decd0fed78
I changed the implementation of a queue between the VM and processor thread to be unbounded and lock-free, using Herb Sutter's example from DDJ article: http://www.ddj.com/high-performance-computing/210604448 This had brought back profiling overhead to a minimum for the page from Chromium's issue 16184. BUG=714 Review URL: http://codereview.chromium.org/2091019 git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4706 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
666 lines
18 KiB
C++
666 lines
18 KiB
C++
// Copyright 2006-2008 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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// Platform specific code for MacOS goes here. For the POSIX comaptible parts
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// the implementation is in platform-posix.cc.
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#include <unistd.h>
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#include <sys/mman.h>
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#include <mach/mach_init.h>
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#include <mach-o/dyld.h>
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#include <mach-o/getsect.h>
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#include <AvailabilityMacros.h>
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#include <pthread.h>
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#include <semaphore.h>
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#include <signal.h>
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#include <libkern/OSAtomic.h>
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#include <mach/mach.h>
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#include <mach/semaphore.h>
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#include <mach/task.h>
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#include <mach/vm_statistics.h>
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#include <sys/time.h>
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#include <sys/resource.h>
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#include <sys/types.h>
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#include <stdarg.h>
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#include <stdlib.h>
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#include <errno.h>
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#undef MAP_TYPE
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#include "v8.h"
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#include "platform.h"
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// Manually define these here as weak imports, rather than including execinfo.h.
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// This lets us launch on 10.4 which does not have these calls.
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extern "C" {
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extern int backtrace(void**, int) __attribute__((weak_import));
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extern char** backtrace_symbols(void* const*, int)
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__attribute__((weak_import));
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extern void backtrace_symbols_fd(void* const*, int, int)
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__attribute__((weak_import));
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}
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namespace v8 {
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namespace internal {
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// 0 is never a valid thread id on MacOSX since a ptread_t is
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// a pointer.
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static const pthread_t kNoThread = (pthread_t) 0;
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double ceiling(double x) {
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// Correct Mac OS X Leopard 'ceil' behavior.
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if (-1.0 < x && x < 0.0) {
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return -0.0;
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} else {
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return ceil(x);
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}
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}
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void OS::Setup() {
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// Seed the random number generator.
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// Convert the current time to a 64-bit integer first, before converting it
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// to an unsigned. Going directly will cause an overflow and the seed to be
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// set to all ones. The seed will be identical for different instances that
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// call this setup code within the same millisecond.
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uint64_t seed = static_cast<uint64_t>(TimeCurrentMillis());
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srandom(static_cast<unsigned int>(seed));
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}
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// We keep the lowest and highest addresses mapped as a quick way of
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// determining that pointers are outside the heap (used mostly in assertions
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// and verification). The estimate is conservative, ie, not all addresses in
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// 'allocated' space are actually allocated to our heap. The range is
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// [lowest, highest), inclusive on the low and and exclusive on the high end.
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static void* lowest_ever_allocated = reinterpret_cast<void*>(-1);
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static void* highest_ever_allocated = reinterpret_cast<void*>(0);
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static void UpdateAllocatedSpaceLimits(void* address, int size) {
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lowest_ever_allocated = Min(lowest_ever_allocated, address);
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highest_ever_allocated =
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Max(highest_ever_allocated,
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reinterpret_cast<void*>(reinterpret_cast<char*>(address) + size));
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}
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bool OS::IsOutsideAllocatedSpace(void* address) {
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return address < lowest_ever_allocated || address >= highest_ever_allocated;
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}
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size_t OS::AllocateAlignment() {
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return getpagesize();
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}
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// Constants used for mmap.
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// kMmapFd is used to pass vm_alloc flags to tag the region with the user
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// defined tag 255 This helps identify V8-allocated regions in memory analysis
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// tools like vmmap(1).
