On Fri, 2011-11-11 at 04:30 +0800, Pekka Enberg wrote: > On Thu, Nov 10, 2011 at 10:18 PM, David Rientjes <rientjes@xxxxxxxxxx> wrote: > > On Thu, 10 Nov 2011, Shaohua Li wrote: > > > >> Looks there is a merge error in the slub tree. DEACTIVATE_TO_TAIL != 1. > >> And this will cause performance regression. > >> > >> Signed-off-by: Shaohua Li <shaohua.li@xxxxxxxxx> > >> > >> diff --git a/mm/slub.c b/mm/slub.c > >> index 7d2a996..60e16c4 100644 > >> --- a/mm/slub.c > >> +++ b/mm/slub.c > >> @@ -1904,7 +1904,8 @@ static void unfreeze_partials(struct kmem_cache *s) > >> if (l == M_PARTIAL) > >> remove_partial(n, page); > >> else > >> - add_partial(n, page, 1); > >> + add_partial(n, page, > >> + DEACTIVATE_TO_TAIL); > >> > >> l = m; > >> } > > > > Acked-by: David Rientjes <rientjes@xxxxxxxxxx> > > > > Not sure where the "merge error" is, though, this is how it was proposed > > on linux-mm each time the patch was posted. Probably needs a better title > > and changelog. > > Indeed. Please resend with proper subject and changelog with > Christoph's and David's ACKs included. Subject: slub: use correct parameter to add a page to partial list tail unfreeze_partials() needs add the page to partial list tail, since such page hasn't too many free objects. We now explictly use DEACTIVATE_TO_TAIL for this, while DEACTIVATE_TO_TAIL != 1. This will cause performance regression (eg, more lock contention in node->list_lock) without below fix. Signed-off-by: Shaohua Li <shaohua.li@xxxxxxxxx> Acked-by: Christoph Lameter <cl@xxxxxxxxx> Acked-by: David Rientjes <rientjes@xxxxxxxxxx> diff --git a/mm/slub.c b/mm/slub.c index 7d2a996..60e16c4 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -1904,7 +1904,8 @@ static void unfreeze_partials(struct kmem_cache *s) if (l == M_PARTIAL) remove_partial(n, page); else - add_partial(n, page, 1); + add_partial(n, page, + DEACTIVATE_TO_TAIL); l = m; } -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>