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Diffstat (limited to 'src/thread/pthread_create.c')
-rw-r--r--src/thread/pthread_create.c93
1 files changed, 56 insertions, 37 deletions
diff --git a/src/thread/pthread_create.c b/src/thread/pthread_create.c
index 3da7db14..8761381a 100644
--- a/src/thread/pthread_create.c
+++ b/src/thread/pthread_create.c
@@ -16,12 +16,6 @@ weak_alias(dummy_0, __pthread_tsd_run_dtors);
weak_alias(dummy_0, __do_orphaned_stdio_locks);
weak_alias(dummy_0, __dl_thread_cleanup);
-static void *dummy_1(void *p)
-{
- return 0;
-}
-weak_alias(dummy_1, __start_sched);
-
_Noreturn void __pthread_exit(void *result)
{
pthread_t self = __pthread_self();
@@ -135,21 +129,38 @@ void __do_cleanup_pop(struct __ptcb *cb)
__pthread_self()->cancelbuf = cb->__next;
}
+struct start_args {
+ void *(*start_func)(void *);
+ void *start_arg;
+ pthread_attr_t *attr;
+ volatile int *perr;
+ unsigned long sig_mask[_NSIG/8/sizeof(long)];
+};
+
static int start(void *p)
{
- pthread_t self = p;
- if (self->unblock_cancel)
- __syscall(SYS_rt_sigprocmask, SIG_UNBLOCK,
- SIGPT_SET, 0, _NSIG/8);
- __pthread_exit(self->start(self->start_arg));
+ struct start_args *args = p;
+ if (args->attr) {
+ pthread_t self = __pthread_self();
+ int ret = -__syscall(SYS_sched_setscheduler, self->tid,
+ args->attr->_a_policy, &args->attr->_a_prio);
+ if (a_swap(args->perr, ret)==-2)
+ __wake(args->perr, 1, 1);
+ if (ret) {
+ self->detach_state = DT_DYNAMIC;
+ __pthread_exit(0);
+ }
+ }
+ __syscall(SYS_rt_sigprocmask, SIG_SETMASK, &args->sig_mask, 0, _NSIG/8);
+ __pthread_exit(args->start_func(args->start_arg));
return 0;
}
static int start_c11(void *p)
{
- pthread_t self = p;
- int (*start)(void*) = (int(*)(void*)) self->start;
- __pthread_exit((void *)(uintptr_t)start(self->start_arg));
+ struct start_args *args = p;
+ int (*start)(void*) = (int(*)(void*)) args->start_func;
+ __pthread_exit((void *)(uintptr_t)start(args->start_arg));
return 0;
}
@@ -182,9 +193,9 @@ int __pthread_create(pthread_t *restrict res, const pthread_attr_t *restrict att
unsigned flags = CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND
| CLONE_THREAD | CLONE_SYSVSEM | CLONE_SETTLS
| CLONE_PARENT_SETTID | CLONE_CHILD_CLEARTID | CLONE_DETACHED;
- int do_sched = 0;
pthread_attr_t attr = { 0 };
- struct start_sched_args ssa;
+ sigset_t set;
+ volatile int err = -1;
if (!libc.can_do_threads) return ENOSYS;
self = __pthread_self();
@@ -257,8 +268,6 @@ int __pthread_create(pthread_t *restrict res, const pthread_attr_t *restrict att
new->stack = stack;
new->stack_size = stack - stack_limit;
new->guard_size = guard;
- new->start = entry;
- new->start_arg = arg;
new->self = new;
new->tsd = (void *)tsd;
new->locale = &libc.global_locale;
@@ -268,38 +277,48 @@ int __pthread_create(pthread_t *restrict res, const pthread_attr_t *restrict att
} else {
new->detach_state = DT_JOINABLE;
}
- if (attr._a_sched) {
- do_sched = 1;
- ssa.futex = -1;
- ssa.start_fn = new->start;
- ssa.start_arg = new->start_arg;
- ssa.attr = &attr;
- new->start = __start_sched;
- new->start_arg = &ssa;
- __block_app_sigs(&ssa.mask);
- }
new->robust_list.head = &new->robust_list.head;
- new->unblock_cancel = self->cancel;
new->CANARY = self->CANARY;
+ /* Setup argument structure for the new thread on its stack. */
+ stack -= (uintptr_t)stack % sizeof(uintptr_t);
+ stack -= sizeof(struct start_args);
+ struct start_args *args = (void *)stack;
+ args->start_func = entry;
+ args->start_arg = arg;
+ if (attr._a_sched) {
+ args->attr = &attr;
+ args->perr = &err;
+ } else {
+ args->attr = 0;
+ args->perr = 0;
+ }
+
+ __block_app_sigs(&set);
+
+ /* Ensure SIGCANCEL is unblocked in new thread. This requires
+ * working with a copy of the set so we can restore the
+ * original mask in the calling thread. */
+ memcpy(&args->sig_mask, &set, sizeof args->sig_mask);
+ args->sig_mask[(SIGCANCEL-1)/8/sizeof(long)] &=
+ ~(1UL<<((SIGCANCEL-1)%(8*sizeof(long))));
+
a_inc(&libc.threads_minus_1);
- ret = __clone((c11 ? start_c11 : start), stack, flags, new, &new->tid, TP_ADJ(new), &new->detach_state);
+ ret = __clone((c11 ? start_c11 : start), stack, flags, args, &new->tid, TP_ADJ(new), &new->detach_state);
+ __restore_sigs(&set);
__release_ptc();
- if (do_sched) {
- __restore_sigs(&ssa.mask);
- }
-
if (ret < 0) {
a_dec(&libc.threads_minus_1);
if (map) __munmap(map, size);
return EAGAIN;
}
- if (do_sched) {
- __futexwait(&ssa.futex, -1, 1);
- ret = ssa.futex;
+ if (attr._a_sched) {
+ if (a_cas(&err, -1, -2)==-1)
+ __wait(&err, 0, -2, 1);
+ ret = err;
if (ret) return ret;
}