sunrpc: new tracepoints around svc thread wakeups

Convert the svc_wake_up tracepoint into svc_pool_thread_event class.
Have it also record the pool id, and add new tracepoints for when the
thread is already running and for when there are no idle threads.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Author: jtlayton

include/trace/events/sunrpc.h

@@ -2123,22 +2123,35 @@ TRACE_EVENT(svc_xprt_accept,
 	)
 );
 
-TRACE_EVENT(svc_wake_up,
-	TP_PROTO(int pid),
+DECLARE_EVENT_CLASS(svc_pool_thread_event,
+	TP_PROTO(const struct svc_pool *pool, pid_t pid),
 
-	TP_ARGS(pid),
+	TP_ARGS(pool, pid),
 
 	TP_STRUCT__entry(
-		__field(int, pid)
+		__field(unsigned int, pool_id)
+		__field(pid_t, pid)
 	),
 
 	TP_fast_assign(
+		__entry->pool_id = pool->sp_id;
 		__entry->pid = pid;
 	),
 
-	TP_printk("pid=%d", __entry->pid)
+	TP_printk("pool=%u pid=%d", __entry->pool_id, __entry->pid)
 );
 
+#define DEFINE_SVC_POOL_THREAD_EVENT(name) \
+	DEFINE_EVENT(svc_pool_thread_event, svc_pool_thread_##name, \
+			TP_PROTO( \
+				const struct svc_pool *pool, pid_t pid \
+			), \
+			TP_ARGS(pool, pid))
+
+DEFINE_SVC_POOL_THREAD_EVENT(wake);
+DEFINE_SVC_POOL_THREAD_EVENT(running);
+DEFINE_SVC_POOL_THREAD_EVENT(noidle);
+
 TRACE_EVENT(svc_alloc_arg_err,
 	TP_PROTO(
 		unsigned int requested,

net/sunrpc/svc.c

@@ -751,14 +751,16 @@ void svc_pool_wake_idle_thread(struct svc_pool *pool)
 		WRITE_ONCE(rqstp->rq_qtime, ktime_get());
 		if (!task_is_running(rqstp->rq_task)) {
 			wake_up_process(rqstp->rq_task);
-			trace_svc_wake_up(rqstp->rq_task->pid);
+			trace_svc_pool_thread_wake(pool, rqstp->rq_task->pid);
 			percpu_counter_inc(&pool->sp_threads_woken);
+		} else {
+			trace_svc_pool_thread_running(pool, rqstp->rq_task->pid);
 		}
 		rcu_read_unlock();
 		return;
 	}
 	rcu_read_unlock();
-
+	trace_svc_pool_thread_noidle(pool, 0);
 }
 EXPORT_SYMBOL_GPL(svc_pool_wake_idle_thread);