| // Copyright 2012 the V8 project authors. All rights reserved. |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions are |
| // met: |
| // |
| // * Redistributions of source code must retain the above copyright |
| // notice, this list of conditions and the following disclaimer. |
| // * Redistributions in binary form must reproduce the above |
| // copyright notice, this list of conditions and the following |
| // disclaimer in the documentation and/or other materials provided |
| // with the distribution. |
| // * Neither the name of Google Inc. nor the names of its |
| // contributors may be used to endorse or promote products derived |
| // from this software without specific prior written permission. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| // Platform specific code for Linux goes here. For the POSIX comaptible parts |
| // the implementation is in platform-posix.cc. |
| |
| #include <pthread.h> |
| #include <semaphore.h> |
| #include <signal.h> |
| #include <sys/prctl.h> |
| #include <sys/time.h> |
| #include <sys/resource.h> |
| #include <sys/syscall.h> |
| #include <sys/types.h> |
| #include <stdlib.h> |
| |
| // Ubuntu Dapper requires memory pages to be marked as |
| // executable. Otherwise, OS raises an exception when executing code |
| // in that page. |
| #include <sys/types.h> // mmap & munmap |
| #include <sys/mman.h> // mmap & munmap |
| #include <sys/stat.h> // open |
| #include <fcntl.h> // open |
| #include <unistd.h> // sysconf |
| #ifdef __GLIBC__ |
| #include <execinfo.h> // backtrace, backtrace_symbols |
| #endif // def __GLIBC__ |
| #include <strings.h> // index |
| #include <errno.h> |
| #include <stdarg.h> |
| |
| #undef MAP_TYPE |
| |
| #include "v8.h" |
| |
| #include "platform.h" |
| #include "v8threads.h" |
| #include "vm-state-inl.h" |
| |
| |
| namespace v8 { |
| namespace internal { |
| |
| // 0 is never a valid thread id on Linux since tids and pids share a |
| // name space and pid 0 is reserved (see man 2 kill). |
| static const pthread_t kNoThread = (pthread_t) 0; |
| |
| |
| double ceiling(double x) { |
| return ceil(x); |
| } |
| |
| |
| static Mutex* limit_mutex = NULL; |
| |
| |
| void OS::SetUp() { |
| // Seed the random number generator. We preserve microsecond resolution. |
| uint64_t seed = Ticks() ^ (getpid() << 16); |
| srandom(static_cast<unsigned int>(seed)); |
| limit_mutex = CreateMutex(); |
| |
| #ifdef __arm__ |
| // When running on ARM hardware check that the EABI used by V8 and |
| // by the C code is the same. |
| bool hard_float = OS::ArmUsingHardFloat(); |
| if (hard_float) { |
| #if !USE_EABI_HARDFLOAT |
| PrintF("ERROR: Binary compiled with -mfloat-abi=hard but without " |
| "-DUSE_EABI_HARDFLOAT\n"); |
| exit(1); |
| #endif |
| } else { |
| #if USE_EABI_HARDFLOAT |
| PrintF("ERROR: Binary not compiled with -mfloat-abi=hard but with " |
| "-DUSE_EABI_HARDFLOAT\n"); |
| exit(1); |
| #endif |
| } |
| #endif |
| } |
| |
| |
| uint64_t OS::CpuFeaturesImpliedByPlatform() { |
| return 0; // Linux runs on anything. |
| } |
| |
| |
| #ifdef __arm__ |
| static bool CPUInfoContainsString(const char * search_string) { |
| const char* file_name = "/proc/cpuinfo"; |
| // This is written as a straight shot one pass parser |
| // and not using STL string and ifstream because, |
| // on Linux, it's reading from a (non-mmap-able) |
| // character special device. |
| FILE* f = NULL; |
| const char* what = search_string; |
| |
| if (NULL == (f = fopen(file_name, "r"))) |
| return false; |
| |
| int k; |
| while (EOF != (k = fgetc(f))) { |
| if (k == *what) { |
| ++what; |
| while ((*what != '\0') && (*what == fgetc(f))) { |
| ++what; |
| } |
| if (*what == '\0') { |
| fclose(f); |
| return true; |
| } else { |
| what = search_string; |
| } |
| } |
| } |
| fclose(f); |
| |
| // Did not find string in the proc file. |
| return false; |
| } |
| |
| |
| bool OS::ArmCpuHasFeature(CpuFeature feature) { |
| const char* search_string = NULL; |
| // Simple detection of VFP at runtime for Linux. |
| // It is based on /proc/cpuinfo, which reveals hardware configuration |
| // to user-space applications. According to ARM (mid 2009), no similar |
| // facility is universally available on the ARM architectures, |
| // so it's up to individual OSes to provide such. |
| switch (feature) { |
| case VFP3: |
| search_string = "vfpv3"; |
| break; |
| case ARMv7: |
