lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Mon, 30 Jan 2012 14:06:50 +0100 From: "Michal Nazarewicz" <mina86@...a86.com> To: "Marek Szyprowski" <m.szyprowski@...sung.com>, "Mel Gorman" <mel@....ul.ie> Cc: linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org, linux-media@...r.kernel.org, linux-mm@...ck.org, linaro-mm-sig@...ts.linaro.org, "Kyungmin Park" <kyungmin.park@...sung.com>, "Russell King" <linux@....linux.org.uk>, "Andrew Morton" <akpm@...ux-foundation.org>, "KAMEZAWA Hiroyuki" <kamezawa.hiroyu@...fujitsu.com>, "Daniel Walker" <dwalker@...eaurora.org>, "Arnd Bergmann" <arnd@...db.de>, "Jesse Barker" <jesse.barker@...aro.org>, "Jonathan Corbet" <corbet@....net>, "Shariq Hasnain" <shariq.hasnain@...aro.org>, "Chunsang Jeong" <chunsang.jeong@...aro.org>, "Dave Hansen" <dave@...ux.vnet.ibm.com>, "Benjamin Gaignard" <benjamin.gaignard@...aro.org> Subject: Re: [PATCH 08/15] mm: mmzone: MIGRATE_CMA migration type added > On Thu, Jan 26, 2012 at 10:00:50AM +0100, Marek Szyprowski wrote: >> From: Michal Nazarewicz <mina86@...a86.com> >> @@ -875,10 +895,15 @@ struct page *__rmqueue_smallest(struct zone *zone, unsigned int order, >> * This array describes the order lists are fallen back to when >> * the free lists for the desirable migrate type are depleted >> */ >> -static int fallbacks[MIGRATE_TYPES][3] = { >> +static int fallbacks[MIGRATE_TYPES][4] = { >> [MIGRATE_UNMOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE }, >> [MIGRATE_RECLAIMABLE] = { MIGRATE_UNMOVABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE }, >> +#ifdef CONFIG_CMA >> + [MIGRATE_MOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_CMA , MIGRATE_RESERVE }, On Mon, 30 Jan 2012 13:35:42 +0100, Mel Gorman <mel@....ul.ie> wrote: > This is a curious choice. MIGRATE_CMA is allowed to contain movable > pages. By using MIGRATE_RECLAIMABLE and MIGRATE_UNMOVABLE for movable > pages instead of MIGRATE_CMA, you increase the changes that unmovable > pages will need to use MIGRATE_MOVABLE in the future which impacts > fragmentation avoidance. I would recommend that you change this to > > { MIGRATE_CMA, MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_RESERVE } At the beginning the idea was to try hard not to get pages from MIGRATE_CMA allocated at all, thus it was put at the end of the fallbacks list, but on a busy system this probably won't help anyway, so I'll change it per your suggestion. >> @@ -1017,11 +1049,14 @@ __rmqueue_fallback(struct zone *zone, int order, int start_migratetype) >> rmv_page_order(page); >> >> /* Take ownership for orders >= pageblock_order */ >> - if (current_order >= pageblock_order) >> + if (current_order >= pageblock_order && >> + !is_pageblock_cma(page)) >> change_pageblock_range(page, current_order, >> start_migratetype); >> >> - expand(zone, page, order, current_order, area, migratetype); >> + expand(zone, page, order, current_order, area, >> + is_migrate_cma(start_migratetype) >> + ? start_migratetype : migratetype); >> > > What is this check meant to be doing? > > start_migratetype is determined by allocflags_to_migratetype() and > that never will be MIGRATE_CMA so is_migrate_cma(start_migratetype) > should always be false. Right, thanks! This should be the other way around, ie.: + expand(zone, page, order, current_order, area, + is_migrate_cma(migratetype) + ? migratetype : start_migratetype); I'll fix this and the calls to is_pageblock_cma(). -- Best regards, _ _ .o. | Liege of Serenely Enlightened Majesty of o' \,=./ `o ..o | Computer Science, Michał “mina86” Nazarewicz (o o) ooo +----<email/xmpp: mpn@...gle.com>--------------ooO--(_)--Ooo-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists