481 lines
15 KiB
C++
481 lines
15 KiB
C++
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// Copyright 2013 the V8 project authors. All rights reserved.
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// Redistribution and use in source and binary forms, with or without
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// modification, are permitted provided that the following conditions are
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// met:
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//
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// * Redistributions of source code must retain the above copyright
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// notice, this list of conditions and the following disclaimer.
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// * Redistributions in binary form must reproduce the above
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// copyright notice, this list of conditions and the following
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// disclaimer in the documentation and/or other materials provided
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// with the distribution.
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// * Neither the name of Google Inc. nor the names of its
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// contributors may be used to endorse or promote products derived
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// from this software without specific prior written permission.
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//
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// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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#if defined(__linux__) || defined(__FreeBSD__) || defined(__OpenBSD__) \
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|| defined(__NetBSD__) || defined(__sun)
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#include <errno.h>
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#include <pthread.h>
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#include <signal.h>
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#include <sys/time.h>
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#include <sys/syscall.h>
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#include <ucontext.h>
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#include <unistd.h>
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#endif
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// GLibc on ARM defines mcontext_t has a typedef for 'struct sigcontext'.
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// Old versions of the C library <signal.h> didn't define the type.
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#if defined(__ANDROID__) && !defined(__BIONIC_HAVE_UCONTEXT_T) && \
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defined(__arm__) && !defined(__BIONIC_HAVE_STRUCT_SIGCONTEXT)
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#include <asm/sigcontext.h>
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#endif
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#include "v8.h"
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#include "log.h"
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#include "platform.h"
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#include "simulator.h"
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#include "v8threads.h"
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namespace v8 {
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namespace internal {
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#if defined(__linux__) || defined(__FreeBSD__) || defined(__OpenBSD__) \
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|| defined(__NetBSD__) || defined(__sun)
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#if defined(__ANDROID__) && !defined(__BIONIC_HAVE_UCONTEXT_T)
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// Not all versions of Android's C library provide ucontext_t.
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// Detect this and provide custom but compatible definitions. Note that these
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// follow the GLibc naming convention to access register values from
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// mcontext_t.
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//
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// See http://code.google.com/p/android/issues/detail?id=34784
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#if defined(__arm__)
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typedef struct sigcontext mcontext_t;
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typedef struct ucontext {
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uint32_t uc_flags;
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struct ucontext* uc_link;
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stack_t uc_stack;
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mcontext_t uc_mcontext;
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// Other fields are not used by V8, don't define them here.
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} ucontext_t;
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#elif defined(__mips__)
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// MIPS version of sigcontext, for Android bionic.
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typedef struct {
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uint32_t regmask;
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uint32_t status;
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uint64_t pc;
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uint64_t gregs[32];
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uint64_t fpregs[32];
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uint32_t acx;
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uint32_t fpc_csr;
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uint32_t fpc_eir;
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uint32_t used_math;
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uint32_t dsp;
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uint64_t mdhi;
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uint64_t mdlo;
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uint32_t hi1;
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uint32_t lo1;
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uint32_t hi2;
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uint32_t lo2;
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uint32_t hi3;
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uint32_t lo3;
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} mcontext_t;
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typedef struct ucontext {
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uint32_t uc_flags;
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struct ucontext* uc_link;
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stack_t uc_stack;
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mcontext_t uc_mcontext;
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// Other fields are not used by V8, don't define them here.
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} ucontext_t;
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#elif defined(__i386__)
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// x86 version for Android.
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typedef struct {
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uint32_t gregs[19];
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void* fpregs;
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uint32_t oldmask;
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uint32_t cr2;
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} mcontext_t;
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typedef uint32_t kernel_sigset_t[2]; // x86 kernel uses 64-bit signal masks
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typedef struct ucontext {
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uint32_t uc_flags;
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struct ucontext* uc_link;
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stack_t uc_stack;
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mcontext_t uc_mcontext;
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// Other fields are not used by V8, don't define them here.
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} ucontext_t;
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enum { REG_EBP = 6, REG_ESP = 7, REG_EIP = 14 };
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#endif
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#endif // __ANDROID__ && !defined(__BIONIC_HAVE_UCONTEXT_T)
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static pthread_t GetThreadID() {
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#if defined(__ANDROID__)
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// Android's C library provides gettid(2).
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return gettid();
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#elif defined(__linux__)
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// Glibc doesn't provide a wrapper for gettid(2).
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return syscall(SYS_gettid);
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#elif defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__NetBSD__) \
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|| defined(__sun)
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return pthread_self();
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#endif
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}
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class Sampler::PlatformData : public Malloced {
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public:
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PlatformData()
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: vm_tid_(GetThreadID()),
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profiled_thread_id_(ThreadId::Current()) {}
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pthread_t vm_tid() const { return vm_tid_; }
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ThreadId profiled_thread_id() { return profiled_thread_id_; }
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private:
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pthread_t vm_tid_;
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ThreadId profiled_thread_id_;
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};
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static void ProfilerSignalHandler(int signal, siginfo_t* info, void* context) {
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#if defined(__native_client__)
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// As Native Client does not support signal handling, profiling
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// is disabled.
