diff options
| author | San Mehat <san@google.com> | 2010-05-06 15:37:55 -0700 |
|---|---|---|
| committer | Gary King <gking@nvidia.com> | 2010-05-23 14:43:11 -0700 |
| commit | b6cd3d7da6fb112fd790777cbb20b42c4e6dfb16 (patch) | |
| tree | e9f8ba10b689e1f193b9ac6debe1246a8451ffce /kernel | |
| parent | 1a4e47a795c7c787e3a8aeff066440e5a51b7474 (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 166b8c49257c..2cfa6dcfd44f 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -138,6 +138,9 @@ 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)); @@ -156,6 +159,18 @@ void free_task(struct task_struct *tsk) } EXPORT_SYMBOL(free_task); +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); @@ -165,6 +180,7 @@ void __put_task_struct(struct task_struct *tsk) exit_creds(tsk); delayacct_tsk_free(tsk); + atomic_notifier_call_chain(&task_free_notifier, 0, tsk); if (!profile_handoff_task(tsk)) free_task(tsk); } |