---

yaml --- r: 305800 b: refs/heads/master c: 92b862c h: refs/heads/master v: v3
git-mirror · May 14, 2012 · a5bc6e3 · a5bc6e3
1 parent 6a04f98
commit a5bc6e3
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Showing 3 changed files with 9 additions and 2 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: e9148dddc3c7b6121300319c3e31f9380d459be8
+refs/heads/master: 92b862c7d685f5971a954e6ded51891d4adc412b
diff --git a/trunk/sound/firewire/amdtp.c b/trunk/sound/firewire/amdtp.c
@@ -178,6 +178,7 @@ void amdtp_out_stream_pcm_prepare(struct amdtp_out_stream *s)
 	tasklet_kill(&s->period_tasklet);
 	s->pcm_buffer_pointer = 0;
 	s->pcm_period_pointer = 0;
+	s->pointer_flush = true;
 }
 EXPORT_SYMBOL(amdtp_out_stream_pcm_prepare);
 
@@ -393,6 +394,7 @@ static void queue_out_packet(struct amdtp_out_stream *s, unsigned int cycle)
 		s->pcm_period_pointer += data_blocks;
 		if (s->pcm_period_pointer >= pcm->runtime->period_size) {
 			s->pcm_period_pointer -= pcm->runtime->period_size;
+			s->pointer_flush = false;
 			tasklet_hi_schedule(&s->period_tasklet);
 		}
 	}
@@ -539,7 +541,11 @@ EXPORT_SYMBOL(amdtp_out_stream_start);
  */
 unsigned long amdtp_out_stream_pcm_pointer(struct amdtp_out_stream *s)
 {
-	fw_iso_context_flush_completions(s->context);
+	/* this optimization is allowed to be racy */
+	if (s->pointer_flush)
+		fw_iso_context_flush_completions(s->context);
+	else
+		s->pointer_flush = true;
 
 	return ACCESS_ONCE(s->pcm_buffer_pointer);
 }

diff --git a/trunk/sound/firewire/amdtp.h b/trunk/sound/firewire/amdtp.h
@@ -68,6 +68,7 @@ struct amdtp_out_stream {
 
 	unsigned int pcm_buffer_pointer;
 	unsigned int pcm_period_pointer;
+	bool pointer_flush;
 };
 
 int amdtp_out_stream_init(struct amdtp_out_stream *s, struct fw_unit *unit,