On Tue, Jan 04, 2022 at 01:10:21AM +0100, Vlastimil Babka wrote:
> From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
>
> In SLUB, use folios, and struct slab to access slab_cache field.
> In SLOB, use folios to properly resolve pointers beyond
> PAGE_SIZE offset of the object.
>
> [ vbabka@xxxxxxx: use folios, and only convert folio_test_slab() == true
> folios to struct slab ]
>
> Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
> Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx>
> Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>
> Reviewed-by: Roman Gushchin <guro@xxxxxx>
> ---
> mm/slob.c | 8 ++++----
> mm/slub.c | 12 +++++-------
> 2 files changed, 9 insertions(+), 11 deletions(-)
>
> diff --git a/mm/slob.c b/mm/slob.c
> index 03deee1e6a94..c8a4290012a6 100644
> --- a/mm/slob.c
> +++ b/mm/slob.c
> @@ -570,7 +570,7 @@ EXPORT_SYMBOL(kfree);
> /* can't use ksize for kmem_cache_alloc memory, only kmalloc */
> size_t __ksize(const void *block)
> {
> - struct page *sp;
> + struct folio *folio;
> int align;
> unsigned int *m;
>
> @@ -578,9 +578,9 @@ size_t __ksize(const void *block)
> if (unlikely(block == ZERO_SIZE_PTR))
> return 0;
>
> - sp = virt_to_page(block);
> - if (unlikely(!PageSlab(sp)))
> - return page_size(sp);
> + folio = virt_to_folio(block);
> + if (unlikely(!folio_test_slab(folio)))
> + return folio_size(folio);
>
> align = max_t(size_t, ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
> m = (unsigned int *)(block - align);
> diff --git a/mm/slub.c b/mm/slub.c
> index c94fb4b4d655..269e10d341a8 100644
> --- a/mm/slub.c
> +++ b/mm/slub.c
> @@ -4527,19 +4527,17 @@ void __check_heap_object(const void *ptr, unsigned long n, struct page *page,
>
> size_t __ksize(const void *object)
> {
> - struct page *page;
> + struct folio *folio;
>
> if (unlikely(object == ZERO_SIZE_PTR))
> return 0;
>
> - page = virt_to_head_page(object);
> + folio = virt_to_folio(object);
>
> - if (unlikely(!PageSlab(page))) {
> - WARN_ON(!PageCompound(page));
> - return page_size(page);
> - }
> + if (unlikely(!folio_test_slab(folio)))
> + return folio_size(folio);
>
> - return slab_ksize(page->slab_cache);
> + return slab_ksize(folio_slab(folio)->slab_cache);
> }
> EXPORT_SYMBOL(__ksize);
>
This patch Looks good.
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@xxxxxxxxx>
BTW, I see no reason to implement SLAB version of __ksize separately.
And there are no modules that use __ksize. EXPORT_SYMBOL is unnecessary.
BTW, Until when can I review your patches? until next week before starting
window?
Thanks!
> --
> 2.34.1
>
