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/*
* Copyright (C) 2019 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "perfetto/tracing/internal/tracing_tls.h"
#include "perfetto/tracing/tracing.h"
#include "perfetto/tracing/tracing_backend.h"
// This translation unit contains the definitions for the destructor of pure
// virtual interfaces for the src/public:public target. The alternative would be
// introducing a one-liner .cc file for each pure virtual interface, which is
// overkill. This is for compliance with -Wweak-vtables.
namespace perfetto {
namespace internal {
TracingTLS::~TracingTLS() {
// Avoid entering trace points while the thread is being torn down.
// This is the problem: when a thread exits, the at-thread-exit destroys the
// TracingTLS. As part of that the various TraceWriter for the active data
// sources are destroyd. A TraceWriter dtor will issue a PostTask on the IPC
// thread to issue a final flush and unregister its ID with the service.
// The PostTask, in chromium, might have a trace event that will try to
// re-enter the tracing system.
// We fix this by resetting the TLS key to the TracingTLS object that is
// being destroyed in the platform impl (platform_posix.cc,
// platform_windows.cc, chromium's platform.cc). We carefully rely on the fact
// that all the tracing path that will be invoked during thread exit will
// early out if |is_in_trace_point| == true and will not depend on the other
// TLS state that has been destroyed.
is_in_trace_point = true;
}
} // namespace internal
TracingBackend::~TracingBackend() = default;
TracingSession::~TracingSession() = default;
} // namespace perfetto