void jl_throw_in_thread(int tid, mach_port_t thread, jl_value_t *exception)
{
unsigned int count = MACHINE_THREAD_STATE_COUNT;
x86_thread_state64_t state;
kern_return_t ret = thread_get_state(thread, x86_THREAD_STATE64, (thread_state_t)&state, &count);
HANDLE_MACH_ERROR("thread_get_state", ret);
jl_all_task_states[tid].ptls->bt_size =
rec_backtrace_ctx(jl_all_task_states[tid].ptls->bt_data,
JL_MAX_BT_SIZE, (bt_context_t)&state);
jl_all_task_states[tid].ptls->exception_in_transit = exception;
uint64_t rsp = (uint64_t)jl_all_task_states[tid].signal_stack + sig_stack_size;
rsp &= -16; // ensure 16-byte alignment
// push (null) $RIP onto the stack
rsp -= sizeof(void*);
*(void**)rsp = NULL;
state.__rsp = rsp; // set stack pointer
state.__rip = (uint64_t)&jl_rethrow; // "call" the function
ret = thread_set_state(thread, x86_THREAD_STATE64, (thread_state_t)&state, count);
HANDLE_MACH_ERROR("thread_set_state",ret);
}
DLLEXPORT int jl_profile_start_timer(void)
{
kern_return_t ret;
if (!profile_started) {
mach_port_t self = mach_task_self();
ret = host_get_clock_service(mach_host_self(), SYSTEM_CLOCK, (clock_serv_t *)&clk);
HANDLE_MACH_ERROR("host_get_clock_service", ret);
ret = mach_port_allocate(self, MACH_PORT_RIGHT_RECEIVE, &profile_port);
HANDLE_MACH_ERROR("mach_port_allocate", ret);
// Alright, create a thread to serve as the listener for exceptions
pthread_attr_t attr;
if (pthread_attr_init(&attr) != 0) {
jl_error("pthread_attr_init failed");
}
pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
if (pthread_create(&profiler_thread, &attr, mach_profile_listener, NULL) != 0) {
jl_error("pthread_create failed");
}
pthread_attr_destroy(&attr);
profile_started = 1;
}
timerprof.tv_sec = nsecprof/GIGA;
timerprof.tv_nsec = nsecprof%GIGA;
running = 1;
ret = clock_alarm(clk, TIME_RELATIVE, timerprof, profile_port);
HANDLE_MACH_ERROR("clock_alarm", ret);
return 0;
}
//exc_server uses dlsym to find symbol
DLLEXPORT
kern_return_t catch_exception_raise(mach_port_t exception_port,
mach_port_t thread,
mach_port_t task,
exception_type_t exception,
exception_data_t code,
mach_msg_type_number_t code_count)
{
unsigned int count = MACHINE_THREAD_STATE_COUNT;
unsigned int exc_count = X86_EXCEPTION_STATE64_COUNT;
x86_exception_state64_t exc_state;
x86_thread_state64_t state;
#ifdef LIBOSXUNWIND
if (thread == mach_profiler_thread) {
return profiler_segv_handler(exception_port, thread, task, exception, code, code_count);
}
#endif
kern_return_t ret = thread_get_state(thread, x86_EXCEPTION_STATE64, (thread_state_t)&exc_state, &exc_count);
HANDLE_MACH_ERROR("thread_get_state", ret);
uint64_t fault_addr = exc_state.__faultvaddr;
#ifdef SEGV_EXCEPTION
if (1) {
#else
if (msync((void*)(fault_addr & ~(jl_page_size - 1)), 1, MS_ASYNC) == 0) { // check if this was a valid address
#endif
jl_value_t *excpt;
if (is_addr_on_stack((void*)fault_addr)) {
excpt = jl_stackovf_exception;
}
#ifdef SEGV_EXCEPTION
else if (msync((void*)(fault_addr & ~(jl_page_size - 1)), 1, MS_ASYNC) != 0) {
// no page mapped at this address
excpt = jl_segv_exception;
}
#endif
else {
if (!(exc_state.__err & WRITE_FAULT))
return KERN_INVALID_ARGUMENT; // rethrow the SEGV since it wasn't an error with writing to read-only memory
excpt = jl_readonlymemory_exception;
}
jl_throw_in_thread(0, thread, excpt);
return KERN_SUCCESS;
}
else {
kern_return_t ret = thread_get_state(thread, x86_THREAD_STATE64, (thread_state_t)&state, &count);
HANDLE_MACH_ERROR("thread_get_state", ret);
jl_critical_error(SIGSEGV, (unw_context_t*)&state,
jl_bt_data, &jl_bt_size);
return KERN_INVALID_ARGUMENT;
}
}
