commit 533bb72620933eddd232d41e171ab70ea0807e34
author Ravi Kumar Alamanda <ralama@codeaurora.org> Wed Sep 23 13:47:03 2015 -0700
committer Glenn Kasten <gkasten@google.com> Thu Sep 24 13:21:10 2015 -0700
tree eed72eeaf2e6dc5dcdf7319941af45c835ecc286
parent 88cbad341d2dd920ac74c2296f319482bd53a33d

hal: Add support for perf lock management

Acquire perf lock before starting an input or output
stream to optimize the cold start latency.

Bug: 22537514

Cherry-pick of CAF commit:
390bcf3edac3e0e38cf8163d1297f1b669117fe0

Change-Id: Iacedde8ff8531f8857e516e2671acd62197556a0

hal/audio_hw.c

diff --git a/hal/audio_hw.c b/hal/audio_hw.c
index ca86d75..3b8d6e0 100644
--- a/hal/audio_hw.c
+++ b/hal/audio_hw.c
@@ -801,6 +801,9 @@
     uc_info->out_snd_device = SND_DEVICE_NONE;
 
     list_add_tail(&adev->usecase_list, &uc_info->list);
+
+    audio_extn_perf_lock_acquire();
+
     select_devices(adev, in->usecase);
 
     ALOGV("%s: Opening PCM device card_id(%d) device_id(%d), channels %d",
@@ -835,12 +838,16 @@
 
     ALOGV("%s: pcm_prepare start", __func__);
     pcm_prepare(in->pcm);
+
+    audio_extn_perf_lock_release();
+
     ALOGV("%s: exit", __func__);
 
     return ret;
 
 error_open:
     stop_input_stream(in);
+    audio_extn_perf_lock_release();
 
 error_config:
     adev->active_input = NULL;
@@ -1153,6 +1160,8 @@
 
     list_add_tail(&adev->usecase_list, &uc_info->list);
 
+    audio_extn_perf_lock_acquire();
+
     select_devices(adev, out->usecase);
 
     audio_extn_extspk_update(adev->extspk);
@@ -1209,9 +1218,11 @@
         if (adev->offload_effects_start_output != NULL)
             adev->offload_effects_start_output(out->handle, out->pcm_device_id);
     }
+    audio_extn_perf_lock_release();
     ALOGV("%s: exit", __func__);
     return 0;
 error_open:
+    audio_extn_perf_lock_release();
     stop_output_stream(out);
 error_config:
     return ret;
@@ -2977,6 +2988,8 @@
     if (adev->adm_init)
         adev->adm_data = adev->adm_init();
 
+    audio_extn_perf_lock_init();
+
     ALOGV("%s: exit", __func__);
     return 0;
 }