Add spinlock to sigstate
@@ -182,6 +182,7 @@ typedef struct sigstate {
u64 saved; /* original mask saved on rt_sigsuspend or handler dispatch */
u64 ignored; /* mask of signals set to SIG_IGN */
u64 interest; /* signals of interest, regardless of mask or ignored */
+ struct spinlock ss_lock;
struct list heads[NSIG];
} *sigstate;