void attach_exception_port()
{
kern_return_t ret;
// http://www.opensource.apple.com/source/xnu/xnu-2782.1.97/osfmk/man/thread_set_exception_ports.html
ret = thread_set_exception_ports(mach_thread_self(), EXC_MASK_BAD_ACCESS, segv_port, EXCEPTION_DEFAULT, MACHINE_THREAD_STATE);
HANDLE_MACH_ERROR("thread_set_exception_ports", ret);
}
static void allocate_segv_handler()
{
#ifdef JULIA_ENABLE_THREADING
arraylist_new(&suspended_threads, jl_n_threads);
#endif
pthread_t thread;
pthread_attr_t attr;
kern_return_t ret;
mach_port_t self = mach_task_self();
ret = mach_port_allocate(self, MACH_PORT_RIGHT_RECEIVE, &segv_port);
HANDLE_MACH_ERROR("mach_port_allocate",ret);
ret = mach_port_insert_right(self, segv_port, segv_port, MACH_MSG_TYPE_MAKE_SEND);
HANDLE_MACH_ERROR("mach_port_insert_right",ret);
// Alright, create a thread to serve as the listener for exceptions
if (pthread_attr_init(&attr) != 0) {
jl_error("pthread_attr_init failed");
}
pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
if (pthread_create(&thread, &attr, mach_segv_listener, NULL) != 0) {
jl_error("pthread_create failed");
}
pthread_attr_destroy(&attr);
for (int16_t tid = 0;tid < jl_n_threads;tid++) {
attach_exception_port(pthread_mach_thread_np(jl_all_task_states[tid].system_id));
}
}
//exc_server uses dlsym to find symbol
DLLEXPORT kern_return_t catch_exception_raise
(mach_port_t exception_port,
mach_port_t thread,
mach_port_t task,
exception_type_t exception,
exception_data_t code,
mach_msg_type_number_t code_count)
{
unsigned int count = MACHINE_THREAD_STATE_COUNT;
unsigned int exc_count = X86_EXCEPTION_STATE64_COUNT;
x86_thread_state64_t state, old_state;
x86_exception_state64_t exc_state;
kern_return_t ret;
//memset(&state,0,sizeof(x86_thread_state64_t));
//memset(&exc_state,0,sizeof(x86_exception_state64_t));
ret = thread_get_state(thread,x86_EXCEPTION_STATE64,(thread_state_t)&exc_state,&exc_count);
uint64_t fault_addr = exc_state.__faultvaddr;
if (
#ifdef COPY_STACKS
(char*)fault_addr > (char*)jl_stack_lo-3000000 &&
(char*)fault_addr < (char*)jl_stack_hi
#else
(char*)fault_addr > (char*)jl_current_task->stack-8192 &&
(char*)fault_addr <
(char*)jl_current_task->stack+jl_current_task->ssize
#endif
)
{
ret = thread_get_state(thread,x86_THREAD_STATE64,(thread_state_t)&state,&count);
HANDLE_MACH_ERROR("thread_get_state",ret);
old_state = state;
// memset(&state,0,sizeof(x86_thread_state64_t));
// Setup libunwind information
state.__rsp = (uint64_t)signal_stack + SIGSTKSZ;
state.__rsp -= sizeof(unw_context_t);
state.__rsp &= -16;
unw_context_t *uc = (unw_context_t*)state.__rsp;
state.__rsp -= 512;
// This is for alignment. In particular note that the sizeof(void*) is necessary
// since it would usually specify the return address (i.e. we are aligning the call
// frame to a 16 byte boundary as required by the abi, but the stack pointer
// to point to the byte beyond that. Not doing this leads to funny behavior on
// the first access to an external function will fail due to stack misalignment
state.__rsp &= -16;
state.__rsp -= sizeof(void*);
memset(uc,0,sizeof(unw_context_t));
memcpy(uc,&old_state,sizeof(x86_thread_state64_t));
state.__rdi = (uint64_t)uc;
state.__rip = (uint64_t)darwin_stack_overflow_handler;
state.__rbp = state.__rsp;
ret = thread_set_state(thread,x86_THREAD_STATE64,(thread_state_t)&state,count);
HANDLE_MACH_ERROR("thread_set_state",ret);
return KERN_SUCCESS;
}
else {
return -309;
}
}
static void allocate_segv_handler()
{
pthread_t thread;
pthread_attr_t attr;
kern_return_t ret;
mach_port_t self = mach_task_self();
ret = mach_port_allocate(self, MACH_PORT_RIGHT_RECEIVE, &segv_port);
