diff options
| author | San Mehat <san@google.com> | 2010-05-06 15:37:55 -0700 |
|---|---|---|
| committer | Colin Cross <ccross@android.com> | 2010-09-29 17:49:34 -0700 |
| commit | e79ef44016e3dbe611c959bed493c93c3367cfbf (patch) | |
| tree | 51fad4257f9018861c1cb5126ff770b5308b066e /kernel | |
| parent | 9f69ebbf404cf49f9275c1310f1be8f303c87c9b (diff) | |
sched: Add a generic notifier when a task struct is about to be freed
This patch adds a notifier which can be used by subsystems that may
be interested in when a task has completely died and is about to
have it's last resource freed.
The Android lowmemory killer uses this to determine when a task
it has killed has finally given up its goods.
Signed-off-by: San Mehat <san@google.com>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/fork.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/kernel/fork.c b/kernel/fork.c index c445f8cc408d..f3d93ab730c6 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -147,6 +147,9 @@ struct kmem_cache *vm_area_cachep; /* SLAB cache for mm_struct structures (tsk->mm) */ static struct kmem_cache *mm_cachep; +/* Notifier list called when a task struct is freed */ +static ATOMIC_NOTIFIER_HEAD(task_free_notifier); + static void account_kernel_stack(struct thread_info *ti, int account) { struct zone *zone = page_zone(virt_to_page(ti)); @@ -177,6 +180,18 @@ static inline void put_signal_struct(struct signal_struct *sig) free_signal_struct(sig); } +int task_free_register(struct notifier_block *n) +{ + return atomic_notifier_chain_register(&task_free_notifier, n); +} +EXPORT_SYMBOL(task_free_register); + +int task_free_unregister(struct notifier_block *n) +{ + return atomic_notifier_chain_unregister(&task_free_notifier, n); +} +EXPORT_SYMBOL(task_free_unregister); + void __put_task_struct(struct task_struct *tsk) { WARN_ON(!tsk->exit_state); @@ -187,6 +202,7 @@ void __put_task_struct(struct task_struct *tsk) delayacct_tsk_free(tsk); put_signal_struct(tsk->signal); + atomic_notifier_call_chain(&task_free_notifier, 0, tsk); if (!profile_handoff_task(tsk)) free_task(tsk); } |