blob: e2df2ca43e52f8f2046b1311bed34e7e6713fbbf [file] [log] [blame]
// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "base/process_util.h"
#import <Cocoa/Cocoa.h>
#include <crt_externs.h>
#include <dlfcn.h>
#include <mach/mach.h>
#include <mach/mach_init.h>
#include <mach/mach_vm.h>
#include <mach/shared_region.h>
#include <mach/task.h>
#include <malloc/malloc.h>
#import <objc/runtime.h>
#include <spawn.h>
#include <sys/mman.h>
#include <sys/sysctl.h>
#include <sys/types.h>
#include <sys/utsname.h>
#include <sys/wait.h>
#include <new>
#include <string>
#include "base/debug/debugger.h"
#include "base/eintr_wrapper.h"
#include "base/hash_tables.h"
#include "base/logging.h"
#include "base/string_util.h"
#include "base/sys_info.h"
#include "base/sys_string_conversions.h"
#include "base/time.h"
#include "third_party/apple_apsl/CFBase.h"
#include "third_party/apple_apsl/malloc.h"
namespace base {
void RestoreDefaultExceptionHandler() {
// This function is tailored to remove the Breakpad exception handler.
// exception_mask matches s_exception_mask in
// breakpad/src/client/mac/handler/exception_handler.cc
const exception_mask_t exception_mask = EXC_MASK_BAD_ACCESS |
EXC_MASK_BAD_INSTRUCTION |
EXC_MASK_ARITHMETIC |
EXC_MASK_BREAKPOINT;
// Setting the exception port to MACH_PORT_NULL may not be entirely
// kosher to restore the default exception handler, but in practice,
// it results in the exception port being set to Apple Crash Reporter,
// the desired behavior.
task_set_exception_ports(mach_task_self(), exception_mask, MACH_PORT_NULL,
EXCEPTION_DEFAULT, THREAD_STATE_NONE);
}
ProcessIterator::ProcessIterator(const ProcessFilter* filter)
: index_of_kinfo_proc_(0),
filter_(filter) {
// Get a snapshot of all of my processes (yes, as we loop it can go stale, but
// but trying to find where we were in a constantly changing list is basically
// impossible.
int mib[] = { CTL_KERN, KERN_PROC, KERN_PROC_UID, geteuid() };
// Since more processes could start between when we get the size and when
// we get the list, we do a loop to keep trying until we get it.
bool done = false;
int try_num = 1;
const int max_tries = 10;
do {
// Get the size of the buffer
size_t len = 0;
if (sysctl(mib, arraysize(mib), NULL, &len, NULL, 0) < 0) {
LOG(ERROR) << "failed to get the size needed for the process list";
kinfo_procs_.resize(0);
done = true;
} else {
size_t num_of_kinfo_proc = len / sizeof(struct kinfo_proc);
// Leave some spare room for process table growth (more could show up
// between when we check and now)
num_of_kinfo_proc += 16;
kinfo_procs_.resize(num_of_kinfo_proc);
len = num_of_kinfo_proc * sizeof(struct kinfo_proc);
// Load the list of processes
if (sysctl(mib, arraysize(mib), &kinfo_procs_[0], &len, NULL, 0) < 0) {
// If we get a mem error, it just means we need a bigger buffer, so
// loop around again. Anything else is a real error and give up.
if (errno != ENOMEM) {
LOG(ERROR) << "failed to get the process list";
kinfo_procs_.resize(0);
done = true;
}
} else {
// Got the list, just make sure we're sized exactly right
size_t num_of_kinfo_proc = len / sizeof(struct kinfo_proc);
kinfo_procs_.resize(num_of_kinfo_proc);
done = true;
}
}
} while (!done && (try_num++ < max_tries));
if (!done) {
LOG(ERROR) << "failed to collect the process list in a few tries";
kinfo_procs_.resize(0);
}
}
ProcessIterator::~ProcessIterator() {
}
bool ProcessIterator::CheckForNextProcess() {
std::string data;
for (; index_of_kinfo_proc_ < kinfo_procs_.size(); ++index_of_kinfo_proc_) {
kinfo_proc& kinfo = kinfo_procs_[index_of_kinfo_proc_];
// Skip processes just awaiting collection
if ((kinfo.kp_proc.p_pid > 0) && (kinfo.kp_proc.p_stat == SZOMB))
continue;
int mib[] = { CTL_KERN, KERN_PROCARGS, kinfo.kp_proc.p_pid };
// Find out what size buffer we need.
