tei/MapLibreParticleLab
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

[android] Do not try to wake up the RunLoop if a wake is already pending

Browse Source 
Do not flood the RunLoop with wake up calls, potentially causing the
socket buffer to overflow.

Also, write calls are syscalls and will cause a context switch.
This commit is contained in:
Thiago Marcos P. Santos
2019-08-07 14:04:26 +03:00
parent 5722136680
commit 47f498e642
2 changed files with 12 additions and 5 deletions
Download Patch File Download Diff File Expand all files Collapse all files

16
platform/android/src/run_loop.cpp
View File

@@ -31,8 +31,10 @@ int looperCallbackNew(int fd, int, void* data) {
int buffer[1];
while (read(fd, buffer, sizeof(buffer)) > 0) {}
auto loop = reinterpret_cast<ALooper*>(data);
ALooper_wake(loop);
auto runLoopImpl = reinterpret_cast<RunLoop::Impl*>(data);
runLoopImpl->coalesce.clear();
ALooper_wake(runLoopImpl->loop);
return 1;
}
@@ -42,9 +44,9 @@ int looperCallbackDefault(int fd, int, void* data) {
while (read(fd, buffer, sizeof(buffer)) > 0) {}
auto runLoopImpl = reinterpret_cast<RunLoop::Impl*>(data);
auto runLoop = runLoopImpl->runLoop;
runLoop->runOnce();
runLoopImpl->coalesce.clear();
runLoopImpl->runLoop->runOnce();
if (!runLoopImpl->running) {
ALooper_wake(runLoopImpl->loop);
@@ -99,7 +101,7 @@ RunLoop::Impl::Impl(RunLoop* runLoop_, RunLoop::Type type) : runLoop(runLoop_) {
switch (type) {
case Type::New:
ret = ALooper_addFd(loop, fds[PIPE_OUT], ALOOPER_POLL_CALLBACK,
ALOOPER_EVENT_INPUT, looperCallbackNew, loop);
ALOOPER_EVENT_INPUT, looperCallbackNew, this);
break;
case Type::Default:
ret = ALooper_addFd(loop, fds[PIPE_OUT], ALOOPER_POLL_CALLBACK,
@@ -129,6 +131,10 @@ RunLoop::Impl::~Impl() {
}
void RunLoop::Impl::wake() {
if (coalesce.test_and_set(std::memory_order_acquire)) {
return;
}
if (write(fds[PIPE_IN], "\n", 1) == -1) {
throw std::runtime_error("Failed to write to file descriptor.");
}