From 21ead9ff3dc72604d89499a1da5a18cc193ec4ff Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Wed, 3 Jan 2018 15:38:49 -0500 Subject: [PATCH] SUNRPC: Micro-optimize __rpc_execute The common case: There are 13 to 14 actions per RPC, and tk_callback is non-NULL in only one of them. There's no need to store a NULL in the tk_callback field during each FSM step. This slightly improves throughput results in dbench and other multi- threaded benchmarks on my two-socket client on 56Gb InfiniBand, but will probably be inconsequential on slower systems. Signed-off-by: Chuck Lever Signed-off-by: Anna Schumaker --- net/sunrpc/sched.c | 24 +++++++++++------------- 1 file changed, 11 insertions(+), 13 deletions(-) diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c index c292a5e1a70c..896691afbb1a 100644 --- a/net/sunrpc/sched.c +++ b/net/sunrpc/sched.c @@ -755,21 +755,19 @@ static void __rpc_execute(struct rpc_task *task) void (*do_action)(struct rpc_task *); /* - * Execute any pending callback first. + * Perform the next FSM step or a pending callback. + * + * tk_action may be NULL if the task has been killed. + * In particular, note that rpc_killall_tasks may + * do this at any time, so beware when dereferencing. */ - do_action = task->tk_callback; - task->tk_callback = NULL; - if (do_action == NULL) { - /* - * Perform the next FSM step. - * tk_action may be NULL if the task has been killed. - * In particular, note that rpc_killall_tasks may - * do this at any time, so beware when dereferencing. - */ - do_action = task->tk_action; - if (do_action == NULL) - break; + do_action = task->tk_action; + if (task->tk_callback) { + do_action = task->tk_callback; + task->tk_callback = NULL; } + if (!do_action) + break; trace_rpc_task_run_action(task->tk_client, task, do_action); do_action(task); -- 2.30.2