diff options
Diffstat (limited to 'kernel/trap.c')
| -rw-r--r-- | kernel/trap.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/kernel/trap.c b/kernel/trap.c index 75fb3ec..b879f01 100644 --- a/kernel/trap.c +++ b/kernel/trap.c @@ -53,7 +53,7 @@ usertrap(void) if(r_scause() == 8){ // system call - if(p->killed) + if(__sync_add_and_fetch(&p->killed, 0)) exit(-1); // sepc points to the ecall instruction, @@ -70,10 +70,10 @@ usertrap(void) } else { printf("usertrap(): unexpected scause %p pid=%d\n", r_scause(), p->pid); printf(" sepc=%p stval=%p\n", r_sepc(), r_stval()); - p->killed = 1; + __sync_bool_compare_and_swap(&p->killed, 0, 1); } - if(p->killed) + if(__sync_add_and_fetch(&p->killed, 0)) exit(-1); // give up the CPU if this is a timer interrupt. |