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authorOleg Nesterov <oleg@tv-sign.ru>2006-12-06 20:36:52 -0800
committerLinus Torvalds <torvalds@woody.osdl.org>2006-12-07 08:39:34 -0800
commit34ec12349c8a9505adc59d72f92b4595bc2483ff (patch)
tree2307c825f1a0d8bf9976d5fadcc8516ad5829eac /kernel/taskstats.c
parent115085ea0794c0f339be8f9d25505c7f9861d824 (diff)
downloadvexpress-lsk-34ec12349c8a9505adc59d72f92b4595bc2483ff.tar.gz
[PATCH] taskstats: cleanup ->signal->stats allocation
Allocate ->signal->stats on demand in taskstats_exit(), this allows us to remove taskstats_tgid_alloc() (the last non-trivial inline) from taskstat's public interface. 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>
Diffstat (limited to 'kernel/taskstats.c')
-rw-r--r--kernel/taskstats.c26
1 files changed, 25 insertions, 1 deletions
diff --git a/kernel/taskstats.c b/kernel/taskstats.c
index 2654886fe05..7d793d6b1e9 100644
--- a/kernel/taskstats.c
+++ b/kernel/taskstats.c
@@ -412,6 +412,30 @@ err:
return rc;
}
+static struct taskstats *taskstats_tgid_alloc(struct task_struct *tsk)
+{
+ struct signal_struct *sig = tsk->signal;
+ struct taskstats *stats;
+
+ if (sig->stats || thread_group_empty(tsk))
+ goto ret;
+
+ /* No problem if kmem_cache_zalloc() fails */
+ stats = kmem_cache_zalloc(taskstats_cache, GFP_KERNEL);
+
+ spin_lock_irq(&tsk->sighand->siglock);
+ if (!sig->stats) {
+ sig->stats = stats;
+ stats = NULL;
+ }
+ spin_unlock_irq(&tsk->sighand->siglock);
+
+ if (stats)
+ kmem_cache_free(taskstats_cache, stats);
+ret:
+ return sig->stats;
+}
+
/* Send pid data out on exit */
void taskstats_exit(struct task_struct *tsk, int group_dead)
{
@@ -433,7 +457,7 @@ void taskstats_exit(struct task_struct *tsk, int group_dead)
size = nla_total_size(sizeof(u32)) +
nla_total_size(sizeof(struct taskstats)) + nla_total_size(0);
- is_thread_group = (tsk->signal->stats != NULL);
+ is_thread_group = !!taskstats_tgid_alloc(tsk);
if (is_thread_group) {
/* PID + STATS + TGID + STATS */
size = 2 * size;