size_t data_len = 0;
if (sysctl(mib, arraysize(mib), NULL, &data_len, NULL, 0) < 0) {
DVPLOG(1) << "failed to figure out the buffer size for a commandline";
continue;
}
data.resize(data_len);
if (sysctl(mib, arraysize(mib), &data[0], &data_len, NULL, 0) < 0) {
DVPLOG(1) << "failed to fetch a commandline";
continue;
}
// |data| contains all the command line parameters of the process, separated
// by blocks of one or more null characters. We tokenize |data| into a
// vector of strings using '\0' as a delimiter and populate
// |entry_.cmd_line_args_|.
std::string delimiters;
delimiters.push_back('\0');
Tokenize(data, delimiters, &entry_.cmd_line_args_);
// |data| starts with the full executable path followed by a null character.
// We search for the first instance of '\0' and extract everything before it
// to populate |entry_.exe_file_|.
size_t exec_name_end = data.find('\0');
if (exec_name_end == std::string::npos) {
LOG(ERROR) << "command line data didn't match expected format";
continue;
}
entry_.pid_ = kinfo.kp_proc.p_pid;
entry_.ppid_ = kinfo.kp_eproc.e_ppid;
entry_.gid_ = kinfo.kp_eproc.e_pgid;
size_t last_slash = data.rfind('/', exec_name_end);
if (last_slash == std::string::npos)
entry_.exe_file_.assign(data, 0, exec_name_end);
else
entry_.exe_file_.assign(data, last_slash + 1,
exec_name_end - last_slash - 1);
// Start w/ the next entry next time through
++index_of_kinfo_proc_;
// Done
return true;
}
return false;
}
bool NamedProcessIterator::IncludeEntry() {
return (executable_name_ == entry().exe_file() &&
ProcessIterator::IncludeEntry());
}
// ------------------------------------------------------------------------
// NOTE: about ProcessMetrics
//
// Getting a mach task from a pid for another process requires permissions in
// general, so there doesn't really seem to be a way to do these (and spinning
// up ps to fetch each stats seems dangerous to put in a base api for anyone to
// call). Child processes ipc their port, so return something if available,
// otherwise return 0.
//
ProcessMetrics::ProcessMetrics(ProcessHandle process,
ProcessMetrics::PortProvider* port_provider)
: process_(process),
last_time_(0),
last_system_time_(0),
port_provider_(port_provider) {
processor_count_ = SysInfo::NumberOfProcessors();
}
// static
ProcessMetrics* ProcessMetrics::CreateProcessMetrics(
ProcessHandle process,
ProcessMetrics::PortProvider* port_provider) {
return new ProcessMetrics(process, port_provider);
}
bool ProcessMetrics::GetIOCounters(IoCounters* io_counters) const {
return false;
}
static bool GetTaskInfo(mach_port_t task, task_basic_info_64* task_info_data) {
if (task == MACH_PORT_NULL)
return false;
mach_msg_type_number_t count = TASK_BASIC_INFO_64_COUNT;
kern_return_t kr = task_info(task,
TASK_BASIC_INFO_64,
reinterpret_cast<task_info_t>(task_info_data),
&count);
// Most likely cause for failure: |task| is a zombie.