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static const int kMmapFd = VM_MAKE_TAG(255);
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static const off_t kMmapFdOffset = 0;
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void* OS::Allocate(const size_t requested,
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size_t* allocated,
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bool is_executable) {
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const size_t msize = RoundUp(requested, getpagesize());
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int prot = PROT_READ | PROT_WRITE | (is_executable ? PROT_EXEC : 0);
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void* mbase = mmap(NULL, msize, prot,
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MAP_PRIVATE | MAP_ANON,
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kMmapFd, kMmapFdOffset);
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if (mbase == MAP_FAILED) {
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LOG(StringEvent("OS::Allocate", "mmap failed"));
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return NULL;
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}
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*allocated = msize;
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UpdateAllocatedSpaceLimits(mbase, msize);
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return mbase;
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}
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void OS::Free(void* address, const size_t size) {
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// TODO(1240712): munmap has a return value which is ignored here.
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int result = munmap(address, size);
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USE(result);
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ASSERT(result == 0);
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}
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#ifdef ENABLE_HEAP_PROTECTION
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void OS::Protect(void* address, size_t size) {
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UNIMPLEMENTED();
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}
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void OS::Unprotect(void* address, size_t size, bool is_executable) {
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UNIMPLEMENTED();
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}
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#endif
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void OS::Sleep(int milliseconds) {
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usleep(1000 * milliseconds);
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}
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void OS::Abort() {
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// Redirect to std abort to signal abnormal program termination
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abort();
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}
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void OS::DebugBreak() {
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asm("int $3");
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}
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class PosixMemoryMappedFile : public OS::MemoryMappedFile {
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public:
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PosixMemoryMappedFile(FILE* file, void* memory, int size)
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: file_(file), memory_(memory), size_(size) { }
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virtual ~PosixMemoryMappedFile();
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virtual void* memory() { return memory_; }
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private:
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FILE* file_;
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void* memory_;
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int size_;
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};
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OS::MemoryMappedFile* OS::MemoryMappedFile::create(const char* name, int size,
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void* initial) {
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FILE* file = fopen(name, "w+");
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if (file == NULL) return NULL;
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fwrite(initial, size, 1, file);
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void* memory =
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mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, fileno(file), 0);
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return new PosixMemoryMappedFile(file, memory, size);
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}
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PosixMemoryMappedFile::~PosixMemoryMappedFile() {
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if (memory_) munmap(memory_, size_);
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fclose(file_);
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}
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void OS::LogSharedLibraryAddresses() {
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#ifdef ENABLE_LOGGING_AND_PROFILING
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unsigned int images_count = _dyld_image_count();
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for (unsigned int i = 0; i < images_count; ++i) {
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const mach_header* header = _dyld_get_image_header(i);
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if (header == NULL) continue;
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#if V8_HOST_ARCH_X64
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uint64_t size;
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char* code_ptr = getsectdatafromheader_64(
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reinterpret_cast<const mach_header_64*>(header),
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SEG_TEXT,
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SECT_TEXT,
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&size);
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#else
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unsigned int size;
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char* code_ptr = getsectdatafromheader(header, SEG_TEXT, SECT_TEXT, &size);
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#endif
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if (code_ptr == NULL) continue;
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const uintptr_t slide = _dyld_get_image_vmaddr_slide(i);
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const uintptr_t start = reinterpret_cast<uintptr_t>(code_ptr) + slide;
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LOG(SharedLibraryEvent(_dyld_get_image_name(i), start, start + size));
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}
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#endif // ENABLE_LOGGING_AND_PROFILING
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}
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uint64_t OS::CpuFeaturesImpliedByPlatform() {
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// MacOSX requires all these to install so we can assume they are present.
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// These constants are defined by the CPUid instructions.
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const uint64_t one = 1;
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return (one << SSE2) | (one << CMOV) | (one << RDTSC) | (one << CPUID);
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}
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int OS::ActivationFrameAlignment() {
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// OS X activation frames must be 16 byte-aligned; see "Mac OS X ABI
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// Function Call Guide".
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return 16;
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}
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void OS::ReleaseStore(volatile AtomicWord* ptr, AtomicWord value) {
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OSMemoryBarrier();
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*ptr = value;
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}
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const char* OS::LocalTimezone(double time) {
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if (isnan(time)) return "";
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time_t tv = static_cast<time_t>(floor(time/msPerSecond));
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struct tm* t = localtime(&tv);
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if (NULL == t) return "";
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return t->tm_zone;
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}
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double OS::LocalTimeOffset() {
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time_t tv = time(NULL);
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struct tm* t = localtime(&tv);
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// tm_gmtoff includes any daylight savings offset, so subtract it.
