From c743b4259c3af2c0637c307f08a062d25fa3c99f Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Tue, 18 Jul 2023 16:38:08 +1000 Subject: [PATCH] SUNRPC: remove timeout arg from svc_recv() Most svc threads have no interest in a timeout. nfsd sets it to 1 hour, but this is a wart of no significance. lockd uses the timeout so that it can call nlmsvc_retry_blocked(). It also sometimes calls svc_wake_up() to ensure this is called. So change lockd to be consistent and always use svc_wake_up() to trigger nlmsvc_retry_blocked() - using a timer instead of a timeout to svc_recv(). And change svc_recv() to not take a timeout arg. This makes the sp_threads_timedout counter always zero. Signed-off-by: NeilBrown Signed-off-by: Chuck Lever --- fs/lockd/svc.c | 14 +++++++++----- fs/lockd/svclock.c | 5 +++-- fs/nfs/callback.c | 2 +- fs/nfsd/nfssvc.c | 2 +- include/linux/lockd/lockd.h | 4 +++- include/linux/sunrpc/svc.h | 1 - include/linux/sunrpc/svcsock.h | 2 +- net/sunrpc/svc.c | 2 -- net/sunrpc/svc_xprt.c | 34 ++++++++++++++++------------------ 9 files changed, 34 insertions(+), 32 deletions(-) diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c index cf4ff7d..ef3f77a5 100644 --- a/fs/lockd/svc.c +++ b/fs/lockd/svc.c @@ -56,6 +56,12 @@ static unsigned int nlmsvc_users; static struct svc_serv *nlmsvc_serv; unsigned long nlmsvc_timeout; +static void nlmsvc_request_retry(struct timer_list *tl) +{ + svc_wake_up(nlmsvc_serv); +} +DEFINE_TIMER(nlmsvc_retry, nlmsvc_request_retry); + unsigned int lockd_net_id; /* @@ -130,14 +136,11 @@ lockd(void *vrqstp) * NFS mount or NFS daemon has gone away. */ while (!kthread_should_stop()) { - long timeout = MAX_SCHEDULE_TIMEOUT; - /* update sv_maxconn if it has changed */ rqstp->rq_server->sv_maxconn = nlm_max_connections; - timeout = nlmsvc_retry_blocked(); - - svc_recv(rqstp, timeout); + nlmsvc_retry_blocked(); + svc_recv(rqstp); } if (nlmsvc_ops) nlmsvc_invalidate_all(); @@ -371,6 +374,7 @@ static void lockd_put(void) #endif svc_set_num_threads(nlmsvc_serv, NULL, 0); + timer_delete_sync(&nlmsvc_retry); nlmsvc_serv = NULL; dprintk("lockd_down: service destroyed\n"); } diff --git a/fs/lockd/svclock.c b/fs/lockd/svclock.c index 28abec5..43aeba9 100644 --- a/fs/lockd/svclock.c +++ b/fs/lockd/svclock.c @@ -1019,7 +1019,7 @@ retry_deferred_block(struct nlm_block *block) * picks up locks that can be granted, or grant notifications that must * be retransmitted. */ -unsigned long +void nlmsvc_retry_blocked(void) { unsigned long timeout = MAX_SCHEDULE_TIMEOUT; @@ -1049,5 +1049,6 @@ nlmsvc_retry_blocked(void) } spin_unlock(&nlm_blocked_lock); - return timeout; + if (timeout < MAX_SCHEDULE_TIMEOUT) + mod_timer(&nlmsvc_retry, jiffies + timeout); } diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c index 54155b4..39a0ba7 100644 --- a/fs/nfs/callback.c +++ b/fs/nfs/callback.c @@ -79,7 +79,7 @@ nfs4_callback_svc(void *vrqstp) set_freezable(); while (!kthread_freezable_should_stop(NULL)) - svc_recv(rqstp, MAX_SCHEDULE_TIMEOUT); + svc_recv(rqstp); svc_exit_thread(rqstp); return 0; diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c index 4c0ab10..1582af3 100644 --- a/fs/nfsd/nfssvc.c +++ b/fs/nfsd/nfssvc.c @@ -961,7 +961,7 @@ nfsd(void *vrqstp) /* Update sv_maxconn if it has changed */ rqstp->rq_server->sv_maxconn = nn->max_connections; - svc_recv(rqstp, 60*60*HZ); + svc_recv(rqstp); validate_process_creds(); } diff --git a/include/linux/lockd/lockd.h b/include/linux/lockd/lockd.h index f42594a..0f016d6 100644 --- a/include/linux/lockd/lockd.h +++ b/include/linux/lockd/lockd.h @@ -204,6 +204,8 @@ extern unsigned long nlmsvc_timeout; extern bool nsm_use_hostnames; extern u32 nsm_local_state; +extern struct timer_list nlmsvc_retry; + /* * Lockd client functions */ @@ -280,7 +282,7 @@ __be32 nlmsvc_testlock(struct svc_rqst *, struct nlm_file *, struct nlm_host *, struct nlm_lock *, struct nlm_lock *, struct nlm_cookie *); __be32 nlmsvc_cancel_blocked(struct net *net, struct nlm_file *, struct nlm_lock *); -unsigned long nlmsvc_retry_blocked(void); +void nlmsvc_retry_blocked(void); void nlmsvc_traverse_blocks(struct nlm_host *, struct nlm_file *, nlm_host_match_fn_t match); void nlmsvc_grant_reply(struct