commit 35a268c23ad4b55307d010ab2187da1bc6ec1c94
author Naseer Ahmed <naseer@codeaurora.org> Tue Jun 24 19:07:13 2014 -0400
committer Naseer Ahmed <naseer@codeaurora.org> Thu Jul 03 18:51:04 2014 -0400
tree d665bb4ab57977527d166423da095a3b2871f8ab
parent a3f48596f3fb43df107eca27e0abb00634c3d71f

display: Dynamic debug logging via binder

Provides a way to enable/disable logs at runtime via binder.
The logs need to be enabled from a priviliged shell.

For example,
$ adb shell service call display.qservice 15 i32 0 i32 1

Here 15 is the integer code for DYNAMIC_DEBUG in IQService.h
The first parameter 0 is for DEBUG_ALL
The second parameter 1 is to enable.

Hence, this command enables all debug logs.

Another example - this command enables vsync logging
$ adb shell service call display.qservice 15 i32 2 i32 1

Change-Id: I13d5f397d9d03f0ac6a14d3a3c9098ed59fc62fd

libhwcomposer/hwc_qclient.cpp

diff --git a/libhwcomposer/hwc_qclient.cpp b/libhwcomposer/hwc_qclient.cpp
index 77215ca..892e9c0 100644
--- a/libhwcomposer/hwc_qclient.cpp
+++ b/libhwcomposer/hwc_qclient.cpp
@@ -31,6 +31,7 @@
 #include <IQService.h>
 #include <hwc_utils.h>
 #include <mdp_version.h>
+#include <hwc_mdpcomp.h>
 
 #define QCLIENT_DEBUG 0
 
@@ -213,6 +214,26 @@
     }
 }
 
+static void toggleDynamicDebug(hwc_context_t* ctx, const Parcel* inParcel) {
+    int debug_type = inParcel->readInt32();
+    bool enable = !!inParcel->readInt32();
+    ALOGD("%s: debug_type: %d enable:%d",
+            __FUNCTION__, debug_type, enable);
+    Locker::Autolock _sl(ctx->mDrawLock);
+    switch (debug_type) {
+        //break is ignored for DEBUG_ALL to toggle all of them at once
+        case IQService::DEBUG_ALL:
+        case IQService::DEBUG_MDPCOMP:
+            qhwc::MDPComp::dynamicDebug(enable);
+            if (debug_type != IQService::DEBUG_ALL)
+                break;
+        case IQService::DEBUG_VSYNC:
+            ctx->vstate.debug = enable;
+            if (debug_type != IQService::DEBUG_ALL)
+                break;
+    }
+}
+
 status_t QClient::notifyCallback(uint32_t command, const Parcel* inParcel,
         Parcel* outParcel) {
     status_t ret = NO_ERROR;
@@ -255,6 +276,9 @@
         case IQService::SET_VIEW_FRAME:
             setViewFrame(mHwcContext, inParcel);
             break;
+        case IQService::DYNAMIC_DEBUG:
+            toggleDynamicDebug(mHwcContext, inParcel);
+            break;
         default:
             ret = NO_ERROR;
     }