[PATCH] taskstats: cleanup do_exit() path
do_exit:
taskstats_exit_alloc()
...
taskstats_exit_send()
taskstats_exit_free()
I think this is not good, let it be a single function exported to the core
kernel, taskstats_exit(), which does alloc + send + free itself.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/linux/taskstats_kern.h b/include/linux/taskstats_kern.h
index ce8a912..f1261a5 100644
--- a/include/linux/taskstats_kern.h
+++ b/include/linux/taskstats_kern.h
@@ -15,12 +15,6 @@
extern struct kmem_cache *taskstats_cache;
extern struct mutex taskstats_exit_mutex;
-static inline void taskstats_exit_free(struct taskstats *tidstats)
-{
- if (tidstats)
- kmem_cache_free(taskstats_cache, tidstats);
-}
-
static inline void taskstats_tgid_init(struct signal_struct *sig)
{
sig->stats = NULL;
@@ -54,17 +48,10 @@
kmem_cache_free(taskstats_cache, sig->stats);
}
-extern void taskstats_exit_alloc(struct taskstats **, unsigned int *);
-extern void taskstats_exit_send(struct task_struct *, struct taskstats *, int, unsigned int);
+extern void taskstats_exit(struct task_struct *, int group_dead);
extern void taskstats_init_early(void);
#else
-static inline void taskstats_exit_alloc(struct taskstats **ptidstats, unsigned int *mycpu)
-{}
-static inline void taskstats_exit_free(struct taskstats *ptidstats)
-{}
-static inline void taskstats_exit_send(struct task_struct *tsk,
- struct taskstats *tidstats,
- int group_dead, unsigned int cpu)
+static inline void taskstats_exit(struct task_struct *tsk, int group_dead)
{}
static inline void taskstats_tgid_init(struct signal_struct *sig)
{}
diff --git a/kernel/exit.c b/kernel/exit.c
index 06de6c4..4e3f919 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -850,9 +850,7 @@
fastcall NORET_TYPE void do_exit(long code)
{
struct task_struct *tsk = current;
- struct taskstats *tidstats;
int group_dead;
- unsigned int mycpu;
profile_task_exit(tsk);
@@ -890,8 +888,6 @@
current->comm, current->pid,
preempt_count());
- taskstats_exit_alloc(&tidstats, &mycpu);
-
acct_update_integrals(tsk);
if (tsk->mm) {
update_hiwater_rss(tsk->mm);
@@ -911,8 +907,8 @@
#endif
if (unlikely(tsk->audit_context))
audit_free(tsk);
- taskstats_exit_send(tsk, tidstats, group_dead, mycpu);
- taskstats_exit_free(tidstats);
+
+ taskstats_exit(tsk, group_dead);
exit_mm(tsk);
diff --git a/kernel/taskstats.c b/kernel/taskstats.c
index d9d7c35..2654886 100644
--- a/kernel/taskstats.c
+++ b/kernel/taskstats.c
@@ -119,10 +119,10 @@
/*
* Send taskstats data in @skb to listeners registered for @cpu's exit data
*/
-static void send_cpu_listeners(struct sk_buff *skb, unsigned int cpu)
+static void send_cpu_listeners(struct sk_buff *skb,
+ struct listener_list *listeners)
{
struct genlmsghdr *genlhdr = nlmsg_data((struct nlmsghdr *)skb->data);
- struct listener_list *listeners;
struct listener *s, *tmp;
struct sk_buff *skb_next, *skb_cur = skb;
void *reply = genlmsg_data(genlhdr);
@@ -135,7 +135,6 @@
}
rc = 0;
- listeners = &per_cpu(listener_array, cpu);
down_read(&listeners->sem);
list_for_each_entry(s, &listeners->list, list) {
skb_next = NULL;
@@ -413,28 +412,12 @@
return rc;
}
-void taskstats_exit_alloc(struct taskstats **ptidstats, unsigned int *mycpu)
-{
- struct listener_list *listeners;
- /*
- * This is the cpu on which the task is exiting currently and will
- * be the one for which the exit event is sent, even if the cpu
- * on which this function is running changes later.
- */
- *mycpu = raw_smp_processor_id();
-
- listeners = &per_cpu(listener_array, *mycpu);
-
- *ptidstats = NULL;
- if (!list_empty(&listeners->list))
- *ptidstats = kmem_cache_zalloc(taskstats_cache, GFP_KERNEL);
-}
-
/* Send pid data out on exit */
-void taskstats_exit_send(struct task_struct *tsk, struct taskstats *tidstats,
- int group_dead, unsigned int mycpu)
+void taskstats_exit(struct task_struct *tsk, int group_dead)
{
int rc;
+ struct listener_list *listeners;
+ struct taskstats *tidstats;
struct sk_buff *rep_skb;
void *reply;
size_t size;
@@ -458,12 +441,17 @@
fill_tgid_exit(tsk);
}
+ listeners = &__raw_get_cpu_var(listener_array);
+ if (list_empty(&listeners->list))
+ return;
+
+ tidstats = kmem_cache_zalloc(taskstats_cache, GFP_KERNEL);
if (!tidstats)
return;
rc = prepare_reply(NULL, TASKSTATS_CMD_NEW, &rep_skb, &reply, size);
if (rc < 0)
- goto ret;
+ goto free_stats;
rc = fill_pid(tsk->pid, tsk, tidstats);
if (rc < 0)
@@ -492,15 +480,16 @@
nla_nest_end(rep_skb, na);
send:
- send_cpu_listeners(rep_skb, mycpu);
+ send_cpu_listeners(rep_skb, listeners);
+free_stats:
+ kmem_cache_free(taskstats_cache, tidstats);
return;
nla_put_failure:
genlmsg_cancel(rep_skb, reply);
err_skb:
nlmsg_free(rep_skb);
-ret:
- return;
+ goto free_stats;
}
static struct genl_ops taskstats_ops = {
