commit 0ee6e3707aed5e89678c9daf6f457b4ebe07a292
author yongchun.li <yongchun.li@amlogic.com> Fri Aug 20 04:26:04 2021 -0700
committer yongchun.li <yongchun.li@amlogic.com> Mon Aug 23 19:48:26 2021 -0700
tree b0f5bf099b078cc5eb8bee8e97f129cf5d4d3823
parent a50b1e98a99962b9b9f4a6a59ff8897ba295efc9

avsync-lib: remove no reqired mutex and avoid blocking  [1/1]

PD#SWPL-53639

Problem:
For 60fps 4K content playing have frame freeze then drop occationally
it is due to display refresh thread was blocked and cannot be finished
in one VSync. optimized the possible blocking codes in that thread
to avoid schedule switch out

Solution:
*Removed no need mutex in pattern module
*Log use CLOCK_MONOTONIC instead of timeofdate to avoid possible
NTP adjustment check block.
*avsync lib time compare use CLOCK_MONOTONIC also.
*frame queue use rd/wr index to check fullbess instead of
fullness field to avoid mutex.

Verify:
NTS test case PLAY-DV-60FPS-HEAAC

Change-Id: I0703bc2f9455b3ad24d53951c9e0e025f4cc2cd8
Signed-off-by: yongchun.li <yongchun.li@amlogic.com>

src/queue.c

diff --git a/src/queue.c b/src/queue.c
index e3318c1..3317cf0 100644
--- a/src/queue.c
+++ b/src/queue.c
@@ -17,7 +17,6 @@
     int max_len;
     int ri; //read index
     int wi; //write index
-    int total_num;
     void **items;
 };
 
@@ -45,7 +44,6 @@
 
     q->max_len = max_len;
     q->ri = q->wi = 0;
-    q->total_num = 0;
     return q;
 }
 
@@ -62,16 +60,20 @@
 int queue_item(void *queue, void * item)
 {
     struct queue *q = queue;
+    int fullness;
 
-    if (!q || q->total_num == q->max_len)
+    if (!q)
         return -1;
+    fullness = q->wi - q->ri;
+    if (fullness < 0) fullness += q->max_len;
+    if (fullness >= q->max_len - 1)
+        return -1; // not enough space
+
     q->items[q->wi] = item;
     if (q->wi == q->max_len - 1)
         q->wi = 0;
     else
         q->wi++;
-    q->total_num++;
-
     return 0;
 }
 
@@ -79,10 +81,15 @@
 {
     struct queue *q = queue;
     int32_t index;
+    int fullness;
 
-    if (!q || !q->total_num || q->total_num <= cnt)
+    if (!q)
         return -1;
 
+    fullness = q->wi - q->ri;
+    if (fullness < 0) fullness += q->max_len;
+    if (fullness == 0 || fullness <= cnt)
+       return -1; //no enough to peek
     index = q->ri;
     index += cnt;
     if (index >= q->max_len)
@@ -95,24 +102,30 @@
 int dqueue_item(void *queue, void** p_item)
 {
     struct queue *q = queue;
+    int fullness;
 
-    if (!q || !q->total_num)
+    if (!q)
         return -1;
+    fullness = q->wi - q->ri;
+    if (fullness < 0) fullness += q->max_len;
+    if (fullness == 0)
+        return -1; //empty
     *p_item = q->items[q->ri];
     if (q->ri == q->max_len - 1)
         q->ri = 0;
     else
         q->ri++;
-    q->total_num--;
-
     return 0;
 }
 
 int queue_size(void *queue)
 {
     struct queue *q = queue;
+    int fullness;
 
     if (!q)
         return -1;
-    return q->total_num;
+    fullness = q->wi - q->ri;
+    if (fullness < 0) fullness += q->max_len;
+    return fullness;
 }