v8/src/platform-openbsd.cc
2013-09-23 14:11:59 +00:00

365 lines
11 KiB
C++

// 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 OpenBSD and NetBSD 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/time.h>
#include <sys/resource.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <stdlib.h>
#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
#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 {
const char* OS::LocalTimezone(double time) {
if (std::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));
}
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_ANON, -1, 0);
if (mbase == MAP_FAILED) {
LOG(i::Isolate::Current(),
StringEvent("OS::Allocate", "mmap failed"));
return NULL;
}
*allocated = msize;
return mbase;
}
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(0, 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(0, 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(Isolate* isolate) {
// 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));
// 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);
}
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(FLAG_gc_fake_mmap, "w+");
if (f == NULL) {
OS::PrintError("Failed to open %s\n", FLAG_gc_fake_mmap);
OS::Abort();
}
void* addr = mmap(NULL, size, PROT_READ | PROT_EXEC, MAP_PRIVATE,
fileno(f), 0);
ASSERT(addr != MAP_FAILED);
OS::Free(addr, size);
fclose(f);
}
// 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_ANON | 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);
}
bool VirtualMemory::Guard(void* address) {
OS::Guard(address, OS::CommitPageSize());
return true;
}
void* VirtualMemory::ReserveRegion(size_t size) {
void* result = mmap(OS::GetRandomMmapAddr(),
size,
PROT_NONE,
MAP_PRIVATE | MAP_ANON | 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_ANON | MAP_FIXED,
kMmapFd,
kMmapFdOffset)) {
return false;
}
return true;
}
bool VirtualMemory::UncommitRegion(void* base, size_t size) {
return mmap(base,
size,
PROT_NONE,
MAP_PRIVATE | MAP_ANON | MAP_NORESERVE | MAP_FIXED,
kMmapFd,
kMmapFdOffset) != MAP_FAILED;
}
bool VirtualMemory::ReleaseRegion(void* base, size_t size) {
return munmap(base, size) == 0;
}
bool VirtualMemory::HasLazyCommits() {
// TODO(alph): implement for the platform.
return false;
}
} } // namespace v8::internal