From: Willy Tarreau <w@1wt.eu>
Date: Wed, 24 Jun 2020 08:17:29 +0000 (+0200)
Subject: MINOR: tasks: make run_tasks_from_lists() scan the queues itself
X-Git-Tag: v2.2-dev11~26
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=59153fef8659753e2d512d574b7107c5736d1920;p=thirdparty%2Fhaproxy.git

MINOR: tasks: make run_tasks_from_lists() scan the queues itself

Now process_runnable_tasks is responsible for calculating the budgets
for each queue, dequeuing from the tree, and calling run_tasks_from_lists().
This latter one scans the queues, picking tasks there and respecting budgets.
Note that its name was updated with a plural "s" for this reason.
---

diff --git a/include/haproxy/task.h b/include/haproxy/task.h
index 335baf9a84..4bc216f63b 100644
--- a/include/haproxy/task.h
+++ b/include/haproxy/task.h
@@ -116,7 +116,7 @@ struct work_list *work_list_create(int nbthread,
                                    struct task *(*fct)(struct task *, void *, unsigned short),
                                    void *arg);
 void work_list_destroy(struct work_list *work, int nbthread);
-int run_tasks_from_list(unsigned int queue, int max);
+unsigned int run_tasks_from_lists(unsigned int budgets[]);
 
 /*
  * This does 3 things :
diff --git a/src/debug.c b/src/debug.c
index b4475f38be..6f465910da 100644
--- a/src/debug.c
+++ b/src/debug.c
@@ -142,7 +142,7 @@ void ha_thread_dump(struct buffer *buf, int thr, int calling_tid)
 
 			if (dump == 2) {
 				/* dumping */
-				if (addr == run_poll_loop || addr == main || addr == run_tasks_from_list) {
+				if (addr == run_poll_loop || addr == main || addr == run_tasks_from_lists) {
 					dump = 3;
 					*buf = bak;
 					break;
diff --git a/src/task.c b/src/task.c
index 65d29c3331..22954adc22 100644
--- a/src/task.c
+++ b/src/task.c
@@ -318,30 +318,36 @@ int next_timer_expiry()
 	return ret;
 }
 
-/* Walks over tasklet list sched->tasklets[queue] and run at most <max> of
- * them. Returns the number of entries effectively processed (tasks and
- * tasklets merged). The count of tasks in the list for the current thread
- * is adjusted.
+/* Walks over tasklet lists sched->tasklets[0..TL_CLASSES-1] and run at most
+ * budget[TL_*] of them. Returns the number of entries effectively processed
+ * (tasks and tasklets merged). The count of tasks in the list for the current
+ * thread is adjusted.
  */
-int run_tasks_from_list(unsigned int queue, int max)
+unsigned int run_tasks_from_lists(unsigned int budgets[])
 {
 	struct task *(*process)(struct task *t, void *ctx, unsigned short state);
 	struct list *tl_queues = sched->tasklets;
 	struct task *t;
+	unsigned int done = 0;
+	unsigned int queue;
 	unsigned short state;
 	void *ctx;
-	int done = 0;
 
-	sched->current_queue = queue;
-	while (1) {
+	for (queue = 0; queue < TL_CLASSES;) {
+		sched->current_queue = queue;
+
 		if (LIST_ISEMPTY(&tl_queues[queue])) {
 			sched->tl_class_mask &= ~(1 << queue);
-			break;
+			queue++;
+			continue;
 		}
 
-		if (done >= max)
-			break;
+		if (!budgets[queue]) {
+			queue++;
+			continue;
+		}
 
+		budgets[queue]--;
 		t = (struct task *)LIST_ELEM(tl_queues[queue].n, struct tasklet *, list);
 		state = (t->state & (TASK_SHARED_WQ|TASK_SELF_WAKING));
 
@@ -564,10 +570,7 @@ void process_runnable_tasks()
 	}
 
 	/* execute tasklets in each queue */
-	for (queue = 0; queue < TL_CLASSES; queue++) {
-		if (max[queue] > 0)
-			max_processed -= run_tasks_from_list(queue, max[queue]);
-	}
+	max_processed -= run_tasks_from_lists(max);
 
 	/* some tasks may have woken other ones up */
 	if (max_processed > 0 && thread_has_tasks())