alsa: automatically decrease watermark after a time of stability

2 files changed, 17 insertions, 15 deletions

diff --git a/src/pulsecore/rtpoll.c b/src/pulsecore/rtpoll.c
index 42708a8a..666cbc98 100644
--- a/src/pulsecore/rtpoll.c
+++ b/src/pulsecore/rtpoll.c
@@ -63,6 +63,7 @@ struct pa_rtpoll {
     pa_bool_t running:1;
     pa_bool_t rebuild_needed:1;
     pa_bool_t quit:1;
+    pa_bool_t timer_elapsed:1;
 
 #ifdef DEBUG_TIMING
     pa_usec_t timestamp;
@@ -94,26 +95,14 @@ PA_STATIC_FLIST_DECLARE(items, 0, pa_xfree);
 pa_rtpoll *pa_rtpoll_new(void) {
     pa_rtpoll *p;
 
-    p = pa_xnew(pa_rtpoll, 1);
+    p = pa_xnew0(pa_rtpoll, 1);
 
     p->n_pollfd_alloc = 32;
     p->pollfd = pa_xnew(struct pollfd, p->n_pollfd_alloc);
     p->pollfd2 = pa_xnew(struct pollfd, p->n_pollfd_alloc);
-    p->n_pollfd_used = 0;
-
-    pa_zero(p->next_elapse);
-    p->timer_enabled = FALSE;
-
-    p->running = FALSE;
-    p->scan_for_dead = FALSE;
-    p->rebuild_needed = FALSE;
-    p->quit = FALSE;
-
-    PA_LLIST_HEAD_INIT(pa_rtpoll_item, p->items);
 
 #ifdef DEBUG_TIMING
     p->timestamp = pa_rtclock_now();
-    p->slept = p->awake = 0;
 #endif
 
     return p;
@@ -229,6 +218,7 @@ int pa_rtpoll_run(pa_rtpoll *p, pa_bool_t wait_op) {
     pa_assert(!p->running);
 
     p->running = TRUE;
+    p->timer_elapsed = FALSE;
 
     /* First, let's do some work */
     for (i = p->items; i && i->priority < PA_RTPOLL_NEVER; i = i->next) {
@@ -286,7 +276,7 @@ int pa_rtpoll_run(pa_rtpoll *p, pa_bool_t wait_op) {
     if (p->rebuild_needed)
         rtpoll_rebuild(p);
 
-    memset(&timeout, 0, sizeof(timeout));
+    pa_zero(timeout);
 
     /* Calculate timeout */
     if (wait_op && !p->quit && p->timer_enabled) {
@@ -314,9 +304,11 @@ int pa_rtpoll_run(pa_rtpoll *p, pa_bool_t wait_op) {
         r = ppoll(p->pollfd, p->n_pollfd_used, (!wait_op || p->quit || p->timer_enabled) ? &ts : NULL, NULL);
     }
 #else
-        r = poll(p->pollfd, p->n_pollfd_used, (!wait_op || p->quit || p->timer_enabled) ? (int) ((timeout.tv_sec*1000) + (timeout.tv_usec / 1000)) : -1);
+    r = poll(p->pollfd, p->n_pollfd_used, (!wait_op || p->quit || p->timer_enabled) ? (int) ((timeout.tv_sec*1000) + (timeout.tv_usec / 1000)) : -1);
 #endif
 
+    p->timer_elapsed = r == 0;
+
 #ifdef DEBUG_TIMING
     {
         pa_usec_t now = pa_rtclock_now();
@@ -628,3 +620,9 @@ void pa_rtpoll_quit(pa_rtpoll *p) {
 
     p->quit = TRUE;
 }
+
+pa_bool_t pa_rtpoll_timer_elapsed(pa_rtpoll *p) {
+    pa_assert(p);
+
+    return p->timer_elapsed;
+}
diff --git a/src/pulsecore/rtpoll.h b/src/pulsecore/rtpoll.h
index d2d69cad..b2a87fca 100644
--- a/src/pulsecore/rtpoll.h
+++ b/src/pulsecore/rtpoll.h
@@ -73,6 +73,10 @@ void pa_rtpoll_set_timer_absolute(pa_rtpoll *p, pa_usec_t usec);
 void pa_rtpoll_set_timer_relative(pa_rtpoll *p, pa_usec_t usec);
 void pa_rtpoll_set_timer_disabled(pa_rtpoll *p);
 
+/* Return TRUE when the elapsed timer was the reason for
+ * the last pa_rtpoll_run() invocation to finish */
+pa_bool_t pa_rtpoll_timer_elapsed(pa_rtpoll *p);
+
 /* A new fd wakeup item for pa_rtpoll */
 pa_rtpoll_item *pa_rtpoll_item_new(pa_rtpoll *p, pa_rtpoll_priority_t prio, unsigned n_fds);
 void pa_rtpoll_item_free(pa_rtpoll_item *i);