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Diffstat (limited to 'chromium/base/profiler/suspendable_thread_delegate.h')
-rw-r--r-- | chromium/base/profiler/suspendable_thread_delegate.h | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/chromium/base/profiler/suspendable_thread_delegate.h b/chromium/base/profiler/suspendable_thread_delegate.h new file mode 100644 index 00000000000..b5dfcd7bf12 --- /dev/null +++ b/chromium/base/profiler/suspendable_thread_delegate.h @@ -0,0 +1,59 @@ +// Copyright 2019 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. + +#ifndef BASE_PROFILER_SUSPENDABLE_THREAD_DELEGATE_H_ +#define BASE_PROFILER_SUSPENDABLE_THREAD_DELEGATE_H_ + +#include <vector> + +#include "base/base_export.h" +#include "base/profiler/register_context.h" +#include "base/profiler/thread_delegate.h" + +namespace base { + +// Platform-specific thread and stack manipulation delegate, for use by the +// platform-independent stack copying/walking implementation in +// StackSamplerImpl for suspension-based stack copying. +// +// IMPORTANT NOTE: Most methods in this interface are invoked while the target +// thread is suspended so must not do any allocation from the heap, including +// indirectly via use of DCHECK/CHECK or other logging statements. Otherwise the +// implementation can deadlock on heap locks acquired by the target thread +// before it was suspended. These functions are commented with "NO HEAP +// ALLOCATIONS". +class BASE_EXPORT SuspendableThreadDelegate : public ThreadDelegate { + public: + // Implementations of this interface should suspend the thread for the + // object's lifetime. NO HEAP ALLOCATIONS between the time the thread is + // suspended and resumed. + class BASE_EXPORT ScopedSuspendThread { + public: + ScopedSuspendThread() = default; + virtual ~ScopedSuspendThread() = default; + + ScopedSuspendThread(const ScopedSuspendThread&) = delete; + ScopedSuspendThread& operator=(const ScopedSuspendThread&) = delete; + + virtual bool WasSuccessful() const = 0; + }; + + SuspendableThreadDelegate() = default; + + // Creates an object that holds the thread suspended for its lifetime. + virtual std::unique_ptr<ScopedSuspendThread> CreateScopedSuspendThread() = 0; + + // Gets the register context for the thread. + // NO HEAP ALLOCATIONS. + virtual bool GetThreadContext(RegisterContext* thread_context) = 0; + + // Returns true if the thread's stack can be copied, where the bottom address + // of the thread is at |stack_pointer|. + // NO HEAP ALLOCATIONS. + virtual bool CanCopyStack(uintptr_t stack_pointer) = 0; +}; + +} // namespace base + +#endif // BASE_PROFILER_SUSPENDABLE_THREAD_DELEGATE_H_ |