On Fri, May 09, 2008 at 01:11:34PM -0700, Andrew Morton wrote: > On Fri, 9 May 2008 10:10:58 -0500 > Russ Anderson <rja@xxxxxxx> wrote: > > > Index: linus/mm/swap.c > > =================================================================== > > --- linus.orig/mm/swap.c 2008-05-09 09:19:40.466984064 -0500 > > +++ linus/mm/swap.c 2008-05-09 09:20:11.330791803 -0500 > > @@ -195,6 +195,8 @@ void lru_cache_add(struct page *page) > > struct pagevec *pvec = &get_cpu_var(lru_add_pvecs); > > > > page_cache_get(page); > > + if (unlikely(PageMemError(page))) > > + return; /* Don't add bad pages to the page list */ > > if (!pagevec_add(pvec, page)) > > __pagevec_lru_add(pvec); > > put_cpu_var(lru_add_pvecs); > > @@ -205,6 +207,8 @@ void lru_cache_add_active(struct page *p > > struct pagevec *pvec = &get_cpu_var(lru_add_active_pvecs); > > > > page_cache_get(page); > > + if (unlikely(PageMemError(page))) > > + return; /* Don't add bad pages to the page list */ > > if (!pagevec_add(pvec, page)) > > __pagevec_lru_add_active(pvec); > > put_cpu_var(lru_add_active_pvecs); > > These PageMemError() tests are happening in some pretty darn hot paths. > But we've gone and added this overhead to a lot of architectures and > configs which don't need it. > > Should we tighten that up? Arrange for PageMemError() to evaluate to > constant zero for all builds which don't actually implement "Migrate data > off physical pages with correctable errors"? Yes. > Probably the way to implement that would be to add a new > CONFIG_NEED_PAGE_MEM_ERROR and `select' that from the appropriate place in > ia64 Kconfig. Which is pretty nasty, but a) we're nasty that way rather > often and b) this time it _is_ a hot-path, so some nastiness is > justifiable. Will do. -- Russ Anderson, OS RAS/Partitioning Project Lead SGI - Silicon Graphics Inc rja@xxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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