nlm_cookie *, __be32); diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h index 2230148..b206fdd 100644 --- a/include/linux/sunrpc/svc.h +++ b/include/linux/sunrpc/svc.h @@ -41,7 +41,6 @@ struct svc_pool { /* statistics on pool operation */ struct percpu_counter sp_sockets_queued; struct percpu_counter sp_threads_woken; - struct percpu_counter sp_threads_timedout; #define SP_TASK_PENDING (0) /* still work to do even if no * xprt is queued. */ diff --git a/include/linux/sunrpc/svcsock.h b/include/linux/sunrpc/svcsock.h index c0ddd33..d4a173c 100644 --- a/include/linux/sunrpc/svcsock.h +++ b/include/linux/sunrpc/svcsock.h @@ -57,7 +57,7 @@ static inline u32 svc_sock_final_rec(struct svc_sock *svsk) * Function prototypes. */ void svc_close_net(struct svc_serv *, struct net *); -void svc_recv(struct svc_rqst *, long); +void svc_recv(struct svc_rqst *rqstp); void svc_send(struct svc_rqst *rqstp); void svc_drop(struct svc_rqst *); void svc_sock_update_bufs(struct svc_serv *serv); diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c index c69896c..030f8c7 100644 --- a/net/sunrpc/svc.c +++ b/net/sunrpc/svc.c @@ -515,7 +515,6 @@ __svc_create(struct svc_program *prog, unsigned int bufsize, int npools, percpu_counter_init(&pool->sp_sockets_queued, 0, GFP_KERNEL); percpu_counter_init(&pool->sp_threads_woken, 0, GFP_KERNEL); - percpu_counter_init(&pool->sp_threads_timedout, 0, GFP_KERNEL); } return serv; @@ -590,7 +589,6 @@ svc_destroy(struct kref *ref) percpu_counter_destroy(&pool->sp_sockets_queued); percpu_counter_destroy(&pool->sp_threads_woken); - percpu_counter_destroy(&pool->sp_threads_timedout); } kfree(serv->sv_pools); kfree(serv); diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c index d7d6914..9bdcdd8 100644 --- a/net/sunrpc/svc_xprt.c +++ b/net/sunrpc/svc_xprt.c @@ -750,10 +750,9 @@ rqst_should_sleep(struct svc_rqst *rqstp) return true; } -static struct svc_xprt *svc_get_next_xprt(struct svc_rqst *rqstp, long timeout) +static struct svc_xprt *svc_get_next_xprt(struct svc_rqst *rqstp) { struct svc_pool *pool = rqstp->rq_pool; - long time_left = 0; /* rq_xprt should be clear on entry */ WARN_ON_ONCE(rqstp->rq_xprt); @@ -769,7 +768,7 @@ static struct svc_xprt *svc_get_next_xprt(struct svc_rqst *rqstp, long timeout) smp_mb__after_atomic(); if (likely(rqst_should_sleep(rqstp))) - time_left = schedule_timeout(timeout); + schedule(); else __set_current_state(TASK_RUNNING); @@ -781,9 +780,6 @@ static struct svc_xprt *svc_get_next_xprt(struct svc_rqst *rqstp, long timeout) if (rqstp->rq_xprt) goto out_found; - if (!time_left) - percpu_counter_inc(&pool->sp_threads_timedout); - if (kthread_should_stop()) return NULL; return NULL; @@ -863,12 +859,15 @@ out: return len; } -/* - * Receive the next request on any transport. This code is carefully - * organised not to touch any cachelines in the shared svc_serv - * structure, only cachelines in the local svc_pool. +/** + * svc_recv - Receive and process the next request on any transport + * @rqstp: an idle RPC service thread + * + * This code is carefully organised not to touch any cachelines in + * the shared svc_serv structure, only cachelines in the local + * svc_pool. */ -void svc_recv(struct svc_rqst *rqstp, long timeout) +void svc_recv(struct svc_rqst *rqstp) { struct svc_xprt *xprt = NULL; struct svc_serv *serv = rqstp->rq_server; @@ -882,7 +881,7 @@ void svc_recv(struct svc_rqst *rqstp, long timeout) if (kthread_should_stop()) goto out; - xprt = svc_get_next_xprt(rqstp, timeout); + xprt = svc_get_next_xprt(rqstp); if (!xprt) goto out; @@ -1447,12 +1446,11 @@ static int svc_pool_stats_show(struct seq_file *m, void *p) return 0; } - seq_printf(m, "%u %llu %llu %llu %llu\n", - pool->sp_id, - percpu_counter_sum_positive(&pool->sp_sockets_queued), - percpu_counter_sum_positive(&pool->sp_sockets_queued), - percpu_counter_sum_positive(&pool->sp_threads_woken), - percpu_counter_sum_positive(&pool->sp_threads_timedout)); + seq_printf(m, "%u %llu %llu %llu 0\n", + pool->sp_id, + percpu_counter_sum_positive(&pool->sp_sockets_queued), + percpu_counter_sum_positive(&pool->sp_sockets_queued), + percpu_counter_sum_positive(&pool->sp_threads_woken)); return 0; } -- 2.7.4