From: Andre Noll <maan@systemlinux.org>
Date: Sun, 10 Oct 2010 19:32:58 +0000 (+0200)
Subject: audiod: Handle crashes of para_server more robustly.
X-Git-Tag: v0.4.5~32
X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=commitdiff_plain;h=fd09012ca62c214fb3e2f48935e658b885c967b6;hp=3db64b098184e08bfac7939775ad9db9ebfc72fb

audiod: Handle crashes of para_server more robustly.

In case para_server dies unexpectedly, para_audiod may still have a partial status
item in the buffer tree node of the client task which can lead to a busy loop.

Fix this by flushing the input queue and invalidate the current audio format to prevent
recreating a buffer tree before the status task resumes.

There is already flush_input_queue() in buffer_tree.c but that can't be called by audiod.c
as it is a static function. Make it public and rename it to btr_drain() which is shorter and
more to the point and has the usual btr_ prefix.
---

diff --git a/audiod.c b/audiod.c
index 668b0f74..89b160db 100644
--- a/audiod.c
+++ b/audiod.c
@@ -1222,6 +1222,8 @@ static void status_post_select(__a_unused struct sched *s, struct task *t)
 			st->min_iqs = sz + 1;
 		goto out;
 	}
+	btr_drain(st->btrn);
+	st->current_audio_format_num = -1;
 	if (tv_diff(now, &st->restart_barrier, NULL) < 0)
 		goto out;
 	if (st->clock_diff_count) { /* get status only one time */
diff --git a/buffer_tree.c b/buffer_tree.c
index 3f1cc716..bdcbec8d 100644
--- a/buffer_tree.c
+++ b/buffer_tree.c
@@ -660,9 +660,10 @@ void btr_consume(struct btr_node *btrn, size_t numbytes)
 	return btr_consume(btrn, sz);
 }
 
-static void flush_input_queue(struct btr_node *btrn)
+void btr_drain(struct btr_node *btrn)
 {
 	struct btr_buffer_reference *br, *tmp;
+
 	FOR_EACH_BUFFER_REF_SAFE(br, tmp, btrn)
 		btr_drop_buffer_reference(br);
 }
@@ -702,7 +703,7 @@ void btr_remove_node(struct btr_node *btrn)
 	PARA_NOTICE_LOG("removing btr node %s from buffer tree\n", btrn->name);
 	FOR_EACH_CHILD(ch, btrn)
 		ch->parent = NULL;
-	flush_input_queue(btrn);
+	btr_drain(btrn);
 	if (btrn->parent)
 		list_del(&btrn->node);
 }
diff --git a/buffer_tree.h b/buffer_tree.h
index 549f95a2..8bc8e602 100644
--- a/buffer_tree.h
+++ b/buffer_tree.h
@@ -202,3 +202,4 @@ int btr_node_status(struct btr_node *btrn, size_t min_iqs,
 		enum btr_node_type type);
 void btr_get_node_start(struct btr_node *btrn, struct timeval *tv);
 struct btr_node *btr_search_node(const char *name, struct btr_node *root);
+void btr_drain(struct btr_node *btrn);