Merge "Handle race between UID state and activty resume" into pi-dev (83657476) · Commits · e / os / android_frameworks_av

services/camera/libcameraservice/CameraService.cpp

+25 −1

Original line number	Original line	Diff line number	Diff line
	@@ -55,6 +55,7 @@
	#include <utils/Errors.h>		#include <utils/Errors.h>
	#include <utils/Log.h>		#include <utils/Log.h>
	#include <utils/String16.h>		#include <utils/String16.h>
			#include <utils/SystemClock.h>
	#include <utils/Trace.h>		#include <utils/Trace.h>
	#include <private/android_filesystem_config.h>		#include <private/android_filesystem_config.h>
	#include <system/camera_vendor_tags.h>		#include <system/camera_vendor_tags.h>
	@@ -2433,6 +2434,8 @@ bool CameraService::UidPolicy::isUidActive(uid_t uid, String16 callingPackage) {
	return isUidActiveLocked(uid, callingPackage);		return isUidActiveLocked(uid, callingPackage);
	}		}

			static const int kPollUidActiveTimeoutMillis = 50;

	bool CameraService::UidPolicy::isUidActiveLocked(uid_t uid, String16 callingPackage) {		bool CameraService::UidPolicy::isUidActiveLocked(uid_t uid, String16 callingPackage) {
	// Non-app UIDs are considered always active		// Non-app UIDs are considered always active
	// If activity manager is unreachable, assume everything is active		// If activity manager is unreachable, assume everything is active
	@@ -2452,7 +2455,28 @@ bool CameraService::UidPolicy::isUidActiveLocked(uid_t uid, String16 callingPack
	ActivityManager am;		ActivityManager am;
	// Okay to access with a lock held as UID changes are dispatched without		// Okay to access with a lock held as UID changes are dispatched without
	// a lock and we are a higher level component.		// a lock and we are a higher level component.
			int64_t startTimeMillis = 0;
			do {
			// TODO: Fix this b/109950150!
			// Okay this is a hack. There is a race between the UID turning active and
			// activity being resumed. The proper fix is very risky, so we temporary add
			// some polling which should happen pretty rarely anyway as the race is hard
			// to hit.
	active = am.isUidActive(uid, callingPackage);		active = am.isUidActive(uid, callingPackage);
			if (active) {
			break;
			}
			if (startTimeMillis <= 0) {
			startTimeMillis = uptimeMillis();
			}
			int64_t ellapsedTimeMillis = uptimeMillis() - startTimeMillis;
			int64_t remainingTimeMillis = kPollUidActiveTimeoutMillis - ellapsedTimeMillis;
			if (remainingTimeMillis <= 0) {
			break;
			}
			usleep(remainingTimeMillis * 1000);
			} while (true);

	if (active) {		if (active) {
	// Now that we found out the UID is actually active, cache that		// Now that we found out the UID is actually active, cache that
	mActiveUids.insert(uid);		mActiveUids.insert(uid);