Messages in this thread | | | Date | Thu, 5 Nov 2015 05:31:39 -0800 | From | Andrew Morton <> | Subject | Re: [PATCH] mm: slab: Only move management objects off-slab for sizes larger than KMALLOC_MIN_SIZE |
| |
On Thu, 5 Nov 2015 11:50:35 +0000 Catalin Marinas <catalin.marinas@arm.com> wrote:
> Commit 8fc9cf420b36 ("slab: make more slab management structure off the > slab") enables off-slab management objects for sizes starting with > PAGE_SIZE >> 5. This means 128 bytes for a 4KB page configuration. > However, on systems with a KMALLOC_MIN_SIZE of 128 (arm64 in 4.4), such > optimisation does not make sense since the slab management allocation > would take 128 bytes anyway (even though freelist_size is 32) with the > additional overhead of another allocation. > > This patch introduces an OFF_SLAB_MIN_SIZE macro which takes > KMALLOC_MIN_SIZE into account. It also solves a slab bug on arm64 where > the first kmalloc_cache to be initialised after slab_early_init = 0, > "kmalloc-128", fails to allocate off-slab management objects from the > same "kmalloc-128" cache.
That all seems to be quite minor stuff.
> Fixes: 8fc9cf420b36 ("slab: make more slab management structure off the slab") > Cc: <stable@vger.kernel.org> # 3.15+
Yet you believe the fix should be backported.
So, the usual refrain: when fixing a bug, please describe the end-user visible effects of that bug.
| |