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return;
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#else
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USE(info);
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if (signal != SIGPROF) return;
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Isolate* isolate = Isolate::UncheckedCurrent();
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if (isolate == NULL || !isolate->IsInitialized() || !isolate->IsInUse()) {
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// We require a fully initialized and entered isolate.
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return;
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}
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if (v8::Locker::IsActive() &&
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!isolate->thread_manager()->IsLockedByCurrentThread()) {
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return;
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}
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Sampler* sampler = isolate->logger()->sampler();
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if (sampler == NULL || !sampler->IsActive()) return;
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#if defined(USE_SIMULATOR)
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#if V8_TARGET_ARCH_ARM || V8_TARGET_ARCH_MIPS
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ThreadId thread_id = sampler->platform_data()->profiled_thread_id();
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Isolate::PerIsolateThreadData* per_thread_data = isolate->
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FindPerThreadDataForThread(thread_id);
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if (!per_thread_data) return;
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Simulator* sim = per_thread_data->simulator();
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// Check if there is active simulator before allocating TickSample.
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if (!sim) return;
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#endif
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#endif // USE_SIMULATOR
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TickSample sample_obj;
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TickSample* sample = isolate->cpu_profiler()->TickSampleEvent();
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if (sample == NULL) sample = &sample_obj;
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#if defined(USE_SIMULATOR)
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#if V8_TARGET_ARCH_ARM
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sample->pc = reinterpret_cast<Address>(sim->get_register(Simulator::pc));
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sample->sp = reinterpret_cast<Address>(sim->get_register(Simulator::sp));
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sample->fp = reinterpret_cast<Address>(sim->get_register(Simulator::r11));
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#elif V8_TARGET_ARCH_MIPS
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sample->pc = reinterpret_cast<Address>(sim->get_register(Simulator::pc));
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sample->sp = reinterpret_cast<Address>(sim->get_register(Simulator::sp));
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sample->fp = reinterpret_cast<Address>(sim->get_register(Simulator::fp));
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#endif // V8_TARGET_ARCH_*
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#else
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// Extracting the sample from the context is extremely machine dependent.
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ucontext_t* ucontext = reinterpret_cast<ucontext_t*>(context);
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mcontext_t& mcontext = ucontext->uc_mcontext;
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sample->state = isolate->current_vm_state();
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#if defined(__linux__)
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#if V8_HOST_ARCH_IA32
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sample->pc = reinterpret_cast<Address>(mcontext.gregs[REG_EIP]);
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sample->sp = reinterpret_cast<Address>(mcontext.gregs[REG_ESP]);
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sample->fp = reinterpret_cast<Address>(mcontext.gregs[REG_EBP]);
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#elif V8_HOST_ARCH_X64
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sample->pc = reinterpret_cast<Address>(mcontext.gregs[REG_RIP]);
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sample->sp = reinterpret_cast<Address>(mcontext.gregs[REG_RSP]);
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sample->fp = reinterpret_cast<Address>(mcontext.gregs[REG_RBP]);
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#elif V8_HOST_ARCH_ARM
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#if defined(__GLIBC__) && !defined(__UCLIBC__) && \
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(__GLIBC__ < 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ <= 3))
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// Old GLibc ARM versions used a gregs[] array to access the register
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// values from mcontext_t.
