Prerender: Introduce PrerenderCancellationReason
I think a nested cancellation reason is needed, as many final status
actually cover more than one cases, and a detailed reason is expected
to be recorded in UMA and sent to devtools.
For example:
- MojoBinderPolicy covers many interfaces.
- kInactivePageRestriction covers many disallow activation reasons.
- [To be added] navigation parameters might mismatch, and we will fail
the activation, wanting to know the parameter that causes the
failure.
Currently, we are handling these reasons in the following way:
1. introduce another function to record the detailed reason.
2. when cancelling prerendering for reason X, we:
2.1 Call the function to record metrics.
2.2 Send a message to devtools
2.3 Add an exception into the place where we send messages to
devtools to ignore reason X.
3. Cancel prerendering
With PrerenderCancellationReason, we can:
1. Keep as many as metric logics inside prerender_metrics.cc, rather
than exposing many recording functions.
2. Make it simpler to send the detailed reasons to devtools without
adding many exceptions.
Bug: 1377230
Change-Id: I7114929915fee7d03c74e891498a293caec615b4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3898651
Reviewed-by: Alex Moshchuk <alexmos@chromium.org>
Reviewed-by: Hiroki Nakagawa <nhiroki@chromium.org>
Reviewed-by: Rakina Zata Amni <rakina@chromium.org>
Reviewed-by: Asami Doi <asamidoi@chromium.org>
Commit-Queue: Lingqi Chi <lingqi@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1074452}
diff --git a/content/browser/preloading/prerender/prerender_host_registry.cc b/content/browser/preloading/prerender/prerender_host_registry.cc
index bf95f96..b15906c 100644
--- a/content/browser/preloading/prerender/prerender_host_registry.cc
+++ b/content/browser/preloading/prerender/prerender_host_registry.cc
@@ -394,6 +394,13 @@
bool PrerenderHostRegistry::CancelHost(int frame_tree_node_id,
PrerenderFinalStatus final_status) {
+ return CancelHost(frame_tree_node_id,
+ PrerenderCancellationReason(final_status));
+}
+
+bool PrerenderHostRegistry::CancelHost(
+ int frame_tree_node_id,
+ const PrerenderCancellationReason& reason) {
TRACE_EVENT1("navigation", "PrerenderHostRegistry::CancelHost",
"frame_tree_node_id", frame_tree_node_id);
@@ -406,6 +413,9 @@
if (iter == prerender_host_by_frame_tree_node_id_.end())
return false;
+ reason.ReportMetrics(iter->second->trigger_type(),
+ iter->second->embedder_histogram_suffix());
+
// Remove the prerender host from the host map so that it's not used for
// activation during asynchronous deletion.
@@ -413,7 +423,8 @@
prerender_host_by_frame_tree_node_id_.erase(iter);
// Asynchronously delete the prerender host.
- ScheduleToDeleteAbandonedHost(std::move(prerender_host), final_status);
+ ScheduleToDeleteAbandonedHost(std::move(prerender_host),
+ reason.final_status());
// Start another prerender if the running prerender is cancelled.
if (running_prerender_host_id_ == frame_tree_node_id) {
