X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=src%2Fthread%2Fpthread_create.c;h=6cbf85b32e052342032a09fc2e0f43530a9b7f25;hb=8c4be3e2209d2a1d3874b8bc2b474668fcbbbac6;hp=c8c117b9e87adc15a35de7bef68ec5df204e8d41;hpb=b092f1c5fa9c048e12d002c7b972df5ecbe96d1d;p=musl

diff --git a/src/thread/pthread_create.c b/src/thread/pthread_create.c
index c8c117b9..6cbf85b3 100644
--- a/src/thread/pthread_create.c
+++ b/src/thread/pthread_create.c
@@ -3,6 +3,12 @@
 #include "stdio_impl.h"
 #include "libc.h"
 #include <sys/mman.h>
+#include <string.h>
+#include <stddef.h>
+
+void *__mmap(void *, size_t, int, int, int, off_t);
+int __munmap(void *, size_t);
+int __mprotect(void *, size_t, int);
 
 static void dummy_0()
 {
@@ -10,13 +16,16 @@ static void dummy_0()
 weak_alias(dummy_0, __acquire_ptc);
 weak_alias(dummy_0, __release_ptc);
 weak_alias(dummy_0, __pthread_tsd_run_dtors);
-weak_alias(dummy_0, __do_private_robust_list);
+weak_alias(dummy_0, __do_orphaned_stdio_locks);
+weak_alias(dummy_0, __dl_thread_cleanup);
 
-_Noreturn void pthread_exit(void *result)
+_Noreturn void __pthread_exit(void *result)
 {
 	pthread_t self = __pthread_self();
 	sigset_t set;
 
+	self->canceldisable = 1;
+	self->cancelasync = 0;
 	self->result = result;
 
 	while (self->cancelbuf) {
@@ -58,13 +67,27 @@ _Noreturn void pthread_exit(void *result)
 		exit(0);
 	}
 
-	if (self->locale != &libc.global_locale) {
-		a_dec(&libc.uselocale_cnt);
-		if (self->locale->ctype_utf8)
-			a_dec(&libc.bytelocale_cnt_minus_1);
+	/* Process robust list in userspace to handle non-pshared mutexes
+	 * and the detached thread case where the robust list head will
+	 * be invalid when the kernel would process it. */
+	__vm_lock();
+	volatile void *volatile *rp;
+	while ((rp=self->robust_list.head) && rp != &self->robust_list.head) {
+		pthread_mutex_t *m = (void *)((char *)rp
+			- offsetof(pthread_mutex_t, _m_next));
+		int waiters = m->_m_waiters;
+		int priv = (m->_m_type & 128) ^ 128;
+		self->robust_list.pending = rp;
+		self->robust_list.head = *rp;
+		int cont = a_swap(&m->_m_lock, 0x40000000);
+		self->robust_list.pending = 0;
+		if (cont < 0 || waiters)
+			__wake(&m->_m_lock, 1, priv);
 	}
+	__vm_unlock();
 
-	__do_private_robust_list();
+	__do_orphaned_stdio_locks();
+	__dl_thread_cleanup();
 
 	if (self->detached && self->map_base) {
 		/* Detached threads must avoid the kernel clear_child_tid
@@ -76,6 +99,15 @@ _Noreturn void pthread_exit(void *result)
 		 * detached later (== 2), we need to clear it here. */
 		if (self->detached == 2) __syscall(SYS_set_tid_address, 0);
 