return kr == KERN_SUCCESS;
}
size_t ProcessMetrics::GetPagefileUsage() const {
task_basic_info_64 task_info_data;
if (!GetTaskInfo(TaskForPid(process_), &task_info_data))
return 0;
return task_info_data.virtual_size;
}
size_t ProcessMetrics::GetPeakPagefileUsage() const {
return 0;
}
size_t ProcessMetrics::GetWorkingSetSize() const {
task_basic_info_64 task_info_data;
if (!GetTaskInfo(TaskForPid(process_), &task_info_data))
return 0;
return task_info_data.resident_size;
}
size_t ProcessMetrics::GetPeakWorkingSetSize() const {
return 0;
}
static bool GetCPUTypeForProcess(pid_t pid, cpu_type_t* cpu_type) {
size_t len = sizeof(*cpu_type);
int result = sysctlbyname("sysctl.proc_cputype",
cpu_type,
&len,
NULL,
0);
if (result != 0) {
PLOG(ERROR) << "sysctlbyname(""sysctl.proc_cputype"")";
return false;
}
return true;
}
static bool IsAddressInSharedRegion(mach_vm_address_t addr, cpu_type_t type) {
if (type == CPU_TYPE_I386)
return addr >= SHARED_REGION_BASE_I386 &&
addr < (SHARED_REGION_BASE_I386 + SHARED_REGION_SIZE_I386);
else if (type == CPU_TYPE_X86_64)
return addr >= SHARED_REGION_BASE_X86_64 &&
addr < (SHARED_REGION_BASE_X86_64 + SHARED_REGION_SIZE_X86_64);
else
return false;
}
// This is a rough approximation of the algorithm that libtop uses.
// private_bytes is the size of private resident memory.
// shared_bytes is the size of shared resident memory.
bool ProcessMetrics::GetMemoryBytes(size_t* private_bytes,
size_t* shared_bytes) {
kern_return_t kr;
size_t private_pages_count = 0;
size_t shared_pages_count = 0;
if (!private_bytes && !shared_bytes)
return true;
mach_port_t task = TaskForPid(process_);
if (task == MACH_PORT_NULL) {
LOG(ERROR) << "Invalid process";
return false;
}
cpu_type_t cpu_type;
if (!GetCPUTypeForProcess(process_, &cpu_type))
return false;
// The same region can be referenced multiple times. To avoid double counting
// we need to keep track of which regions we've already counted.
base::hash_set<int> seen_objects;
// We iterate through each VM region in the task's address map. For shared
// memory we add up all the pages that are marked as shared. Like libtop we
// try to avoid counting pages that are also referenced by other tasks. Since
// we don't have access to the VM regions of other tasks the only hint we have
// is if the address is in the shared region area.
//
// Private memory is much simpler. We simply count the pages that are marked
// as private or copy on write (COW).
//
// See libtop_update_vm_regions in
// http://www.opensource.apple.com/source/top/top-67/libtop.c
mach_vm_size_t size = 0;
for (mach_vm_address_t address = MACH_VM_MIN_ADDRESS;; address += size) {
vm_region_top_info_data_t info;
mach_msg_type_number_t info_count = VM_REGION_TOP_INFO_COUNT;
mach_port_t object_name;
kr = mach_vm_region(task,
&address,
&size,
VM_REGION_TOP_INFO,
(vm_region_info_t)&info,
&info_count,
&object_name);
if (kr == KERN_INVALID_ADDRESS) {
// We're at the end of the address space.
break;
} else if (kr != KERN_SUCCESS) {
LOG(ERROR) << "Calling mach_vm_region failed with error: "
<< mach_error_string(kr);
return false;
}
if (IsAddressInSharedRegion(address, cpu_type) &&
info.share_mode != SM_PRIVATE)
continue;
if (info.share_mode == SM_COW && info.ref_count == 1)
info.share_mode = SM_PRIVATE;
switch (info.share_mode) {
case SM_PRIVATE:
private_pages_count += info.private_pages_resident;
private_pages_count += info.shared_pages_resident;
break;
case SM_COW:
private_pages_count += info.private_pages_resident;
// Fall through
case SM_SHARED:
if (seen_objects.count(info.obj_id) == 0) {
// Only count the first reference to this region.