HANDLE_MACH_ERROR("mach_port_allocate",ret);
ret = mach_port_insert_right(self, segv_port, segv_port, MACH_MSG_TYPE_MAKE_SEND);
HANDLE_MACH_ERROR("mach_port_insert_right",ret);
// Alright, create a thread to serve as the listener for exceptions
if (pthread_attr_init(&attr) != 0) {
jl_error("pthread_attr_init failed");
}
pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
if (pthread_create(&thread, &attr, mach_segv_listener, NULL) != 0) {
jl_error("pthread_create failed");
}
pthread_attr_destroy(&attr);
attach_exception_port();
}
static void jl_thread_suspend_and_get_state(int tid, unw_context_t **ctx, int sig)
{
(void)sig;
mach_port_t tid_port = pthread_mach_thread_np(jl_all_task_states[tid].system_id);
kern_return_t ret = thread_suspend(tid_port);
HANDLE_MACH_ERROR("thread_suspend", ret);
// Do the actual sampling
unsigned int count = MACHINE_THREAD_STATE_COUNT;
static unw_context_t state;
memset(&state, 0, sizeof(unw_context_t));
// Get the state of the suspended thread
ret = thread_get_state(tid_port, x86_THREAD_STATE64, (thread_state_t)&state, &count);
// Initialize the unwind context with the suspend thread's state
*ctx = &state;
}
kern_return_t profiler_segv_handler
(mach_port_t exception_port,
mach_port_t thread,
mach_port_t task,
exception_type_t exception,
exception_data_t code,
mach_msg_type_number_t code_count)
{
assert(thread == mach_profiler_thread);
x86_thread_state64_t state;
// Not currently unwinding. Raise regular segfault
if (forceDwarf == -2)
return KERN_INVALID_ARGUMENT;
if (forceDwarf == 0)
forceDwarf = 1;
else
forceDwarf = -1;
unsigned int count = MACHINE_THREAD_STATE_COUNT;
thread_get_state(thread,x86_THREAD_STATE64,(thread_state_t)&state,&count);
// don't change cs fs gs rflags
uint64_t cs = state.__cs;
uint64_t fs = state.__fs;
uint64_t gs = state.__gs;
uint64_t rflags = state.__rflags;
memcpy(&state,&profiler_uc,sizeof(x86_thread_state64_t));
state.__cs = cs;
state.__fs = fs;
state.__gs = gs;
state.__rflags = rflags;
kern_return_t ret = thread_set_state(thread,x86_THREAD_STATE64,(thread_state_t)&state,count);
HANDLE_MACH_ERROR("thread_set_state",ret);
return KERN_SUCCESS;
}
void *mach_profile_listener(void *arg)
{
(void)arg;
int max_size = 512;
mach_profiler_thread = mach_thread_self();
mig_reply_error_t *bufRequest = (mig_reply_error_t *) malloc(max_size);
while (1) {
kern_return_t ret = mach_msg(&bufRequest->Head, MACH_RCV_MSG,
0, max_size, profile_port,
MACH_MSG_TIMEOUT_NONE, MACH_PORT_NULL);
HANDLE_MACH_ERROR("mach_msg",ret);
if (bt_size_cur < bt_size_max) {
kern_return_t ret;
// Suspend the thread so we may safely sample it
ret = thread_suspend(main_thread);
HANDLE_MACH_ERROR("thread_suspend",ret);
// Do the actual sampling
unsigned int count = MACHINE_THREAD_STATE_COUNT;
x86_thread_state64_t state;
// Get the state of the suspended thread
ret = thread_get_state(main_thread,x86_THREAD_STATE64,(thread_state_t)&state,&count);
HANDLE_MACH_ERROR("thread_get_state",ret);
// Initialize the unwind context with the suspend thread's state
unw_context_t uc;
memset(&uc,0,sizeof(unw_context_t));
memcpy(&uc,&state,sizeof(x86_thread_state64_t));
/*
* Unfortunately compact unwind info is incorrectly generated for quite a number of
* libraries by quite a large number of compilers. We can fall back to DWARF unwind info
* in some cases, but in quite a number of cases (especially libraries not compiled in debug
* mode, only the compact unwind info may be available). Even more unfortunately, there is no
* way to detect such bogus compact unwind info (other than noticing the resulting segfault).
