optimize out setting up robust list with kernel when not needed

[oweals/musl.git] / src / process / fork.c

diff --git a/src/process/fork.c b/src/process/fork.c
index bcd47c97a6e117e16c9c4bf534a26b56edc6aec8..8d676828415cac2020f53aad23940d61b858d8ad 100644 (file)
--- a/src/process/fork.c
+++ b/src/process/fork.c
@@ -1,18 +1,35 @@
 #include <unistd.h>
+#include <string.h>
+#include <signal.h>
 #include "syscall.h"
 #include "libc.h"
 #include "pthread_impl.h"
 
+static void dummy(int x)
+{
+}
+
+weak_alias(dummy, __fork_handler);
+
 pid_t fork(void)
 {
        pid_t ret;
-       if (libc.fork_handler) libc.fork_handler(-1);
+       sigset_t set;
+       __fork_handler(-1);
+       __block_all_sigs(&set);
+#ifdef SYS_fork
        ret = syscall(SYS_fork);
-       if (libc.threaded && !ret) {
+#else
+       ret = syscall(SYS_clone, SIGCHLD, 0);
+#endif
+       if (libc.has_thread_pointer && !ret) {
                pthread_t self = __pthread_self();
-               self->tid = self->pid = syscall(SYS_getpid);
+               self->tid = __syscall(SYS_gettid);
+               self->robust_list.off = 0;
+               self->robust_list.pending = 0;
                libc.threads_minus_1 = 0;
        }
-       if (libc.fork_handler) libc.fork_handler(!ret);
+       __restore_sigs(&set);
+       __fork_handler(!ret);
        return ret;
 }