tree 5d0b86783cfa0a6c50fb176a2503d522ac35eb24
parent c2482f3ae25f413cff2e13443ac27ae81b76180f
author cdumez@apple.com <cdumez@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc> 1570897072 +0000
committer cdumez@apple.com <cdumez@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc> 1570897072 +0000

Clearing Website data for a given session should not shut down cached processes for other sessions
https://bugs.webkit.org/show_bug.cgi?id=202865
<rdar://problem/56202912>

Reviewed by Antti Koivisto.

When clearing Website data for a given data store, we now only clear cached processes
(either if BackForwardCache or WebProcessCache) if they are associated with this
particular data store. It is very wasteful otherwise.

* UIProcess/ProvisionalPageProxy.cpp:
(WebKit::ProvisionalPageProxy::~ProvisionalPageProxy):
* UIProcess/SuspendedPageProxy.cpp:
(WebKit::SuspendedPageProxy::~SuspendedPageProxy):
ProvisionalPageProxy & SuspendedPageProxy's destructors no longer call
WebProcessProxy::maybeShutdown() asynchronously. We now call maybeShutdown()
synchronously in WebProcessProxy::decrementSuspendedPageCount() and
WebProcessProxy::removeProvisionalPageProxy() instead. This makes things a
lot more predictable.

* UIProcess/WebBackForwardCache.cpp:
(WebKit::WebBackForwardCache::removeEntriesForSession):
Add new removeEntriesForSession() method to clear only back / forward cache
entries associated with a particular session.

(WebKit::WebBackForwardCache::clear):
Stop taking a parameter indicating if we allow the processes to enter the
process cache. Now that we call maybeShutdown() synchronously when destroying
a SuspendedPageProxy, we can simply allow the processes to enter the process
cache unconditionally. If the caller does not want this processes in the page
cache, they can clear the process cache afterwards.

* UIProcess/WebBackForwardCache.h:
* UIProcess/WebPageProxy.cpp:
(WebKit::WebPageProxy::receivedNavigationPolicyDecision):
Now that destroying a SuspendedPageProxy or a ProvisionalPageProxy may shutdown
their process synchronously, add a scope here to prevent shutdown of the process
for the duration of this scope, since we're about to use it for a navigation and
we don't want it to get shutdown, even if there is no longer anything using it.

(WebKit::WebPageProxy::continueNavigationInNewProcess):
Add new assertion and rename parameter for consistency.

* UIProcess/WebProcessPool.cpp:
(WebKit::WebProcessPool::handleMemoryPressureWarning):

* UIProcess/WebProcessProxy.cpp:
(WebKit::WebProcessProxy::addProvisionalPageProxy):
Add new assertion.

(WebKit::WebProcessProxy::removeProvisionalPageProxy):
Call maybeShutDown() if this was the last provisional page.

(WebKit::WebProcessProxy::maybeShutDown):
Drop parameter indicating if we want to allow the process to enter the process
cache and allow caching unconditionally.

(WebKit::WebProcessProxy::canTerminateAuxiliaryProcess):
Prevent termination if there is a ScopePreventingShutdown.

(WebKit::WebProcessProxy::decrementSuspendedPageCount):
Call maybeShutDown() if this was the last suspended page.

* UIProcess/WebProcessProxy.h:
(WebKit::WebProcessProxy::ScopePreventingShutdown::ScopePreventingShutdown):
(WebKit::WebProcessProxy::ScopePreventingShutdown::~ScopePreventingShutdown):
(WebKit::WebProcessProxy::makeScopePreventingShutdown):
Add new facility to prevent shutdown of a process for the duration of the scope.

* UIProcess/WebsiteData/WebsiteDataStore.cpp:
(WebKit::WebsiteDataStore::removeData):
When removing website data, only clear cached processes if they are associated with
the current data store.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@251048 268f45cc-cd09-0410-ab3c-d52691b4dbfc