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path: root/net/sunrpc/svc_xprt.c
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Diffstat (limited to 'net/sunrpc/svc_xprt.c')
-rw-r--r--net/sunrpc/svc_xprt.c127
1 files changed, 118 insertions, 9 deletions
diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index 2819ee093f3..c200d92e57e 100644
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -14,6 +14,8 @@
#define RPCDBG_FACILITY RPCDBG_SVCXPRT
+#define SVC_MAX_WAKING 5
+
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);
@@ -301,6 +303,7 @@ void svc_xprt_enqueue(struct svc_xprt *xprt)
struct svc_pool *pool;
struct svc_rqst *rqstp;
int cpu;
+ int thread_avail;
if (!(xprt->xpt_flags &
((1<<XPT_CONN)|(1<<XPT_DATA)|(1<<XPT_CLOSE)|(1<<XPT_DEFERRED))))
@@ -312,18 +315,14 @@ void svc_xprt_enqueue(struct svc_xprt *xprt)
spin_lock_bh(&pool->sp_lock);
- if (!list_empty(&pool->sp_threads) &&
- !list_empty(&pool->sp_sockets))
- printk(KERN_ERR
- "svc_xprt_enqueue: "
- "threads and transports both waiting??\n");
-
if (test_bit(XPT_DEAD, &xprt->xpt_flags)) {
/* Don't enqueue dead transports */
dprintk("svc: transport %p is dead, not enqueued\n", xprt);
goto out_unlock;
}
+ pool->sp_stats.packets++;
+
/* Mark transport as busy. It will remain in this state until
* the provider calls svc_xprt_received. We update XPT_BUSY
* atomically because it also guards against trying to enqueue
@@ -356,7 +355,15 @@ void svc_xprt_enqueue(struct svc_xprt *xprt)
}
process:
- if (!list_empty(&pool->sp_threads)) {
+ /* Work out whether threads are available */
+ thread_avail = !list_empty(&pool->sp_threads); /* threads are asleep */
+ if (pool->sp_nwaking >= SVC_MAX_WAKING) {
+ /* too many threads are runnable and trying to wake up */
+ thread_avail = 0;
+ pool->sp_stats.overloads_avoided++;
+ }
+
+ if (thread_avail) {
rqstp = list_entry(pool->sp_threads.next,
struct svc_rqst,
rq_list);
@@ -371,11 +378,15 @@ void svc_xprt_enqueue(struct svc_xprt *xprt)
svc_xprt_get(xprt);
rqstp->rq_reserved = serv->sv_max_mesg;
atomic_add(rqstp->rq_reserved, &xprt->xpt_reserved);
+ rqstp->rq_waking = 1;
+ pool->sp_nwaking++;
+ pool->sp_stats.threads_woken++;
BUG_ON(xprt->xpt_pool != pool);
wake_up(&rqstp->rq_wait);
} else {
dprintk("svc: transport %p put into queue\n", xprt);
list_add_tail(&xprt->xpt_ready, &pool->sp_sockets);
+ pool->sp_stats.sockets_queued++;
BUG_ON(xprt->xpt_pool != pool);
}
@@ -588,6 +599,7 @@ int svc_recv(struct svc_rqst *rqstp, long timeout)
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);
@@ -636,6 +648,11 @@ int svc_recv(struct svc_rqst *rqstp, long timeout)
return -EINTR;
spin_lock_bh(&pool->sp_lock);
+ if (rqstp->rq_waking) {
+ rqstp->rq_waking = 0;
+ pool->sp_nwaking--;
+ BUG_ON(pool->sp_nwaking < 0);
+ }
xprt = svc_xprt_dequeue(pool);
if (xprt) {
rqstp->rq_xprt = xprt;
@@ -668,12 +685,14 @@ int svc_recv(struct svc_rqst *rqstp, long timeout)
add_wait_queue(&rqstp->rq_wait, &wait);
spin_unlock_bh(&pool->sp_lock);
- schedule_timeout(timeout);
