slab: NUMA kmem_cache diet
slab: NUMA kmem_cache diet

Some NUMA machines have a big MAX_NUMNODES (possibly 1024), but fewer
possible nodes.  This patch dynamically sizes the 'struct kmem_cache' to
allocate only needed space.

I moved nodelists[] field at the end of struct kmem_cache, and use the
following computation in kmem_cache_init()

cache_cache.buffer_size = offsetof(struct kmem_cache, nodelists) +
                                 nr_node_ids * sizeof(struct kmem_list3 *);

On my two nodes x86_64 machine, kmem_cache.obj_size is now 192 instead of 704
(This is because on x86_64, MAX_NUMNODES is 64)

On bigger NUMA setups, this might reduce the gfporder of "cache_cache"

Signed-off-by: Eric Dumazet <376627c3b2da88577629dab6f8516ef352eb3ff8@cosmosbay.com>
Cc: Pekka Enberg <add4fcd06328a394f0ad91feda7ee057316dc5ed@cs.helsinki.fi>
Cc: Andy Whitcroft <b4658fdd7fbd645c2859b0e39d71018f32058d12@shadowen.org>
Cc: Christoph Lameter <a2610c5c148280bb6730402b12a8276c2f194fbe@engr.sgi.com>
Signed-off-by: Andrew Morton <5c1e68b099950c134891f0b6e179498a8ebe9cf9@linux-foundation.org>
Signed-off-by: Linus Torvalds <69652caca27c8b940640ad396ab71f93cacec34f@linux-foundation.org>

KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas