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content / renderer / render_process_impl.cc [blame]
// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "content/renderer/render_process_impl.h"
#include "build/build_config.h"
#if BUILDFLAG(IS_WIN)
#include <windows.h>
#include <mlang.h>
#include <objidl.h>
#endif
#include <stddef.h>
#include <algorithm>
#include <utility>
#include "base/base_switches.h"
#include "base/command_line.h"
#include "base/compiler_specific.h"
#include "base/debug/crash_logging.h"
#include "base/feature_list.h"
#include "base/functional/bind.h"
#include "base/memory/ptr_util.h"
#include "base/synchronization/waitable_event.h"
#include "base/system/sys_info.h"
#include "base/task/task_features.h"
#include "base/task/thread_pool/initialization_util.h"
#include "base/task/thread_pool/thread_pool_instance.h"
#include "content/common/features.h"
#include "content/common/thread_pool_util.h"
#include "content/public/common/bindings_policy.h"
#include "content/public/common/content_client.h"
#include "content/public/common/content_features.h"
#include "content/public/common/content_switches.h"
#include "content/public/renderer/content_renderer_client.h"
#include "services/network/public/cpp/features.h"
#include "third_party/blink/public/common/features.h"
#include "third_party/blink/public/platform/web_runtime_features.h"
#include "third_party/blink/public/web/blink.h"
#include "third_party/blink/public/web/web_frame.h"
#include "v8/include/v8-initialization.h"
#if BUILDFLAG(IS_WIN)
#include "base/win/win_util.h"
#endif
namespace {
void SetV8FlagIfOverridden(const base::Feature& feature,
const char* enabling_flag,
const char* disabling_flag) {
auto overridden_state = base::FeatureList::GetStateIfOverridden(feature);
if (!overridden_state.has_value()) {
return;
}
if (overridden_state.value()) {
v8::V8::SetFlagsFromString(enabling_flag, strlen(enabling_flag));
} else {
v8::V8::SetFlagsFromString(disabling_flag, strlen(disabling_flag));
}
}
void SetV8FlagIfHasSwitch(const char* switch_name, const char* v8_flag) {
if (base::CommandLine::ForCurrentProcess()->HasSwitch(switch_name)) {
v8::V8::SetFlagsFromString(v8_flag, strlen(v8_flag));
}
}
std::unique_ptr<base::ThreadPoolInstance::InitParams>
GetThreadPoolInitParams() {
constexpr size_t kMaxNumThreadsInForegroundPoolLowerBound = 3;
size_t desired_num_threads =
std::max(kMaxNumThreadsInForegroundPoolLowerBound,
content::GetMinForegroundThreadsInRendererThreadPool());
if (base::FeatureList::IsEnabled(base::kThreadPoolCap2)) {
// Cap the threadpool to an initial fixed size.
// Note: The size can still grow beyond the value set here
// when tasks are blocked for a certain period of time.
const int max_allowed_workers_per_pool =
base::kThreadPoolCapRestrictedCount.Get();
desired_num_threads = std::min(
desired_num_threads, static_cast<size_t>(max_allowed_workers_per_pool));
}
return std::make_unique<base::ThreadPoolInstance::InitParams>(
desired_num_threads);
}
#if BUILDFLAG(DCHECK_IS_CONFIGURABLE)
void V8DcheckCallbackHandler(const char* file, int line, const char* message) {
// Only file/line are used from base::Location::Current() inside DCHECKs right
// now so this should correctly pretend to be the original v8 point of
// failure.
::logging::CheckError::DCheck(message,
base::Location::Current("", file, line));
}
#endif // BUILDFLAG(DCHECK_IS_CONFIGURABLE)
} // namespace
namespace content {
RenderProcessImpl::RenderProcessImpl()
: RenderProcess(GetThreadPoolInitParams()) {
#if BUILDFLAG(DCHECK_IS_CONFIGURABLE)
// Some official builds ship with DCHECKs compiled in. Failing DCHECKs then
// are either fatal or simply log the error, based on a feature flag.
