diff options
author | Oleg Nesterov <oleg@tv-sign.ru> | 2006-10-28 10:38:53 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-10-28 11:30:54 -0700 |
commit | b8534d7bd89df0cd41cd47bcd6733a05ea9a691a (patch) | |
tree | c4650f417d7f05a9c645d6a0b1f64405ec4c8a39 /kernel | |
parent | 17b02695b254aa2ef0e53df9c8e6548f86e66a9d (diff) | |
download | op-kernel-dev-b8534d7bd89df0cd41cd47bcd6733a05ea9a691a.zip op-kernel-dev-b8534d7bd89df0cd41cd47bcd6733a05ea9a691a.tar.gz |
[PATCH] taskstats: kill ->taskstats_lock in favor of ->siglock
signal_struct is (mostly) protected by ->sighand->siglock, I think we don't
need ->taskstats_lock to protect ->stats. This also allows us to simplify the
locking in fill_tgid().
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Jay Lan <jlan@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 | 2 | ||||
-rw-r--r-- | kernel/taskstats.c | 16 |
2 files changed, 7 insertions, 11 deletions
diff --git a/kernel/fork.c b/kernel/fork.c index 2133266..3da978e 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -830,7 +830,7 @@ 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->signal); + 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 9aeee51..b2efda9 100644 --- a/kernel/taskstats.c +++ b/kernel/taskstats.c @@ -241,11 +241,11 @@ static int fill_tgid(pid_t tgid, struct task_struct *tgidtsk, tsk = first; read_lock(&tasklist_lock); /* Start with stats from dead tasks */ - if (first->signal) { - spin_lock_irqsave(&first->signal->stats_lock, flags); + if (first->sighand) { + spin_lock_irqsave(&first->sighand->siglock, flags); if (first->signal->stats) memcpy(stats, first->signal->stats, sizeof(*stats)); - spin_unlock_irqrestore(&first->signal->stats_lock, flags); + spin_unlock_irqrestore(&first->sighand->siglock, flags); } do { @@ -276,7 +276,7 @@ static void fill_tgid_exit(struct task_struct *tsk) { unsigned long flags; - spin_lock_irqsave(&tsk->signal->stats_lock, flags); + spin_lock_irqsave(&tsk->sighand->siglock, flags); if (!tsk->signal->stats) goto ret; @@ -288,7 +288,7 @@ static void fill_tgid_exit(struct task_struct *tsk) */ delayacct_add_tsk(tsk->signal->stats, tsk); ret: - spin_unlock_irqrestore(&tsk->signal->stats_lock, flags); + spin_unlock_irqrestore(&tsk->sighand->siglock, flags); return; } @@ -464,15 +464,10 @@ void taskstats_exit_send(struct task_struct *tsk, struct taskstats *tidstats, size_t size; int is_thread_group; struct nlattr *na; - unsigned long flags; if (!family_registered || !tidstats) return; - spin_lock_irqsave(&tsk->signal->stats_lock, flags); - is_thread_group = tsk->signal->stats ? 1 : 0; - spin_unlock_irqrestore(&tsk->signal->stats_lock, flags); - rc = 0; /* * Size includes space for nested attributes @@ -480,6 +475,7 @@ void taskstats_exit_send(struct task_struct *tsk, struct taskstats *tidstats, size = nla_total_size(sizeof(u32)) + nla_total_size(sizeof(struct taskstats)) + nla_total_size(0); + is_thread_group = (tsk->signal->stats != NULL); if (is_thread_group) size = 2 * size; /* PID + STATS + TGID + STATS */ |