nsresult
nsSocketTransportService::DoPollIteration(TimeDuration *pollDuration)
{
SOCKET_LOG(("STS poll iter\n"));
int32_t i, count;
//
// poll loop
//
// walk active list backwards to see if any sockets should actually be
// idle, then walk the idle list backwards to see if any idle sockets
// should become active. take care to check only idle sockets that
// were idle to begin with ;-)
//
count = mIdleCount;
for (i=mActiveCount-1; i>=0; --i) {
//---
SOCKET_LOG((" active [%u] { handler=%p condition=%x pollflags=%hu }\n", i,
mActiveList[i].mHandler,
mActiveList[i].mHandler->mCondition,
mActiveList[i].mHandler->mPollFlags));
//---
if (NS_FAILED(mActiveList[i].mHandler->mCondition))
DetachSocket(mActiveList, &mActiveList[i]);
else {
uint16_t in_flags = mActiveList[i].mHandler->mPollFlags;
if (in_flags == 0)
MoveToIdleList(&mActiveList[i]);
else {
// update poll flags
mPollList[i+1].in_flags = in_flags;
mPollList[i+1].out_flags = 0;
}
}
}
for (i=count-1; i>=0; --i) {
//---
SOCKET_LOG((" idle [%u] { handler=%p condition=%x pollflags=%hu }\n", i,
mIdleList[i].mHandler,
mIdleList[i].mHandler->mCondition,
mIdleList[i].mHandler->mPollFlags));
//---
if (NS_FAILED(mIdleList[i].mHandler->mCondition))
DetachSocket(mIdleList, &mIdleList[i]);
else if (mIdleList[i].mHandler->mPollFlags != 0)
MoveToPollList(&mIdleList[i]);
}
SOCKET_LOG((" calling PR_Poll [active=%u idle=%u]\n", mActiveCount, mIdleCount));
#if defined(XP_WIN)
// 30 active connections is the historic limit before firefox 7's 256. A few
// windows systems have troubles with the higher limit, so actively probe a
// limit the first time we exceed 30.
if ((mActiveCount > 30) && !mProbedMaxCount)
ProbeMaxCount();
#endif
// Measures seconds spent while blocked on PR_Poll
uint32_t pollInterval = 0;
int32_t n = 0;
*pollDuration = 0;
if (!gIOService->IsNetTearingDown()) {
// Let's not do polling during shutdown.
n = Poll(&pollInterval, pollDuration);
}
if (n < 0) {
SOCKET_LOG((" PR_Poll error [%d] os error [%d]\n", PR_GetError(),
PR_GetOSError()));
}
else {
//
// service "active" sockets...
//
uint32_t numberOfOnSocketReadyCalls = 0;
for (i=0; i<int32_t(mActiveCount); ++i) {
PRPollDesc &desc = mPollList[i+1];
SocketContext &s = mActiveList[i];
if (n > 0 && desc.out_flags != 0) {
s.mElapsedTime = 0;
s.mHandler->OnSocketReady(desc.fd, desc.out_flags);
numberOfOnSocketReadyCalls++;
}
// check for timeout errors unless disabled...
else if (s.mHandler->mPollTimeout != UINT16_MAX) {
// update elapsed time counter
// (NOTE: We explicitly cast UINT16_MAX to be an unsigned value
// here -- otherwise, some compilers will treat it as signed,
// which makes them fire signed/unsigned-comparison build
// warnings for the comparison against 'pollInterval'.)
if (MOZ_UNLIKELY(pollInterval >
static_cast<uint32_t>(UINT16_MAX) -
s.mElapsedTime))
s.mElapsedTime = UINT16_MAX;
else
s.mElapsedTime += uint16_t(pollInterval);
// check for timeout expiration
if (s.mElapsedTime >= s.mHandler->mPollTimeout) {
s.mElapsedTime = 0;
s.mHandler->OnSocketReady(desc.fd, -1);
numberOfOnSocketReadyCalls++;
}
}
}
if (mTelemetryEnabledPref) {
Telemetry::Accumulate(
Telemetry::STS_NUMBER_OF_ONSOCKETREADY_CALLS,
numberOfOnSocketReadyCalls);
}
//
// check for "dead" sockets and remove them (need to do this in
// reverse order obviously).
//
for (i=mActiveCount-1; i>=0; --i) {
if (NS_FAILED(mActiveList[i].mHandler->mCondition))
DetachSocket(mActiveList, &mActiveList[i]);
}
if (n != 0 && (mPollList[0].out_flags & (PR_POLL_READ | PR_POLL_EXCEPT))) {
DebugMutexAutoLock lock(mLock);
// acknowledge pollable event (should not block)
if (mPollableEvent &&
((mPollList[0].out_flags & PR_POLL_EXCEPT) ||
!mPollableEvent->Clear())) {
// On Windows, the TCP loopback connection in the
// pollable event may become broken when a laptop
// switches between wired and wireless networks or
// wakes up from hibernation. We try to create a
// new pollable event. If that fails, we fall back
// on "busy wait".
