lkml.org 
[lkml]   [2011]   [Jun]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH v2] mm: compaction: fix special case -1 order checks
    On Mon, May 30, 2011 at 05:24:50PM +0200, Michal Hocko wrote:
    > <SNIP>
    > mm: compaction: fix special case -1 order checks
    >
    > 56de7263 (mm: compaction: direct compact when a high-order allocation
    > fails) introduced a check for cc->order == -1 in compact_finished. We
    > should continue compacting in that case because the request came from
    > userspace and there is no particular order to compact for.
    > Similar check has been added by 82478fb7 (mm: compaction:
    > prevent division-by-zero during user-requested compaction) for
    > compaction_suitable.
    >
    > The check is, however, done after zone_watermark_ok which uses order as
    > a right hand argument for shifts. Not only watermark check is pointless
    > if we can break out without it but it also uses 1 << -1 which is not
    > well defined (at least from C standard). Let's move the -1 check above
    > zone_watermark_ok.
    >
    > [Minchan Kim <minchan.kim@gmail.com> - caught compaction_suitable]
    > Signed-off-by: Michal Hocko <mhocko@suse.cz>
    > Cc: Mel Gorman <mgorman@suse.de>

    Acked-by: Mel Gorman <mgorman@suse.de>

    --
    Mel Gorman
    SUSE Labs


    \
     
     \ /
      Last update: 2011-06-02 12:41    [W:0.019 / U:32.260 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site