From 1ea51bf519bdfc0e04daa88b8788f06105c5599b Mon Sep 17 00:00:00 2001
From: Jeff Brown <jeffbrown@google.com>
Date: Wed, 30 May 2012 19:17:47 -0700
Subject: [PATCH] Remove unused statistics code.

Bug: 6559630
Change-Id: Iacdf4bb4c1c125c09305cbd8cb443c7c80cfc010
---
 include/utils/Looper.h | 21 -------------
 libs/utils/Looper.cpp  | 68 ------------------------------------------
 2 files changed, 89 deletions(-)

diff --git a/include/utils/Looper.h b/include/utils/Looper.h
index 3c2905d59..96b971e97 100644
--- a/include/utils/Looper.h
+++ b/include/utils/Looper.h
@@ -27,9 +27,6 @@
 // When defined, uses epoll_wait() for polling, otherwise uses poll().
 #define LOOPER_USES_EPOLL
 
-// When defined, logs performance statistics for tuning and debugging purposes.
-//#define LOOPER_STATISTICS
-
 #ifdef LOOPER_USES_EPOLL
 #include <sys/epoll.h>
 #else
@@ -340,24 +337,6 @@ private:
     void wakeAndLock();
 #endif
 
-#ifdef LOOPER_STATISTICS
-    static const int SAMPLED_WAKE_CYCLES_TO_AGGREGATE = 100;
-    static const int SAMPLED_POLLS_TO_AGGREGATE = 1000;
-
-    nsecs_t mPendingWakeTime;
-    int mPendingWakeCount;
-
-    int mSampledWakeCycles;
-    int mSampledWakeCountSum;
-    nsecs_t mSampledWakeLatencySum;
-
-    int mSampledPolls;
-    int mSampledZeroPollCount;
-    int mSampledZeroPollLatencySum;
-    int mSampledTimeoutPollCount;
-    int mSampledTimeoutPollLatencySum;
-#endif
-
     // This state is only used privately by pollOnce and does not require a lock since
     // it runs on a single thread.
     Vector<Response> mResponses;
diff --git a/libs/utils/Looper.cpp b/libs/utils/Looper.cpp
index d1aa664bc..95db28db0 100644
--- a/libs/utils/Looper.cpp
+++ b/libs/utils/Looper.cpp
@@ -98,20 +98,6 @@ Looper::Looper(bool allowNonCallbacks) :
     mPolling = false;
     mWaiters = 0;
 #endif
-
-#ifdef LOOPER_STATISTICS
-    mPendingWakeTime = -1;
-    mPendingWakeCount = 0;
-    mSampledWakeCycles = 0;
-    mSampledWakeCountSum = 0;
-    mSampledWakeLatencySum = 0;
-
-    mSampledPolls = 0;
-    mSampledZeroPollCount = 0;
-    mSampledZeroPollLatencySum = 0;
-    mSampledTimeoutPollCount = 0;
-    mSampledTimeoutPollLatencySum = 0;
-#endif
 }
 
 Looper::~Looper() {
@@ -234,10 +220,6 @@ int Looper::pollInner(int timeoutMillis) {
     mResponses.clear();
     mResponseIndex = 0;
 
-#ifdef LOOPER_STATISTICS
-    nsecs_t pollStartTime = systemTime(SYSTEM_TIME_MONOTONIC);
-#endif
-
 #ifdef LOOPER_USES_EPOLL
     struct epoll_event eventItems[EPOLL_MAX_EVENTS];
     int eventCount = epoll_wait(mEpollFd, eventItems, EPOLL_MAX_EVENTS, timeoutMillis);
@@ -341,29 +323,6 @@ Done:
     }
 #endif
 
-#ifdef LOOPER_STATISTICS
-    nsecs_t pollEndTime = systemTime(SYSTEM_TIME_MONOTONIC);
-    mSampledPolls += 1;
-    if (timeoutMillis == 0) {
-        mSampledZeroPollCount += 1;
-        mSampledZeroPollLatencySum += pollEndTime - pollStartTime;
-    } else if (timeoutMillis > 0 && result == ALOOPER_POLL_TIMEOUT) {
-        mSampledTimeoutPollCount += 1;
-        mSampledTimeoutPollLatencySum += pollEndTime - pollStartTime
-                - milliseconds_to_nanoseconds(timeoutMillis);
-    }
-    if (mSampledPolls == SAMPLED_POLLS_TO_AGGREGATE) {
-        ALOGD("%p ~ poll latency statistics: %0.3fms zero timeout, %0.3fms non-zero timeout", this,
-                0.000001f * float(mSampledZeroPollLatencySum) / mSampledZeroPollCount,
-                0.000001f * float(mSampledTimeoutPollLatencySum) / mSampledTimeoutPollCount);
-        mSampledPolls = 0;
-        mSampledZeroPollCount = 0;
-        mSampledZeroPollLatencySum = 0;
-        mSampledTimeoutPollCount = 0;
-        mSampledTimeoutPollLatencySum = 0;
-    }
-#endif
-
     // Invoke pending message callbacks.
     mNextMessageUptime = LLONG_MAX;
     while (mMessageEnvelopes.size() != 0) {
@@ -454,13 +413,6 @@ void Looper::wake() {
     ALOGD("%p ~ wake", this);
 #endif
 
-#ifdef LOOPER_STATISTICS
-    // FIXME: Possible race with awoken() but this code is for testing only and is rarely enabled.
-    if (mPendingWakeCount++ == 0) {
-        mPendingWakeTime = systemTime(SYSTEM_TIME_MONOTONIC);
-    }
-#endif
-
     ssize_t nWrite;
     do {
         nWrite = write(mWakeWritePipeFd, "W", 1);
@@ -478,26 +430,6 @@ void Looper::awoken() {
     ALOGD("%p ~ awoken", this);
 #endif
 
-#ifdef LOOPER_STATISTICS
-    if (mPendingWakeCount == 0) {
-        ALOGD("%p ~ awoken: spurious!", this);
-    } else {
-        mSampledWakeCycles += 1;
-        mSampledWakeCountSum += mPendingWakeCount;
-        mSampledWakeLatencySum += systemTime(SYSTEM_TIME_MONOTONIC) - mPendingWakeTime;
-        mPendingWakeCount = 0;
-        mPendingWakeTime = -1;
-        if (mSampledWakeCycles == SAMPLED_WAKE_CYCLES_TO_AGGREGATE) {
-            ALOGD("%p ~ wake statistics: %0.3fms wake latency, %0.3f wakes per cycle", this,
-                    0.000001f * float(mSampledWakeLatencySum) / mSampledWakeCycles,
-                    float(mSampledWakeCountSum) / mSampledWakeCycles);
-            mSampledWakeCycles = 0;
-            mSampledWakeCountSum = 0;
-            mSampledWakeLatencySum = 0;
-        }
-    }
-#endif
-
     char buffer[16];
     ssize_t nRead;
     do {