| search_string = "ARMv7"; |
| break; |
| default: |
| UNREACHABLE(); |
| } |
| |
| if (CPUInfoContainsString(search_string)) { |
| return true; |
| } |
| |
| if (feature == VFP3) { |
| // Some old kernels will report vfp not vfpv3. Here we make a last attempt |
| // to detect vfpv3 by checking for vfp *and* neon, since neon is only |
| // available on architectures with vfpv3. |
| // Checking neon on its own is not enough as it is possible to have neon |
| // without vfp. |
| if (CPUInfoContainsString("vfp") && CPUInfoContainsString("neon")) { |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| |
| |
| // Simple helper function to detect whether the C code is compiled with |
| // option -mfloat-abi=hard. The register d0 is loaded with 1.0 and the register |
| // pair r0, r1 is loaded with 0.0. If -mfloat-abi=hard is pased to GCC then |
| // calling this will return 1.0 and otherwise 0.0. |
| static void ArmUsingHardFloatHelper() { |
| asm("mov r0, #0"); |
| #if defined(__VFP_FP__) && !defined(__SOFTFP__) |
| // Load 0x3ff00000 into r1 using instructions available in both ARM |
| // and Thumb mode. |
| asm("mov r1, #3"); |
| asm("mov r2, #255"); |
| asm("lsl r1, r1, #8"); |
| asm("orr r1, r1, r2"); |
| asm("lsl r1, r1, #20"); |
| // For vmov d0, r0, r1 use ARM mode. |
| #ifdef __thumb__ |
| asm volatile( |
| "@ Enter ARM Mode \n\t" |
| " adr r3, 1f \n\t" |
| " bx r3 \n\t" |
| " .ALIGN 4 \n\t" |
| " .ARM \n" |
| "1: vmov d0, r0, r1 \n\t" |
| "@ Enter THUMB Mode\n\t" |
| " adr r3, 2f+1 \n\t" |
| " bx r3 \n\t" |
| " .THUMB \n" |
| "2: \n\t"); |
| #else |
| asm("vmov d0, r0, r1"); |
| #endif // __thumb__ |
| #endif // defined(__VFP_FP__) && !defined(__SOFTFP__) |
| asm("mov r1, #0"); |
| } |
| |
| |
| bool OS::ArmUsingHardFloat() { |
| // Cast helper function from returning void to returning double. |
| typedef double (*F)(); |
| F f = FUNCTION_CAST<F>(FUNCTION_ADDR(ArmUsingHardFloatHelper)); |
| return f() == 1.0; |
| } |
| #endif // def __arm__ |
| |
| |
| #ifdef __mips__ |
| bool OS::MipsCpuHasFeature(CpuFeature feature) { |
| const char* search_string = NULL; |
| const char* file_name = "/proc/cpuinfo"; |
| // Simple detection of FPU at runtime for Linux. |
| // It is based on /proc/cpuinfo, which reveals hardware configuration |
| // to user-space applications. According to MIPS (early 2010), no similar |
| // facility is universally available on the MIPS architectures, |
| // so it's up to individual OSes to provide such. |
| // |
| // This is written as a straight shot one pass parser |
| // and not using STL string and ifstream because, |
| // on Linux, it's reading from a (non-mmap-able) |
| // character special device. |
| |
| switch (feature) { |
| case FPU: |
| search_string = "FPU"; |
| break; |
| default: |
| UNREACHABLE(); |
| } |
| |
| FILE* f = NULL; |
| const char* what = search_string; |
| |
| if (NULL == (f = fopen(file_name, "r"))) |
| return false; |
| |
| int k; |
| while (EOF != (k = fgetc(f))) { |
| if (k == *what) { |
| ++what; |
| while ((*what != '\0') && (*what == fgetc(f))) { |
| ++what; |
| } |
| if (*what == '\0') { |
| fclose(f); |
| return true; |
| } else { |
| what = search_string; |
| } |
| } |
| } |
| fclose(f); |
| |
| // Did not find string in the proc file. |
| return false; |
| } |
| #endif // def __mips__ |
| |
| |
| int OS::ActivationFrameAlignment() { |
| #ifdef V8_TARGET_ARCH_ARM |
| // On EABI ARM targets this is required for fp correctness in the |
| // runtime system. |
| return 8; |
| #elif V8_TARGET_ARCH_MIPS |
| return 8; |
| #endif |
| // With gcc 4.4 the tree vectorization optimizer can generate code |
| // that requires 16 byte alignment such as movdqa on x86. |
| return 16; |
| } |
| |
| |
| void OS::ReleaseStore(volatile AtomicWord* ptr, AtomicWord value) { |
| #if (defined(V8_TARGET_ARCH_ARM) && defined(__arm__)) || \ |
| (defined(V8_TARGET_ARCH_MIPS) && defined(__mips__)) |
| // Only use on ARM or MIPS hardware. |
| MemoryBarrier(); |
| #else |
| __asm__ __volatile__("" : : : "memory"); |
| // An x86 store acts as a release barrier. |
| #endif |
| *ptr = value; |
| } |
| |
| |
| const char* OS::LocalTimezone(double time) { |
| if (isnan(time)) return ""; |
| time_t tv = static_cast<time_t>(floor(time/msPerSecond)); |
| struct tm* t = localtime(&tv); |
| if (NULL == t) return ""; |
| return t->tm_zone; |
| } |
| |
| |
| double OS::LocalTimeOffset() { |