* What we do here is ugly, but necessary until the compact unwind info situation improves.
* We try to use the compact unwind info and if that results in a segfault, we retry with DWARF info.
* Note that in a small number of cases this may result in bogus stack traces, but at least the topmost
* entry will always be correct, and the number of cases in which this is an issue is rather small.
* Other than that, this implementation is not incorrect as the other thread is paused while we are profiling
* and during stack unwinding we only ever read memory, but never write it.
*/
forceDwarf = 0;
unw_getcontext(&profiler_uc);
if (forceDwarf == 0) {
// Save the backtrace
bt_size_cur += rec_backtrace_ctx((ptrint_t*)bt_data_prof+bt_size_cur, bt_size_max-bt_size_cur-1, &uc);
}
else if (forceDwarf == 1) {
bt_size_cur += rec_backtrace_ctx_dwarf((ptrint_t*)bt_data_prof+bt_size_cur, bt_size_max-bt_size_cur-1, &uc);
}
else if (forceDwarf == -1) {
JL_PRINTF(JL_STDERR, "Warning: Profiler attempt to access an invalid memory location\n");
}
forceDwarf = -2;
// Mark the end of this block with 0
bt_data_prof[bt_size_cur] = 0;
bt_size_cur++;
// We're done! Resume the thread.
ret = thread_resume(main_thread);
HANDLE_MACH_ERROR("thread_resume",ret)
if (running) {
// Reset the alarm
ret = clock_alarm(clk, TIME_RELATIVE, timerprof, profile_port);
HANDLE_MACH_ERROR("clock_alarm",ret)
}
}
}
//exc_server uses dlsym to find symbol
DLLEXPORT
kern_return_t catch_exception_raise(mach_port_t exception_port,
mach_port_t thread,
mach_port_t task,
exception_type_t exception,
exception_data_t code,
mach_msg_type_number_t code_count)
{
unsigned int count = MACHINE_THREAD_STATE_COUNT;
unsigned int exc_count = X86_EXCEPTION_STATE64_COUNT;
x86_thread_state64_t state, old_state;
x86_exception_state64_t exc_state;
kern_return_t ret;
//memset(&state,0,sizeof(x86_thread_state64_t));
//memset(&exc_state,0,sizeof(x86_exception_state64_t));
#ifdef LIBOSXUNWIND
if (thread == mach_profiler_thread) {
return profiler_segv_handler(exception_port,thread,task,exception,code,code_count);
}
#endif
ret = thread_get_state(thread,x86_EXCEPTION_STATE64,(thread_state_t)&exc_state,&exc_count);
HANDLE_MACH_ERROR("thread_get_state(1)",ret);
uint64_t fault_addr = exc_state.__faultvaddr;
#ifdef SEGV_EXCEPTION
if (1) {
#else
if (msync((void*)(fault_addr & ~(jl_page_size - 1)), 1, MS_ASYNC) == 0) { // check if this was a valid address
#endif
ret = thread_get_state(thread,x86_THREAD_STATE64,(thread_state_t)&state,&count);
HANDLE_MACH_ERROR("thread_get_state(2)",ret);
old_state = state;
// memset(&state,0,sizeof(x86_thread_state64_t));
// Setup libunwind information
state.__rsp = (uint64_t)signal_stack + sig_stack_size;
state.__rsp -= sizeof(unw_context_t);
state.__rsp &= -16;
unw_context_t *uc = (unw_context_t*)state.__rsp;
