !list_empty(&schedq.tasks) || xprt_tcp_pending();
 }
 
 
@@ -1090,7 +1082,7 @@ rpciod(void *ptr)
 	}
 
 	dprintk("RPC: rpciod shutdown commences\n");
-	if (all_tasks) {
+	if (!list_empty(&all_tasks)) {
 		printk(KERN_ERR "rpciod: active tasks at shutdown?!\n");
 		rpciod_killall();
 	}
@@ -1108,11 +1100,11 @@ rpciod_killall(void)
 {
 	unsigned long flags;
 
-	while (all_tasks) {
+	while (!list_empty(&all_tasks)) {
 		clear_thread_flag(TIF_SIGPENDING);
 		rpc_killall_tasks(NULL);
 		__rpc_schedule();
-		if (all_tasks) {
+		if (!list_empty(&all_tasks)) {
 			dprintk("rpciod_killall: waiting for tasks to exit\n");
 			yield();
 		}
@@ -1207,25 +1199,23 @@ rpciod_down(void)
 #ifdef RPC_DEBUG
 void rpc_show_tasks(void)
 {
-	struct rpc_task *t = all_tasks, *next;
+	struct list_head *le;
+	struct rpc_task *t;
 
 	spin_lock(&rpc_sched_lock);
-	t = all_tasks;
-	if (!t) {
+	if (list_empty(&all_tasks)) {
 		spin_unlock(&rpc_sched_lock);
 		return;
 	}
 	printk("-pid- proc flgs status -client- -prog- --rqstp- -timeout "
 		"-rpcwait -action- --exit--\n");
-	for (; t; t = next) {
-		next = t->tk_next_task;
+	alltask_for_each(t, le, &all_tasks)
 		printk("%05d %04d %04x %06d %8p %6d %8p %08ld %8s %8p %8p\n",
 			t->tk_pid, t->tk_msg.rpc_proc, t->tk_flags, t->tk_status,
 			t->tk_client, t->tk_client->cl_prog,
 			t->tk_rqstp, t->tk_timeout,
 			t->tk_rpcwait ? rpc_qname(t->tk_rpcwait) : " <NULL> ",
 			t->tk_action, t->tk_exit);
-	}
 	spin_unlock(&rpc_sched_lock);
 }
 #endif

net/sunrpc/svc.c

@@ -44,6 +44,9 @@ svc_create(struct svc_program *prog, unsigned int bufsize, unsigned int xdrsize)
 	serv->sv_stats     = prog->pg_stats;
 	serv->sv_bufsz	   = bufsize? bufsize : 4096;
 	serv->sv_xdrsize   = xdrsize;
+	INIT_LIST_HEAD(&serv->sv_threads);
+	INIT_LIST_HEAD(&serv->sv_sockets);
+	INIT_LIST_HEAD(&serv->sv_allsocks);
 	spin_lock_init(&serv->sv_lock);
 
 	serv->sv_name      = prog->pg_name;
@@ -72,8 +75,12 @@ svc_destroy(struct svc_serv *serv)
 	} else
 		printk("svc_destroy: no threads for serv=%p!\n", serv);
 
-	while ((svsk = serv->sv_allsocks) != NULL)
+	while (!list_empty(&serv->sv_allsocks)) {
+		svsk = list_entry(serv->sv_allsocks.next,
+				  struct svc_sock,
+				  sk_list);
 		svc_delete_socket(svsk);
+	}
 
 	/* Unregister service with the portmapper */
 	svc_register(serv, 0, 0);

net/sunrpc/svcsock.c

@@ -63,11 +63,14 @@ static int		svc_udp_sendto(struct svc_rqst *);
 
 /*
  * Queue up an idle server thread.  Must have serv->sv_lock held.
+ * Note: this is really a stack rather than a queue, so that we only
+ * use as many different threads as we need, and the rest don't polute
+ * the cache.
  */
 static inline void
 svc_serv_enqueue(struct svc_serv *serv, struct svc_rqst *rqstp)
 {
-	rpc_append_list(&serv->sv_threads, rqstp);
+	list_add(&rqstp->rq_list, &serv->sv_threads);
 }
 
 /*
@@ -76,7 +79,7 @@ svc_serv_enqueue(struct svc_serv *serv, struct svc_rqst *rqstp)
 static inline void
 svc_serv_dequeue(struct svc_serv *serv, struct svc_rqst *rqstp)
 {
-	rpc_remove_list(&serv->sv_threads, rqstp);
+	list_del(&rqstp->rq_list);
 }
 
 /*
@@ -110,7 +113,8 @@ svc_sock_enqueue(struct svc_sock *svsk)
 	/* NOTE: Local BH is already disabled by our caller. */
 	spin_lock(&serv->sv_lock);
 
-	if (serv->sv_threads && serv->sv_sockets)
+	if (!list_empty(&serv->sv_threads) && 
+	    !list_empty(&serv->sv_sockets))
 		printk(KERN_ERR
 			"svc_sock_enqueue: threads and sockets both waiting??\n");
 
@@ -126,7 +130,10 @@ svc_sock_enqueue(struct svc_sock *svsk)
 	 */
 	svsk->sk_busy = 1;
 
