Attempting to resolve a race condition with PowerMonitor.

ThreadSanitizer caught multiple instances where PowerMonitor::Get or PowerMonitor::Add/RemoveObserver were being called concurrently with the PowerMonitor constructor in the main thread. These functions access a process-global PowerMontior instance (g_power_monitor), which was not thread safe.

This change adds locks around PowerMonitor creation and deletion, and forces Add/RemoveObserver to be called in a threadsafe manner. It also removes the need to call PowerMonitor::Get.

BUG=268924

Review URL: https://codereview.chromium.org/179923006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@262018 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 2 insertions, 8 deletions

diff --git a/net/url_request/url_request_job.cc b/net/url_request/url_request_job.cc
index 31a0d50..1332669 100644
--- a/net/url_request/url_request_job.cc
+++ b/net/url_request/url_request_job.cc
@@ -36,9 +36,7 @@ URLRequestJob::URLRequestJob(URLRequest* request,
       deferred_redirect_status_code_(-1),
       network_delegate_(network_delegate),
       weak_factory_(this) {
-  base::PowerMonitor* power_monitor = base::PowerMonitor::Get();
-  if (power_monitor)
-    power_monitor->AddObserver(this);
+  base::PowerMonitor::AddObserver(this);
 }
 
 void URLRequestJob::SetUpload(UploadDataStream* upload) {
@@ -246,11 +244,7 @@ void URLRequestJob::OnSuspend() {
 void URLRequestJob::NotifyURLRequestDestroyed() {
 }
 
-URLRequestJob::~URLRequestJob() {
-  base::PowerMonitor* power_monitor = base::PowerMonitor::Get();
-  if (power_monitor)
-    power_monitor->RemoveObserver(this);
-}
+URLRequestJob::~URLRequestJob() { base::PowerMonitor::RemoveObserver(this); }
 
 void URLRequestJob::NotifyCertificateRequested(
     SSLCertRequestInfo* cert_request_info) {