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return static_cast<double>(t->tm_gmtoff * msPerSecond -
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(t->tm_isdst > 0 ? 3600 * msPerSecond : 0));
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}
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int OS::StackWalk(Vector<StackFrame> frames) {
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// If weak link to execinfo lib has failed, ie because we are on 10.4, abort.
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if (backtrace == NULL)
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return 0;
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int frames_size = frames.length();
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ScopedVector<void*> addresses(frames_size);
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int frames_count = backtrace(addresses.start(), frames_size);
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char** symbols = backtrace_symbols(addresses.start(), frames_count);
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if (symbols == NULL) {
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return kStackWalkError;
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}
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for (int i = 0; i < frames_count; i++) {
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frames[i].address = addresses[i];
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// Format a text representation of the frame based on the information
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// available.
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SNPrintF(MutableCStrVector(frames[i].text,
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kStackWalkMaxTextLen),
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"%s",
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symbols[i]);
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// Make sure line termination is in place.
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frames[i].text[kStackWalkMaxTextLen - 1] = '\0';
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}
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free(symbols);
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return frames_count;
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}
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VirtualMemory::VirtualMemory(size_t size) {
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address_ = mmap(NULL, size, PROT_NONE,
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MAP_PRIVATE | MAP_ANON | MAP_NORESERVE,
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kMmapFd, kMmapFdOffset);
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size_ = size;
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}
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VirtualMemory::~VirtualMemory() {
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if (IsReserved()) {
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if (0 == munmap(address(), size())) address_ = MAP_FAILED;
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}
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}
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bool VirtualMemory::IsReserved() {
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return address_ != MAP_FAILED;
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}
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bool VirtualMemory::Commit(void* address, size_t size, bool is_executable) {
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int prot = PROT_READ | PROT_WRITE | (is_executable ? PROT_EXEC : 0);
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if (MAP_FAILED == mmap(address, size, prot,
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MAP_PRIVATE | MAP_ANON | MAP_FIXED,
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kMmapFd, kMmapFdOffset)) {
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return false;
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}
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UpdateAllocatedSpaceLimits(address, size);
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return true;
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}
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bool VirtualMemory::Uncommit(void* address, size_t size) {
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return mmap(address, size, PROT_NONE,
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MAP_PRIVATE | MAP_ANON | MAP_NORESERVE | MAP_FIXED,
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kMmapFd, kMmapFdOffset) != MAP_FAILED;
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}
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class ThreadHandle::PlatformData : public Malloced {
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public:
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explicit PlatformData(ThreadHandle::Kind kind) {
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Initialize(kind);
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}
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void Initialize(ThreadHandle::Kind kind) {
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switch (kind) {
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case ThreadHandle::SELF: thread_ = pthread_self(); break;
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case ThreadHandle::INVALID: thread_ = kNoThread; break;
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}
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}
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pthread_t thread_; // Thread handle for pthread.
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};
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ThreadHandle::ThreadHandle(Kind kind) {
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data_ = new PlatformData(kind);
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}
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void ThreadHandle::Initialize(ThreadHandle::Kind kind) {
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data_->Initialize(kind);
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}
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ThreadHandle::~ThreadHandle() {
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delete data_;
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}
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bool ThreadHandle::IsSelf() const {
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return pthread_equal(data_->thread_, pthread_self());
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}
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bool ThreadHandle::IsValid() const {
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return data_->thread_ != kNoThread;
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}
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Thread::Thread() : ThreadHandle(ThreadHandle::INVALID) {
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}
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Thread::~Thread() {
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}
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static void* ThreadEntry(void* arg) {
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Thread* thread = reinterpret_cast<Thread*>(arg);
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// This is also initialized by the first argument to pthread_create() but we
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// don't know which thread will run first (the original thread or the new
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// one) so we initialize it here too.