NS_WARNING("Trying to repair mPollableEvent");
mPollableEvent.reset(new PollableEvent());
if (!mPollableEvent->Valid()) {
mPollableEvent = nullptr;
}
SOCKET_LOG(("running socket transport thread without "
"a pollable event now valid=%d", mPollableEvent->Valid()));
mPollList[0].fd = mPollableEvent ? mPollableEvent->PollableFD() : nullptr;
mPollList[0].in_flags = PR_POLL_READ | PR_POLL_EXCEPT;
mPollList[0].out_flags = 0;
}
}
}
return NS_OK;
}
NS_IMETHODIMP
nsSocketTransportService::Run()
{
LOG(("nsSocketTransportService::Run"));
gSocketThread = PR_GetCurrentThread();
//
// add thread event to poll list (mThreadEvent may be NULL)
//
mPollList[0].fd = mThreadEvent;
mPollList[0].in_flags = PR_POLL_READ;
mPollList[0].out_flags = 0;
PRInt32 i, count;
//
// poll loop
//
PRBool active = PR_TRUE;
while (active) {
//
// walk active list backwards to see if any sockets should actually be
// idle, then walk the idle list backwards to see if any idle sockets
// should become active. take care to check only idle sockets that
// were idle to begin with ;-)
//
count = mIdleCount;
for (i=mActiveCount-1; i>=0; --i) {
//---
LOG((" active [%u] { handler=%x condition=%x pollflags=%hu }\n", i,
mActiveList[i].mHandler,
mActiveList[i].mHandler->mCondition,
mActiveList[i].mHandler->mPollFlags));
//---
if (NS_FAILED(mActiveList[i].mHandler->mCondition))
DetachSocket(&mActiveList[i]);
else {
PRUint16 in_flags = mActiveList[i].mHandler->mPollFlags;
if (in_flags == 0)
MoveToIdleList(&mActiveList[i]);
else {
// update poll flags
mPollList[i+1].in_flags = in_flags;
mPollList[i+1].out_flags = 0;
}
}
}
for (i=count-1; i>=0; --i) {
//---
LOG((" idle [%u] { handler=%x condition=%x pollflags=%hu }\n", i,
mIdleList[i].mHandler,
mIdleList[i].mHandler->mCondition,
mIdleList[i].mHandler->mPollFlags));
//---
if (NS_FAILED(mIdleList[i].mHandler->mCondition))
DetachSocket(&mIdleList[i]);
else if (mIdleList[i].mHandler->mPollFlags != 0)
MoveToPollList(&mIdleList[i]);
}
LOG((" calling PR_Poll [active=%u idle=%u]\n", mActiveCount, mIdleCount));
// Measures seconds spent while blocked on PR_Poll
PRUint32 pollInterval;
PRInt32 n = Poll(&pollInterval);
if (n < 0) {
LOG((" PR_Poll error [%d]\n", PR_GetError()));
active = PR_FALSE;
}
else {
//
// service "active" sockets...
//
for (i=0; i<PRInt32(mActiveCount); ++i) {
PRPollDesc &desc = mPollList[i+1];
SocketContext &s = mActiveList[i];
if (n > 0 && desc.out_flags != 0) {
s.mElapsedTime = 0;
s.mHandler->OnSocketReady(desc.fd, desc.out_flags);
}
// check for timeout errors unless disabled...
else if (s.mHandler->mPollTimeout != PR_UINT16_MAX) {
// update elapsed time counter
if (NS_UNLIKELY(pollInterval > (PR_UINT16_MAX - s.mElapsedTime)))
s.mElapsedTime = PR_UINT16_MAX;
else
s.mElapsedTime += PRUint16(pollInterval);
// check for timeout expiration
if (s.mElapsedTime >= s.mHandler->mPollTimeout) {
s.mElapsedTime = 0;
s.mHandler->OnSocketReady(desc.fd, -1);
}
}
}
//
// check for "dead" sockets and remove them (need to do this in
// reverse order obviously).
//
for (i=mActiveCount-1; i>=0; --i) {
if (NS_FAILED(mActiveList[i].mHandler->mCondition))
DetachSocket(&mActiveList[i]);
}
//
// service the event queue (mPollList[0].fd == mThreadEvent)
//
if (n == 0)
active = ServiceEventQ();
else if (mPollList[0].out_flags == PR_POLL_READ) {
// acknowledge pollable event (wait should not block)
if (PR_WaitForPollableEvent(mThreadEvent) != PR_SUCCESS) {
// On Windows, the TCP loopback connection in the
// pollable event may become broken when a laptop
// switches between wired and wireless networks or
// wakes up from hibernation. We try to create a
// new pollable event. If that fails, we fall back
// on "busy wait".
{
nsAutoLock lock(mEventQLock);
PR_DestroyPollableEvent(mThreadEvent);
mThreadEvent = PR_NewPollableEvent();
}
if (!mThreadEvent) {
NS_WARNING("running socket transport thread without "
"a pollable event");
LOG(("running socket transport thread without "
"a pollable event"));
}
mPollList[0].fd = mThreadEvent;
// mPollList[0].in_flags was already set to PR_POLL_READ
// at the beginning of this method.
mPollList[0].out_flags = 0;
}
active = ServiceEventQ();
}
}
}
//
// shutdown thread
//
LOG(("shutting down socket transport thread...\n"));
mShuttingDown = PR_TRUE;
// detach any sockets
for (i=mActiveCount-1; i>=0; --i)
DetachSocket(&mActiveList[i]);
for (i=mIdleCount-1; i>=0; --i)
DetachSocket(&mIdleList[i]);
mShuttingDown = PR_FALSE;
// Final pass over the event queue. This makes sure that events posted by
// socket detach handlers get processed.
ServiceEventQ();
gSocketThread = nsnull;
return NS_OK;
}
