static void ti_initthread(int16_t tid)
{
jl_tls_states_t *ptls = jl_get_ptls_states();
#ifndef _OS_WINDOWS_
ptls->system_id = pthread_self();
#endif
ptls->tid = tid;
ptls->pgcstack = NULL;
ptls->gc_state = 0; // GC unsafe
// Conditionally initialize the safepoint address. See comment in
// `safepoint.c`
if (tid == 0) {
ptls->safepoint = (size_t*)(jl_safepoint_pages + jl_page_size);
}
else {
ptls->safepoint = (size_t*)(jl_safepoint_pages + jl_page_size * 2 +
sizeof(size_t));
}
ptls->defer_signal = 0;
ptls->current_module = NULL;
void *bt_data = malloc(sizeof(uintptr_t) * (JL_MAX_BT_SIZE + 1));
if (bt_data == NULL) {
jl_printf(JL_STDERR, "could not allocate backtrace buffer\n");
gc_debug_critical_error();
abort();
}
ptls->bt_data = (uintptr_t*)bt_data;
jl_mk_thread_heap(ptls);
jl_install_thread_signal_handler();
jl_all_tls_states[tid] = ptls;
}
// what to do on a critical error
void jl_critical_error(int sig, bt_context_t *context, uintptr_t *bt_data, size_t *bt_size)
{
// This function is not allowed to reference any TLS variables.
// We need to explicitly pass in the TLS buffer pointer when
// we make `jl_filename` and `jl_lineno` thread local.
size_t i, n = *bt_size;
if (sig)
jl_safe_printf("\nsignal (%d): %s\n", sig, strsignal(sig));
jl_safe_printf("while loading %s, in expression starting on line %d\n", jl_filename, jl_lineno);
if (context)
*bt_size = n = rec_backtrace_ctx(bt_data, JL_MAX_BT_SIZE, context);
for (i = 0; i < n; i++)
jl_gdblookup(bt_data[i] - 1);
gc_debug_print_status();
gc_debug_critical_error();
}
static DWORD WINAPI profile_bt( LPVOID lparam )
{
// Note: illegal to use jl_* functions from this thread
TIMECAPS tc;
if (MMSYSERR_NOERROR!=timeGetDevCaps(&tc, sizeof(tc))) {
fputs("failed to get timer resolution",stderr);
hBtThread = 0;
return 0;
}
while (1) {
if (running && bt_size_cur < bt_size_max) {
DWORD timeout = nsecprof/GIGA;
timeout = min(max(timeout,tc.wPeriodMin*2),tc.wPeriodMax/2);
Sleep(timeout);
if ((DWORD)-1 == SuspendThread(hMainThread)) {
fputs("failed to suspend main thread. aborting profiling.",stderr);
break;
}
CONTEXT ctxThread;
memset(&ctxThread, 0, sizeof(CONTEXT));
ctxThread.ContextFlags = CONTEXT_CONTROL | CONTEXT_INTEGER;
if (!GetThreadContext(hMainThread, &ctxThread)) {
fputs("failed to get context from main thread. aborting profiling.",stderr);
break;
}
// Get backtrace data
bt_size_cur += rec_backtrace_ctx((uintptr_t*)bt_data_prof + bt_size_cur,
bt_size_max - bt_size_cur - 1, &ctxThread);
// Mark the end of this block with 0
bt_data_prof[bt_size_cur] = 0;
bt_size_cur++;
if ((DWORD)-1 == ResumeThread(hMainThread)) {
fputs("failed to resume main thread! aborting.",stderr);
gc_debug_critical_error();
abort();
}
}
else {
SuspendThread(GetCurrentThread());
}
}
hBtThread = 0;
return 0;
}
void jl_safepoint_init(void)
{
// jl_page_size isn't available yet.
size_t pgsz = jl_getpagesize();
#ifdef _OS_WINDOWS_
char *addr = (char*)VirtualAlloc(NULL, pgsz * 3, MEM_COMMIT, PAGE_READONLY);
#else
char *addr = (char*)mmap(0, pgsz * 3, PROT_READ,
MAP_NORESERVE | MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (addr == MAP_FAILED)
addr = NULL;
#endif
if (addr == NULL) {
jl_printf(JL_STDERR, "could not allocate GC synchronization page\n");
gc_debug_critical_error();
abort();
}
// The signal page is for the gc safepoint.
// The page before it is the sigint pending flag.
jl_safepoint_pages = addr;
}