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thread->thread_handle_data()->thread_ = pthread_self();
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ASSERT(thread->IsValid());
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thread->Run();
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return NULL;
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}
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void Thread::Start() {
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pthread_create(&thread_handle_data()->thread_, NULL, ThreadEntry, this);
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}
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void Thread::Join() {
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pthread_join(thread_handle_data()->thread_, NULL);
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}
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Thread::LocalStorageKey Thread::CreateThreadLocalKey() {
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pthread_key_t key;
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int result = pthread_key_create(&key, NULL);
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USE(result);
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ASSERT(result == 0);
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return static_cast<LocalStorageKey>(key);
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}
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void Thread::DeleteThreadLocalKey(LocalStorageKey key) {
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pthread_key_t pthread_key = static_cast<pthread_key_t>(key);
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int result = pthread_key_delete(pthread_key);
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USE(result);
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ASSERT(result == 0);
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}
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void* Thread::GetThreadLocal(LocalStorageKey key) {
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pthread_key_t pthread_key = static_cast<pthread_key_t>(key);
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return pthread_getspecific(pthread_key);
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}
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void Thread::SetThreadLocal(LocalStorageKey key, void* value) {
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pthread_key_t pthread_key = static_cast<pthread_key_t>(key);
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pthread_setspecific(pthread_key, value);
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}
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void Thread::YieldCPU() {
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sched_yield();
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}
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class MacOSMutex : public Mutex {
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public:
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MacOSMutex() {
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pthread_mutexattr_t attr;
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pthread_mutexattr_init(&attr);
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pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE);
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pthread_mutex_init(&mutex_, &attr);
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}
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~MacOSMutex() { pthread_mutex_destroy(&mutex_); }
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int Lock() { return pthread_mutex_lock(&mutex_); }
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int Unlock() { return pthread_mutex_unlock(&mutex_); }
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private:
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pthread_mutex_t mutex_;
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};
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Mutex* OS::CreateMutex() {
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return new MacOSMutex();
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}
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class MacOSSemaphore : public Semaphore {
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public:
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explicit MacOSSemaphore(int count) {
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semaphore_create(mach_task_self(), &semaphore_, SYNC_POLICY_FIFO, count);
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}
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~MacOSSemaphore() {
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semaphore_destroy(mach_task_self(), semaphore_);
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}
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// The MacOS mach semaphore documentation claims it does not have spurious
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// wakeups, the way pthreads semaphores do. So the code from the linux
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// platform is not needed here.
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void Wait() { semaphore_wait(semaphore_); }
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bool Wait(int timeout);
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void Signal() { semaphore_signal(semaphore_); }
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private:
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semaphore_t semaphore_;
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};
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bool MacOSSemaphore::Wait(int timeout) {
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mach_timespec_t ts;
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ts.tv_sec = timeout / 1000000;
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ts.tv_nsec = (timeout % 1000000) * 1000;
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return semaphore_timedwait(semaphore_, ts) != KERN_OPERATION_TIMED_OUT;
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}
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Semaphore* OS::CreateSemaphore(int count) {
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return new MacOSSemaphore(count);
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}
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#ifdef ENABLE_LOGGING_AND_PROFILING
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class Sampler::PlatformData : public Malloced {
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public:
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explicit PlatformData(Sampler* sampler)
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: sampler_(sampler),
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task_self_(mach_task_self()),
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profiled_thread_(0),
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sampler_thread_(0) {
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}
|
|
|
|
Sampler* sampler_;
|
|
// Note: for profiled_thread_ Mach primitives are used instead of PThread's
|
|
// because the latter doesn't provide thread manipulation primitives required.
|
|
// For details, consult "Mac OS X Internals" book, Section 7.3.
|
|
mach_port_t task_self_;
|
|
thread_act_t profiled_thread_;
|
|
pthread_t sampler_thread_;
|
|
|
|
// Sampler thread handler.
|
|
void Runner() {
|
|
// Loop until the sampler is disengaged, keeping the specified samling freq.
|
|
for ( ; sampler_->IsActive(); OS::Sleep(sampler_->interval_)) {
|
|
TickSample sample_obj;
|
|
TickSample* sample = CpuProfiler::TickSampleEvent();
|
|
if (sample == NULL) sample = &sample_obj;
|
|
|
|
// We always sample the VM state.
|
|
sample->state = VMState::current_state();
|
|
// If profiling, we record the pc and sp of the profiled thread.
