core: Take samples from silence cache rather than write zeros

If the only stream to render from is muted take samples from the
silence cache. This should shrink memory/cache bandwidth. Again the
gain was not what I hoped for.

diff --git a/src/pulsecore/sink.c b/src/pulsecore/sink.c
index a7e952931b44b430f3026699afd99bb33138c189..5ac5086bff7104c66f45694d759f8f8140992c79 100644 (file)
--- a/src/pulsecore/sink.c
+++ b/src/pulsecore/sink.c
@@ -787,11 +787,17 @@ void pa_sink_render(pa_sink*s, size_t length, pa_memchunk *result) {
         pa_sw_cvolume_multiply(&volume, &s->thread_info.soft_volume, &info[0].volume);
 
         if (s->thread_info.soft_muted || !pa_cvolume_is_norm(&volume)) {
-            pa_memchunk_make_writable(result, 0);
-            if (s->thread_info.soft_muted || pa_cvolume_is_muted(&volume))
-                pa_silence_memchunk(result, &s->sample_spec);
-            else
+            if (s->thread_info.soft_muted || pa_cvolume_is_muted(&volume)) {
+                pa_memblock_unref(result->memblock);
+                pa_silence_memchunk_get(&s->core->silence_cache,
+                                        s->core->mempool,
+                                        result,
+                                        &s->sample_spec,
+                                        result->length);
+            } else {
+                pa_memchunk_make_writable(result, 0);
                 pa_volume_memchunk(result, &s->sample_spec, &volume);
+            }
         }
     } else {
         void *ptr;
@@ -968,13 +974,19 @@ void pa_sink_render_full(pa_sink *s, size_t length, pa_memchunk *result) {
 
        pa_sw_cvolume_multiply(&volume, &s->thread_info.soft_volume, &info[0].volume);
 
-       if (s->thread_info.soft_muted || !pa_cvolume_is_norm(&volume)) {
-            pa_memchunk_make_writable(result, length);
-            if (s->thread_info.soft_muted || pa_cvolume_is_muted(&volume))
-                pa_silence_memchunk(result, &s->sample_spec);
-            else
+        if (s->thread_info.soft_muted || !pa_cvolume_is_norm(&volume)) {
+            if (s->thread_info.soft_muted || pa_cvolume_is_muted(&volume)) {
+                pa_memblock_unref(result->memblock);
+                pa_silence_memchunk_get(&s->core->silence_cache,
+                                        s->core->mempool,
+                                        result,
+                                        &s->sample_spec,
+                                        result->length);
+            } else {
+                pa_memchunk_make_writable(result, length);
                 pa_volume_memchunk(result, &s->sample_spec, &volume);
-       }
+            }
+        }
     } else {
         void *ptr;