| time_t tv = time(NULL); |
| struct tm* t = localtime(&tv); |
| // tm_gmtoff includes any daylight savings offset, so subtract it. |
| return static_cast<double>(t->tm_gmtoff * msPerSecond - |
| (t->tm_isdst > 0 ? 3600 * msPerSecond : 0)); |
| } |
| |
| |
| // We keep the lowest and highest addresses mapped as a quick way of |
| // determining that pointers are outside the heap (used mostly in assertions |
| // and verification). The estimate is conservative, i.e., not all addresses in |
| // 'allocated' space are actually allocated to our heap. The range is |
| // [lowest, highest), inclusive on the low and and exclusive on the high end. |
| static void* lowest_ever_allocated = reinterpret_cast<void*>(-1); |
| static void* highest_ever_allocated = reinterpret_cast<void*>(0); |
| |
| |
| static void UpdateAllocatedSpaceLimits(void* address, int size) { |
| ASSERT(limit_mutex != NULL); |
| ScopedLock lock(limit_mutex); |
| |
| lowest_ever_allocated = Min(lowest_ever_allocated, address); |
| highest_ever_allocated = |
| Max(highest_ever_allocated, |
| reinterpret_cast<void*>(reinterpret_cast<char*>(address) + size)); |
| } |
| |
| |
| bool OS::IsOutsideAllocatedSpace(void* address) { |
| return address < lowest_ever_allocated || address >= highest_ever_allocated; |
| } |
| |
| |
| size_t OS::AllocateAlignment() { |
| return sysconf(_SC_PAGESIZE); |
| } |
| |
| |
| void* OS::Allocate(const size_t requested, |
| size_t* allocated, |
| bool is_executable) { |
| const size_t msize = RoundUp(requested, AllocateAlignment()); |
| int prot = PROT_READ | PROT_WRITE | (is_executable ? PROT_EXEC : 0); |
| void* addr = OS::GetRandomMmapAddr(); |
| void* mbase = mmap(addr, msize, prot, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); |
| if (mbase == MAP_FAILED) { |
| LOG(i::Isolate::Current(), |
| StringEvent("OS::Allocate", "mmap failed")); |
| return NULL; |
| } |
| *allocated = msize; |
| UpdateAllocatedSpaceLimits(mbase, msize); |
| return mbase; |
| } |
| |
| |
| void OS::Free(void* address, const size_t size) { |
| // TODO(1240712): munmap has a return value which is ignored here. |
| int result = munmap(address, size); |
| USE(result); |
| ASSERT(result == 0); |
| } |
| |
| |
| void OS::Sleep(int milliseconds) { |
| unsigned int ms = static_cast<unsigned int>(milliseconds); |
| usleep(1000 * ms); |
| } |
| |
| |
| void OS::Abort() { |
| // Redirect to std abort to signal abnormal program termination. |
| abort(); |
| } |
| |
| |
| void OS::DebugBreak() { |
| // TODO(lrn): Introduce processor define for runtime system (!= V8_ARCH_x, |
| // which is the architecture of generated code). |
| #if (defined(__arm__) || defined(__thumb__)) |
| # if defined(CAN_USE_ARMV5_INSTRUCTIONS) |
| asm("bkpt 0"); |
| # endif |
| #elif defined(__mips__) |
| asm("break"); |
| #else |
| asm("int $3"); |
| #endif |
| } |
| |
| |
| class PosixMemoryMappedFile : public OS::MemoryMappedFile { |
| public: |
| PosixMemoryMappedFile(FILE* file, void* memory, int size) |
| : file_(file), memory_(memory), size_(size) { } |
| virtual ~PosixMemoryMappedFile(); |
| virtual void* memory() { return memory_; } |
| virtual int size() { return size_; } |
| private: |
| FILE* file_; |
| void* memory_; |
| int size_; |
| }; |
| |
| |
| OS::MemoryMappedFile* OS::MemoryMappedFile::open(const char* name) { |
| FILE* file = fopen(name, "r+"); |
| if (file == NULL) return NULL; |
| |
| fseek(file, 0, SEEK_END); |
| int size = ftell(file); |
| |
| void* memory = |
| mmap(OS::GetRandomMmapAddr(), |
| size, |
| PROT_READ | PROT_WRITE, |
| MAP_SHARED, |
| fileno(file), |
| 0); |
| return new PosixMemoryMappedFile(file, memory, size); |
| } |
| |
| |
| OS::MemoryMappedFile* OS::MemoryMappedFile::create(const char* name, int size, |
| void* initial) { |
| FILE* file = fopen(name, "w+"); |
| if (file == NULL) return NULL; |
| int result = fwrite(initial, size, 1, file); |
| if (result < 1) { |
| fclose(file); |
| return NULL; |
| } |
| void* memory = |
| mmap(OS::GetRandomMmapAddr(), |
| size, |
| PROT_READ | PROT_WRITE, |
| MAP_SHARED, |
| fileno(file), |
| 0); |
| return new PosixMemoryMappedFile(file, memory, size); |
| } |
| |
| |
| PosixMemoryMappedFile::~PosixMemoryMappedFile() { |
| if (memory_) OS::Free(memory_, size_); |
| fclose(file_); |
| } |
| |
| |
| void OS::LogSharedLibraryAddresses() { |
| // This function assumes that the layout of the file is as follows: |
