From: Olivier Houchard <ohouchard@haproxy.com>
Date: Wed, 6 Jun 2018 12:22:03 +0000 (+0200)
Subject: MINOR: tasks: Don't define rqueue if we're building without threads.
X-Git-Tag: v1.9-dev1~211
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=b1ca58b245e8e1dec098c5c0a83e4c4fd7b77a6c;p=thirdparty%2Fhaproxy.git

MINOR: tasks: Don't define rqueue if we're building without threads.

To make sure we don't inadvertently insert task in the global runqueue,
while only the local runqueue is used without threads, make its definition
and usage conditional on USE_THREAD.
---

diff --git a/include/proto/task.h b/include/proto/task.h
index dc8a54481f..2662460989 100644
--- a/include/proto/task.h
+++ b/include/proto/task.h
@@ -93,7 +93,9 @@ extern struct pool_head *pool_head_tasklet;
 extern struct pool_head *pool_head_notification;
 extern THREAD_LOCAL struct task *curr_task; /* task currently running or NULL */
 extern THREAD_LOCAL struct eb32sc_node *rq_next; /* Next task to be potentially run */
+#ifdef USE_THREAD
 extern struct eb_root rqueue;      /* tree constituting the run queue */
+#endif
 extern struct eb_root rqueue_local[MAX_THREADS]; /* tree constituting the per-thread run queue */
 extern struct list task_list[MAX_THREADS]; /* List of tasks to be run, mixing tasks and tasklets */
 extern int task_list_size[MAX_THREADS]; /* Number of task sin the task_list */
diff --git a/src/task.c b/src/task.c
index 16c7232304..c961725a1c 100644
--- a/src/task.c
+++ b/src/task.c
@@ -49,9 +49,11 @@ __decl_hathreads(HA_SPINLOCK_T __attribute__((aligned(64))) rq_lock); /* spin lo
 __decl_hathreads(HA_SPINLOCK_T __attribute__((aligned(64))) wq_lock); /* spin lock related to wait queue */
 
 static struct eb_root timers;      /* sorted timers tree */
+#ifdef USE_THREAD
 struct eb_root rqueue;      /* tree constituting the run queue */
-struct eb_root rqueue_local[MAX_THREADS]; /* tree constituting the per-thread run queue */
 static int global_rqueue_size; /* Number of element sin the global runqueue */
+#endif
+struct eb_root rqueue_local[MAX_THREADS]; /* tree constituting the per-thread run queue */
 static int rqueue_size[MAX_THREADS]; /* Number of elements in the per-thread run queue */
 static unsigned int rqueue_ticks;  /* insertion count */
 
@@ -68,10 +70,13 @@ void __task_wakeup(struct task *t, struct eb_root *root)
 	void *expected = NULL;
 	int *rq_size;
 
+#ifdef USE_THREAD
 	if (root == &rqueue) {
 		rq_size = &global_rqueue_size;
 		HA_SPIN_LOCK(TASK_RQ_LOCK, &rq_lock);
-	} else {
+	} else
+#endif
+	{
 		int nb = root - &rqueue_local[0];
 		rq_size = &rqueue_size[nb];
 	}
@@ -80,8 +85,10 @@ void __task_wakeup(struct task *t, struct eb_root *root)
 	 */
 redo:
 	if (unlikely(!HA_ATOMIC_CAS(&t->rq.node.leaf_p, &expected, (void *)0x1))) {
+#ifdef USE_THREAD
 		if (root == &rqueue)
 			HA_SPIN_UNLOCK(TASK_RQ_LOCK, &rq_lock);
+#endif
 		return;
 	}
 	/* There's a small race condition, when running a task, the thread
@@ -104,8 +111,10 @@ redo:
 		state = (volatile unsigned short)(t->state);
 		if (unlikely(state != 0 && !(state & TASK_RUNNING)))
 			goto redo;
+#ifdef USE_THREAD
 		if (root == &rqueue)
 			HA_SPIN_UNLOCK(TASK_RQ_LOCK, &rq_lock);
+#endif
 		return;
 	}
 	HA_ATOMIC_ADD(&tasks_run_queue, 1);
@@ -124,10 +133,13 @@ redo:
 	}
 
 	eb32sc_insert(root, &t->rq, t->thread_mask);
+#ifdef USE_THREAD
 	if (root == &rqueue) {
 		global_rqueue_size++;
 		HA_SPIN_UNLOCK(TASK_RQ_LOCK, &rq_lock);
-	} else {
+	} else
+#endif
+	{
 		int nb = root - &rqueue_local[0];
 
 		rqueue_size[nb]++;
@@ -239,7 +251,9 @@ void process_runnable_tasks()
 {
 	struct task *t;
 	int max_processed;
+#ifdef USE_THREAD
 	uint64_t average = 0;
+#endif
 
 	tasks_run_queue_cur = tasks_run_queue; /* keep a copy for reporting */
 	nb_tasks_cur = nb_tasks;
@@ -253,6 +267,7 @@ void process_runnable_tasks()
 			return;
 		}
 
+#ifdef USE_THREAD
 		average = tasks_run_queue / global.nbthread;
 
 		/* Get some elements from the global run queue and put it in the
@@ -284,6 +299,7 @@ void process_runnable_tasks()
 			__task_unlink_rq(t);
 			__task_wakeup(t, &rqueue_local[tid]);
 		}
+#endif
 
 		HA_SPIN_UNLOCK(TASK_RQ_LOCK, &rq_lock);
 	} else {
@@ -361,8 +377,12 @@ void process_runnable_tasks()
 		if (t != NULL) {
 			state = HA_ATOMIC_AND(&t->state, ~TASK_RUNNING);
 			if (state)
+#ifdef USE_THREAD
 				__task_wakeup(t, (t->thread_mask == tid_bit) ?
 				    &rqueue_local[tid] : &rqueue);
+#else
+				__task_wakeup(t, &rqueue_local[tid]);
+#endif
 			else
 				task_queue(t);
 		}
@@ -382,7 +402,9 @@ int init_task()
 	int i;
 
 	memset(&timers, 0, sizeof(timers));
+#ifdef USE_THREAD
 	memset(&rqueue, 0, sizeof(rqueue));
+#endif
 	HA_SPIN_INIT(&wq_lock);
 	HA_SPIN_INIT(&rq_lock);
 	for (i = 0; i < MAX_THREADS; i++) {