seen_objects.insert(info.obj_id);
shared_pages_count += info.shared_pages_resident;
}
break;
default:
break;
}
}
vm_size_t page_size;
kr = host_page_size(task, &page_size);
if (kr != KERN_SUCCESS) {
LOG(ERROR) << "Failed to fetch host page size, error: "
<< mach_error_string(kr);
return false;
}
if (private_bytes)
*private_bytes = private_pages_count * page_size;
if (shared_bytes)
*shared_bytes = shared_pages_count * page_size;
return true;
}
void ProcessMetrics::GetCommittedKBytes(CommittedKBytes* usage) const {
}
bool ProcessMetrics::GetWorkingSetKBytes(WorkingSetKBytes* ws_usage) const {
size_t priv = GetWorkingSetSize();
if (!priv)
return false;
ws_usage->priv = priv / 1024;
ws_usage->shareable = 0;
ws_usage->shared = 0;
return true;
}
#define TIME_VALUE_TO_TIMEVAL(a, r) do { \
(r)->tv_sec = (a)->seconds; \
(r)->tv_usec = (a)->microseconds; \
} while (0)
double ProcessMetrics::GetCPUUsage() {
mach_port_t task = TaskForPid(process_);
if (task == MACH_PORT_NULL)
return 0;
kern_return_t kr;
// Libtop explicitly loops over the threads (libtop_pinfo_update_cpu_usage()
// in libtop.c), but this is more concise and gives the same results:
task_thread_times_info thread_info_data;
mach_msg_type_number_t thread_info_count = TASK_THREAD_TIMES_INFO_COUNT;
kr = task_info(task,
TASK_THREAD_TIMES_INFO,
reinterpret_cast<task_info_t>(&thread_info_data),
&thread_info_count);
if (kr != KERN_SUCCESS) {
// Most likely cause: |task| is a zombie.
return 0;
}
task_basic_info_64 task_info_data;
if (!GetTaskInfo(task, &task_info_data))
return 0;
/* Set total_time. */
// thread info contains live time...
struct timeval user_timeval, system_timeval, task_timeval;
TIME_VALUE_TO_TIMEVAL(&thread_info_data.user_time, &user_timeval);
TIME_VALUE_TO_TIMEVAL(&thread_info_data.system_time, &system_timeval);
timeradd(&user_timeval, &system_timeval, &task_timeval);
// ... task info contains terminated time.
TIME_VALUE_TO_TIMEVAL(&task_info_data.user_time, &user_timeval);
TIME_VALUE_TO_TIMEVAL(&task_info_data.system_time, &system_timeval);
timeradd(&user_timeval, &task_timeval, &task_timeval);
timeradd(&system_timeval, &task_timeval, &task_timeval);
struct timeval now;
int retval = gettimeofday(&now, NULL);
if (retval)
return 0;
int64 time = TimeValToMicroseconds(now);
int64 task_time = TimeValToMicroseconds(task_timeval);
if ((last_system_time_ == 0) || (last_time_ == 0)) {
// First call, just set the last values.
last_system_time_ = task_time;
last_time_ = time;
return 0;
}
int64 system_time_delta = task_time - last_system_time_;
int64 time_delta = time - last_time_;
DCHECK(time_delta != 0);
if (time_delta == 0)
return 0;
// We add time_delta / 2 so the result is rounded.
double cpu = static_cast<double>((system_time_delta * 100.0) / time_delta);
last_system_time_ = task_time;
last_time_ = time;
return cpu;
}
mach_port_t ProcessMetrics::TaskForPid(ProcessHandle process) const {
mach_port_t task = MACH_PORT_NULL;
if (port_provider_)
task = port_provider_->TaskForPid(process_);
if (task == MACH_PORT_NULL && process_ == getpid())
task = mach_task_self();
return task;
}
// ------------------------------------------------------------------------
// Bytes committed by the system.