+		/* Robust list will no longer be valid, and was already
+		 * processed above, so unregister it with the kernel. */
+		if (self->robust_list.off)
+			__syscall(SYS_set_robust_list, 0, 3*sizeof(long));
+
+		/* Since __unmapself bypasses the normal munmap code path,
+		 * explicitly wait for vmlock holders first. */
+		__vm_wait();
+
 		/* The following call unmaps the thread's stack mapping
 		 * and then exits without touching the stack. */
 		__unmapself(self->map_base, self->map_size);
@@ -86,7 +118,6 @@ _Noreturn void pthread_exit(void *result)
 
 void __do_cleanup_push(struct __ptcb *cb)
 {
-	if (!libc.has_thread_pointer) return;
 	struct pthread *self = __pthread_self();
 	cb->__next = self->cancelbuf;
 	self->cancelbuf = cb;
@@ -94,16 +125,20 @@ void __do_cleanup_push(struct __ptcb *cb)
 
 void __do_cleanup_pop(struct __ptcb *cb)
 {
-	if (!libc.has_thread_pointer) return;
 	__pthread_self()->cancelbuf = cb->__next;
 }
 
 static int start(void *p)
 {
 	pthread_t self = p;
+	/* States for startlock:
+	 * 0 = no need for start sync
+	 * 1 = waiting for parent to do work
+	 * 2 = failure in parent, child must abort
+	 * 3 = success in parent, child must restore sigmask */
 	if (self->startlock[0]) {
 		__wait(self->startlock, 0, 1, 1);
-		if (self->startlock[0]) {
+		if (self->startlock[0] == 2) {
 			self->detached = 2;
 			pthread_exit(0);
 		}
@@ -112,7 +147,15 @@ static int start(void *p)
 	if (self->unblock_cancel)
 		__syscall(SYS_rt_sigprocmask, SIG_UNBLOCK,
 			SIGPT_SET, 0, _NSIG/8);
-	pthread_exit(self->start(self->start_arg));
+	__pthread_exit(self->start(self->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));
 	return 0;
 }
 
@@ -124,6 +167,10 @@ weak_alias(dummy, __pthread_tsd_size);
 static void *dummy_tsd[1] = { 0 };
 weak_alias(dummy_tsd, __pthread_tsd_main);
 
+volatile int __block_new_threads = 0;
+size_t __default_stacksize = DEFAULT_STACK_SIZE;
+size_t __default_guardsize = DEFAULT_GUARD_SIZE;
+
 static FILE *volatile dummy_file = 0;
 weak_alias(dummy_file, __stdin_used);
 weak_alias(dummy_file, __stdout_used);
@@ -136,9 +183,9 @@ static void init_file_lock(FILE *f)
 
 void *__copy_tls(unsigned char *);
 
-int pthread_create(pthread_t *restrict res, const pthread_attr_t *restrict attrp, void *(*entry)(void *), void *restrict arg)
+int __pthread_create(pthread_t *restrict res, const pthread_attr_t *restrict attrp, void *(*entry)(void *), void *restrict arg)
 {
-	int ret;
+	int ret, c11 = (attrp == __ATTRP_C11_THREAD);
 	size_t size, guard;
 	struct pthread *self, *new;
 	unsigned char *map = 0, *stack = 0, *tsd = 0, *stack_limit;
@@ -146,13 +193,14 @@ int pthread_create(pthread_t *restrict res, const pthread_attr_t *restrict attrp
 		| CLONE_THREAD | CLONE_SYSVSEM | CLONE_SETTLS
 		| CLONE_PARENT_SETTID | CLONE_CHILD_CLEARTID | CLONE_DETACHED;
 	int do_sched = 0;
-	pthread_attr_t attr = {0};
+	pthread_attr_t attr = { 0 };
 
 	if (!libc.can_do_threads) return ENOSYS;
 	self = __pthread_self();
 	if (!libc.threaded) {
-		for (FILE *f=libc.ofl_head; f; f=f->next)
+		for (FILE *f=*__ofl_lock(); f; f=f->next)
 			init_file_lock(f);
+		__ofl_unlock();
 		init_file_lock(__stdin_used);
 		init_file_lock(__stdout_used);
 		init_file_lock(__stderr_used);
@@ -160,13 +208,19 @@ int pthread_create(pthread_t *restrict res, const pthread_attr_t *restrict attrp
 		self->tsd = (void **)__pthread_tsd_main;
 		libc.threaded = 1;
 	}
-	if (attrp) attr = *attrp;
+	if (attrp && !c11) attr = *attrp;
 
