diff options
Diffstat (limited to 'kernel/taskstats.c')
| -rw-r--r-- | kernel/taskstats.c | 26 |
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; |