size_t GetSystemCommitCharge() {
host_name_port_t host = mach_host_self();
mach_msg_type_number_t count = HOST_VM_INFO_COUNT;
vm_statistics_data_t data;
kern_return_t kr = host_statistics(host, HOST_VM_INFO,
reinterpret_cast<host_info_t>(&data),
&count);
if (kr) {
LOG(WARNING) << "Failed to fetch host statistics.";
return 0;
}
vm_size_t page_size;
kr = host_page_size(host, &page_size);
if (kr) {
LOG(ERROR) << "Failed to fetch host page size.";
return 0;
}
return (data.active_count * page_size) / 1024;
}
// ------------------------------------------------------------------------
namespace {
bool g_oom_killer_enabled;
// === C malloc/calloc/valloc/realloc/posix_memalign ===
typedef void* (*malloc_type)(struct _malloc_zone_t* zone,
size_t size);
typedef void* (*calloc_type)(struct _malloc_zone_t* zone,
size_t num_items,
size_t size);
typedef void* (*valloc_type)(struct _malloc_zone_t* zone,
size_t size);
typedef void* (*realloc_type)(struct _malloc_zone_t* zone,
void* ptr,
size_t size);
typedef void* (*memalign_type)(struct _malloc_zone_t* zone,
size_t alignment,
size_t size);
malloc_type g_old_malloc;
calloc_type g_old_calloc;
valloc_type g_old_valloc;
realloc_type g_old_realloc;
memalign_type g_old_memalign;
malloc_type g_old_malloc_purgeable;
calloc_type g_old_calloc_purgeable;
valloc_type g_old_valloc_purgeable;
realloc_type g_old_realloc_purgeable;
memalign_type g_old_memalign_purgeable;
void* oom_killer_malloc(struct _malloc_zone_t* zone,
size_t size) {
void* result = g_old_malloc(zone, size);
if (!result && size)
debug::BreakDebugger();
return result;
}
void* oom_killer_calloc(struct _malloc_zone_t* zone,
size_t num_items,
size_t size) {
void* result = g_old_calloc(zone, num_items, size);
if (!result && num_items && size)
debug::BreakDebugger();
return result;
}
void* oom_killer_valloc(struct _malloc_zone_t* zone,
size_t size) {
void* result = g_old_valloc(zone, size);
if (!result && size)
debug::BreakDebugger();
return result;
}
void* oom_killer_realloc(struct _malloc_zone_t* zone,
void* ptr,
size_t size) {
void* result = g_old_realloc(zone, ptr, size);
if (!result && size)
debug::BreakDebugger();
return result;
}
void* oom_killer_memalign(struct _malloc_zone_t* zone,
size_t alignment,
size_t size) {
void* result = g_old_memalign(zone, alignment, size);
// Only die if posix_memalign would have returned ENOMEM, since there are
// other reasons why NULL might be returned (see
// http://opensource.apple.com/source/Libc/Libc-583/gen/malloc.c ).
if (!result && size && alignment >= sizeof(void*)
&& (alignment & (alignment - 1)) == 0) {
debug::BreakDebugger();
}
return result;
}
void* oom_killer_malloc_purgeable(struct _malloc_zone_t* zone,
size_t size) {
void* result = g_old_malloc_purgeable(zone, size);
if (!result && size)
debug::BreakDebugger();
return result;
}
void* oom_killer_calloc_purgeable(struct _malloc_zone_t* zone,
size_t num_items,
size_t size) {
void* result = g_old_calloc_purgeable(zone, num_items, size);
if (!result && num_items && size)
debug::BreakDebugger();
return result;
}
void* oom_killer_valloc_purgeable(struct _malloc_zone_t* zone,
size_t size) {
void* result = g_old_valloc_purgeable(zone, size);
if (!result && size)
debug::BreakDebugger();
return result;
}
void* oom_killer_realloc_purgeable(struct _malloc_zone_t* zone,
void* ptr,
size_t size) {
void* result = g_old_realloc_purgeable(zone, ptr, size);
if (!result && size)
debug::BreakDebugger();
return result;
}
void* oom_killer_memalign_purgeable(struct _malloc_zone_t* zone,
size_t alignment,
size_t size) {
void* result = g_old_memalign_purgeable(zone, alignment, size);
// Only die if posix_memalign would have returned ENOMEM, since there are
// other reasons why NULL might be returned (see
// http://opensource.apple.com/source/Libc/Libc-583/gen/malloc.c ).