// Make sure V8 follows suit by setting a Dcheck handler that forwards to
// the Chrome base logging implementation.
v8::V8::SetDcheckErrorHandler(&V8DcheckCallbackHandler);
if (!base::FeatureList::IsEnabled(base::kDCheckIsFatalFeature)) {
// These V8 flags default on in this build configuration. This triggers
// additional verification and code generation, which both slows down V8,
// and can lead to fatal CHECKs. Turn these flags down to get something
// closer to V8s normal performance and behavior.
constexpr char kDisabledFlags[] =
"--noturbo_verify "
"--noturbo_verify_allocation "
"--nodebug_code";
v8::V8::SetFlagsFromString(kDisabledFlags, sizeof(kDisabledFlags));
}
#endif // BUILDFLAG(DCHECK_IS_CONFIGURABLE)
if (base::SysInfo::IsLowEndDevice()) {
std::string optimize_flag("--optimize-for-size");
v8::V8::SetFlagsFromString(optimize_flag.c_str(), optimize_flag.size());
}
/////////////////////////////////////////////////////////////////////////////
// V8 flags are typically set in gin/v8_initializer.cc. Only those flags
// should be set here that cannot be set in gin/v8_initializer.cc because
// e.g. the flag can be set in chrome://flags.
/////////////////////////////////////////////////////////////////////////////
SetV8FlagIfHasSwitch(switches::kDisableJavaScriptHarmonyShipping,
"--noharmony-shipping");
SetV8FlagIfHasSwitch(switches::kJavaScriptHarmony, "--harmony");
SetV8FlagIfHasSwitch(switches::kEnableExperimentalWebAssemblyFeatures,
"--wasm-staging");
SetV8FlagIfOverridden(features::kV8VmFuture, "--future", "--no-future");
SetV8FlagIfOverridden(features::kWebAssemblyBaseline, "--liftoff",
"--no-liftoff");
// V8's WASM stack switching support is sufficient to enable JavaScript
// Promise Integration.
SetV8FlagIfOverridden(features::kEnableExperimentalWebAssemblyJSPI,
"--experimental-wasm-jspi",
"--no-experimental-wasm-jspi");
SetV8FlagIfOverridden(features::kWebAssemblyLazyCompilation,
"--wasm-lazy-compilation",
"--no-wasm-lazy-compilation");
SetV8FlagIfOverridden(features::kWebAssemblyMemory64,
"--experimental-wasm-memory64",
"--no-experimental-wasm-memory64");
SetV8FlagIfOverridden(features::kWebAssemblyTiering, "--wasm-tier-up",
"--no-wasm-tier-up");
SetV8FlagIfOverridden(features::kWebAssemblyDynamicTiering,
"--wasm-dynamic-tiering", "--no-wasm-dynamic-tiering");
SetV8FlagIfOverridden(blink::features::kWebAssemblyJSStringBuiltins,
"--experimental-wasm-imported-strings",
"--no-experimental-wasm-imported-strings");
bool enable_shared_array_buffer_unconditionally =
base::FeatureList::IsEnabled(features::kSharedArrayBuffer);
#if !BUILDFLAG(IS_ANDROID)
// Bypass the SAB restriction for the Finch "kill switch".
enable_shared_array_buffer_unconditionally =
enable_shared_array_buffer_unconditionally ||
base::FeatureList::IsEnabled(features::kSharedArrayBufferOnDesktop);
// Bypass the SAB restriction when enabled by Enterprise Policy.
if (!enable_shared_array_buffer_unconditionally &&
base::CommandLine::ForCurrentProcess()->HasSwitch(
switches::kSharedArrayBufferUnrestrictedAccessAllowed)) {
enable_shared_array_buffer_unconditionally = true;
blink::WebRuntimeFeatures::EnableSharedArrayBufferUnrestrictedAccessAllowed(
true);
}
#endif
if (!enable_shared_array_buffer_unconditionally) {
// It is still possible to enable SharedArrayBuffer per context using the
// `SharedArrayBufferConstructorEnabledCallback`. This will be done if the
// context is cross-origin isolated or if it opts in into the reverse origin
// trial.
constexpr char kSABPerContextFlag[] =
"--enable-sharedarraybuffer-per-context";
v8::V8::SetFlagsFromString(kSABPerContextFlag, sizeof(kSABPerContextFlag));
}
if (base::FeatureList::IsEnabled(features::kWebAssemblyTrapHandler)) {
content::GetContentClient()->renderer()->SetUpWebAssemblyTrapHandler();
}
}
RenderProcessImpl::~RenderProcessImpl() {
#ifndef NDEBUG
int count = blink::WebFrame::InstanceCount();
if (count)
DLOG(ERROR) << "WebFrame LEAKED " << count << " TIMES";
#endif
GetShutDownEvent()->Signal();
}
std::unique_ptr<RenderProcess> RenderProcessImpl::Create() {
return base::WrapUnique(new RenderProcessImpl());
}
void RenderProcessImpl::AddRefProcess() {
NOTREACHED_IN_MIGRATION();
}
void RenderProcessImpl::ReleaseProcess() {
NOTREACHED_IN_MIGRATION();
}
} // namespace content