fork: Provide kmemcache based thread_info allocator

Several architectures have their own kmemcache based thread allocator
because THREAD_SIZE is smaller than PAGE_SIZE. Add it to the core code
conditionally on THREAD_SIZE < PAGE_SIZE so the private copies can go.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20120505150141.491002124@linutronix.de
This commit is contained in:
Thomas Gleixner 2012-05-05 15:05:41 +00:00
parent 67ba5293f7
commit 0d15d74a1e
1 changed files with 27 additions and 0 deletions

View File

@ -132,6 +132,11 @@ static inline void free_task_struct(struct task_struct *tsk)
void __weak arch_release_thread_info(struct thread_info *ti) { }
/*
* Allocate pages if THREAD_SIZE is >= PAGE_SIZE, otherwise use a
* kmemcache based allocator.
*/
# if THREAD_SIZE >= PAGE_SIZE
static struct thread_info *alloc_thread_info_node(struct task_struct *tsk,
int node)
{
@ -146,6 +151,28 @@ static inline void free_thread_info(struct thread_info *ti)
arch_release_thread_info(ti);
free_pages((unsigned long)ti, THREAD_SIZE_ORDER);
}
# else
static struct kmem_cache *thread_info_cache;
static struct thread_info *alloc_thread_info_node(struct task_struct *tsk,
int node)
{
return kmem_cache_alloc_node(thread_info_cache, THREADINFO_GFP, node);
}
static void free_thread_info(struct thread_info *ti)
{
arch_release_thread_info(ti);
kmem_cache_free(thread_info_cache, ti);
}
void thread_info_cache_init(void)
{
thread_info_cache = kmem_cache_create("thread_info", THREAD_SIZE,
THREAD_SIZE, 0, NULL);
BUG_ON(thread_info_cache == NULL);
}
# endif
#endif
/* SLAB cache for signal_struct structures (tsk->signal) */