blob: 59d74de9425abc3f72592943f509433216e70003 [file] [log] [blame]
/*
* Copyright (C) 2018 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#define LOG_TAG "TimeCheck"
#include <utils/Log.h>
#include <mediautils/TimeCheck.h>
#include <mediautils/EventLog.h>
#include "debuggerd/handler.h"
namespace android {
// Audio HAL server pids vector used to generate audio HAL processes tombstone
// when audioserver watchdog triggers.
// We use a lockless storage to avoid potential deadlocks in the context of watchdog
// trigger.
// Protection again simultaneous writes is not needed given one update takes place
// during AudioFlinger construction and other comes necessarily later once the IAudioFlinger
// interface is available.
// The use of an atomic index just guaranties that current vector is fully initialized
// when read.
/* static */
void TimeCheck::accessAudioHalPids(std::vector<pid_t>* pids, bool update) {
static constexpr int kNumAudioHalPidsVectors = 3;
static std::vector<pid_t> audioHalPids[kNumAudioHalPidsVectors];
static std::atomic<int> curAudioHalPids = 0;
if (update) {
audioHalPids[(curAudioHalPids + 1) % kNumAudioHalPidsVectors] = *pids;
curAudioHalPids++;
} else {
*pids = audioHalPids[curAudioHalPids];
}
}
/* static */
void TimeCheck::setAudioHalPids(const std::vector<pid_t>& pids) {
accessAudioHalPids(&(const_cast<std::vector<pid_t>&>(pids)), true);
}
/* static */
std::vector<pid_t> TimeCheck::getAudioHalPids() {
std::vector<pid_t> pids;
accessAudioHalPids(&pids, false);
return pids;
}
/* static */
sp<TimeCheck::TimeCheckThread> TimeCheck::getTimeCheckThread()
{
static sp<TimeCheck::TimeCheckThread> sTimeCheckThread = new TimeCheck::TimeCheckThread();
return sTimeCheckThread;
}
TimeCheck::TimeCheck(const char *tag, uint32_t timeoutMs)
: mEndTimeNs(getTimeCheckThread()->startMonitoring(tag, timeoutMs))
{
}
TimeCheck::~TimeCheck() {
getTimeCheckThread()->stopMonitoring(mEndTimeNs);
}
TimeCheck::TimeCheckThread::~TimeCheckThread()
{
AutoMutex _l(mMutex);
requestExit();
mMonitorRequests.clear();
mCond.signal();
}
nsecs_t TimeCheck::TimeCheckThread::startMonitoring(const char *tag, uint32_t timeoutMs) {
Mutex::Autolock _l(mMutex);
nsecs_t endTimeNs = systemTime() + milliseconds(timeoutMs);
for (; mMonitorRequests.indexOfKey(endTimeNs) >= 0; ++endTimeNs);
mMonitorRequests.add(endTimeNs, tag);
mCond.signal();
return endTimeNs;
}
void TimeCheck::TimeCheckThread::stopMonitoring(nsecs_t endTimeNs) {
Mutex::Autolock _l(mMutex);
mMonitorRequests.removeItem(endTimeNs);
mCond.signal();
}
bool TimeCheck::TimeCheckThread::threadLoop()
{
status_t status = TIMED_OUT;
{
AutoMutex _l(mMutex);
if (exitPending()) {
return false;
}
nsecs_t endTimeNs = INT64_MAX;
const char *tag = "<unspecified>";
// KeyedVector mMonitorRequests is ordered so take first entry as next timeout
if (mMonitorRequests.size() != 0) {
endTimeNs = mMonitorRequests.keyAt(0);
tag = mMonitorRequests.valueAt(0);
}
const nsecs_t waitTimeNs = endTimeNs - systemTime();
if (waitTimeNs > 0) {
status = mCond.waitRelative(mMutex, waitTimeNs);
}
if (status != NO_ERROR) {
// Generate audio HAL processes tombstones and allow time to complete
// before forcing restart
std::vector<pid_t> pids = getAudioHalPids();
if (pids.size() != 0) {
for (const auto& pid : pids) {
ALOGI("requesting tombstone for pid: %d", pid);
sigqueue(pid, DEBUGGER_SIGNAL, {.sival_int = 0});
}
sleep(1);
} else {
ALOGI("No HAL process pid available, skipping tombstones");
}
LOG_EVENT_STRING(LOGTAG_AUDIO_BINDER_TIMEOUT, tag);
LOG_ALWAYS_FATAL("TimeCheck timeout for %s", tag);
}
}
return true;
}
}; // namespace android