Revert of High resolution timer fix for Windows (https://codereview.chromium.org/395913006/)
Reason for revert:
This patch seems to make following browser_tests flakey
PPAPINaClNewlibTest.Graphics2D_FlushOffscreenUpdate
NetInternalsTest.netInternalsHSTSViewAddOverwrite
NetInternalsTest.netInternalsHSTSViewAddDelete
NetInternalsTest.netInternalsHSTSViewAddTwice
http://build.chromium.org/p/chromium.win/builders/XP%20Tests%20%282%29/builds/34734
http://build.chromium.org/p/chromium.win/builders/XP%20Tests%20%281%29/builds/32086
http://build.chromium.org/p/chromium.win/builders/Vista%20Tests%20%281%29/builds/47545
Original issue's description:
> This is jamesr@ code I am landing.
>
> On Windows the message pump code tried to manage the systemwide timer resolution to fire delayed tasks with better than 15ms resolution but it was buggy:
>
> 1- A short task that was not followed by any other task will leave the systemwide timer pegged to 1ms
>
> 2- After we decided to crank up the timer we would 'lease' the timer for 1 second, for no good reason.
>
> Both issues are detrimental to battery power.
>
> The source of both problems is that we tried to decide with incomplete information. This patch solves that by having 1 bit for each pending task that requires a high resolution timer and a sum of the number of tasks that require high res timers.
>
> BUG=153139
> TEST=included here, also see the bug for manual testing.
>
> Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=284625
TBR=jamesr@chromium.org,darin@chromium.org,cpu@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=153139
Review URL: https://codereview.chromium.org/407073004
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@284664 0039d316-1c4b-4281-b951-d872f2087c98
CrOS-Libchrome-Original-Commit: 318717747560914c8052a2d072d20d0542c16fb7
diff --git a/base/message_loop/message_loop.cc b/base/message_loop/message_loop.cc
index 2d05ef1..a7217eb 100644
--- a/base/message_loop/message_loop.cc
+++ b/base/message_loop/message_loop.cc
@@ -127,8 +127,6 @@
MessageLoop::MessageLoop(Type type)
: type_(type),
- pending_high_res_tasks_(0),
- in_high_res_mode_(false),
nestable_tasks_allowed_(true),
#if defined(OS_WIN)
os_modal_loop_(false),
@@ -143,8 +141,6 @@
MessageLoop::MessageLoop(scoped_ptr<MessagePump> pump)
: pump_(pump.Pass()),
type_(TYPE_CUSTOM),
- pending_high_res_tasks_(0),
- in_high_res_mode_(false),
nestable_tasks_allowed_(true),
#if defined(OS_WIN)
os_modal_loop_(false),
@@ -157,11 +153,8 @@
MessageLoop::~MessageLoop() {
DCHECK_EQ(this, current());
+
DCHECK(!run_loop_);
-#if defined(OS_WIN)
- if (in_high_res_mode_)
- Time::ActivateHighResolutionTimer(false);
-#endif
// Clean up any unprocessed tasks, but take care: deleting a task could
// result in the addition of more tasks (e.g., via DeleteSoon). We set a
@@ -376,8 +369,8 @@
return run_loop_ != NULL;
}
-bool MessageLoop::HasHighResolutionTasks() {
- return incoming_task_queue_->HasHighResolutionTasks();
+bool MessageLoop::IsHighResolutionTimerEnabledForTesting() {
+ return incoming_task_queue_->IsHighResolutionTimerEnabledForTesting();
}
bool MessageLoop::IsIdleForTesting() {
@@ -445,11 +438,6 @@
"src_file", pending_task.posted_from.file_name(),
"src_func", pending_task.posted_from.function_name());
- if (pending_task.is_high_res) {
- pending_high_res_tasks_--;
- CHECK(pending_high_res_tasks_ >= 0);
- }
-
DCHECK(nestable_tasks_allowed_);
// Execute the task and assume the worst: It is probably not reentrant.
nestable_tasks_allowed_ = false;
@@ -535,10 +523,8 @@
// |*work_queue| by waiting until the last minute (|*work_queue| is empty) to
// load. That reduces the number of locks-per-task significantly when our
// queues get large.
- if (work_queue_.empty()) {
- pending_high_res_tasks_ +=
- incoming_task_queue_->ReloadWorkQueue(&work_queue_);
- }
+ if (work_queue_.empty())
+ incoming_task_queue_->ReloadWorkQueue(&work_queue_);
}
void MessageLoop::ScheduleWork(bool was_empty) {
@@ -643,14 +629,6 @@
if (run_loop_->quit_when_idle_received_)
pump_->Quit();
- // We will now do a kernel wait for more tasks.
-#if defined(OS_WIN)
- // The Windows scheduler has by default ~15ms resolution. If we have high
- // resolution tasks pending we need to temporarity increase the systemwide
- // timer resolution to 1ms, and if we don't we need to go back to 15ms.
- in_high_res_mode_ = pending_high_res_tasks_ > 0;
- Time::ActivateHighResolutionTimer(in_high_res_mode_);
-#endif
return false;
}