Implement ProcessReusePolicy for SiteInstances

content/browser/site_instance_impl.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/site_instance_impl.h"
 
 #include "base/memory/ptr_util.h"
 #include "content/browser/browsing_instance.h"
 #include "content/browser/child_process_security_policy_impl.h"
 #include "content/browser/frame_host/debug_urls.h"
 #include "content/browser/frame_host/frame_tree_node.h"
 #include "content/browser/renderer_host/render_process_host_impl.h"
 #include "content/browser/storage_partition_impl.h"
 #include "content/common/site_isolation_policy.h"
 #include "content/public/browser/content_browser_client.h"
 #include "content/public/browser/render_process_host_factory.h"
 #include "content/public/browser/web_ui_controller_factory.h"
 #include "content/public/common/url_constants.h"
 #include "net/base/registry_controlled_domains/registry_controlled_domain.h"
 
 namespace content {
 
-const RenderProcessHostFactory*
-    SiteInstanceImpl::g_render_process_host_factory_ = NULL;
 int32_t SiteInstanceImpl::next_site_instance_id_ = 1;
 
 SiteInstanceImpl::SiteInstanceImpl(BrowsingInstance* browsing_instance)
     : id_(next_site_instance_id_++),
       active_frame_count_(0),
       browsing_instance_(browsing_instance),
       process_(nullptr),
       has_site_(false),
-      is_default_subframe_site_instance_(false) {
+      process_reuse_policy_(
+          RenderProcessHostImpl::ProcessReusePolicy::DEFAULT) {
   DCHECK(browsing_instance);
 }
 
 SiteInstanceImpl::~SiteInstanceImpl() {
   GetContentClient()->browser()->SiteInstanceDeleting(this);
 
   if (process_)
     process_->RemoveObserver(this);
 
   // Now that no one is referencing us, we can safely remove ourselves from
@@ skipping 32 matching lines @@
       browsing_instance_->browser_context();
   if (has_site_ &&
       RenderProcessHost::ShouldUseProcessPerSite(browser_context, site_) &&
       RenderProcessHostImpl::GetProcessHostForSite(browser_context, site_)) {
     return true;
   }
 
   return false;
 }
 
-namespace {
-
-const void* const kDefaultSubframeProcessHostHolderKey =
-    &kDefaultSubframeProcessHostHolderKey;
-
-class DefaultSubframeProcessHostHolder : public base::SupportsUserData::Data,
-                                         public RenderProcessHostObserver {
- public:
-  explicit DefaultSubframeProcessHostHolder(BrowserContext* browser_context)
-      : browser_context_(browser_context) {}
-  ~DefaultSubframeProcessHostHolder() override {}
-
-  // Gets the correct render process to use for this SiteInstance.
-  RenderProcessHost* GetProcessHost(SiteInstance* site_instance,
-                                    bool is_for_guests_only) {
-    StoragePartition* default_partition =
-        BrowserContext::GetDefaultStoragePartition(browser_context_);
-    StoragePartition* partition =
-        BrowserContext::GetStoragePartition(browser_context_, site_instance);
-
-    // Is this the default storage partition? If it isn't, then just give it its
-    // own non-shared process.
-    if (partition != default_partition || is_for_guests_only) {
-      RenderProcessHostImpl* host = new RenderProcessHostImpl(
-          browser_context_, static_cast<StoragePartitionImpl*>(partition),
-          is_for_guests_only);
-      host->SetIsNeverSuitableForReuse();
-      return host;
-    }
-
-    if (host_) {
-      // If we already have a shared host for the default storage partition, use
-      // it.
-      return host_;
-    }
-
-    host_ = new RenderProcessHostImpl(
-        browser_context_, static_cast<StoragePartitionImpl*>(partition),
-        false /* for guests only */);
-    host_->SetIsNeverSuitableForReuse();
-    host_->AddObserver(this);
-
-    return host_;
-  }
-
-  void RenderProcessHostDestroyed(RenderProcessHost* host) override {
-    DCHECK_EQ(host_, host);
-    host_->RemoveObserver(this);
-    host_ = nullptr;
-  }
-
- private:
-  BrowserContext* browser_context_;
-
-  // The default subframe render process used for the default storage partition
-  // of this BrowserContext.
-  RenderProcessHostImpl* host_ = nullptr;
-};
-
-}  // namespace
-
-RenderProcessHost* SiteInstanceImpl::GetDefaultSubframeProcessHost(
-    BrowserContext* browser_context,
-    bool is_for_guests_only) {

[nasko, 2017/05/03 23:46:17]

Ok, I didn't realize this is code that just moved over when I read it as new in
the other file. I'm fine leaving it as is, since it is a move.

