2012/6/9 Christoph Lameter <cl@xxxxxxxxx>: > On Sat, 9 Jun 2012, Joonsoo Kim wrote: > >> Current implementation of deactivate_slab() which deactivate >> freelist of kmem_cache_cpu one by one is inefficient. >> This patch changes it to deactivate freelist all at once. >> But, there is no overall performance benefit, >> because deactivate_slab() is invoked infrequently. > > Hmm, deactivate freelist can race with slab_free. Need to look at this in > detail. Implemented logic is nearly same as previous one. I just merge first step of previous deactivate_slab() with second one. In case of failure of cmpxchg_double_slab(), reloading page->freelist, page->counters and recomputing inuse ensure that race with slab_free() cannot be possible. In case that we need a lock, try to get a lock before invoking cmpxchg_double_slab(), so race with slab_free cannot be occured too. Above is my humble opinion, please give me some comments. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>