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sample->pc = reinterpret_cast<Address>(mcontext.gregs[R15]);
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sample->sp = reinterpret_cast<Address>(mcontext.gregs[R13]);
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sample->fp = reinterpret_cast<Address>(mcontext.gregs[R11]);
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#else
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sample->pc = reinterpret_cast<Address>(mcontext.arm_pc);
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sample->sp = reinterpret_cast<Address>(mcontext.arm_sp);
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sample->fp = reinterpret_cast<Address>(mcontext.arm_fp);
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#endif // defined(__GLIBC__) && !defined(__UCLIBC__) &&
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// (__GLIBC__ < 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ <= 3))
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#elif V8_HOST_ARCH_MIPS
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sample->pc = reinterpret_cast<Address>(mcontext.pc);
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sample->sp = reinterpret_cast<Address>(mcontext.gregs[29]);
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sample->fp = reinterpret_cast<Address>(mcontext.gregs[30]);
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#endif // V8_HOST_ARCH_*
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#elif defined(__FreeBSD__)
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#if V8_HOST_ARCH_IA32
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sample->pc = reinterpret_cast<Address>(mcontext.mc_eip);
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sample->sp = reinterpret_cast<Address>(mcontext.mc_esp);
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sample->fp = reinterpret_cast<Address>(mcontext.mc_ebp);
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#elif V8_HOST_ARCH_X64
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sample->pc = reinterpret_cast<Address>(mcontext.mc_rip);
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sample->sp = reinterpret_cast<Address>(mcontext.mc_rsp);
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sample->fp = reinterpret_cast<Address>(mcontext.mc_rbp);
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#elif V8_HOST_ARCH_ARM
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sample->pc = reinterpret_cast<Address>(mcontext.mc_r15);
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sample->sp = reinterpret_cast<Address>(mcontext.mc_r13);
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sample->fp = reinterpret_cast<Address>(mcontext.mc_r11);
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#endif // V8_HOST_ARCH_*
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#elif defined(__NetBSD__)
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#if V8_HOST_ARCH_IA32
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sample->pc = reinterpret_cast<Address>(mcontext.__gregs[_REG_EIP]);
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sample->sp = reinterpret_cast<Address>(mcontext.__gregs[_REG_ESP]);
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sample->fp = reinterpret_cast<Address>(mcontext.__gregs[_REG_EBP]);
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#elif V8_HOST_ARCH_X64
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sample->pc = reinterpret_cast<Address>(mcontext.__gregs[_REG_RIP]);
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sample->sp = reinterpret_cast<Address>(mcontext.__gregs[_REG_RSP]);
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sample->fp = reinterpret_cast<Address>(mcontext.__gregs[_REG_RBP]);
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#endif // V8_HOST_ARCH_*
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#elif defined(__OpenBSD__)
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USE(mcontext);
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#if V8_HOST_ARCH_IA32
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sample->pc = reinterpret_cast<Address>(ucontext->sc_eip);
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sample->sp = reinterpret_cast<Address>(ucontext->sc_esp);
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sample->fp = reinterpret_cast<Address>(ucontext->sc_ebp);
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#elif V8_HOST_ARCH_X64
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sample->pc = reinterpret_cast<Address>(ucontext->sc_rip);
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sample->sp = reinterpret_cast<Address>(ucontext->sc_rsp);
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sample->fp = reinterpret_cast<Address>(ucontext->sc_rbp);
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#endif // V8_HOST_ARCH_*
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#elif defined(__sun)
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sample->pc = reinterpret_cast<Address>(mcontext.gregs[REG_PC]);
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sample->sp = reinterpret_cast<Address>(mcontext.gregs[REG_SP]);
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sample->fp = reinterpret_cast<Address>(mcontext.gregs[REG_FP]);
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#endif // __sun
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#endif // USE_SIMULATOR
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sampler->SampleStack(sample);
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sampler->Tick(sample);
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#endif // __native_client__
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}
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class SignalSender : public Thread {
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public:
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static const int kSignalSenderStackSize = 64 * KB;
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explicit SignalSender(int interval)
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: Thread(Thread::Options("SignalSender", kSignalSenderStackSize)),
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vm_tgid_(getpid()),
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interval_(interval) {}
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static void SetUp() { if (!mutex_) mutex_ = OS::CreateMutex(); }
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static void TearDown() { delete mutex_; }
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static void InstallSignalHandler() {
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struct sigaction sa;
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sa.sa_sigaction = ProfilerSignalHandler;
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sigemptyset(&sa.sa_mask);
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sa.sa_flags = SA_RESTART | SA_SIGINFO;
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signal_handler_installed_ =
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(sigaction(SIGPROF, &sa, &old_signal_handler_) == 0);
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}
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static void RestoreSignalHandler() {
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if (signal_handler_installed_) {
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sigaction(SIGPROF, &old_signal_handler_, 0);
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signal_handler_installed_ = false;
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}
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}
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static void AddActiveSampler(Sampler* sampler) {
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ScopedLock lock(mutex_);
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SamplerRegistry::AddActiveSampler(sampler);
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if (instance_ == NULL) {
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// Start a thread that will send SIGPROF signal to VM threads,
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// when CPU profiling will be enabled.
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instance_ = new SignalSender(sampler->interval());
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instance_->StartSynchronously();
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} else {
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ASSERT(instance_->interval_ == sampler->interval());
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}
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}
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static void RemoveActiveSampler(Sampler* sampler) {
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ScopedLock lock(mutex_);
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SamplerRegistry::RemoveActiveSampler(sampler);
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if (SamplerRegistry::GetState() == SamplerRegistry::HAS_NO_SAMPLERS) {
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instance_->Join();
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delete instance_;
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instance_ = NULL;
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RestoreSignalHandler();
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}
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}
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// Implement Thread::Run().
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virtual void Run() {
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SamplerRegistry::State state;
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while ((state = SamplerRegistry::GetState()) !=
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SamplerRegistry::HAS_NO_SAMPLERS) {
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// When CPU profiling is enabled both JavaScript and C++ code is
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// profiled. We must not suspend.