[clamy, 2017/05/04 15:56:19]

I did the modifications as requested in the other file before reading this
comment. I'm uploading them, let me know what you prefer.

-  DefaultSubframeProcessHostHolder* holder =
-      static_cast<DefaultSubframeProcessHostHolder*>(
-          browser_context->GetUserData(&kDefaultSubframeProcessHostHolderKey));
-  if (!holder) {
-    holder = new DefaultSubframeProcessHostHolder(browser_context);
-    browser_context->SetUserData(kDefaultSubframeProcessHostHolderKey,
-                                 base::WrapUnique(holder));
-  }
-
-  return holder->GetProcessHost(this, is_for_guests_only);
-}
-
 RenderProcessHost* SiteInstanceImpl::GetProcess() {
   // TODO(erikkay) It would be nice to ensure that the renderer type had been
   // properly set before we get here.  The default tab creation case winds up
   // with no site set at this point, so it will default to TYPE_NORMAL.  This
   // may not be correct, so we'll wind up potentially creating a process that
   // we then throw away, or worse sharing a process with the wrong process type.
   // See crbug.com/43448.
 
   // Create a new process if ours went away or was reused.
   if (!process_) {
     BrowserContext* browser_context = browsing_instance_->browser_context();
-    bool is_for_guests_only = site_.SchemeIs(kGuestScheme);
+    process_ = RenderProcessHostImpl::GetProcessHostForSiteInstance(
+        browser_context, this);
 
-    // If we should use process-per-site mode (either in general or for the
-    // given site), then look for an existing RenderProcessHost for the site.
-    bool use_process_per_site = has_site_ &&
-        RenderProcessHost::ShouldUseProcessPerSite(browser_context, site_);
-    if (use_process_per_site) {
-      process_ = RenderProcessHostImpl::GetProcessHostForSite(browser_context,
-                                                              site_);
-    }
-
-    if (!process_ && IsDefaultSubframeSiteInstance() &&
-        SiteIsolationPolicy::IsTopDocumentIsolationEnabled()) {
-      process_ =
-          GetDefaultSubframeProcessHost(browser_context, is_for_guests_only);
-    }
-
-    // If not (or if none found), see if we should reuse an existing process.
-    if (!process_ && RenderProcessHostImpl::ShouldTryToUseExistingProcessHost(
-            browser_context, site_)) {
-      process_ = RenderProcessHostImpl::GetExistingProcessHost(browser_context,
-                                                               site_);
-    }
-
-    // Otherwise (or if that fails), create a new one.
-    if (!process_) {
-      if (g_render_process_host_factory_) {
-        process_ = g_render_process_host_factory_->CreateRenderProcessHost(
-            browser_context, this);
-      } else {
-        StoragePartitionImpl* partition =
-            static_cast<StoragePartitionImpl*>(
-                BrowserContext::GetStoragePartition(browser_context, this));
-        process_ = new RenderProcessHostImpl(browser_context, partition,
-                                             is_for_guests_only);
-      }
-    }
     CHECK(process_);
     process_->AddObserver(this);
 
     // If we are using process-per-site, we need to register this process
     // for the current site so that we can find it again.  (If no site is set
     // at this time, we will register it in SetSite().)
-    if (use_process_per_site) {
+    if (process_reuse_policy_ ==
+            RenderProcessHostImpl::ProcessReusePolicy::PROCESS_PER_SITE &&
+        has_site_) {
       RenderProcessHostImpl::RegisterProcessHostForSite(browser_context,

[Charlie Reis, 2017/05/03 23:28:00]

Ah, I suppose there's still a fair amount needed before we can use
PROCESS_PER_SITE on a per-SiteInstance basis (e.g., for ServiceWorker), since
we'll also need to register sites in each RPH in all cases.  But that's fine to
do later-- the other description updates in the enum should still apply.