 	__acquire_ptc();
+	if (!attrp || c11) {
+		attr._a_stacksize = __default_stacksize;
+		attr._a_guardsize = __default_guardsize;
+	}
+
+	if (__block_new_threads) __wait(&__block_new_threads, 0, 1, 1);
 
 	if (attr._a_stackaddr) {
 		size_t need = libc.tls_size + __pthread_tsd_size;
-		size = attr._a_stacksize + DEFAULT_STACK_SIZE;
+		size = attr._a_stacksize;
 		stack = (void *)(attr._a_stackaddr & -16);
 		stack_limit = (void *)(attr._a_stackaddr - size);
 		/* Use application-provided stack for TLS only when
@@ -175,26 +229,28 @@ int pthread_create(pthread_t *restrict res, const pthread_attr_t *restrict attrp
 		if (need < size/8 && need < 2048) {
 			tsd = stack - __pthread_tsd_size;
 			stack = tsd - libc.tls_size;
+			memset(stack, 0, need);
 		} else {
 			size = ROUND(need);
 			guard = 0;
 		}
 	} else {
-		guard = ROUND(DEFAULT_GUARD_SIZE + attr._a_guardsize);
-		size = guard + ROUND(DEFAULT_STACK_SIZE + attr._a_stacksize
+		guard = ROUND(attr._a_guardsize);
+		size = guard + ROUND(attr._a_stacksize
 			+ libc.tls_size +  __pthread_tsd_size);
 	}
 
 	if (!tsd) {
 		if (guard) {
-			map = mmap(0, size, PROT_NONE, MAP_PRIVATE|MAP_ANON, -1, 0);
+			map = __mmap(0, size, PROT_NONE, MAP_PRIVATE|MAP_ANON, -1, 0);
 			if (map == MAP_FAILED) goto fail;
-			if (mprotect(map+guard, size-guard, PROT_READ|PROT_WRITE)) {
-				munmap(map, size);
+			if (__mprotect(map+guard, size-guard, PROT_READ|PROT_WRITE)
+			    && errno != ENOSYS) {
+				__munmap(map, size);
 				goto fail;
 			}
 		} else {
-			map = mmap(0, size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANON, -1, 0);
+			map = __mmap(0, size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANON, -1, 0);
 			if (map == MAP_FAILED) goto fail;
 		}
 		tsd = map + size - __pthread_tsd_size;
@@ -222,11 +278,12 @@ int pthread_create(pthread_t *restrict res, const pthread_attr_t *restrict attrp
 		do_sched = new->startlock[0] = 1;
 		__block_app_sigs(new->sigmask);
 	}
+	new->robust_list.head = &new->robust_list.head;
 	new->unblock_cancel = self->cancel;
-	new->canary = self->canary;
+	new->CANARY = self->CANARY;
 
 	a_inc(&libc.threads_minus_1);
-	ret = __clone(start, stack, flags, new, &new->tid, TP_ADJ(new), &new->tid);
+	ret = __clone((c11 ? start_c11 : start), stack, flags, new, &new->tid, TP_ADJ(new), &new->tid);
 
 	__release_ptc();
 
@@ -236,14 +293,14 @@ int pthread_create(pthread_t *restrict res, const pthread_attr_t *restrict attrp
 
 	if (ret < 0) {
 		a_dec(&libc.threads_minus_1);
-		if (map) munmap(map, size);
+		if (map) __munmap(map, size);
 		return EAGAIN;
 	}
 
 	if (do_sched) {
 		ret = __syscall(SYS_sched_setscheduler, new->tid,
 			attr._a_policy, &attr._a_prio);
-		a_store(new->startlock, ret<0 ? 2 : 0);
+		a_store(new->startlock, ret<0 ? 2 : 3);
 		__wake(new->startlock, 1, 1);
 		if (ret < 0) return -ret;
 	}
@@ -254,3 +311,6 @@ fail:
 	__release_ptc();
 	return EAGAIN;
 }
+
+weak_alias(__pthread_exit, pthread_exit);
+weak_alias(__pthread_create, pthread_create);