zqz/platform-external-webrtc
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Fix the binary layout of ProcessThreadImpl.

Browse Source 
We apparently hit an obscure problem on mac where seemingly an unaligned mutex causes memory corruption.
The effect was that the |modules_| list became corrupt and we crashed.  At this point I'm not exactly
sure what the alignment requirements are but for now, I've fixed up the layout in a way that doesn't cause these same issues.

I'm also changing auto->proper type at the request of drive by reviewers from my previous cl in the same file.

TBR=pbos@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/38989004

Cr-Commit-Position: refs/heads/master@{#8286}
git-svn-id: http://webrtc.googlecode.com/svn/trunk@8286 4adac7df-926f-26a2-2b94-8c16560cd09d
This commit is contained in:
tommi@webrtc.org
2015-02-08 00:48:10 +00:00
parent ec499beaf5
commit 103f3289b5
2 changed files with 37 additions and 19 deletions
Download Patch File Download Diff File Expand all files Collapse all files

27
webrtc/modules/utility/source/process_thread_impl.cc
View File

@ -88,24 +88,26 @@ void ProcessThreadImpl::WakeUp(Module* module) {
// Allowed to be called on any thread.
{
rtc::CritScope lock(&lock_);
ModuleCallback cb(module);
const auto& found = std::find(modules_.begin(), modules_.end(), cb);
DCHECK(found != modules_.end()) << "programmer error?";
(*found).next_callback = 0;
for (ModuleCallback& m : modules_) {
if (m.module == module)
m.next_callback = 0;
}
}
wake_up_->Set();
}
int32_t ProcessThreadImpl::RegisterModule(Module* module) {
// Allowed to be called on any thread.
DCHECK(module);
{
rtc::CritScope lock(&lock_);
// Only allow module to be registered once.
ModuleCallback cb(module);
if (std::find(modules_.begin(), modules_.end(), cb) != modules_.end())
return -1;
modules_.push_front(cb);
for (const ModuleCallback& mc : modules_) {
if (mc.module == module)
return -1;
}
modules_.push_back(ModuleCallback(module));
}
// Wake the thread calling ProcessThreadImpl::Process() to update the
@ -118,6 +120,7 @@ int32_t ProcessThreadImpl::RegisterModule(Module* module) {
int32_t ProcessThreadImpl::DeRegisterModule(const Module* module) {
// Allowed to be called on any thread.
DCHECK(module);
rtc::CritScope lock(&lock_);
modules_.remove_if([&module](const ModuleCallback& m) {
return m.module == module;
@ -137,7 +140,7 @@ bool ProcessThreadImpl::Process() {
rtc::CritScope lock(&lock_);
if (stop_)
return false;
for (auto& m : modules_) {
for (ModuleCallback& m : modules_) {
// TODO(tommi): Would be good to measure the time TimeUntilNextProcess
// takes and dcheck if it takes too long (e.g. >=10ms). Ideally this
// operation should not require taking a lock, so querying all modules
@ -150,7 +153,7 @@ bool ProcessThreadImpl::Process() {
// Use a new 'now' reference to calculate when the next callback
// should occur. We'll continue to use 'now' above for the baseline
// of calculating how long we should wait, to reduce variance.
auto new_now = TickTime::MillisecondTimestamp();
int64_t new_now = TickTime::MillisecondTimestamp();
m.next_callback = GetNextCallbackTime(m.module, new_now);
}
@ -159,7 +162,7 @@ bool ProcessThreadImpl::Process() {
}
}
auto time_to_wait = next_checkpoint - TickTime::MillisecondTimestamp();
int64_t time_to_wait = next_checkpoint - TickTime::MillisecondTimestamp();
if (time_to_wait > 0)
wake_up_->Wait(static_cast<unsigned long>(time_to_wait));