diff options
| -rw-r--r-- | include/linux/sunrpc/svc.h | 11 | ||||
| -rw-r--r-- | net/sunrpc/svc.c | 14 | ||||
| -rw-r--r-- | net/sunrpc/svc_xprt.c | 38 |
3 files changed, 31 insertions, 32 deletions
diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h index ad4572630335..dafa362b4fdd 100644 --- a/include/linux/sunrpc/svc.h +++ b/include/linux/sunrpc/svc.h @@ -266,17 +266,6 @@ enum { RQ_DATA, /* request has data */ }; -/** - * svc_thread_busy - check if a thread as busy - * @rqstp: the thread which might be busy - * - * A thread is only busy when it is not an the idle list. - */ -static inline bool svc_thread_busy(const struct svc_rqst *rqstp) -{ - return !llist_on_list(&rqstp->rq_idle); -} - #define SVC_NET(rqst) (rqst->rq_xprt ? rqst->rq_xprt->xpt_net : rqst->rq_bc_net) /* diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c index 54ae6a569f6a..326592162af1 100644 --- a/net/sunrpc/svc.c +++ b/net/sunrpc/svc.c @@ -642,7 +642,6 @@ svc_rqst_alloc(struct svc_serv *serv, struct svc_pool *pool, int node) folio_batch_init(&rqstp->rq_fbatch); - init_llist_node(&rqstp->rq_idle); rqstp->rq_server = serv; rqstp->rq_pool = pool; @@ -704,17 +703,16 @@ void svc_pool_wake_idle_thread(struct svc_pool *pool) struct llist_node *ln; rcu_read_lock(); - spin_lock_bh(&pool->sp_lock); - ln = llist_del_first_init(&pool->sp_idle_threads); - spin_unlock_bh(&pool->sp_lock); + ln = READ_ONCE(pool->sp_idle_threads.first); if (ln) { rqstp = llist_entry(ln, struct svc_rqst, rq_idle); - WRITE_ONCE(rqstp->rq_qtime, ktime_get()); - wake_up_process(rqstp->rq_task); + if (!task_is_running(rqstp->rq_task)) { + wake_up_process(rqstp->rq_task); + trace_svc_wake_up(rqstp->rq_task->pid); + percpu_counter_inc(&pool->sp_threads_woken); + } rcu_read_unlock(); - percpu_counter_inc(&pool->sp_threads_woken); - trace_svc_wake_up(rqstp->rq_task->pid); return; } rcu_read_unlock(); diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c index 1b300a7889eb..75f66714e3a7 100644 --- a/net/sunrpc/svc_xprt.c +++ b/net/sunrpc/svc_xprt.c @@ -732,20 +732,19 @@ static void svc_thread_wait_for_work(struct svc_rqst *rqstp) if (svc_thread_should_sleep(rqstp)) { set_current_state(TASK_IDLE | TASK_FREEZABLE); llist_add(&rqstp->rq_idle, &pool->sp_idle_threads); + if (likely(svc_thread_should_sleep(rqstp))) + schedule(); - if (unlikely(!svc_thread_should_sleep(rqstp))) - /* Work just became available. This thread cannot simply - * choose not to sleep as it *must* wait until removed. - * So wake the first waiter - whether it is this - * thread or some other, it will get the work done. + while (!llist_del_first_this(&pool->sp_idle_threads, + &rqstp->rq_idle)) { + /* Work just became available. This thread can only + * handle it after removing rqstp from the idle + * list. If that attempt failed, some other thread + * must have queued itself after finding no + * work to do, so that thread has taken responsibly + * for this new work. This thread can safely sleep + * until woken again. */ - svc_pool_wake_idle_thread(pool); - - /* Since a thread cannot remove itself from an llist, - * schedule until someone else removes @rqstp from - * the idle list. - */ - while (!svc_thread_busy(rqstp)) { schedule(); set_current_state(TASK_IDLE | TASK_FREEZABLE); } @@ -835,6 +834,15 @@ out: svc_xprt_release(rqstp); } +static void svc_thread_wake_next(struct svc_rqst *rqstp) +{ + if (!svc_thread_should_sleep(rqstp)) + /* More work pending after I dequeued some, + * wake another worker + */ + svc_pool_wake_idle_thread(rqstp->rq_pool); +} + /** * svc_recv - Receive and process the next request on any transport * @rqstp: an idle RPC service thread @@ -854,13 +862,16 @@ void svc_recv(struct svc_rqst *rqstp) clear_bit(SP_TASK_PENDING, &pool->sp_flags); - if (svc_thread_should_stop(rqstp)) + if (svc_thread_should_stop(rqstp)) { + svc_thread_wake_next(rqstp); return; + } rqstp->rq_xprt = svc_xprt_dequeue(pool); if (rqstp->rq_xprt) { struct svc_xprt *xprt = rqstp->rq_xprt; + svc_thread_wake_next(rqstp); /* Normally we will wait up to 5 seconds for any required * cache information to be provided. When there are no * idle threads, we reduce the wait time. @@ -885,6 +896,7 @@ void svc_recv(struct svc_rqst *rqstp) if (req) { list_del(&req->rq_bc_list); spin_unlock_bh(&serv->sv_cb_lock); + svc_thread_wake_next(rqstp); svc_process_bc(req, rqstp); return; |