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authorFrans Kaashoek <[email protected]>2022-08-11 14:22:00 -0400
committerFrans Kaashoek <[email protected]>2022-08-11 14:22:00 -0400
commit4f716c8550b406c3e4b3e0c21b986ef99bc06c40 (patch)
tree282dde85659ea25f81c03a4368efa909df65f58e
parent429c7b717edd4c23d3666327986052b9b6eb29eb (diff)
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Use p->lock to read p->killed
-rw-r--r--kernel/defs.h1
-rw-r--r--kernel/proc.c17
-rw-r--r--kernel/trap.c2
3 files changed, 17 insertions, 3 deletions
diff --git a/kernel/defs.h b/kernel/defs.h
index 7181d4d..e38ec00 100644
--- a/kernel/defs.h
+++ b/kernel/defs.h
@@ -91,6 +91,7 @@ pagetable_t proc_pagetable(struct proc *);
void proc_freepagetable(pagetable_t, uint64);
int kill(int);
int killed(struct proc*);
+void setkilled(struct proc*);
struct cpu* mycpu(void);
struct cpu* getmycpu(void);
struct proc* myproc();
diff --git a/kernel/proc.c b/kernel/proc.c
index b4f8a80..5e37cb7 100644
--- a/kernel/proc.c
+++ b/kernel/proc.c
@@ -588,7 +588,7 @@ kill(int pid)
for(p = proc; p < &proc[NPROC]; p++){
acquire(&p->lock);
if(p->pid == pid){
- __atomic_store_n(&p->killed, 1, __ATOMIC_SEQ_CST);
+ p->killed = 1;
if(p->state == SLEEPING){
// Wake process from sleep().
p->state = RUNNABLE;
@@ -601,10 +601,23 @@ kill(int pid)
return -1;
}
+void
+setkilled(struct proc *p)
+{
+ acquire(&p->lock);
+ p->killed = 1;
+ release(&p->lock);
+}
+
int
killed(struct proc *p)
{
- return __atomic_load_n(&p->killed, __ATOMIC_SEQ_CST);
+ int k;
+
+ acquire(&p->lock);
+ k = p->killed;
+ release(&p->lock);
+ return k;
}
// Copy to either a user address, or kernel address,
diff --git a/kernel/trap.c b/kernel/trap.c
index 1039911..44c9cdc 100644
--- a/kernel/trap.c
+++ b/kernel/trap.c
@@ -70,7 +70,7 @@ 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());
- __atomic_store_n(&p->killed, 1, __ATOMIC_SEQ_CST);
+ setkilled(p);
}
if(killed(p))