state.__rsp -= 512;
// This is for alignment. In particular note that the sizeof(void*) is necessary
// since it would usually specify the return address (i.e., we are aligning the call
// frame to a 16 byte boundary as required by the abi, but the stack pointer
// to point to the byte beyond that. Not doing this leads to funny behavior on
// the first access to an external function will fail due to stack misalignment
state.__rsp &= -16;
state.__rsp -= sizeof(void*);
memset(uc,0,sizeof(unw_context_t));
memcpy(uc,&old_state,sizeof(x86_thread_state64_t));
state.__rdi = (uint64_t)uc;
if (is_addr_on_stack((void*)fault_addr)) {
state.__rip = (uint64_t)darwin_stack_overflow_handler;
}
#ifdef SEGV_EXCEPTION
else if (msync((void*)(fault_addr & ~(jl_page_size - 1)), 1, MS_ASYNC) != 0) {
// no page mapped at this address
state.__rip = (uint64_t)darwin_segv_handler;
}
#endif
else {
if (!(exc_state.__err & WRITE_FAULT))
return KERN_INVALID_ARGUMENT; // rethrow the SEGV since it wasn't an error with writing to read-only memory
state.__rip = (uint64_t)darwin_accerr_handler;
}
state.__rbp = state.__rsp;
ret = thread_set_state(thread,x86_THREAD_STATE64,(thread_state_t)&state,count);
HANDLE_MACH_ERROR("thread_set_state",ret);
return KERN_SUCCESS;
}
else {
ret = thread_get_state(thread,x86_THREAD_STATE64,(thread_state_t)&state,&count);
HANDLE_MACH_ERROR("thread_get_state(3)",ret);
jl_safe_printf("\nsignal (%d): %s\n", SIGSEGV, strsignal(SIGSEGV));
bt_size = rec_backtrace_ctx(bt_data, MAX_BT_SIZE, (unw_context_t*)&state);
jlbacktrace();
return KERN_INVALID_ARGUMENT;
}
}
void attach_exception_port()
{
kern_return_t ret;
// http://www.opensource.apple.com/source/xnu/xnu-2782.1.97/osfmk/man/thread_set_exception_ports.html
ret = thread_set_exception_ports(mach_thread_self(),EXC_MASK_BAD_ACCESS,segv_port,EXCEPTION_DEFAULT,MACHINE_THREAD_STATE);
HANDLE_MACH_ERROR("thread_set_exception_ports",ret);
}
void julia_init(char *imageFile)
{
jl_page_size = jl_getpagesize();
jl_find_stack_bottom();
jl_dl_handle = jl_load_dynamic_library(NULL, JL_RTLD_DEFAULT);
#ifdef _OS_WINDOWS_
uv_dlopen("ntdll.dll",jl_ntdll_handle); //bypass julia's pathchecking for system dlls
uv_dlopen("Kernel32.dll",jl_kernel32_handle);
uv_dlopen("msvcrt.dll",jl_crtdll_handle);
uv_dlopen("Ws2_32.dll",jl_winsock_handle);
_jl_exe_handle.handle = GetModuleHandleA(NULL);
if (!DuplicateHandle( GetCurrentProcess(), GetCurrentThread(),
GetCurrentProcess(), (PHANDLE)&hMainThread, 0,
TRUE, DUPLICATE_SAME_ACCESS )) {
JL_PRINTF(JL_STDERR, "Couldn't access handle to main thread\n");
}
#if defined(_CPU_X86_64_)
SymSetOptions(SYMOPT_UNDNAME | SYMOPT_DEFERRED_LOADS);
SymInitialize(GetCurrentProcess(), NULL, 1);
needsSymRefreshModuleList = 0;
#endif
#endif
jl_io_loop = uv_default_loop(); //this loop will internal events (spawining process etc.)