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if (state == SamplerRegistry::HAS_CPU_PROFILING_SAMPLERS) {
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if (!signal_handler_installed_) InstallSignalHandler();
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SamplerRegistry::IterateActiveSamplers(&DoCpuProfile, this);
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} else {
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if (signal_handler_installed_) RestoreSignalHandler();
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}
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Sleep(); // TODO(svenpanne) Figure out if OS:Sleep(interval_) is enough.
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}
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}
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static void DoCpuProfile(Sampler* sampler, void* raw_sender) {
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if (!sampler->IsProfiling()) return;
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SignalSender* sender = reinterpret_cast<SignalSender*>(raw_sender);
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sender->SendProfilingSignal(sampler->platform_data()->vm_tid());
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}
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void SendProfilingSignal(int tid) {
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if (!signal_handler_installed_) return;
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// Glibc doesn't provide a wrapper for tgkill(2).
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#if defined(ANDROID)
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syscall(__NR_tgkill, vm_tgid_, tid, SIGPROF);
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#elif defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__NetBSD__) \
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|| defined(__sun)
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pthread_kill(tid, SIGPROF);
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#else
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int result = syscall(SYS_tgkill, vm_tgid_, tid, SIGPROF);
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USE(result);
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ASSERT(result == 0);
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#endif
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}
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void Sleep() {
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// Convert ms to us and subtract 100 us to compensate delays
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// occuring during signal delivery.
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useconds_t interval = interval_ * 1000 - 100;
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#if defined(ANDROID)
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usleep(interval);
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#else
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int result = usleep(interval);
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#ifdef DEBUG
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if (result != 0 && errno != EINTR) {
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fprintf(stderr,
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"SignalSender usleep error; interval = %u, errno = %d\n",
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interval,
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|
errno);
|
||
|
ASSERT(result == 0 || errno == EINTR);
|
||
|
}
|
||
|
#endif // DEBUG
|
||
|
USE(result);
|
||
|
#endif // ANDROID
|
||
|
}
|
||
|
|
||
|
const int vm_tgid_;
|
||
|
const int interval_;
|
||
|
|
||
|
// Protects the process wide state below.
|
||
|
static Mutex* mutex_;
|
||
|
static SignalSender* instance_;
|
||
|
static bool signal_handler_installed_;
|
||
|
static struct sigaction old_signal_handler_;
|
||
|
|
||
|
private:
|
||
|
DISALLOW_COPY_AND_ASSIGN(SignalSender);
|
||
|
};
|
||
|
|
||
|
|
||
|
Mutex* SignalSender::mutex_ = NULL;
|
||
|
SignalSender* SignalSender::instance_ = NULL;
|
||
|
struct sigaction SignalSender::old_signal_handler_;
|
||
|
bool SignalSender::signal_handler_installed_ = false;
|
||
|
|
||
|
|
||
|
void Sampler::SetUp() {
|
||
|
SignalSender::SetUp();
|
||
|
}
|
||
|
|
||
|
|
||
|
void Sampler::TearDown() {
|
||
|
SignalSender::TearDown();
|
||
|
}
|
||
|
|
||
|
|
||
|
Sampler::Sampler(Isolate* isolate, int interval)
|
||
|
: isolate_(isolate),
|
||
|
interval_(interval),
|
||
|
profiling_(false),
|
||
|
active_(false),
|
||
|
samples_taken_(0) {
|
||
|
data_ = new PlatformData;
|
||
|
}
|
||
|
|
||
|
|
||
|
Sampler::~Sampler() {
|
||
|
ASSERT(!IsActive());
|
||
|
delete data_;
|
||
|
}
|
||
|
|
||
|
void Sampler::Start() {
|
||
|
ASSERT(!IsActive());
|
||
|
SetActive(true);
|
||
|
SignalSender::AddActiveSampler(this);
|
||
|
}
|
||
|
|
||
|
|
||
|
void Sampler::Stop() {
|
||
|
ASSERT(IsActive());
|
||
|
SignalSender::RemoveActiveSampler(this);
|
||
|
SetActive(false);
|
||
|
}
|
||
|
|
||
|
#else
|
||
|
|
||
|
void Sampler::SetUp() {
|
||
|
}
|
||
|
|
||
|
|
||
|
void Sampler::TearDown() {
|
||
|
}
|
||
|
|
||
|
#endif // __linux__ || _*BSD__ || __sun
|
||
|
|
||
|
void Sampler::SampleStack(TickSample* sample) {
|
||
|
StackTracer::Trace(isolate_, sample);
|
||
|
if (++samples_taken_ < 0) samples_taken_ = 0;
|
||
|
}
|
||
|
|
||
|
} } // namespace v8::internal
|