|
|
if (sampler_->IsProfiling()
|
|
&& KERN_SUCCESS == thread_suspend(profiled_thread_)) {
|
|
#if V8_HOST_ARCH_X64
|
|
thread_state_flavor_t flavor = x86_THREAD_STATE64;
|
|
x86_thread_state64_t state;
|
|
mach_msg_type_number_t count = x86_THREAD_STATE64_COUNT;
|
|
#if __DARWIN_UNIX03
|
|
#define REGISTER_FIELD(name) __r ## name
|
|
#else
|
|
#define REGISTER_FIELD(name) r ## name
|
|
#endif // __DARWIN_UNIX03
|
|
#elif V8_HOST_ARCH_IA32
|
|
thread_state_flavor_t flavor = i386_THREAD_STATE;
|
|
i386_thread_state_t state;
|
|
mach_msg_type_number_t count = i386_THREAD_STATE_COUNT;
|
|
#if __DARWIN_UNIX03
|
|
#define REGISTER_FIELD(name) __e ## name
|
|
#else
|
|
#define REGISTER_FIELD(name) e ## name
|
|
#endif // __DARWIN_UNIX03
|
|
#else
|
|
#error Unsupported Mac OS X host architecture.
|
|
#endif // V8_HOST_ARCH
|
|
|
|
if (thread_get_state(profiled_thread_,
|
|
flavor,
|
|
reinterpret_cast<natural_t*>(&state),
|
|
&count) == KERN_SUCCESS) {
|
|
sample->pc = reinterpret_cast<Address>(state.REGISTER_FIELD(ip));
|
|
sample->sp = reinterpret_cast<Address>(state.REGISTER_FIELD(sp));
|
|
sample->fp = reinterpret_cast<Address>(state.REGISTER_FIELD(bp));
|
|
sampler_->SampleStack(sample);
|
|
}
|
|
thread_resume(profiled_thread_);
|
|
}
|
|
|
|
// Invoke tick handler with program counter and stack pointer.
|
|
sampler_->Tick(sample);
|
|
}
|
|
}
|
|
};
|
|
|
|
#undef REGISTER_FIELD
|
|
|
|
|
|
// Entry point for sampler thread.
|
|
static void* SamplerEntry(void* arg) {
|
|
Sampler::PlatformData* data =
|
|
reinterpret_cast<Sampler::PlatformData*>(arg);
|
|
data->Runner();
|
|
return 0;
|
|
}
|
|
|
|
|
|
Sampler::Sampler(int interval, bool profiling)
|
|
: interval_(interval), profiling_(profiling), active_(false) {
|
|
data_ = new PlatformData(this);
|
|
}
|
|
|
|
|
|
Sampler::~Sampler() {
|
|
delete data_;
|
|
}
|
|
|
|
|
|
void Sampler::Start() {
|
|
// If we are profiling, we need to be able to access the calling
|
|
// thread.
|
|
if (IsProfiling()) {
|
|
data_->profiled_thread_ = mach_thread_self();
|
|
}
|
|
|
|
// Create sampler thread with high priority.
|
|
// According to POSIX spec, when SCHED_FIFO policy is used, a thread
|
|
// runs until it exits or blocks.
|
|
pthread_attr_t sched_attr;
|
|
sched_param fifo_param;
|
|
pthread_attr_init(&sched_attr);
|
|
pthread_attr_setinheritsched(&sched_attr, PTHREAD_EXPLICIT_SCHED);
|
|
pthread_attr_setschedpolicy(&sched_attr, SCHED_FIFO);
|
|
fifo_param.sched_priority = sched_get_priority_max(SCHED_FIFO);
|
|
pthread_attr_setschedparam(&sched_attr, &fifo_param);
|
|
|
|
active_ = true;
|
|
pthread_create(&data_->sampler_thread_, &sched_attr, SamplerEntry, data_);
|
|
}
|
|
|
|
|
|
void Sampler::Stop() {
|
|
// Seting active to false triggers termination of the sampler
|
|
// thread.
|
|
active_ = false;
|
|
|
|
// Wait for sampler thread to terminate.
|
|
pthread_join(data_->sampler_thread_, NULL);
|
|
|
|
// Deallocate Mach port for thread.
|
|
if (IsProfiling()) {
|
|
mach_port_deallocate(data_->task_self_, data_->profiled_thread_);
|
|
}
|
|
}
|
|
|
|
#endif // ENABLE_LOGGING_AND_PROFILING
|
|
|
|
} } // namespace v8::internal
|