init_stdio();
#if defined(__linux__)
int ncores = jl_cpu_cores();
if (ncores > 1) {
cpu_set_t cpumask;
CPU_ZERO(&cpumask);
for(int i=0; i < ncores; i++) {
CPU_SET(i, &cpumask);
}
sched_setaffinity(0, sizeof(cpu_set_t), &cpumask);
}
#endif
#ifdef JL_GC_MARKSWEEP
jl_gc_init();
jl_gc_disable();
#endif
jl_init_frontend();
jl_init_types();
jl_init_tasks(jl_stack_lo, jl_stack_hi-jl_stack_lo);
jl_init_codegen();
jl_an_empty_cell = (jl_value_t*)jl_alloc_cell_1d(0);
jl_init_serializer();
if (!imageFile) {
jl_main_module = jl_new_module(jl_symbol("Main"));
jl_main_module->parent = jl_main_module;
jl_core_module = jl_new_module(jl_symbol("Core"));
jl_core_module->parent = jl_main_module;
jl_set_const(jl_main_module, jl_symbol("Core"),
(jl_value_t*)jl_core_module);
jl_module_using(jl_main_module, jl_core_module);
jl_current_module = jl_core_module;
jl_init_intrinsic_functions();
jl_init_primitives();
jl_load("boot.jl");
jl_get_builtin_hooks();
jl_boot_file_loaded = 1;
jl_init_box_caches();
}
if (imageFile) {
JL_TRY {
jl_restore_system_image(imageFile);
}
JL_CATCH {
JL_PRINTF(JL_STDERR, "error during init:\n");
jl_show(jl_stderr_obj(), jl_exception_in_transit);
JL_PRINTF(JL_STDERR, "\n");
jl_exit(1);
}
}
// set module field of primitive types
int i;
void **table = jl_core_module->bindings.table;
for(i=1; i < jl_core_module->bindings.size; i+=2) {
if (table[i] != HT_NOTFOUND) {
jl_binding_t *b = (jl_binding_t*)table[i];
if (b->value && jl_is_datatype(b->value)) {
jl_datatype_t *tt = (jl_datatype_t*)b->value;
tt->name->module = jl_core_module;
}
}
}
// the Main module is the one which is always open, and set as the
// current module for bare (non-module-wrapped) toplevel expressions.
// it does "using Base" if Base is available.
if (jl_base_module != NULL) {
jl_add_standard_imports(jl_main_module);
}
// eval() uses Main by default, so Main.eval === Core.eval
jl_module_import(jl_main_module, jl_core_module, jl_symbol("eval"));
jl_current_module = jl_main_module;
#ifndef _OS_WINDOWS_
signal_stack = malloc(SIGSTKSZ);
struct sigaction actf;
memset(&actf, 0, sizeof(struct sigaction));
sigemptyset(&actf.sa_mask);
actf.sa_handler = fpe_handler;
actf.sa_flags = 0;
if (sigaction(SIGFPE, &actf, NULL) < 0) {
JL_PRINTF(JL_STDERR, "sigaction: %s\n", strerror(errno));
jl_exit(1);
}
#if defined(_OS_LINUX_)
stack_t ss;
ss.ss_flags = 0;
ss.ss_size = SIGSTKSZ;
ss.ss_sp = signal_stack;
if (sigaltstack(&ss, NULL) < 0) {
JL_PRINTF(JL_STDERR, "sigaltstack: %s\n", strerror(errno));
jl_exit(1);
}
struct sigaction act;
memset(&act, 0, sizeof(struct sigaction));
sigemptyset(&act.sa_mask);
act.sa_sigaction = segv_handler;
act.sa_flags = SA_ONSTACK | SA_SIGINFO;
if (sigaction(SIGSEGV, &act, NULL) < 0) {
JL_PRINTF(JL_STDERR, "sigaction: %s\n", strerror(errno));
jl_exit(1);
}
if (signal(SIGPIPE,SIG_IGN) == SIG_ERR) {
JL_PRINTF(JL_STDERR, "Couldn't set SIGPIPE\n");
jl_exit(1);
}
#elif defined (_OS_DARWIN_)
kern_return_t ret;
mach_port_t self = mach_task_self();
ret = mach_port_allocate(self,MACH_PORT_RIGHT_RECEIVE,&segv_port);
HANDLE_MACH_ERROR("mach_port_allocate",ret);
ret = mach_port_insert_right(self,segv_port,segv_port,MACH_MSG_TYPE_MAKE_SEND);
HANDLE_MACH_ERROR("mach_port_insert_right",ret);
// Alright, create a thread to serve as the listener for exceptions
