• Glauber Costa's avatar
    slab: propagate tunable values · 943a451a
    Glauber Costa authored
    SLAB allows us to tune a particular cache behavior with tunables.  When
    creating a new memcg cache copy, we'd like to preserve any tunables the
    parent cache already had.
    
    This could be done by an explicit call to do_tune_cpucache() after the
    cache is created.  But this is not very convenient now that the caches are
    created from common code, since this function is SLAB-specific.
    
    Another method of doing that is taking advantage of the fact that
    do_tune_cpucache() is always called from enable_cpucache(), which is
    called at cache initialization.  We can just preset the values, and then
    things work as expected.
    
    It can also happen that a root cache has its tunables updated during
    normal system operation.  In this case, we will propagate the change to
    all caches that are already active.
    
    This change will require us to move the assignment of root_cache in
    memcg_params a bit earlier.  We need this to be already set - which
    memcg_kmem_register_cache will do - when we reach __kmem_cache_create()
    Signed-off-by: default avatarGlauber Costa <glommer@parallels.com>
    Cc: Christoph Lameter <cl@linux.com>
    Cc: David Rientjes <rientjes@google.com>
    Cc: Frederic Weisbecker <fweisbec@redhat.com>
    Cc: Greg Thelen <gthelen@google.com>
    Cc: Johannes Weiner <hannes@cmpxchg.org>
    Cc: JoonSoo Kim <js1304@gmail.com>
    Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
    Cc: Mel Gorman <mel@csn.ul.ie>
    Cc: Michal Hocko <mhocko@suse.cz>
    Cc: Pekka Enberg <penberg@cs.helsinki.fi>
    Cc: Rik van Riel <riel@redhat.com>
    Cc: Suleiman Souhlal <suleiman@google.com>
    Cc: Tejun Heo <tj@kernel.org>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    943a451a
slab.h 6.24 KB