| // hex_start_addr-hex_end_addr rwxp <unused data> [binary_file_name] |
| // If we encounter an unexpected situation we abort scanning further entries. |
| FILE* fp = fopen("/proc/self/maps", "r"); |
| if (fp == NULL) return; |
| |
| // Allocate enough room to be able to store a full file name. |
| const int kLibNameLen = FILENAME_MAX + 1; |
| char* lib_name = reinterpret_cast<char*>(malloc(kLibNameLen)); |
| |
| i::Isolate* isolate = ISOLATE; |
| // This loop will terminate once the scanning hits an EOF. |
| while (true) { |
| uintptr_t start, end; |
| char attr_r, attr_w, attr_x, attr_p; |
| // Parse the addresses and permission bits at the beginning of the line. |
| if (fscanf(fp, "%" V8PRIxPTR "-%" V8PRIxPTR, &start, &end) != 2) break; |
| if (fscanf(fp, " %c%c%c%c", &attr_r, &attr_w, &attr_x, &attr_p) != 4) break; |
| |
| int c; |
| if (attr_r == 'r' && attr_w != 'w' && attr_x == 'x') { |
| // Found a read-only executable entry. Skip characters until we reach |
| // the beginning of the filename or the end of the line. |
| do { |
| c = getc(fp); |
| } while ((c != EOF) && (c != '\n') && (c != '/')); |
| if (c == EOF) break; // EOF: Was unexpected, just exit. |
| |
| // Process the filename if found. |
| if (c == '/') { |
| ungetc(c, fp); // Push the '/' back into the stream to be read below. |
| |
| // Read to the end of the line. Exit if the read fails. |
| if (fgets(lib_name, kLibNameLen, fp) == NULL) break; |
| |
| // Drop the newline character read by fgets. We do not need to check |
| // for a zero-length string because we know that we at least read the |
| // '/' character. |
| lib_name[strlen(lib_name) - 1] = '\0'; |
| } else { |
| // No library name found, just record the raw address range. |
| snprintf(lib_name, kLibNameLen, |
| "%08" V8PRIxPTR "-%08" V8PRIxPTR, start, end); |
| } |
| LOG(isolate, SharedLibraryEvent(lib_name, start, end)); |
| } else { |
| // Entry not describing executable data. Skip to end of line to set up |
| // reading the next entry. |
| do { |
| c = getc(fp); |
| } while ((c != EOF) && (c != '\n')); |
| if (c == EOF) break; |
| } |
| } |
| free(lib_name); |
| fclose(fp); |
| } |
| |
| |
| static const char kGCFakeMmap[] = "/tmp/__v8_gc__"; |
| |
| |
| void OS::SignalCodeMovingGC() { |
| // Support for ll_prof.py. |
| // |
| // The Linux profiler built into the kernel logs all mmap's with |
| // PROT_EXEC so that analysis tools can properly attribute ticks. We |
| // do a mmap with a name known by ll_prof.py and immediately munmap |
| // it. This injects a GC marker into the stream of events generated |
| // by the kernel and allows us to synchronize V8 code log and the |
| // kernel log. |
| int size = sysconf(_SC_PAGESIZE); |
| FILE* f = fopen(kGCFakeMmap, "w+"); |
| void* addr = mmap(OS::GetRandomMmapAddr(), |
| size, |
| PROT_READ | PROT_EXEC, |
| MAP_PRIVATE, |
| fileno(f), |
| 0); |
| ASSERT(addr != MAP_FAILED); |
| OS::Free(addr, size); |
| fclose(f); |
| } |
| |
| |
| int OS::StackWalk(Vector<OS::StackFrame> frames) { |
| // backtrace is a glibc extension. |
| #ifdef __GLIBC__ |
| int frames_size = frames.length(); |
| ScopedVector<void*> addresses(frames_size); |
| |
| int frames_count = backtrace(addresses.start(), frames_size); |
| |
| char** symbols = backtrace_symbols(addresses.start(), frames_count); |
| if (symbols == NULL) { |
| return kStackWalkError; |
| } |
| |
| for (int i = 0; i < frames_count; i++) { |
| frames[i].address = addresses[i]; |
| // Format a text representation of the frame based on the information |
| // available. |
| SNPrintF(MutableCStrVector(frames[i].text, kStackWalkMaxTextLen), |
| "%s", |
| symbols[i]); |
| // Make sure line termination is in place. |
| frames[i].text[kStackWalkMaxTextLen - 1] = '\0'; |
| } |
| |
| free(symbols); |
| |
| return frames_count; |
| #else // ndef __GLIBC__ |
| return 0; |
| #endif // ndef __GLIBC__ |
| } |
| |
| |
| // Constants used for mmap. |
| static const int kMmapFd = -1; |
| static const int kMmapFdOffset = 0; |
| |
| VirtualMemory::VirtualMemory() : address_(NULL), size_(0) { } |
| |
| VirtualMemory::VirtualMemory(size_t size) { |
| address_ = ReserveRegion(size); |
| size_ = size; |
| } |
| |
| |
| VirtualMemory::VirtualMemory(size_t size, size_t alignment) |
| : address_(NULL), size_(0) { |
| ASSERT(IsAligned(alignment, static_cast<intptr_t>(OS::AllocateAlignment()))); |
