Commit 29c696e1 authored by Vladimir Davydov's avatar Vladimir Davydov Committed by Linus Torvalds
Browse files

oom: make oom_reaper_list single linked



Entries are only added/removed from oom_reaper_list at head so we can
use a single linked list and hence save a word in task_struct.

Signed-off-by: default avatarVladimir Davydov <vdavydov@virtuozzo.com>
Signed-off-by: default avatarMichal Hocko <mhocko@suse.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 855b0183
......@@ -1852,7 +1852,7 @@ struct task_struct {
#endif
int pagefault_disabled;
#ifdef CONFIG_MMU
struct list_head oom_reaper_list;
struct task_struct *oom_reaper_list;
#endif
/* CPU-specific state of this task */
struct thread_struct thread;
......
......@@ -419,7 +419,7 @@ bool oom_killer_disabled __read_mostly;
*/
static struct task_struct *oom_reaper_th;
static DECLARE_WAIT_QUEUE_HEAD(oom_reaper_wait);
static LIST_HEAD(oom_reaper_list);
static struct task_struct *oom_reaper_list;
static DEFINE_SPINLOCK(oom_reaper_lock);
......@@ -528,13 +528,11 @@ static int oom_reaper(void *unused)
while (true) {
struct task_struct *tsk = NULL;
wait_event_freezable(oom_reaper_wait,
(!list_empty(&oom_reaper_list)));
wait_event_freezable(oom_reaper_wait, oom_reaper_list != NULL);
spin_lock(&oom_reaper_lock);
if (!list_empty(&oom_reaper_list)) {
tsk = list_first_entry(&oom_reaper_list,
struct task_struct, oom_reaper_list);
list_del(&tsk->oom_reaper_list);
if (oom_reaper_list != NULL) {
tsk = oom_reaper_list;
oom_reaper_list = tsk->oom_reaper_list;
}
spin_unlock(&oom_reaper_lock);
......@@ -553,7 +551,8 @@ static void wake_oom_reaper(struct task_struct *tsk)
get_task_struct(tsk);
spin_lock(&oom_reaper_lock);
list_add(&tsk->oom_reaper_list, &oom_reaper_list);
tsk->oom_reaper_list = oom_reaper_list;
oom_reaper_list = tsk;
spin_unlock(&oom_reaper_lock);
wake_up(&oom_reaper_wait);
}
......
Supports Markdown
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment