The patch titled Subject: mm/slub: make add_full() condition more explicit has been added to the -mm tree. Its filename is mm-slub-make-add_full-condition-more-explicit.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/mm-slub-make-add_full-condition-more-explicit.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/mm-slub-make-add_full-condition-more-explicit.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Abel Wu <wuyun.wu@xxxxxxxxxx> Subject: mm/slub: make add_full() condition more explicit The commit below is incomplete, as it didn't handle the add_full() part. commit a4d3f8916c65 ("slub: remove useless kmem_cache_debug() before remove_full()") This patch checks for SLAB_STORE_USER instead of kmem_cache_debug(), since that should be the only context in which we need the list_lock for add_full(). Link: https://lkml.kernel.org/r/20200811020240.1231-1-wuyun.wu@xxxxxxxxxx Signed-off-by: Abel Wu <wuyun.wu@xxxxxxxxxx> Cc: Christoph Lameter <cl@xxxxxxxxx> Cc: Pekka Enberg <penberg@xxxxxxxxxx> Cc: David Rientjes <rientjes@xxxxxxxxxx> Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Cc: Liu Xiang <liu.xiang6@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/slub.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/mm/slub.c~mm-slub-make-add_full-condition-more-explicit +++ a/mm/slub.c @@ -2250,7 +2250,8 @@ redo: } } else { m = M_FULL; - if (kmem_cache_debug(s) && !lock) { +#ifdef CONFIG_SLUB_DEBUG + if ((s->flags & SLAB_STORE_USER) && !lock) { lock = 1; /* * This also ensures that the scanning of full @@ -2259,6 +2260,7 @@ redo: */ spin_lock(&n->list_lock); } +#endif } if (l != m) { _ Patches currently in -mm which might be from wuyun.wu@xxxxxxxxxx are mm-slub-branch-optimization-in-free-slowpath.patch mm-slub-fix-missing-alloc_slowpath-stat-when-bulk-alloc.patch mm-slub-make-add_full-condition-more-explicit.patch