| size_t request_size = RoundUp(size + alignment, |
| static_cast<intptr_t>(OS::AllocateAlignment())); |
| void* reservation = mmap(OS::GetRandomMmapAddr(), |
| request_size, |
| PROT_NONE, |
| MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE, |
| kMmapFd, |
| kMmapFdOffset); |
| if (reservation == MAP_FAILED) return; |
| |
| Address base = static_cast<Address>(reservation); |
| Address aligned_base = RoundUp(base, alignment); |
| ASSERT_LE(base, aligned_base); |
| |
| // Unmap extra memory reserved before and after the desired block. |
| if (aligned_base != base) { |
| size_t prefix_size = static_cast<size_t>(aligned_base - base); |
| OS::Free(base, prefix_size); |
| request_size -= prefix_size; |
| } |
| |
| size_t aligned_size = RoundUp(size, OS::AllocateAlignment()); |
| ASSERT_LE(aligned_size, request_size); |
| |
| if (aligned_size != request_size) { |
| size_t suffix_size = request_size - aligned_size; |
| OS::Free(aligned_base + aligned_size, suffix_size); |
| request_size -= suffix_size; |
| } |
| |
| ASSERT(aligned_size == request_size); |
| |
| address_ = static_cast<void*>(aligned_base); |
| size_ = aligned_size; |
| } |
| |
| |
| VirtualMemory::~VirtualMemory() { |
| if (IsReserved()) { |
| bool result = ReleaseRegion(address(), size()); |
| ASSERT(result); |
| USE(result); |
| } |
| } |
| |
| |
| bool VirtualMemory::IsReserved() { |
| return address_ != NULL; |
| } |
| |
| |
| void VirtualMemory::Reset() { |
| address_ = NULL; |
| size_ = 0; |
| } |
| |
| |
| bool VirtualMemory::Commit(void* address, size_t size, bool is_executable) { |
| return CommitRegion(address, size, is_executable); |
| } |
| |
| |
| bool VirtualMemory::Uncommit(void* address, size_t size) { |
| return UncommitRegion(address, size); |
| } |
| |
| |
| void* VirtualMemory::ReserveRegion(size_t size) { |
| void* result = mmap(OS::GetRandomMmapAddr(), |
| size, |
| PROT_NONE, |
| MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE, |
| kMmapFd, |
| kMmapFdOffset); |
| |
| if (result == MAP_FAILED) return NULL; |
| |
| return result; |
| } |
| |
| |
| bool VirtualMemory::CommitRegion(void* base, size_t size, bool is_executable) { |
| int prot = PROT_READ | PROT_WRITE | (is_executable ? PROT_EXEC : 0); |
| if (MAP_FAILED == mmap(base, |
| size, |
| prot, |
| MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, |
| kMmapFd, |
| kMmapFdOffset)) { |
| return false; |
| } |
| |
| UpdateAllocatedSpaceLimits(base, size); |
| return true; |
| } |
| |
| |
| bool VirtualMemory::UncommitRegion(void* base, size_t size) { |
| return mmap(base, |
| size, |
| PROT_NONE, |
| MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE | MAP_FIXED, |
| kMmapFd, |
| kMmapFdOffset) != MAP_FAILED; |
| } |
| |
| |
| bool VirtualMemory::ReleaseRegion(void* base, size_t size) { |
| return munmap(base, size) == 0; |
| } |
| |
| |
| class Thread::PlatformData : public Malloced { |
| public: |
| PlatformData() : thread_(kNoThread) {} |
| |
| pthread_t thread_; // Thread handle for pthread. |
| }; |
| |
| Thread::Thread(const Options& options) |
| : data_(new PlatformData()), |
| stack_size_(options.stack_size()) { |
| set_name(options.name()); |
| } |
| |
| |
| Thread::~Thread() { |
| delete data_; |
| } |
| |
| |
| static void* ThreadEntry(void* arg) { |
| Thread* thread = reinterpret_cast<Thread*>(arg); |
| // This is also initialized by the first argument to pthread_create() but we |
| // don't know which thread will run first (the original thread or the new |
| // one) so we initialize it here too. |
| #ifdef PR_SET_NAME |
| prctl(PR_SET_NAME, |
| reinterpret_cast<unsigned long>(thread->name()), // NOLINT |
| 0, 0, 0); |
| #endif |
| thread->data()->thread_ = pthread_self(); |
| ASSERT(thread->data()->thread_ != kNoThread); |
| thread->Run(); |
| return NULL; |
| } |
| |
| |
| void Thread::set_name(const char* name) { |
| strncpy(name_, name, sizeof(name_)); |
| name_[sizeof(name_) - 1] = '\0'; |
| } |
| |
| |
| void Thread::Start() { |
| pthread_attr_t* attr_ptr = NULL; |
| pthread_attr_t attr; |
| if (stack_size_ > 0) { |
| pthread_attr_init(&attr); |
| pthread_attr_setstacksize(&attr, static_cast<size_t>(stack_size_)); |
| attr_ptr = &attr; |
| } |
| int result = pthread_create(&data_->thread_, attr_ptr, ThreadEntry, this); |
| CHECK_EQ(0, result); |
| ASSERT(data_->thread_ != kNoThread); |
| } |
| |
| |
