Re: [PATCH 2/2] mm: update_page_reclaim_stat() is called form page fault path

[KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>]

> > +void update_page_reclaim_stat(struct page *page)
> > +{
> > +	struct zone *zone = page_zone(page);
> > +
> > +	spin_lock_irq(&zone->lru_lock);
> > +	/* if the page isn't reclaimable, it doesn't update reclaim stat */
> > +	if (PageLRU(page) && !PageUnevictable(page)) {
> > +		update_page_reclaim_stat_locked(zone, page,
> > +					 !!page_is_file_cache(page), 1);
> > +	}
> > +	spin_unlock_irq(&zone->lru_lock);
> > +}
> 
> And we just added a spin_lock_irq() and a bunch of other stuff to it.
> 
> Can we improve this?
> 
> Can we just omit it, even?
> 
> Can we update those stats locklessly and accomodate the resulting
> inaccuracy over at the codesites where these statistics are actually
> used?

fair enough.
thanks good suggestion.

I'm working it on.



--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>