Merge "Refactor timestamp for input events" (96d2d6e9) · Commits · e / os / android_frameworks_native-old

services/inputflinger/EventHub.cpp

+20 −58

Original line number	Diff line number	Diff line
		@@ -40,7 +40,6 @@
		#include <hardware_legacy/power.h>

		#include <android-base/stringprintf.h>
		#include <cutils/properties.h>
		#include <openssl/sha.h>
		#include <utils/Log.h>
		#include <utils/Timers.h>
		@@ -109,6 +108,24 @@ static bool isV4lTouchNode(const char* name) {
		return strstr(name, "v4l-touch") == name;
		}

		static nsecs_t processEventTimestamp(const struct input_event& event) {
		// Use the time specified in the event instead of the current time
		// so that downstream code can get more accurate estimates of
		// event dispatch latency from the time the event is enqueued onto
		// the evdev client buffer.
		//
		// The event's timestamp fortuitously uses the same monotonic clock
		// time base as the rest of Android. The kernel event device driver
		// (drivers/input/evdev.c) obtains timestamps using ktime_get_ts().
		// The systemTime(SYSTEM_TIME_MONOTONIC) function we use everywhere
		// calls clock_gettime(CLOCK_MONOTONIC) which is implemented as a
		// system call that also queries ktime_get_ts().

		const nsecs_t inputEventTime = seconds_to_nanoseconds(event.time.tv_sec) +
		microseconds_to_nanoseconds(event.time.tv_usec);
		return inputEventTime;
		}

		// --- Global Functions ---

		uint32_t getAbsAxisUsage(int32_t axis, uint32_t deviceClasses) {
		@@ -485,8 +502,7 @@ status_t EventHub::mapKey(int32_t deviceId,

		// Check the key layout next.
		if (status != NO_ERROR && device->keyMap.haveKeyLayout()) {
		if (!device->keyMap.keyLayoutMap->mapKey(
		scanCode, usageCode, outKeycode, outFlags)) {
		if (!device->keyMap.keyLayoutMap->mapKey(scanCode, usageCode, outKeycode, outFlags)) {
		status = NO_ERROR;
		}
		}
		@@ -886,61 +902,7 @@ size_t EventHub::getEvents(int timeoutMillis, RawEvent* buffer, size_t bufferSiz
		size_t count = size_t(readSize) / sizeof(struct input_event);
		for (size_t i = 0; i < count; i++) {
		struct input_event& iev = readBuffer[i];
		ALOGV("%s got: time=%d.%06d, type=%d, code=%d, value=%d",
		device->path.c_str(),
		(int) iev.time.tv_sec, (int) iev.time.tv_usec,
		iev.type, iev.code, iev.value);

		// Use the time specified in the event instead of the current time
		// so that downstream code can get more accurate estimates of
		// event dispatch latency from the time the event is enqueued onto
		// the evdev client buffer.
		//
		// The event's timestamp fortuitously uses the same monotonic clock
		// time base as the rest of Android. The kernel event device driver
		// (drivers/input/evdev.c) obtains timestamps using ktime_get_ts().
		// The systemTime(SYSTEM_TIME_MONOTONIC) function we use everywhere
		// calls clock_gettime(CLOCK_MONOTONIC) which is implemented as a
		// system call that also queries ktime_get_ts().
		event->when = nsecs_t(iev.time.tv_sec) * 1000000000LL
		+ nsecs_t(iev.time.tv_usec) * 1000LL;
		ALOGV("event time %" PRId64 ", now %" PRId64, event->when, now);

		// Bug 7291243: Add a guard in case the kernel generates timestamps
		// that appear to be far into the future because they were generated
		// using the wrong clock source.
		//
		// This can happen because when the input device is initially opened
		// it has a default clock source of CLOCK_REALTIME. Any input events
		// enqueued right after the device is opened will have timestamps
		// generated using CLOCK_REALTIME. We later set the clock source
		// to CLOCK_MONOTONIC but it is already too late.
		//
		// Invalid input event timestamps can result in ANRs, crashes and
		// and other issues that are hard to track down. We must not let them
		// propagate through the system.
		//
		// Log a warning so that we notice the problem and recover gracefully.
		if (event->when >= now + 10 * 1000000000LL) {
		// Double-check. Time may have moved on.
		nsecs_t time = systemTime(SYSTEM_TIME_MONOTONIC);
		if (event->when > time) {
		ALOGW("An input event from %s has a timestamp that appears to "
		"have been generated using the wrong clock source "
		"(expected CLOCK_MONOTONIC): "
		"event time %" PRId64 ", current time %" PRId64
		", call time %" PRId64 ". "
		"Using current time instead.",
		device->path.c_str(), event->when, time, now);
		event->when = time;
		} else {
		ALOGV("Event time is ok but failed the fast path and required "
		"an extra call to systemTime: "
		"event time %" PRId64 ", current time %" PRId64
		", call time %" PRId64 ".",
		event->when, time, now);
		}
		}
		event->when = processEventTimestamp(iev);
		event->deviceId = deviceId;
		event->type = iev.type;
		event->code = iev.code;