pthread_t thread;
pthread_attr_t attr;
if (pthread_attr_init(&attr) != 0)
{
JL_PRINTF(JL_STDERR, "pthread_attr_init failed");
jl_exit(1);
}
pthread_attr_setdetachstate(&attr,PTHREAD_CREATE_DETACHED);
if (pthread_create(&thread,&attr,mach_segv_listener,NULL) != 0)
{
JL_PRINTF(JL_STDERR, "pthread_create failed");
jl_exit(1);
}
pthread_attr_destroy(&attr);
ret = task_set_exception_ports(self,EXC_MASK_BAD_ACCESS,segv_port,EXCEPTION_DEFAULT,MACHINE_THREAD_STATE);
HANDLE_MACH_ERROR("task_set_exception_ports",ret);
#endif
#else
if (signal(SIGFPE, (void (__cdecl *)(int))fpe_handler) == SIG_ERR) {
JL_PRINTF(JL_STDERR, "Couldn't set SIGFPE\n");
jl_exit(1);
}
#endif
#ifdef JL_GC_MARKSWEEP
jl_gc_enable();
#endif
}
void *mach_profile_listener(void *arg)
{
(void)arg;
int i;
const int max_size = 512;
attach_exception_port();
#ifdef LIBOSXUNWIND
mach_profiler_thread = mach_thread_self();
#endif
mig_reply_error_t *bufRequest = (mig_reply_error_t *) malloc(max_size);
while (1) {
kern_return_t ret = mach_msg(&bufRequest->Head, MACH_RCV_MSG,
0, max_size, profile_port,
MACH_MSG_TIMEOUT_NONE, MACH_PORT_NULL);
HANDLE_MACH_ERROR("mach_msg", ret);
// sample each thread, round-robin style in reverse order
// (so that thread zero gets notified last)
for (i = jl_n_threads; i-- > 0; ) {
// if there is no space left, break early
if (bt_size_cur >= bt_size_max - 1)
break;
unw_context_t *uc;
jl_thread_suspend_and_get_state(i, &uc, -1);
#ifdef LIBOSXUNWIND
/*
* Unfortunately compact unwind info is incorrectly generated for quite a number of
* libraries by quite a large number of compilers. We can fall back to DWARF unwind info
* in some cases, but in quite a number of cases (especially libraries not compiled in debug
* mode, only the compact unwind info may be available). Even more unfortunately, there is no
* way to detect such bogus compact unwind info (other than noticing the resulting segfault).
* What we do here is ugly, but necessary until the compact unwind info situation improves.
* We try to use the compact unwind info and if that results in a segfault, we retry with DWARF info.
* Note that in a small number of cases this may result in bogus stack traces, but at least the topmost
* entry will always be correct, and the number of cases in which this is an issue is rather small.
* Other than that, this implementation is not incorrect as the other thread is paused while we are profiling
* and during stack unwinding we only ever read memory, but never write it.
*/
forceDwarf = 0;
unw_getcontext(&profiler_uc); // will resume from this point if the next lines segfault at any point
if (forceDwarf == 0) {
// Save the backtrace
bt_size_cur += rec_backtrace_ctx((ptrint_t*)bt_data_prof + bt_size_cur, bt_size_max - bt_size_cur - 1, uc);
}
else if (forceDwarf == 1) {
bt_size_cur += rec_backtrace_ctx_dwarf((ptrint_t*)bt_data_prof + bt_size_cur, bt_size_max - bt_size_cur - 1, uc);
}
else if (forceDwarf == -1) {
jl_safe_printf("WARNING: profiler attempt to access an invalid memory location\n");
}
forceDwarf = -2;
#else
bt_size_cur += rec_backtrace_ctx((ptrint_t*)bt_data_prof + bt_size_cur, bt_size_max - bt_size_cur - 1, uc);
#endif
// Mark the end of this block with 0
bt_data_prof[bt_size_cur++] = 0;
// We're done! Resume the thread.
