diff options
| author | Oleg Nesterov <oleg@tv-sign.ru> | 2006-12-06 20:36:52 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.osdl.org> | 2006-12-07 08:39:34 -0800 |
| commit | 34ec12349c8a9505adc59d72f92b4595bc2483ff (patch) | |
| tree | 2307c825f1a0d8bf9976d5fadcc8516ad5829eac /kernel | |
| parent | 115085ea0794c0f339be8f9d25505c7f9861d824 (diff) | |
| download | lwn-34ec12349c8a9505adc59d72f92b4595bc2483ff.tar.gz lwn-34ec12349c8a9505adc59d72f92b4595bc2483ff.zip | |
[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')
| -rw-r--r-- | kernel/fork.c | 1 | ||||
| -rw-r--r-- | kernel/taskstats.c | 26 |
2 files changed, 25 insertions, 2 deletions
diff --git a/kernel/fork.c b/kernel/fork.c index f37980df1d58..658838148647 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -847,7 +847,6 @@ static inline int copy_signal(unsigned long clone_flags, struct task_struct * ts if (clone_flags & CLONE_THREAD) { atomic_inc(¤t->signal->count); atomic_inc(¤t->signal->live); - taskstats_tgid_alloc(current); return 0; } sig = kmem_cache_alloc(signal_cachep, GFP_KERNEL); diff --git a/kernel/taskstats.c b/kernel/taskstats.c index 2654886fe058..7d793d6b1e90 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; |