Revert "knfsd: avoid overloading the CPU scheduler with enormous load averages"
This reverts commit 59a252ff8c0f2fa32c896f69d56ae33e641ce7ad.
This helps in an entirely cached workload but not necessarily in
workloads that require waiting on disk.
Conflicts:
include/linux/sunrpc/svc.h
net/sunrpc/svc_xprt.c
Reported-by: Simon Kirby <sim@hostway.ca>
Tested-by: Jesper Krogh <jesper@krogh.cc>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index df124f7..2c58b75 100644
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -16,8 +16,6 @@
#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);
@@ -306,7 +304,6 @@
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))))
@@ -318,6 +315,12 @@
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);
@@ -358,15 +361,7 @@
}
process:
- /* 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) {
+ if (!list_empty(&pool->sp_threads)) {
rqstp = list_entry(pool->sp_threads.next,
struct svc_rqst,
rq_list);
@@ -381,8 +376,6 @@
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);
@@ -651,11 +644,6 @@
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;
@@ -1204,16 +1192,15 @@
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");
+ seq_puts(m, "# pool packets-arrived sockets-enqueued threads-woken threads-timedout\n");
return 0;
}
- seq_printf(m, "%u %lu %lu %lu %lu %lu\n",
+ seq_printf(m, "%u %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;