a18a674bb8
The new platform can be used in combination with --single-threaded. It disables background threads and thus avoids waiting on mutexes and condition variables completely, which is useful for V8 embedders that fork the V8 process after initialization. As a bonus the new platform allows use to test --single-threaded and has already uncovered an existing bug in parallel pointer updating code. Change-Id: I3446fa027d2a077641cdaac0cd08062a1acae176 Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2416501 Commit-Queue: Ulan Degenbaev <ulan@chromium.org> Reviewed-by: Michael Lippautz <mlippautz@chromium.org> Cr-Commit-Position: refs/heads/master@{#71187}
118 lines
4.4 KiB
C++
118 lines
4.4 KiB
C++
// Copyright 2014 the V8 project authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style license that can be
|
|
// found in the LICENSE file.
|
|
|
|
#ifndef V8_LIBPLATFORM_LIBPLATFORM_H_
|
|
#define V8_LIBPLATFORM_LIBPLATFORM_H_
|
|
|
|
#include <memory>
|
|
|
|
#include "libplatform/libplatform-export.h"
|
|
#include "libplatform/v8-tracing.h"
|
|
#include "v8-platform.h" // NOLINT(build/include_directory)
|
|
#include "v8config.h" // NOLINT(build/include_directory)
|
|
|
|
namespace v8 {
|
|
namespace platform {
|
|
|
|
enum class IdleTaskSupport { kDisabled, kEnabled };
|
|
enum class InProcessStackDumping { kDisabled, kEnabled };
|
|
|
|
enum class MessageLoopBehavior : bool {
|
|
kDoNotWait = false,
|
|
kWaitForWork = true
|
|
};
|
|
|
|
/**
|
|
* Returns a new instance of the default v8::Platform implementation.
|
|
*
|
|
* The caller will take ownership of the returned pointer. |thread_pool_size|
|
|
* is the number of worker threads to allocate for background jobs. If a value
|
|
* of zero is passed, a suitable default based on the current number of
|
|
* processors online will be chosen.
|
|
* If |idle_task_support| is enabled then the platform will accept idle
|
|
* tasks (IdleTasksEnabled will return true) and will rely on the embedder
|
|
* calling v8::platform::RunIdleTasks to process the idle tasks.
|
|
* If |tracing_controller| is nullptr, the default platform will create a
|
|
* v8::platform::TracingController instance and use it.
|
|
*/
|
|
V8_PLATFORM_EXPORT std::unique_ptr<v8::Platform> NewDefaultPlatform(
|
|
int thread_pool_size = 0,
|
|
IdleTaskSupport idle_task_support = IdleTaskSupport::kDisabled,
|
|
InProcessStackDumping in_process_stack_dumping =
|
|
InProcessStackDumping::kDisabled,
|
|
std::unique_ptr<v8::TracingController> tracing_controller = {});
|
|
|
|
/**
|
|
* The same as NewDefaultPlatform but disables the worker thread pool.
|
|
* It must be used with the --single-threaded V8 flag.
|
|
*/
|
|
V8_PLATFORM_EXPORT std::unique_ptr<v8::Platform>
|
|
NewSingleThreadedDefaultPlatform(
|
|
IdleTaskSupport idle_task_support = IdleTaskSupport::kDisabled,
|
|
InProcessStackDumping in_process_stack_dumping =
|
|
InProcessStackDumping::kDisabled,
|
|
std::unique_ptr<v8::TracingController> tracing_controller = {});
|
|
|
|
/**
|
|
* Returns a new instance of the default v8::JobHandle implementation.
|
|
*
|
|
* The job will be executed by spawning up to |num_worker_threads| many worker
|
|
* threads on the provided |platform| with the given |priority|.
|
|
*/
|
|
V8_PLATFORM_EXPORT std::unique_ptr<v8::JobHandle> NewDefaultJobHandle(
|
|
v8::Platform* platform, v8::TaskPriority priority,
|
|
std::unique_ptr<v8::JobTask> job_task, size_t num_worker_threads);
|
|
|
|
/**
|
|
* Pumps the message loop for the given isolate.
|
|
*
|
|
* The caller has to make sure that this is called from the right thread.
|
|
* Returns true if a task was executed, and false otherwise. If the call to
|
|
* PumpMessageLoop is nested within another call to PumpMessageLoop, only
|
|
* nestable tasks may run. Otherwise, any task may run. Unless requested through
|
|
* the |behavior| parameter, this call does not block if no task is pending. The
|
|
* |platform| has to be created using |NewDefaultPlatform|.
|
|
*/
|
|
V8_PLATFORM_EXPORT bool PumpMessageLoop(
|
|
v8::Platform* platform, v8::Isolate* isolate,
|
|
MessageLoopBehavior behavior = MessageLoopBehavior::kDoNotWait);
|
|
|
|
/**
|
|
* Runs pending idle tasks for at most |idle_time_in_seconds| seconds.
|
|
*
|
|
* The caller has to make sure that this is called from the right thread.
|
|
* This call does not block if no task is pending. The |platform| has to be
|
|
* created using |NewDefaultPlatform|.
|
|
*/
|
|
V8_PLATFORM_EXPORT void RunIdleTasks(v8::Platform* platform,
|
|
v8::Isolate* isolate,
|
|
double idle_time_in_seconds);
|
|
|
|
/**
|
|
* Attempts to set the tracing controller for the given platform.
|
|
*
|
|
* The |platform| has to be created using |NewDefaultPlatform|.
|
|
*
|
|
*/
|
|
V8_DEPRECATE_SOON("Access the DefaultPlatform directly")
|
|
V8_PLATFORM_EXPORT void SetTracingController(
|
|
v8::Platform* platform,
|
|
v8::platform::tracing::TracingController* tracing_controller);
|
|
|
|
/**
|
|
* Notifies the given platform about the Isolate getting deleted soon. Has to be
|
|
* called for all Isolates which are deleted - unless we're shutting down the
|
|
* platform.
|
|
*
|
|
* The |platform| has to be created using |NewDefaultPlatform|.
|
|
*
|
|
*/
|
|
V8_PLATFORM_EXPORT void NotifyIsolateShutdown(v8::Platform* platform,
|
|
Isolate* isolate);
|
|
|
|
} // namespace platform
|
|
} // namespace v8
|
|
|
|
#endif // V8_LIBPLATFORM_LIBPLATFORM_H_
|