| void Thread::Join() { |
| pthread_join(data_->thread_, NULL); |
| } |
| |
| |
| Thread::LocalStorageKey Thread::CreateThreadLocalKey() { |
| pthread_key_t key; |
| int result = pthread_key_create(&key, NULL); |
| USE(result); |
| ASSERT(result == 0); |
| return static_cast<LocalStorageKey>(key); |
| } |
| |
| |
| void Thread::DeleteThreadLocalKey(LocalStorageKey key) { |
| pthread_key_t pthread_key = static_cast<pthread_key_t>(key); |
| int result = pthread_key_delete(pthread_key); |
| USE(result); |
| ASSERT(result == 0); |
| } |
| |
| |
| void* Thread::GetThreadLocal(LocalStorageKey key) { |
| pthread_key_t pthread_key = static_cast<pthread_key_t>(key); |
| return pthread_getspecific(pthread_key); |
| } |
| |
| |
| void Thread::SetThreadLocal(LocalStorageKey key, void* value) { |
| pthread_key_t pthread_key = static_cast<pthread_key_t>(key); |
| pthread_setspecific(pthread_key, value); |
| } |
| |
| |
| void Thread::YieldCPU() { |
| sched_yield(); |
| } |
| |
| |
| class LinuxMutex : public Mutex { |
| public: |
| LinuxMutex() { |
| pthread_mutexattr_t attrs; |
| int result = pthread_mutexattr_init(&attrs); |
| ASSERT(result == 0); |
| result = pthread_mutexattr_settype(&attrs, PTHREAD_MUTEX_RECURSIVE); |
| ASSERT(result == 0); |
| result = pthread_mutex_init(&mutex_, &attrs); |
| ASSERT(result == 0); |
| USE(result); |
| } |
| |
| virtual ~LinuxMutex() { pthread_mutex_destroy(&mutex_); } |
| |
| virtual int Lock() { |
| int result = pthread_mutex_lock(&mutex_); |
| return result; |
| } |
| |
| virtual int Unlock() { |
| int result = pthread_mutex_unlock(&mutex_); |
| return result; |
| } |
| |
| virtual bool TryLock() { |
| int result = pthread_mutex_trylock(&mutex_); |
| // Return false if the lock is busy and locking failed. |
| if (result == EBUSY) { |
| return false; |
| } |
| ASSERT(result == 0); // Verify no other errors. |
| return true; |
| } |
| |
| private: |
| pthread_mutex_t mutex_; // Pthread mutex for POSIX platforms. |
| }; |
| |
| |
| Mutex* OS::CreateMutex() { |
| return new LinuxMutex(); |
| } |
| |
| |
| class LinuxSemaphore : public Semaphore { |
| public: |
| explicit LinuxSemaphore(int count) { sem_init(&sem_, 0, count); } |
| virtual ~LinuxSemaphore() { sem_destroy(&sem_); } |
| |
| virtual void Wait(); |
| virtual bool Wait(int timeout); |
| virtual void Signal() { sem_post(&sem_); } |
| private: |
| sem_t sem_; |
| }; |
| |
| |
| void LinuxSemaphore::Wait() { |
| while (true) { |
| int result = sem_wait(&sem_); |
| if (result == 0) return; // Successfully got semaphore. |
| CHECK(result == -1 && errno == EINTR); // Signal caused spurious wakeup. |
| } |
| } |
| |
| |
| #ifndef TIMEVAL_TO_TIMESPEC |
| #define TIMEVAL_TO_TIMESPEC(tv, ts) do { \ |
| (ts)->tv_sec = (tv)->tv_sec; \ |
| (ts)->tv_nsec = (tv)->tv_usec * 1000; \ |
| } while (false) |
| #endif |
| |
| |
| bool LinuxSemaphore::Wait(int timeout) { |
| const long kOneSecondMicros = 1000000; // NOLINT |
| |
| // Split timeout into second and nanosecond parts. |
| struct timeval delta; |
| delta.tv_usec = timeout % kOneSecondMicros; |
| delta.tv_sec = timeout / kOneSecondMicros; |
| |
| struct timeval current_time; |
| // Get the current time. |
| if (gettimeofday(¤t_time, NULL) == -1) { |
| return false; |
| } |
| |
| // Calculate time for end of timeout. |
| struct timeval end_time; |
| timeradd(¤t_time, &delta, &end_time); |
| |
| struct timespec ts; |
| TIMEVAL_TO_TIMESPEC(&end_time, &ts); |
| // Wait for semaphore signalled or timeout. |
| while (true) { |
| int result = sem_timedwait(&sem_, &ts); |
| if (result == 0) return true; // Successfully got semaphore. |
| if (result > 0) { |
| // For glibc prior to 2.3.4 sem_timedwait returns the error instead of -1. |
| errno = result; |
| result = -1; |
| } |
| if (result == -1 && errno == ETIMEDOUT) return false; // Timeout. |
| CHECK(result == -1 && errno == EINTR); // Signal caused spurious wakeup. |
| } |
| } |
| |
| |
| Semaphore* OS::CreateSemaphore(int count) { |
| return new LinuxSemaphore(count); |
| } |
| |
| |
| #if !defined(__GLIBC__) && (defined(__arm__) || defined(__thumb__)) |
| // Android runs a fairly new Linux kernel, so signal info is there, |
| // but the C library doesn't have the structs defined. |
| |
| struct sigcontext { |
| uint32_t trap_no; |
| uint32_t error_code; |
| uint32_t oldmask; |
| uint32_t gregs[16]; |
| uint32_t arm_cpsr; |
