From: Sebastian Andrzej Siewior Date: Fri, 26 Feb 2021 17:26:04 +0100 Subject: [PATCH 334/342] mm: slub: Don't resize the location tracking cache on PREEMPT_RT Origin: https://git.kernel.org/cgit/linux/kernel/git/rt/linux-stable-rt.git/commit?id=cbb851e2f49e471db5e2ea40478394b48139f4ca The location tracking cache has a size of a page and is resized if its current size is too small. This allocation happens with disabled interrupts and can't happen on PREEMPT_RT. Should one page be too small, then we have to allocate more at the beginning. The only downside is that less callers will be visible. Signed-off-by: Sebastian Andrzej Siewior (cherry picked from commit 87bd0bf324f4c5468ea3d1de0482589f491f3145) Signed-off-by: Clark Williams --- mm/slub.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/slub.c b/mm/slub.c index de80b015fb99..46158ba761ce 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -4591,6 +4591,9 @@ static int alloc_loc_track(struct loc_track *t, unsigned long max, gfp_t flags) struct location *l; int order; + if (IS_ENABLED(CONFIG_PREEMPT_RT) && flags == GFP_ATOMIC) + return 0; + order = get_order(sizeof(struct location) * max); l = (void *)__get_free_pages(flags, order);