jl_thread_resume(i, 0);
if (running) {
// Reset the alarm
kern_return_t ret = clock_alarm(clk, TIME_RELATIVE, timerprof, profile_port);
HANDLE_MACH_ERROR("clock_alarm", ret)
}
}
}
}
//exc_server uses dlsym to find symbol
JL_DLLEXPORT
kern_return_t catch_exception_raise(mach_port_t exception_port,
mach_port_t thread,
mach_port_t task,
exception_type_t exception,
exception_data_t code,
mach_msg_type_number_t code_count)
{
unsigned int count = MACHINE_THREAD_STATE_COUNT;
unsigned int exc_count = X86_EXCEPTION_STATE64_COUNT;
x86_exception_state64_t exc_state;
x86_thread_state64_t state;
#ifdef LIBOSXUNWIND
if (thread == mach_profiler_thread) {
return profiler_segv_handler(exception_port, thread, task, exception, code, code_count);
}
#endif
int16_t tid;
#ifdef JULIA_ENABLE_THREADING
jl_tls_states_t *ptls = NULL;
for (tid = 0;tid < jl_n_threads;tid++) {
if (pthread_mach_thread_np(jl_all_task_states[tid].system_id) == thread) {
ptls = jl_all_task_states[tid].ptls;
break;
}
}
if (!ptls) {
// We don't know about this thread, let the kernel try another handler
// instead. This shouldn't actually happen since we only register the
// handler for the threads we know about.
jl_safe_printf("ERROR: Exception handler triggered on unmanaged thread.\n");
return KERN_INVALID_ARGUMENT;
}
#else
jl_tls_states_t *ptls = &jl_tls_states;
tid = 0;
#endif
kern_return_t ret = thread_get_state(thread, x86_EXCEPTION_STATE64, (thread_state_t)&exc_state, &exc_count);
HANDLE_MACH_ERROR("thread_get_state", ret);
uint64_t fault_addr = exc_state.__faultvaddr;
#ifdef JULIA_ENABLE_THREADING
if (fault_addr == (uintptr_t)jl_gc_signal_page) {
JL_LOCK_NOGC(gc_suspend);
if (!jl_gc_safepoint_activated) {
// GC is done before we get the message, do nothing and return
JL_UNLOCK_NOGC(gc_suspend);
return KERN_SUCCESS;
}
// Otherwise, set the gc state of the thread, suspend and record it
int8_t gc_state = ptls->gc_state;
ptls->gc_state = JL_GC_STATE_WAITING;
uintptr_t item = tid | (((uintptr_t)gc_state) << 16);
arraylist_push(&suspended_threads, (void*)item);
thread_suspend(thread);
JL_UNLOCK_NOGC(gc_suspend);
return KERN_SUCCESS;
}
#endif
#ifdef SEGV_EXCEPTION
if (1) {
#else
if (msync((void*)(fault_addr & ~(jl_page_size - 1)), 1, MS_ASYNC) == 0) { // check if this was a valid address
#endif
jl_value_t *excpt;
if (is_addr_on_stack(ptls, (void*)fault_addr)) {
excpt = jl_stackovf_exception;
}
#ifdef SEGV_EXCEPTION
else if (msync((void*)(fault_addr & ~(jl_page_size - 1)), 1, MS_ASYNC) != 0) {
// no page mapped at this address
excpt = jl_segv_exception;
}
#endif
else {
if (!(exc_state.__err & WRITE_FAULT))
return KERN_INVALID_ARGUMENT; // rethrow the SEGV since it wasn't an error with writing to read-only memory
excpt = jl_readonlymemory_exception;
}
jl_throw_in_thread(tid, thread, excpt);
return KERN_SUCCESS;
}
else {
kern_return_t ret = thread_get_state(thread, x86_THREAD_STATE64, (thread_state_t)&state, &count);
HANDLE_MACH_ERROR("thread_get_state", ret);
jl_critical_error(SIGSEGV, (unw_context_t*)&state,
ptls->bt_data, &ptls->bt_size);
return KERN_INVALID_ARGUMENT;
}
}
static void attach_exception_port(thread_port_t thread)
{
kern_return_t ret;
// http://www.opensource.apple.com/source/xnu/xnu-2782.1.97/osfmk/man/thread_set_exception_ports.html
ret = thread_set_exception_ports(thread, EXC_MASK_BAD_ACCESS, segv_port, EXCEPTION_DEFAULT, MACHINE_THREAD_STATE);
HANDLE_MACH_ERROR("thread_set_exception_ports", ret);
}