| uint32_t fault_address; |
| }; |
| typedef uint32_t __sigset_t; |
| typedef struct sigcontext mcontext_t; |
| typedef struct ucontext { |
| uint32_t uc_flags; |
| struct ucontext* uc_link; |
| stack_t uc_stack; |
| mcontext_t uc_mcontext; |
| __sigset_t uc_sigmask; |
| } ucontext_t; |
| enum ArmRegisters {R15 = 15, R13 = 13, R11 = 11}; |
| |
| #elif !defined(__GLIBC__) && defined(__mips__) |
| // MIPS version of sigcontext, for Android bionic. |
| struct sigcontext { |
| uint32_t regmask; |
| uint32_t status; |
| uint64_t pc; |
| uint64_t gregs[32]; |
| uint64_t fpregs[32]; |
| uint32_t acx; |
| uint32_t fpc_csr; |
| uint32_t fpc_eir; |
| uint32_t used_math; |
| uint32_t dsp; |
| uint64_t mdhi; |
| uint64_t mdlo; |
| uint32_t hi1; |
| uint32_t lo1; |
| uint32_t hi2; |
| uint32_t lo2; |
| uint32_t hi3; |
| uint32_t lo3; |
| }; |
| typedef uint32_t __sigset_t; |
| typedef struct sigcontext mcontext_t; |
| typedef struct ucontext { |
| uint32_t uc_flags; |
| struct ucontext* uc_link; |
| stack_t uc_stack; |
| mcontext_t uc_mcontext; |
| __sigset_t uc_sigmask; |
| } ucontext_t; |
| |
| #endif |
| |
| |
| static int GetThreadID() { |
| // Glibc doesn't provide a wrapper for gettid(2). |
| #if defined(ANDROID) |
| return syscall(__NR_gettid); |
| #else |
| return syscall(SYS_gettid); |
| #endif |
| } |
| |
| |
| static void ProfilerSignalHandler(int signal, siginfo_t* info, void* context) { |
| USE(info); |
| if (signal != SIGPROF) return; |
| Isolate* isolate = Isolate::UncheckedCurrent(); |
| if (isolate == NULL || !isolate->IsInitialized() || !isolate->IsInUse()) { |
| // We require a fully initialized and entered isolate. |
| return; |
| } |
| if (v8::Locker::IsActive() && |
| !isolate->thread_manager()->IsLockedByCurrentThread()) { |
| return; |
| } |
| |
| Sampler* sampler = isolate->logger()->sampler(); |
| if (sampler == NULL || !sampler->IsActive()) return; |
| |
| TickSample sample_obj; |
| TickSample* sample = CpuProfiler::TickSampleEvent(isolate); |
| if (sample == NULL) sample = &sample_obj; |
| |
| // Extracting the sample from the context is extremely machine dependent. |
| ucontext_t* ucontext = reinterpret_cast<ucontext_t*>(context); |
| mcontext_t& mcontext = ucontext->uc_mcontext; |
| sample->state = isolate->current_vm_state(); |
| #if V8_HOST_ARCH_IA32 |
| sample->pc = reinterpret_cast<Address>(mcontext.gregs[REG_EIP]); |
| sample->sp = reinterpret_cast<Address>(mcontext.gregs[REG_ESP]); |
| sample->fp = reinterpret_cast<Address>(mcontext.gregs[REG_EBP]); |
| #elif V8_HOST_ARCH_X64 |
| sample->pc = reinterpret_cast<Address>(mcontext.gregs[REG_RIP]); |
| sample->sp = reinterpret_cast<Address>(mcontext.gregs[REG_RSP]); |
| sample->fp = reinterpret_cast<Address>(mcontext.gregs[REG_RBP]); |
| #elif V8_HOST_ARCH_ARM |
| // An undefined macro evaluates to 0, so this applies to Android's Bionic also. |
| #if (__GLIBC__ < 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ <= 3)) |
| sample->pc = reinterpret_cast<Address>(mcontext.gregs[R15]); |
| sample->sp = reinterpret_cast<Address>(mcontext.gregs[R13]); |
| sample->fp = reinterpret_cast<Address>(mcontext.gregs[R11]); |
| #else |
| sample->pc = reinterpret_cast<Address>(mcontext.arm_pc); |
| sample->sp = reinterpret_cast<Address>(mcontext.arm_sp); |
| sample->fp = reinterpret_cast<Address>(mcontext.arm_fp); |
| #endif // (__GLIBC__ < 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ <= 3)) |
| #elif V8_HOST_ARCH_MIPS |
| sample->pc = reinterpret_cast<Address>(mcontext.pc); |
| sample->sp = reinterpret_cast<Address>(mcontext.gregs[29]); |
| sample->fp = reinterpret_cast<Address>(mcontext.gregs[30]); |
| #endif // V8_HOST_ARCH_* |
| sampler->SampleStack(sample); |
| sampler->Tick(sample); |
| } |
| |
| |
| class Sampler::PlatformData : public Malloced { |
| public: |
| PlatformData() : vm_tid_(GetThreadID()) {} |
| |
| int vm_tid() const { return vm_tid_; } |
| |
| private: |
| const int vm_tid_; |
| }; |
| |
| |
| class SignalSender : public Thread { |
| public: |
| enum SleepInterval { |
| HALF_INTERVAL, |
| FULL_INTERVAL |
| }; |
| |
| static const int kSignalSenderStackSize = 32 * KB; |
| |
| explicit SignalSender(int interval) |
| : Thread(Thread::Options("SignalSender", kSignalSenderStackSize)), |
| vm_tgid_(getpid()), |
| interval_(interval) {} |
| |
| static void InstallSignalHandler() { |
| struct sigaction sa; |
| sa.sa_sigaction = ProfilerSignalHandler; |
