MEDIUM: tasks: Merge task_delete() and task_free() into task_destroy().

task_delete() was never used without calling task_free() just after, and
task_free() was only used on error pathes to destroy a just-created task,
so merge them into task_destroy(), that will remove the task from the
wait queue, and make sure the task is either destroyed immediately if it's
not in the run queue, or destroyed when it's supposed to run.

include/proto/applet.h

@@ -85,8 +85,7 @@ static inline struct appctx *appctx_new(struct applet *applet, unsigned long thr
  */
 static inline void __appctx_free(struct appctx *appctx)
 {
-	task_delete(appctx->t);
-	task_free(appctx->t);
+	task_destroy(appctx->t);
 	if (!LIST_ISEMPTY(&appctx->buffer_wait.list)) {
 		HA_SPIN_LOCK(BUF_WQ_LOCK, &buffer_wq_lock);
 		LIST_DEL(&appctx->buffer_wait.list);

include/proto/task.h

@@ -273,17 +273,6 @@ static inline void task_remove_from_tasklet_list(struct task *t)
 		__task_remove_from_tasklet_list(t);
 }
 
-/*
- * Unlinks the task and adjusts run queue stats.
- * A pointer to the task itself is returned.
- */
-static inline struct task *task_delete(struct task *t)
-{
-	task_unlink_wq(t);
-	task_unlink_rq(t);
-	return t;
-}
-
 /*
  * Initialize a new task. The bare minimum is performed (queue pointers and
  * state).  The task is returned. This function should not be used outside of
@@ -350,8 +339,15 @@ static inline void __task_free(struct task *t)
 	_HA_ATOMIC_SUB(&nb_tasks, 1);
 }
 
-static inline void task_free(struct task *t)
+static inline void task_destroy(struct task *t)
 {
+	task_unlink_wq(t);
+	/* We don't have to explicitely remove from the run queue.
+	 * If we are in the runqueue, the test below will set t->process
+	 * to NULL, and the task will be free'd when it'll be its turn
+	 * to run.
+	 */
+
 	/* There's no need to protect t->state with a lock, as the task
 	 * has to run on the current thread.
 	 */

src/checks.c

@@ -3301,8 +3301,7 @@ int init_email_alert(struct mailers *mls, struct proxy *p, char **err)
 		struct check        *check = &q->check;
 
 		if (check->task) {
-			task_delete(check->task);
-			task_free(check->task);
+			task_destroy(check->task);
 			check->task = NULL;
 		}
 		free_check(check);

src/dns.c

@@ -1841,8 +1841,7 @@ static void dns_deinit(void)
 
 		free(resolvers->id);
 		free((char *)resolvers->conf.file);
-		task_delete(resolvers->t);
-		task_free(resolvers->t);
+		task_destroy(resolvers->t);
 		LIST_DEL(&resolvers->list);
 		free(resolvers);
 	}

src/flt_spoe.c

@@ -1276,8 +1276,7 @@ spoe_release_appctx(struct appctx *appctx)
 
 	/* Destroy the task attached to this applet */
 	if (spoe_appctx->task) {
-		task_delete(spoe_appctx->task);
-		task_free(spoe_appctx->task);
+		task_destroy(spoe_appctx->task);
 	}
 
 	/* Notify all waiting streams */
@@ -2023,7 +2022,7 @@ spoe_create_appctx(struct spoe_config *conf)
  out_free_sess:
 	session_free(sess);
  out_free_spoe:
-	task_free(SPOE_APPCTX(appctx)->task);
+	task_destroy(SPOE_APPCTX(appctx)->task);
  out_free_spoe_appctx:
 	pool_free(pool_head_spoe_appctx, SPOE_APPCTX(appctx));
  out_free_appctx:

src/haproxy.c

@@ -2278,19 +2278,13 @@ void deinit(void)
 		while (s) {
 			s_next = s->next;
 
-			if (s->check.task) {
-				task_delete(s->check.task);
-				task_free(s->check.task);
-			}
-			if (s->agent.task) {
-				task_delete(s->agent.task);
-				task_free(s->agent.task);
-			}
+			if (s->check.task)
+				task_destroy(s->check.task);
+			if (s->agent.task)
+				task_destroy(s->agent.task);
 
