lkml.org 
[lkml]   [2009]   [May]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 1/4] mm: Add __GFP_NO_OOM_KILL flag
    Date
    From: Andrew Morton <akpm@linux-foundation.org>

    > > Remind me: why can't we just allocate N pages at suspend-time?
    >
    > We need half of memory free. The reason we can't "just allocate" is
    > probably OOM killer; but my memories are quite weak :-(.

    hm. You'd think that with our splendid range of __GFP_foo falgs, there
    would be some combo which would suit this requirement but I can't
    immediately spot one.

    We can always add another I guess. Something like...

    Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
    ---
    include/linux/gfp.h | 3 ++-
    mm/page_alloc.c | 3 ++-
    2 files changed, 4 insertions(+), 2 deletions(-)

    Index: linux-2.6/mm/page_alloc.c
    ===================================================================
    --- linux-2.6.orig/mm/page_alloc.c
    +++ linux-2.6/mm/page_alloc.c
    @@ -1620,7 +1620,8 @@ nofail_alloc:
    }

    /* The OOM killer will not help higher order allocs so fail */
    - if (order > PAGE_ALLOC_COSTLY_ORDER) {
    + if (order > PAGE_ALLOC_COSTLY_ORDER ||
    + (gfp_mask & __GFP_NO_OOM_KILL)) {
    clear_zonelist_oom(zonelist, gfp_mask);
    goto nopage;
    }
    Index: linux-2.6/include/linux/gfp.h
    ===================================================================
    --- linux-2.6.orig/include/linux/gfp.h
    +++ linux-2.6/include/linux/gfp.h
    @@ -51,8 +51,9 @@ struct vm_area_struct;
    #define __GFP_THISNODE ((__force gfp_t)0x40000u)/* No fallback, no policies */
    #define __GFP_RECLAIMABLE ((__force gfp_t)0x80000u) /* Page is reclaimable */
    #define __GFP_MOVABLE ((__force gfp_t)0x100000u) /* Page is movable */
    +#define __GFP_NO_OOM_KILL ((__force gfp_t)0x200000u) /* Don't invoke out_of_memory() */

    -#define __GFP_BITS_SHIFT 21 /* Room for 21 __GFP_FOO bits */
    +#define __GFP_BITS_SHIFT 22 /* Number of__GFP_FOO bits */
    #define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1))

    /* This equals 0, but use constants in case they ever change */


    \
     
     \ /
      Last update: 2009-05-03 02:29    [W:0.030 / U:0.152 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site