+ time_left = schedule_timeout(timeout);
try_to_freeze();
spin_lock_bh(&pool->sp_lock);
remove_wait_queue(&rqstp->rq_wait, &wait);
+ if (!time_left)
+ pool->sp_stats.threads_timedout++;
xprt = rqstp->rq_xprt;
if (!xprt) {
@@ -958,7 +977,7 @@ static struct cache_deferred_req *svc_defer(struct cache_req *req)
struct svc_rqst *rqstp = container_of(req, struct svc_rqst, rq_chandle);
struct svc_deferred_req *dr;
- if (rqstp->rq_arg.page_len)
+ if (rqstp->rq_arg.page_len || !rqstp->rq_usedeferral)
return NULL; /* if more than a page, give up FIXME */
if (rqstp->rq_deferred) {
dr = rqstp->rq_deferred;
@@ -1112,3 +1131,93 @@ int svc_xprt_names(struct svc_serv *serv, char *buf, int buflen)
return totlen;
}
EXPORT_SYMBOL_GPL(svc_xprt_names);
+
+
+/*----------------------------------------------------------------------------*/
+
+static void *svc_pool_stats_start(struct seq_file *m, loff_t *pos)
+{
+ unsigned int pidx = (unsigned int)*pos;
+ struct svc_serv *serv = m->private;
+
+ dprintk("svc_pool_stats_start, *pidx=%u\n", pidx);
+
+ lock_kernel();
+ /* bump up the pseudo refcount while traversing */
+ svc_get(serv);
+ unlock_kernel();
+
+ if (!pidx)
+ return SEQ_START_TOKEN;
+ return (pidx > serv->sv_nrpools ? NULL : &serv->sv_pools[pidx-1]);
+}
+
+static void *svc_pool_stats_next(struct seq_file *m, void *p, loff_t *pos)
+{
+ struct svc_pool *pool = p;
+ struct svc_serv *serv = m->private;
+
+ dprintk("svc_pool_stats_next, *pos=%llu\n", *pos);
+
+ if (p == SEQ_START_TOKEN) {
+ pool = &serv->sv_pools[0];
+ } else {
+ unsigned int pidx = (pool - &serv->sv_pools[0]);
+ if (pidx < serv->sv_nrpools-1)
+ pool = &serv->sv_pools[pidx+1];
+ else
+ pool = NULL;
+ }
+ ++*pos;
+ return pool;
+}
+
+static void svc_pool_stats_stop(struct seq_file *m, void *p)
+{
+ struct svc_serv *serv = m->private;
+
+ lock_kernel();
+ /* this function really, really should have been called svc_put() */
+ svc_destroy(serv);
+ unlock_kernel();
+}
+
+static int svc_pool_stats_show(struct seq_file *m, void *p)
+{
+ struct svc_pool *pool = p;
+
+ if (p == SEQ_START_TOKEN) {
+ seq_puts(m, "# pool packets-arrived sockets-enqueued threads-woken overloads-avoided threads-timedout\n");
+ return 0;
+ }
+
+ seq_printf(m, "%u %lu %lu %lu %lu %lu\n",
+ pool->sp_id,
+ pool->sp_stats.packets,
+ pool->sp_stats.sockets_queued,
+ pool->sp_stats.threads_woken,
+ pool->sp_stats.overloads_avoided,
+ pool->sp_stats.threads_timedout);
+
+ return 0;
+}
+
+static const struct seq_operations svc_pool_stats_seq_ops = {
+ .start = svc_pool_stats_start,
+ .next = svc_pool_stats_next,
+ .stop = svc_pool_stats_stop,
+ .show = svc_pool_stats_show,
+};
+
+int svc_pool_stats_open(struct svc_serv *serv, struct file *file)
+{
+ int err;
+
+ err = seq_open(file, &svc_pool_stats_seq_ops);
+ if (!err)
+ ((struct seq_file *) file->private_data)->private = serv;
+ return err;
+}
+EXPORT_SYMBOL(svc_pool_stats_open);
+
+/*----------------------------------------------------------------------------*/