if (!result && size && alignment >= sizeof(void*)
&& (alignment & (alignment - 1)) == 0) {
debug::BreakDebugger();
}
return result;
}
// === C++ operator new ===
void oom_killer_new() {
debug::BreakDebugger();
}
// === Core Foundation CFAllocators ===
bool CanGetContextForCFAllocator(long darwin_version) {
// TODO(avi): remove at final release; http://crbug.com/74589
if (darwin_version == 11) {
NSLog(@"Unsure about the internals of CFAllocator but going to patch them "
"anyway. Watch out for crashes inside of CFAllocatorAllocate.");
}
return darwin_version == 9 ||
darwin_version == 10 ||
darwin_version == 11;
}
CFAllocatorContext* ContextForCFAllocator(CFAllocatorRef allocator,
long darwin_version) {
if (darwin_version == 9 || darwin_version == 10) {
ChromeCFAllocator9and10* our_allocator =
const_cast<ChromeCFAllocator9and10*>(
reinterpret_cast<const ChromeCFAllocator9and10*>(allocator));
return &our_allocator->_context;
} else if (darwin_version == 11) {
ChromeCFAllocator11* our_allocator =
const_cast<ChromeCFAllocator11*>(
reinterpret_cast<const ChromeCFAllocator11*>(allocator));
return &our_allocator->_context;
} else {
return NULL;
}
}
CFAllocatorAllocateCallBack g_old_cfallocator_system_default;
CFAllocatorAllocateCallBack g_old_cfallocator_malloc;
CFAllocatorAllocateCallBack g_old_cfallocator_malloc_zone;
void* oom_killer_cfallocator_system_default(CFIndex alloc_size,
CFOptionFlags hint,
void* info) {
void* result = g_old_cfallocator_system_default(alloc_size, hint, info);
if (!result)
debug::BreakDebugger();
return result;
}
void* oom_killer_cfallocator_malloc(CFIndex alloc_size,
CFOptionFlags hint,
void* info) {
void* result = g_old_cfallocator_malloc(alloc_size, hint, info);
if (!result)
debug::BreakDebugger();
return result;
}
void* oom_killer_cfallocator_malloc_zone(CFIndex alloc_size,
CFOptionFlags hint,
void* info) {
void* result = g_old_cfallocator_malloc_zone(alloc_size, hint, info);
if (!result)
debug::BreakDebugger();
return result;
}
// === Cocoa NSObject allocation ===
typedef id (*allocWithZone_t)(id, SEL, NSZone*);
allocWithZone_t g_old_allocWithZone;
id oom_killer_allocWithZone(id self, SEL _cmd, NSZone* zone)
{
id result = g_old_allocWithZone(self, _cmd, zone);
if (!result)
debug::BreakDebugger();
return result;
}
} // namespace
malloc_zone_t* GetPurgeableZone() {
// malloc_default_purgeable_zone only exists on >= 10.6. Use dlsym to grab it
// at runtime because it may not be present in the SDK used for compilation.
typedef malloc_zone_t* (*malloc_default_purgeable_zone_t)(void);
malloc_default_purgeable_zone_t malloc_purgeable_zone =
reinterpret_cast<malloc_default_purgeable_zone_t>(
dlsym(RTLD_DEFAULT, "malloc_default_purgeable_zone"));
if (malloc_purgeable_zone)
return malloc_purgeable_zone();
return NULL;
}
void EnableTerminationOnOutOfMemory() {
if (g_oom_killer_enabled)
return;
g_oom_killer_enabled = true;
// Not SysInfo::OperatingSystemVersionNumbers as that calls through to Gestalt
// which ends up (on > 10.6) spawning threads.
struct utsname machine_info;
if (uname(&machine_info)) {
return;
}
// The string machine_info.release is the xnu/Darwin version number, "9.xxx"
// on Mac OS X 10.5, and "10.xxx" on Mac OS X 10.6. See
// http://en.wikipedia.org/wiki/Darwin_(operating_system) .
long darwin_version = strtol(machine_info.release, NULL, 10);
// === C malloc/calloc/valloc/realloc/posix_memalign ===
// This approach is not perfect, as requests for amounts of memory larger than
// MALLOC_ABSOLUTE_MAX_SIZE (currently SIZE_T_MAX - (2 * PAGE_SIZE)) will
// still fail with a NULL rather than dying (see
// http://opensource.apple.com/source/Libc/Libc-583/gen/malloc.c for details).
