• Christoph Lameter's avatar
    Slab allocators: define common size limitations · 0aa817f0
    Christoph Lameter authored
    Currently we have a maze of configuration variables that determine the
    maximum slab size.  Worst of all it seems to vary between SLAB and SLUB.
    
    So define a common maximum size for kmalloc.  For conveniences sake we use
    the maximum size ever supported which is 32 MB.  We limit the maximum size
    to a lower limit if MAX_ORDER does not allow such large allocations.
    
    For many architectures this patch will have the effect of adding large
    kmalloc sizes.  x86_64 adds 5 new kmalloc sizes.  So a small amount of
    memory will be needed for these caches (contemporary SLAB has dynamically
    sizeable node and cpu structure so the waste is less than in the past)
    
    Most architectures will then be able to allocate object with sizes up to
    MAX_ORDER.  We have had repeated breakage (in fact whenever we doubled the
    number of supported processors) on IA64 because one or the other struct
    grew beyond what the slab allocators supported.  This will avoid future
    issues and f.e.  avoid fixes for 2k and 4k cpu support.
    
    CONFIG_LARGE_ALLOCS is no longer necessary so drop it.
    
    It fixes sparc64 with SLAB.
    Signed-off-by: default avatarChristoph Lameter <clameter@sgi.com>
    Signed-off-by: default avatar"David S. Miller" <davem@davemloft.net>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    0aa817f0
kmalloc_sizes.h 724 Bytes