[clamy, 2017/05/04 15:56:19]

Indeed. The goal of this patch is to move the code in a state where it's easier
to modify.

                                                         process_, site_);
     }
 
     TRACE_EVENT2("navigation", "SiteInstanceImpl::GetProcess",
                  "site id", id_, "process id", process_->GetID());
     GetContentClient()->browser()->SiteInstanceGotProcess(this);
 
     if (has_site_)
       LockToOrigin();
   }
@@ skipping 17 matching lines @@
   has_site_ = true;
   BrowserContext* browser_context = browsing_instance_->browser_context();
   site_ = GetSiteForURL(browser_context, url);
 
   // Now that we have a site, register it with the BrowsingInstance.  This
   // ensures that we won't create another SiteInstance for this site within
   // the same BrowsingInstance, because all same-site pages within a
   // BrowsingInstance can script each other.
   browsing_instance_->RegisterSiteInstance(this);
 
+  // Update the process reuse policy based on the site.
+  bool should_use_process_per_site =
+      RenderProcessHost::ShouldUseProcessPerSite(browser_context, site_);
+  if (should_use_process_per_site) {
+    process_reuse_policy_ =
+        RenderProcessHostImpl::ProcessReusePolicy::PROCESS_PER_SITE;
+  }
+
   if (process_) {
     LockToOrigin();
 
     // Ensure the process is registered for this site if necessary.
-    if (RenderProcessHost::ShouldUseProcessPerSite(browser_context, site_)) {
+    if (should_use_process_per_site) {
       RenderProcessHostImpl::RegisterProcessHostForSite(
           browser_context, process_, site_);
     }
   }
 }
 
 const GURL& SiteInstanceImpl::GetSiteURL() const {
   return site_;
 }
 
@@ skipping 46 matching lines @@
 }
 
 bool SiteInstanceImpl::RequiresDedicatedProcess() {
   if (!has_site_)
     return false;
 
   return DoesSiteRequireDedicatedProcess(GetBrowserContext(), site_);
 }
 
 bool SiteInstanceImpl::IsDefaultSubframeSiteInstance() const {
-  return is_default_subframe_site_instance_;
+  return process_reuse_policy_ == RenderProcessHostImpl::ProcessReusePolicy::
+                                      USE_DEFAULT_SUBFRAME_INSTANCE;
 }
 
 void SiteInstanceImpl::IncrementActiveFrameCount() {
   active_frame_count_++;
 }
 
 void SiteInstanceImpl::DecrementActiveFrameCount() {
   if (--active_frame_count_ == 0) {
     for (auto& observer : observers_)
       observer.ActiveFrameCountIsZero(this);
   }
 }
 
 void SiteInstanceImpl::IncrementRelatedActiveContentsCount() {
   browsing_instance_->increment_active_contents_count();
 }
 
 void SiteInstanceImpl::DecrementRelatedActiveContentsCount() {
   browsing_instance_->decrement_active_contents_count();
 }
 
 void SiteInstanceImpl::AddObserver(Observer* observer) {
   observers_.AddObserver(observer);
 }
 
 void SiteInstanceImpl::RemoveObserver(Observer* observer) {
   observers_.RemoveObserver(observer);
 }
 
-void SiteInstanceImpl::set_render_process_host_factory(
-    const RenderProcessHostFactory* rph_factory) {
-  g_render_process_host_factory_ = rph_factory;
-}
-
 BrowserContext* SiteInstanceImpl::GetBrowserContext() const {
   return browsing_instance_->browser_context();
 }
 
 // static
 scoped_refptr<SiteInstance> SiteInstance::Create(
     BrowserContext* browser_context) {
   return SiteInstanceImpl::Create(browser_context);
 }
 
@@ skipping 152 matching lines @@
             browsing_instance_->browser_context(), site_))
       return;
 
     ChildProcessSecurityPolicyImpl* policy =
         ChildProcessSecurityPolicyImpl::GetInstance();
     policy->LockToOrigin(process_->GetID(), site_);
   }
 }
 
 }  // namespace content