// Unfortunately, it's the best we can do. Also note that this does not affect
// allocations from non-default zones.
CHECK(!g_old_malloc && !g_old_calloc && !g_old_valloc && !g_old_realloc &&
!g_old_memalign) << "Old allocators unexpectedly non-null";
CHECK(!g_old_malloc_purgeable && !g_old_calloc_purgeable &&
!g_old_valloc_purgeable && !g_old_realloc_purgeable &&
!g_old_memalign_purgeable) << "Old allocators unexpectedly non-null";
// See http://trac.webkit.org/changeset/53362/trunk/Tools/DumpRenderTree/mac
bool zone_allocators_protected = darwin_version > 10;
ChromeMallocZone* default_zone =
reinterpret_cast<ChromeMallocZone*>(malloc_default_zone());
ChromeMallocZone* purgeable_zone =
reinterpret_cast<ChromeMallocZone*>(GetPurgeableZone());
vm_address_t page_start_default = NULL;
vm_address_t page_start_purgeable = NULL;
vm_size_t len_default = 0;
vm_size_t len_purgeable = 0;
if (zone_allocators_protected) {
page_start_default = reinterpret_cast<vm_address_t>(default_zone) &
static_cast<vm_size_t>(~(getpagesize() - 1));
len_default = reinterpret_cast<vm_address_t>(default_zone) -
page_start_default + sizeof(ChromeMallocZone);
mprotect(reinterpret_cast<void*>(page_start_default), len_default,
PROT_READ | PROT_WRITE);
if (purgeable_zone) {
page_start_purgeable = reinterpret_cast<vm_address_t>(purgeable_zone) &
static_cast<vm_size_t>(~(getpagesize() - 1));
len_purgeable = reinterpret_cast<vm_address_t>(purgeable_zone) -
page_start_purgeable + sizeof(ChromeMallocZone);
mprotect(reinterpret_cast<void*>(page_start_purgeable), len_purgeable,
PROT_READ | PROT_WRITE);
}
}
// Default zone
g_old_malloc = default_zone->malloc;
g_old_calloc = default_zone->calloc;
g_old_valloc = default_zone->valloc;
g_old_realloc = default_zone->realloc;
CHECK(g_old_malloc && g_old_calloc && g_old_valloc && g_old_realloc)
<< "Failed to get system allocation functions.";
default_zone->malloc = oom_killer_malloc;
default_zone->calloc = oom_killer_calloc;
default_zone->valloc = oom_killer_valloc;
default_zone->realloc = oom_killer_realloc;
if (default_zone->version >= 5) {
g_old_memalign = default_zone->memalign;
if (g_old_memalign)
default_zone->memalign = oom_killer_memalign;
}
// Purgeable zone (if it exists)
if (purgeable_zone) {
g_old_malloc_purgeable = purgeable_zone->malloc;
g_old_calloc_purgeable = purgeable_zone->calloc;
g_old_valloc_purgeable = purgeable_zone->valloc;
g_old_realloc_purgeable = purgeable_zone->realloc;
CHECK(g_old_malloc_purgeable && g_old_calloc_purgeable &&
g_old_valloc_purgeable && g_old_realloc_purgeable)
<< "Failed to get system allocation functions.";
purgeable_zone->malloc = oom_killer_malloc_purgeable;
purgeable_zone->calloc = oom_killer_calloc_purgeable;
purgeable_zone->valloc = oom_killer_valloc_purgeable;
purgeable_zone->realloc = oom_killer_realloc_purgeable;
if (purgeable_zone->version >= 5) {
g_old_memalign_purgeable = purgeable_zone->memalign;
if (g_old_memalign_purgeable)
purgeable_zone->memalign = oom_killer_memalign_purgeable;
}
}
if (zone_allocators_protected) {
mprotect(reinterpret_cast<void*>(page_start_default), len_default,
PROT_READ);
if (purgeable_zone) {
mprotect(reinterpret_cast<void*>(page_start_purgeable), len_purgeable,
PROT_READ);
}
}
// === C malloc_zone_batch_malloc ===
// batch_malloc is omitted because the default malloc zone's implementation
// only supports batch_malloc for "tiny" allocations from the free list. It
// will fail for allocations larger than "tiny", and will only allocate as
// many blocks as it's able to from the free list. These factors mean that it
// can return less than the requested memory even in a non-out-of-memory
// situation. There's no good way to detect whether a batch_malloc failure is
// due to these other factors, or due to genuine memory or address space
// exhaustion. The fact that it only allocates space from the "tiny" free list
// means that it's likely that a failure will not be due to memory exhaustion.