-			if (s->warmup) {
-				task_delete(s->warmup);
-				task_free(s->warmup);
-			}
+			if (s->warmup)
+				task_destroy(s->warmup);
 
 			free(s->id);
 			free(s->cookie);
@@ -2352,7 +2346,7 @@ void deinit(void)
 
 		free_http_req_rules(&p->http_req_rules);
 		free_http_res_rules(&p->http_res_rules);
-		task_free(p->task);
+		task_destroy(p->task);
 
 		pool_destroy(p->req_cap_pool);
 		pool_destroy(p->rsp_cap_pool);
@@ -2398,8 +2392,8 @@ void deinit(void)
 	free(global.node);    global.node = NULL;
 	free(global.desc);    global.desc = NULL;
 	free(oldpids);        oldpids = NULL;
-	task_free(global_listener_queue_task); global_listener_queue_task = NULL;
-	task_free(idle_conn_task);
+	task_destroy(global_listener_queue_task); global_listener_queue_task = NULL;
+	task_destroy(idle_conn_task);
 	idle_conn_task = NULL;
 
 	list_for_each_entry_safe(log, logb, &global.logsrvs, list) {
@@ -3080,10 +3074,9 @@ int main(int argc, char **argv)
 			stop_proxy(curpeers->peers_fe);
 			/* disable this peer section so that it kills itself */
 			signal_unregister_handler(curpeers->sighandler);
-			task_delete(curpeers->sync_task);
-			task_free(curpeers->sync_task);
+			task_destroy(curpeers->sync_task);
 			curpeers->sync_task = NULL;
-			task_free(curpeers->peers_fe->task);
+			task_destroy(curpeers->peers_fe->task);
 			curpeers->peers_fe->task = NULL;
 			curpeers->peers_fe = NULL;
 		}

src/hlua.c

@@ -6185,8 +6185,7 @@ static struct task *hlua_process_task(struct task *task, void *context, unsigned
 	/* finished or yield */
 	case HLUA_E_OK:
 		hlua_ctx_destroy(hlua);
-		task_delete(task);
-		task_free(task);
+		task_destroy(task);
 		task = NULL;
 		break;
 
@@ -6199,8 +6198,7 @@ static struct task *hlua_process_task(struct task *task, void *context, unsigned
 	case HLUA_E_ERRMSG:
 		SEND_ERR(NULL, "Lua task: %s.\n", lua_tostring(hlua->T, -1));
 		hlua_ctx_destroy(hlua);
-		task_delete(task);
-		task_free(task);
+		task_destroy(task);
 		task = NULL;
 		break;
 
@@ -6208,8 +6206,7 @@ static struct task *hlua_process_task(struct task *task, void *context, unsigned
 	default:
 		SEND_ERR(NULL, "Lua task: unknown error.\n");
 		hlua_ctx_destroy(hlua);
-		task_delete(task);
-		task_free(task);
+		task_destroy(task);
 		task = NULL;
 		break;
 	}
@@ -7052,8 +7049,7 @@ error:
 
 static void hlua_applet_tcp_release(struct appctx *ctx)
 {
-	task_delete(ctx->ctx.hlua_apptcp.task);
-	task_free(ctx->ctx.hlua_apptcp.task);
+	task_destroy(ctx->ctx.hlua_apptcp.task);
 	ctx->ctx.hlua_apptcp.task = NULL;
 	hlua_ctx_destroy(ctx->ctx.hlua_apptcp.hlua);
 	ctx->ctx.hlua_apptcp.hlua = NULL;
@@ -7520,8 +7516,7 @@ static void hlua_applet_http_fct(struct appctx *ctx)
 
 static void hlua_applet_http_release(struct appctx *ctx)
 {
-	task_delete(ctx->ctx.hlua_apphttp.task);
-	task_free(ctx->ctx.hlua_apphttp.task);
+	task_destroy(ctx->ctx.hlua_apphttp.task);
 	ctx->ctx.hlua_apphttp.task = NULL;
 	hlua_ctx_destroy(ctx->ctx.hlua_apphttp.hlua);
 	ctx->ctx.hlua_apphttp.hlua = NULL;

src/mux_h1.c

@@ -432,7 +432,7 @@ static int h1_init(struct connection *conn, struct proxy *proxy, struct session
 
   fail:
 	if (t)
-		task_free(t);
+		task_destroy(t);
 	if (h1c->wait_event.task)
 		tasklet_free(h1c->wait_event.task);
 	pool_free(pool_head_h1c, h1c);
@@ -1953,8 +1953,7 @@ static struct task *h1_timeout_task(struct task *t, void *context, unsigned shor
 	if (!expired && h1c)
 		return t;
 