| sigemptyset(&sa.sa_mask); |
| sa.sa_flags = SA_RESTART | SA_SIGINFO; |
| signal_handler_installed_ = |
| (sigaction(SIGPROF, &sa, &old_signal_handler_) == 0); |
| } |
| |
| static void RestoreSignalHandler() { |
| if (signal_handler_installed_) { |
| sigaction(SIGPROF, &old_signal_handler_, 0); |
| signal_handler_installed_ = false; |
| } |
| } |
| |
| static void AddActiveSampler(Sampler* sampler) { |
| ScopedLock lock(mutex_); |
| SamplerRegistry::AddActiveSampler(sampler); |
| if (instance_ == NULL) { |
| // Start a thread that will send SIGPROF signal to VM threads, |
| // when CPU profiling will be enabled. |
| instance_ = new SignalSender(sampler->interval()); |
| instance_->Start(); |
| } else { |
| ASSERT(instance_->interval_ == sampler->interval()); |
| } |
| } |
| |
| static void RemoveActiveSampler(Sampler* sampler) { |
| ScopedLock lock(mutex_); |
| SamplerRegistry::RemoveActiveSampler(sampler); |
| if (SamplerRegistry::GetState() == SamplerRegistry::HAS_NO_SAMPLERS) { |
| RuntimeProfiler::StopRuntimeProfilerThreadBeforeShutdown(instance_); |
| delete instance_; |
| instance_ = NULL; |
| RestoreSignalHandler(); |
| } |
| } |
| |
| // Implement Thread::Run(). |
| virtual void Run() { |
| SamplerRegistry::State state; |
| while ((state = SamplerRegistry::GetState()) != |
| SamplerRegistry::HAS_NO_SAMPLERS) { |
| bool cpu_profiling_enabled = |
| (state == SamplerRegistry::HAS_CPU_PROFILING_SAMPLERS); |
| bool runtime_profiler_enabled = RuntimeProfiler::IsEnabled(); |
| if (cpu_profiling_enabled && !signal_handler_installed_) { |
| InstallSignalHandler(); |
| } else if (!cpu_profiling_enabled && signal_handler_installed_) { |
| RestoreSignalHandler(); |
| } |
| // When CPU profiling is enabled both JavaScript and C++ code is |
| // profiled. We must not suspend. |
| if (!cpu_profiling_enabled) { |
| if (rate_limiter_.SuspendIfNecessary()) continue; |
| } |
| if (cpu_profiling_enabled && runtime_profiler_enabled) { |
| if (!SamplerRegistry::IterateActiveSamplers(&DoCpuProfile, this)) { |
| return; |
| } |
| Sleep(HALF_INTERVAL); |
| if (!SamplerRegistry::IterateActiveSamplers(&DoRuntimeProfile, NULL)) { |
| return; |
| } |
| Sleep(HALF_INTERVAL); |
| } else { |
| if (cpu_profiling_enabled) { |
| if (!SamplerRegistry::IterateActiveSamplers(&DoCpuProfile, |
| this)) { |
| return; |
| } |
| } |
| if (runtime_profiler_enabled) { |
| if (!SamplerRegistry::IterateActiveSamplers(&DoRuntimeProfile, |
| NULL)) { |
| return; |
| } |
| } |
| Sleep(FULL_INTERVAL); |
| } |
| } |
| } |
| |
| static void DoCpuProfile(Sampler* sampler, void* raw_sender) { |
| if (!sampler->IsProfiling()) return; |
| SignalSender* sender = reinterpret_cast<SignalSender*>(raw_sender); |
| sender->SendProfilingSignal(sampler->platform_data()->vm_tid()); |
| } |
| |
| static void DoRuntimeProfile(Sampler* sampler, void* ignored) { |
| if (!sampler->isolate()->IsInitialized()) return; |
| sampler->isolate()->runtime_profiler()->NotifyTick(); |
| } |
| |
| void SendProfilingSignal(int tid) { |
| if (!signal_handler_installed_) return; |
| // Glibc doesn't provide a wrapper for tgkill(2). |
| #if defined(ANDROID) |
| syscall(__NR_tgkill, vm_tgid_, tid, SIGPROF); |
| #else |
| syscall(SYS_tgkill, vm_tgid_, tid, SIGPROF); |
| #endif |
| } |
| |
| void Sleep(SleepInterval full_or_half) { |
| // Convert ms to us and subtract 100 us to compensate delays |
| // occuring during signal delivery. |
| useconds_t interval = interval_ * 1000 - 100; |
| if (full_or_half == HALF_INTERVAL) interval /= 2; |
| #if defined(ANDROID) |
| usleep(interval); |
| #else |
| int result = usleep(interval); |
| #ifdef DEBUG |
| if (result != 0 && errno != EINTR) { |
| fprintf(stderr, |
| "SignalSender usleep error; interval = %u, errno = %d\n", |
| interval, |
| errno); |
| ASSERT(result == 0 || errno == EINTR); |
| } |
| #endif // DEBUG |
| USE(result); |
| #endif // ANDROID |
| } |
| |
| const int vm_tgid_; |
| const int interval_; |
| RuntimeProfilerRateLimiter rate_limiter_; |
| |
| // 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_ = OS::CreateMutex(); |
| SignalSender* SignalSender::instance_ = NULL; |
| struct sigaction SignalSender::old_signal_handler_; |
| bool SignalSender::signal_handler_installed_ = false; |
| |
| |
| 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); |
| } |
| |
| |
| } } // namespace v8::internal |