// Similarly, these constraints on batch_malloc mean that callers must always
// be expecting to receive less memory than was requested, even in situations
// where memory pressure is not a concern. Finally, the only public interface
// to batch_malloc is malloc_zone_batch_malloc, which is specific to the
// system's malloc implementation. It's unlikely that anyone's even heard of
// it.
// === C++ operator new ===
// Yes, operator new does call through to malloc, but this will catch failures
// that our imperfect handling of malloc cannot.
std::set_new_handler(oom_killer_new);
// === Core Foundation CFAllocators ===
// This will not catch allocation done by custom allocators, but will catch
// all allocation done by system-provided ones.
CHECK(!g_old_cfallocator_system_default && !g_old_cfallocator_malloc &&
!g_old_cfallocator_malloc_zone)
<< "Old allocators unexpectedly non-null";
bool cf_allocator_internals_known =
CanGetContextForCFAllocator(darwin_version);
if (cf_allocator_internals_known) {
CFAllocatorContext* context =
ContextForCFAllocator(kCFAllocatorSystemDefault, darwin_version);
CHECK(context) << "Failed to get context for kCFAllocatorSystemDefault.";
g_old_cfallocator_system_default = context->allocate;
CHECK(g_old_cfallocator_system_default)
<< "Failed to get kCFAllocatorSystemDefault allocation function.";
context->allocate = oom_killer_cfallocator_system_default;
context = ContextForCFAllocator(kCFAllocatorMalloc, darwin_version);
CHECK(context) << "Failed to get context for kCFAllocatorMalloc.";
g_old_cfallocator_malloc = context->allocate;
CHECK(g_old_cfallocator_malloc)
<< "Failed to get kCFAllocatorMalloc allocation function.";
context->allocate = oom_killer_cfallocator_malloc;
context = ContextForCFAllocator(kCFAllocatorMallocZone, darwin_version);
CHECK(context) << "Failed to get context for kCFAllocatorMallocZone.";
g_old_cfallocator_malloc_zone = context->allocate;
CHECK(g_old_cfallocator_malloc_zone)
<< "Failed to get kCFAllocatorMallocZone allocation function.";
context->allocate = oom_killer_cfallocator_malloc_zone;
} else {
NSLog(@"Internals of CFAllocator not known; out-of-memory failures via "
"CFAllocator will not result in termination. http://crbug.com/45650");
}
// === Cocoa NSObject allocation ===
// Note that both +[NSObject new] and +[NSObject alloc] call through to
// +[NSObject allocWithZone:].
CHECK(!g_old_allocWithZone)
<< "Old allocator unexpectedly non-null";
Class nsobject_class = [NSObject class];
Method orig_method = class_getClassMethod(nsobject_class,
@selector(allocWithZone:));
g_old_allocWithZone = reinterpret_cast<allocWithZone_t>(
method_getImplementation(orig_method));
CHECK(g_old_allocWithZone)
<< "Failed to get allocWithZone allocation function.";
method_setImplementation(orig_method,
reinterpret_cast<IMP>(oom_killer_allocWithZone));
}
ProcessId GetParentProcessId(ProcessHandle process) {
struct kinfo_proc info;
size_t length = sizeof(struct kinfo_proc);
int mib[4] = { CTL_KERN, KERN_PROC, KERN_PROC_PID, process };
if (sysctl(mib, 4, &info, &length, NULL, 0) < 0) {
PLOG(ERROR) << "sysctl";
return -1;
}
if (length == 0)
return -1;
return info.kp_eproc.e_ppid;
}
} // namespace base