[PATCH v2 11/33] mm/slub: Convert kfree() to use a struct slab
From: Vlastimil Babka <hidden>
Date: 2021-12-01 18:20:58
Also in:
linux-patches
Subsystem:
memory management, slab allocator, the rest · Maintainers:
Andrew Morton, Vlastimil Babka, Harry Yoo, Linus Torvalds
From: "Matthew Wilcox (Oracle)" <willy@infradead.org> Convert kfree(), kmem_cache_free() and ___cache_free() to resolve object addresses to struct slab, using folio as intermediate step where needed. Keep passing the result as struct page for now in preparation for mass conversion of internal functions. [ vbabka@suse.cz: Use folio as intermediate step when checking for large kmalloc pages ] Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Vlastimil Babka <redacted> --- mm/slub.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-)
diff --git a/mm/slub.c b/mm/slub.c
index 9bdb0a5d6ab2..2d9c1b3c9f37 100644
--- a/mm/slub.c
+++ b/mm/slub.c@@ -3517,7 +3517,7 @@ static __always_inline void slab_free(struct kmem_cache *s, struct page *page, #ifdef CONFIG_KASAN_GENERIC void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr) { - do_slab_free(cache, virt_to_head_page(x), x, NULL, 1, addr); + do_slab_free(cache, slab_page(virt_to_slab(x)), x, NULL, 1, addr); } #endif
@@ -3527,7 +3527,7 @@ void kmem_cache_free(struct kmem_cache *s, void *x) if (!s) return; trace_kmem_cache_free(_RET_IP_, x, s->name); - slab_free(s, virt_to_head_page(x), x, NULL, 1, _RET_IP_); + slab_free(s, slab_page(virt_to_slab(x)), x, NULL, 1, _RET_IP_); } EXPORT_SYMBOL(kmem_cache_free);
@@ -4546,7 +4546,8 @@ EXPORT_SYMBOL(__ksize); void kfree(const void *x) { - struct page *page; + struct folio *folio; + struct slab *slab; void *object = (void *)x; trace_kfree(_RET_IP_, x);
@@ -4554,12 +4555,13 @@ void kfree(const void *x) if (unlikely(ZERO_OR_NULL_PTR(x))) return; - page = virt_to_head_page(x); - if (unlikely(!PageSlab(page))) { - free_nonslab_page(page, object); + folio = virt_to_folio(x); + if (unlikely(!folio_test_slab(folio))) { + free_nonslab_page(folio_page(folio, 0), object); return; } - slab_free(page->slab_cache, page, object, NULL, 1, _RET_IP_); + slab = folio_slab(folio); + slab_free(slab->slab_cache, slab_page(slab), object, NULL, 1, _RET_IP_); } EXPORT_SYMBOL(kfree);
--
2.33.1