On Sat, Mar 09, 2019 at 03:02:22PM +0900, Tetsuo Handa wrote:
> @@ -1120,8 +1122,13 @@ void pagefault_out_of_memory(void)
> if (mem_cgroup_oom_synchronize(true))
> return;
>
> - if (!mutex_trylock(&oom_lock))
> + if (!mutex_trylock(&oom_lock)) {
/*
* Explain why we still need this on the fail back.
*/
> + oom_reclaim_acquire(GFP_KERNEL, 0);
> + oom_reclaim_release(GFP_KERNEL, 0);
> return;
> + }
/*
* This changes the try-lock to a regular lock; because .....
* text goes here.
*/
> + oom_reclaim_release(GFP_KERNEL, 0);
> + oom_reclaim_acquire(GFP_KERNEL, 0);
> out_of_memory(&oc);
> mutex_unlock(&oom_lock);
> }
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 6d0fa5b..e8853a19 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -3793,6 +3793,8 @@ void warn_alloc(gfp_t gfp_mask, nodemask_t *nodemask, const char *fmt, ...)
> schedule_timeout_uninterruptible(1);
> return NULL;
> }
idem
> + oom_reclaim_release(gfp_mask, order);
> + oom_reclaim_acquire(gfp_mask, order);
>
> /*
> * Go through the zonelist yet one more time, keep very high watermark
these things might seem 'obvious' now, but I'm sure that the next time I
see this I'll go WTF?!
