lkml.org 
[lkml]   [2010]   [Jul]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    Subject[S+Q2 18/19] SLUB: Remove MAX_OBJS limitation
    There is no need anymore for the "inuse" field in the page struct.
    Extend the objects field to 32 bit allowing a practically unlimited
    number of objects.

    Signed-off-by: Christoph Lameter <cl@linux-foundation.org>

    ---
    include/linux/mm_types.h | 5 +----
    mm/slub.c | 7 -------
    2 files changed, 1 insertion(+), 11 deletions(-)

    Index: linux-2.6/include/linux/mm_types.h
    ===================================================================
    --- linux-2.6.orig/include/linux/mm_types.h 2010-07-07 10:54:05.000000000 -0500
    +++ linux-2.6/include/linux/mm_types.h 2010-07-07 10:54:36.000000000 -0500
    @@ -40,10 +40,7 @@ struct page {
    * to show when page is mapped
    * & limit reverse map searches.
    */
    - struct { /* SLUB */
    - u16 inuse;
    - u16 objects;
    - };
    + u32 objects; /* SLUB */
    };
    union {
    struct {
    Index: linux-2.6/mm/slub.c
    ===================================================================
    --- linux-2.6.orig/mm/slub.c 2010-07-07 10:54:33.000000000 -0500
    +++ linux-2.6/mm/slub.c 2010-07-07 10:54:36.000000000 -0500
    @@ -145,7 +145,6 @@ static inline int kmem_cache_debug(struc

    #define OO_SHIFT 16
    #define OO_MASK ((1 << OO_SHIFT) - 1)
    -#define MAX_OBJS_PER_PAGE 65535 /* since page.objects is u16 */

    /* Internal SLUB flags */
    #define __OBJECT_POISON 0x80000000UL /* Poison object */
    @@ -768,9 +767,6 @@ static int verify_slab(struct kmem_cache
    max_objects = ((void *)page->freelist - start) / s->size;
    }

    - if (max_objects > MAX_OBJS_PER_PAGE)
    - max_objects = MAX_OBJS_PER_PAGE;
    -
    if (page->objects != max_objects) {
    slab_err(s, page, "Wrong number of objects. Found %d but "
    "should be %d", page->objects, max_objects);
    @@ -1984,9 +1980,6 @@ static inline int slab_order(int size, i
    int rem;
    int min_order = slub_min_order;

    - if ((PAGE_SIZE << min_order) / size > MAX_OBJS_PER_PAGE)
    - return get_order(size * MAX_OBJS_PER_PAGE) - 1;
    -
    for (order = max(min_order,
    fls(min_objects * size - 1) - PAGE_SHIFT);
    order <= max_order; order++) {


    \
     
     \ /
      Last update: 2010-07-09 21:15    [W:4.288 / U:0.312 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site