-	if ((rqstp = serv->sv_threads) != NULL) {
+	if (!list_empty(&serv->sv_threads)) {
+		rqstp = list_entry(serv->sv_threads.next,
+				   struct svc_rqst,
+				   rq_list);
 		dprintk("svc: socket %p served by daemon %p\n",
 			svsk->sk_sk, rqstp);
 		svc_serv_dequeue(serv, rqstp);
@@ -139,7 +146,7 @@ svc_sock_enqueue(struct svc_sock *svsk)
 		wake_up(&rqstp->rq_wait);
 	} else {
 		dprintk("svc: socket %p put into queue\n", svsk->sk_sk);
-		rpc_append_list(&serv->sv_sockets, svsk);
+		list_add_tail(&svsk->sk_ready, &serv->sv_sockets);
 		svsk->sk_qued = 1;
 	}
 
@@ -155,14 +162,16 @@ svc_sock_dequeue(struct svc_serv *serv)
 {
 	struct svc_sock	*svsk;
 
-	if ((svsk = serv->sv_sockets) != NULL)
-		rpc_remove_list(&serv->sv_sockets, svsk);
+	if (list_empty(&serv->sv_sockets))
+		return NULL;
+
+	svsk = list_entry(serv->sv_sockets.next,
+			  struct svc_sock, sk_ready);
+	list_del(&svsk->sk_ready);
 
-	if (svsk) {
 	dprintk("svc: socket %p dequeued, inuse=%d\n",
 		svsk->sk_sk, svsk->sk_inuse);
 	svsk->sk_qued = 0;
-	}
 
 	return svsk;
 }
@@ -238,7 +247,10 @@ svc_wake_up(struct svc_serv *serv)
 	struct svc_rqst	*rqstp;
 
 	spin_lock_bh(&serv->sv_lock);
-	if ((rqstp = serv->sv_threads) != NULL) {
+	if (!list_empty(&serv->sv_threads)) {
+		rqstp = list_entry(serv->sv_threads.next,
+				   struct svc_rqst,
+				   rq_list);
 		dprintk("svc: daemon %p woken up.\n", rqstp);
 		/*
 		svc_serv_dequeue(serv, rqstp);
@@ -958,8 +970,7 @@ if (svsk->sk_sk == NULL)
 	}
 
 	spin_lock_bh(&serv->sv_lock);
-	svsk->sk_list = serv->sv_allsocks;
-	serv->sv_allsocks = svsk;
+	list_add(&svsk->sk_list, &serv->sv_allsocks);
 	spin_unlock_bh(&serv->sv_lock);
 
 	dprintk("svc: svc_setup_socket created %p (inet %p)\n",
@@ -1020,7 +1031,6 @@ svc_create_socket(struct svc_serv *serv, int protocol, struct sockaddr_in *sin)
 void
 svc_delete_socket(struct svc_sock *svsk)
 {
-	struct svc_sock	**rsk;
 	struct svc_serv	*serv;
 	struct sock	*sk;
 
@@ -1034,17 +1044,9 @@ svc_delete_socket(struct svc_sock *svsk)
 
 	spin_lock_bh(&serv->sv_lock);
 
-	for (rsk = &serv->sv_allsocks; *rsk; rsk = &(*rsk)->sk_list) {
-		if (*rsk == svsk)
-			break;
-	}
-	if (!*rsk) {
-		spin_unlock_bh(&serv->sv_lock);
-		return;
-	}
-	*rsk = svsk->sk_list;
+	list_del(&svsk->sk_list);
 	if (svsk->sk_qued)
-		rpc_remove_list(&serv->sv_sockets, svsk);
+		list_del(&svsk->sk_ready);
 
 
 	svsk->sk_dead = 1;

net/sunrpc/xprt.c

@@ -542,25 +542,15 @@ xprt_reconn_status(struct rpc_task *task)
 static inline struct rpc_rqst *
 xprt_lookup_rqst(struct rpc_xprt *xprt, u32 xid)
 {
-	struct rpc_task	*head, *task;
 	struct rpc_rqst	*req;
-	int		safe = 0;
+	struct list_head *le;
+	struct rpc_task *task;
 
 	spin_lock_bh(&rpc_queue_lock);
-	if ((head = xprt->pending.task) != NULL) {
-		task = head;
-		do {
+	task_for_each(task, le, &xprt->pending.tasks)
 		if ((req = task->tk_rqstp) && req->rq_xid == xid)
 			goto out;
-			task = task->tk_next;
-			if (++safe > 100) {
-				printk("xprt_lookup_rqst: loop in Q!\n");
-				goto out_bad;
-			}
-		} while (task != head);
-	}
 	dprintk("RPC:      unknown XID %08x in reply.\n", xid);
- out_bad:
 	req = NULL;
  out:
 	if (req && !__rpc_lock_task(req->rq_task))
@@ -1487,9 +1477,9 @@ xprt_setup(struct socket *sock, int proto,
 	} else
 		xprt_default_timeout(&xprt->timeout, xprt->prot);
 
-	xprt->pending = RPC_INIT_WAITQ("xprt_pending");
-	xprt->sending = RPC_INIT_WAITQ("xprt_sending");
-	xprt->backlog = RPC_INIT_WAITQ("xprt_backlog");
+	INIT_RPC_WAITQ(&xprt->pending, "xprt_pending");
+	INIT_RPC_WAITQ(&xprt->sending, "xprt_sending");
+	INIT_RPC_WAITQ(&xprt->backlog, "xprt_backlog");
 
 	/* initialize free list */
 	for (i = 0, req = xprt->slot; i < RPC_MAXREQS-1; i++, req++)