gecko/tools/profiler/UnwinderThread2.h
Benoit Girard 83196070ce Bug 856331 - Make breakpad unwinding runtime switchable. r=jseward
--HG--
extra : rebase_source : 1094beb17115a0d0e4d27eeb848c3932dfe0b2b0
2013-04-01 15:45:03 -04:00

68 lines
2.9 KiB
C

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef MOZ_UNWINDER_THREAD_2_H
#define MOZ_UNWINDER_THREAD_2_H
#include "GeckoProfilerImpl.h"
#include "ProfileEntry.h"
/* Top level exports of UnwinderThread.cpp. */
// Abstract type. A buffer which is used to transfer information between
// the sampled thread(s) and the unwinder thread(s).
typedef
struct _UnwinderThreadBuffer
UnwinderThreadBuffer;
// RUNS IN SIGHANDLER CONTEXT
// Called in the sampled thread (signal) context. Adds a ProfileEntry
// into an UnwinderThreadBuffer that the thread has previously obtained
// by a call to utb__acquire_empty_buffer.
void utb__addEntry(/*MOD*/UnwinderThreadBuffer* utb,
ProfileEntry ent);
// Create the unwinder thread. At the moment there can be only one.
void uwt__init();
// Request the unwinder thread to exit, and wait until it has done so.
// This must be called before stopping the profiler because we hold a
// reference to the profile which is owned by the profiler.
void uwt__stop();
// Release the unwinder resources. This must be called after profiling
// has stop. At this point we know the profiler doesn't hold any buffer
// and can safely release any resources.
void uwt__deinit();
// Registers a sampler thread for profiling. Threads must be registered
// before they are allowed to call utb__acquire_empty_buffer or
// utb__release_full_buffer.
void uwt__register_thread_for_profiling(void* stackTop);
// RUNS IN SIGHANDLER CONTEXT
// Called in the sampled thread (signal) context. Get an empty buffer
// into which ProfileEntries can be put. It may return NULL if no
// empty buffers can be found, which will be the case if the unwinder
// thread(s) have fallen behind for some reason. In this case the
// sampled thread must simply give up and return from the signal handler
// immediately, else it risks deadlock.
UnwinderThreadBuffer* uwt__acquire_empty_buffer();
// RUNS IN SIGHANDLER CONTEXT
// Called in the sampled thread (signal) context. Release a buffer
// that the sampled thread has acquired, handing the contents to
// the unwinder thread, and, if necessary, passing sufficient
// information (stack top chunk, + registers) to also do a native
// unwind. If 'ucV' is NULL, no native unwind is done. If non-NULL,
// it is assumed to point to a ucontext_t* that holds the initial
// register state for the unwind. The results of all of this are
// dumped into |aProfile| (by the unwinder thread, not the calling thread).
void uwt__release_full_buffer(ThreadProfile* aProfile,
UnwinderThreadBuffer* utb,
void* /* ucontext_t*, really */ ucV);
#endif /* ndef MOZ_UNWINDER_THREAD_2_H */