-	task_delete(t);
-	task_free(t);
+	task_destroy(t);
 
 	if (!h1c) {
 		/* resources were already deleted */

src/mux_h2.c

@@ -576,7 +576,7 @@ static int h2_init(struct connection *conn, struct proxy *prx, struct session *s
 	hpack_dht_free(h2c->ddht);
   fail:
 	if (t)
-		task_free(t);
+		task_destroy(t);
 	if (h2c->wait_event.task)
 		tasklet_free(h2c->wait_event.task);
 	pool_free(pool_head_h2c, h2c);
@@ -2925,8 +2925,7 @@ static struct task *h2_timeout_task(struct task *t, void *context, unsigned shor
 	if (!expired && h2c)
 		return t;
 
-	task_delete(t);
-	task_free(t);
+	task_destroy(t);
 
 	if (!h2c) {
 		/* resources were already deleted */

src/mworker.c

@@ -379,10 +379,9 @@ void mworker_cleanlisteners()
 		stop_proxy(curpeers->peers_fe);
 		/* disable this peer section so that it kills itself */
 		signal_unregister_handler(curpeers->sighandler);
-		task_delete(curpeers->sync_task);
-		task_free(curpeers->sync_task);
+		task_destroy(curpeers->sync_task);
 		curpeers->sync_task = NULL;
-		task_free(curpeers->peers_fe->task);
+		task_destroy(curpeers->peers_fe->task);
 		curpeers->peers_fe->task = NULL;
 		curpeers->peers_fe = NULL;
 	}

src/peers.c

@@ -2448,8 +2448,7 @@ static struct task *process_peer_sync(struct task * task, void *context, unsigne
 	if (!peers->peers_fe) {
 		/* this one was never started, kill it */
 		signal_unregister_handler(peers->sighandler);
-		task_delete(peers->sync_task);
-		task_free(peers->sync_task);
+		task_destroy(peers->sync_task);
 		peers->sync_task = NULL;
 		return NULL;
 	}

src/session.c

@@ -396,8 +396,7 @@ static void session_kill_embryonic(struct session *sess, unsigned short state)
 	conn_free(conn);
 	sess->origin = NULL;
 
-	task_delete(task);
-	task_free(task);
+	task_destroy(task);
 	session_free(sess);
 }
 
@@ -450,8 +449,7 @@ static int conn_complete_session(struct connection *conn)
 
 	/* the embryonic session's task is not needed anymore */
 	if (sess->task) {
-		task_delete(sess->task);
-		task_free(sess->task);
+		task_destroy(sess->task);
 		sess->task = NULL;
 	}
 

src/stream.c

@@ -333,7 +333,7 @@ struct stream *stream_new(struct session *sess, enum obj_type *origin)
 	/* Error unrolling */
  out_fail_accept:
 	flt_stream_release(s, 0);
-	task_free(t);
+	task_destroy(t);
 	tasklet_free(s->si[1].wait_event.task);
 	LIST_DEL(&s->list);
 out_fail_alloc_si1:
@@ -2616,8 +2616,7 @@ redo:
 
 	/* the task MUST not be in the run queue anymore */
 	stream_free(s);
-	task_delete(t);
-	task_free(t);
+	task_destroy(t);
 	return NULL;
 }
 

src/task.c

@@ -432,16 +432,14 @@ void mworker_cleantasks()
 	while (tmp_rq) {
 		t = eb32sc_entry(tmp_rq, struct task, rq);
 		tmp_rq = eb32sc_next(tmp_rq, MAX_THREADS_MASK);
-		task_delete(t);
-		task_free(t);
+		task_destroy(t);
 	}
 	/* cleanup the timers queue */
 	tmp_wq = eb32_first(&timers);
 	while (tmp_wq) {
 		t = eb32_entry(tmp_wq, struct task, wq);
 		tmp_wq = eb32_next(tmp_wq);
-		task_delete(t);
-		task_free(t);
+		task_destroy(t);
 	}
 #endif
 	/* clean the per thread run queue */
@@ -450,16 +448,14 @@ void mworker_cleantasks()
 		while (tmp_rq) {
 			t = eb32sc_entry(tmp_rq, struct task, rq);
 			tmp_rq = eb32sc_next(tmp_rq, MAX_THREADS_MASK);
-			task_delete(t);
-			task_free(t);
+			task_destroy(t);
 		}
 		/* cleanup the per thread timers queue */
 		tmp_wq = eb32_first(&task_per_thread[i].timers);
 		while (tmp_wq) {
 			t = eb32_entry(tmp_wq, struct task, wq);
 			tmp_wq = eb32_next(tmp_wq);
-			task_delete(t);
-			task_free(t);
+			task_destroy(t);
 		}
 	}
 }