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-rw-r--r--kernel/taskstats.c24
1 files changed, 19 insertions, 5 deletions
diff --git a/kernel/taskstats.c b/kernel/taskstats.c
index abb59e32354..f45179ce028 100644
--- a/kernel/taskstats.c
+++ b/kernel/taskstats.c
@@ -51,6 +51,7 @@ __read_mostly = {
struct listener {
struct list_head list;
pid_t pid;
+ char valid;
};
struct listener_list {
@@ -127,7 +128,7 @@ static int send_cpu_listeners(struct sk_buff *skb, unsigned int cpu)
struct listener *s, *tmp;
struct sk_buff *skb_next, *skb_cur = skb;
void *reply = genlmsg_data(genlhdr);
- int rc, ret;
+ int rc, ret, delcount = 0;
rc = genlmsg_end(skb, reply);
if (rc < 0) {
@@ -137,7 +138,7 @@ static int send_cpu_listeners(struct sk_buff *skb, unsigned int cpu)
rc = 0;
listeners = &per_cpu(listener_array, cpu);
- down_write(&listeners->sem);
+ down_read(&listeners->sem);
list_for_each_entry_safe(s, tmp, &listeners->list, list) {
skb_next = NULL;
if (!list_is_last(&s->list, &listeners->list)) {
@@ -150,14 +151,26 @@ static int send_cpu_listeners(struct sk_buff *skb, unsigned int cpu)
}
ret = genlmsg_unicast(skb_cur, s->pid);
if (ret == -ECONNREFUSED) {
- list_del(&s->list);
- kfree(s);
+ s->valid = 0;
+ delcount++;
rc = ret;
}
skb_cur = skb_next;
}
- up_write(&listeners->sem);
+ up_read(&listeners->sem);
+
+ if (!delcount)
+ return rc;
+ /* Delete invalidated entries */
+ down_write(&listeners->sem);
+ list_for_each_entry_safe(s, tmp, &listeners->list, list) {
+ if (!s->valid) {
+ list_del(&s->list);
+ kfree(s);
+ }
+ }
+ up_write(&listeners->sem);
return rc;
}
@@ -290,6 +303,7 @@ static int add_del_listener(pid_t pid, cpumask_t *maskp, int isadd)
goto cleanup;
s->pid = pid;
INIT_LIST_HEAD(&s->list);
+ s->valid = 1;
listeners = &per_cpu(listener_array, cpu);
down_write(&listeners->sem);