Bug 1604851, r=dragana

No need to optimize one lock here since telemetry tells us only 1 out of 1m request with alt-svc
https://searchfox.org/mozilla-central/rev/b243debf6235b050b42fd2eb615fdc729636ca6b/netwerk/protocol/http/nsHttpChannel.cpp#6670

Differential Revision: https://phabricator.services.mozilla.com/D57925

--HG--
extra : moz-landing-system : lando

netwerk/protocol/http/nsHttpHandler.cpp

@@ -294,6 +294,8 @@ nsHttpHandler::nsHttpHandler()
       mNextChannelId(1),
       mLastActiveTabLoadOptimizationLock(
           "nsHttpConnectionMgr::LastActiveTabLoadOptimization"),
+      mSpdyBlacklistLock(
+          "nsHttpHandler::SpdyBlacklist"),
       mThroughCaptivePortal(false) {
   LOG(("Creating nsHttpHandler [this=%p].\n", this));
 
@@ -2669,11 +2671,17 @@ bool nsHttpHandler::IsBeforeLastActiveTabLoadOptimization(
 }
 
 void nsHttpHandler::BlacklistSpdy(const nsHttpConnectionInfo* ci) {
+  MOZ_ASSERT(OnSocketThread(), "not on socket thread");
+
   mConnMgr->BlacklistSpdy(ci);
-  mBlacklistedSpdyOrigins.PutEntry(ci->GetOrigin());
+  if (!mBlacklistedSpdyOrigins.Contains(ci->GetOrigin())) {
+    MutexAutoLock lock(mSpdyBlacklistLock);
+    mBlacklistedSpdyOrigins.PutEntry(ci->GetOrigin());
+  }
 }
 
 bool nsHttpHandler::IsSpdyBlacklisted(const nsHttpConnectionInfo* ci) {
+  MutexAutoLock lock(mSpdyBlacklistLock);
   return mBlacklistedSpdyOrigins.Contains(ci->GetOrigin());
 }
 

netwerk/protocol/http/nsHttpHandler.h

@@ -771,6 +771,7 @@ class nsHttpHandler final : public nsIHttpProtocolHandler,
   Mutex mLastActiveTabLoadOptimizationLock;
   TimeStamp mLastActiveTabLoadOptimizationHit;
 
+  Mutex mSpdyBlacklistLock;
  public:
   MOZ_MUST_USE nsresult NewChannelId(uint64_t& channelId);