From patchwork Mon Nov 20 18:34:27 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vlastimil Babka X-Patchwork-Id: 13461910 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=suse.cz header.i=@suse.cz header.b="GurbnCGj"; dkim=permerror (0-bit key) header.d=suse.cz header.i=@suse.cz header.b="2KGJL7ZA" Received: from smtp-out2.suse.de (smtp-out2.suse.de [IPv6:2001:67c:2178:6::1d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AA37A10C; Mon, 20 Nov 2023 10:34:45 -0800 (PST) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 34F561F8C0; Mon, 20 Nov 2023 18:34:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1700505283; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=0dd/IArvjIRWfQN3Q+n8Y43IiuEYmqtBXkwN7diMKwU=; b=GurbnCGj79cofMqZNPG5ggQmlEGil9xl2Qc9QDrDU876ARGhNDVN6UHUcgTrd/RgAiAp6q wq48EYqN9pInZujNhWLyDFmzJ3B8jZC+++PZaNdFghIMT84xO9p0za0gTakob1u3XyyZPG 8xvARXzCWa9lZ3irelYfoUecZM6zhnQ= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1700505283; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=0dd/IArvjIRWfQN3Q+n8Y43IiuEYmqtBXkwN7diMKwU=; b=2KGJL7ZAkrwa/Tpv3q3xTY10kiRMrlQOQHqsN8kMGpf3r3mzdtqg/dSVXVYujQtdsvMJEg YhrpXfvL6XTCEDDA== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id F1FA313499; Mon, 20 Nov 2023 18:34:42 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id QEOSOsKmW2UUMgAAMHmgww (envelope-from ); Mon, 20 Nov 2023 18:34:42 +0000 From: Vlastimil Babka Date: Mon, 20 Nov 2023 19:34:27 +0100 Subject: [PATCH v2 16/21] mm/slab: move kfree() from slab_common.c to slub.c Precedence: bulk X-Mailing-List: linux-hardening@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20231120-slab-remove-slab-v2-16-9c9c70177183@suse.cz> References: <20231120-slab-remove-slab-v2-0-9c9c70177183@suse.cz> In-Reply-To: <20231120-slab-remove-slab-v2-0-9c9c70177183@suse.cz> To: David Rientjes , Christoph Lameter , Pekka Enberg , Joonsoo Kim Cc: Andrew Morton , Hyeonggon Yoo <42.hyeyoo@gmail.com>, Roman Gushchin , Andrey Ryabinin , Alexander Potapenko , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , Marco Elver , Johannes Weiner , Michal Hocko , Shakeel Butt , Muchun Song , Kees Cook , linux-mm@kvack.org, linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, cgroups@vger.kernel.org, linux-hardening@vger.kernel.org, Vlastimil Babka X-Mailer: b4 0.12.4 Authentication-Results: smtp-out2.suse.de; none X-Spam-Level: X-Spam-Score: -6.79 X-Spamd-Result: default: False [-6.79 / 50.00]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; RCVD_TLS_ALL(0.00)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; FREEMAIL_ENVRCPT(0.00)[gmail.com]; TO_MATCH_ENVRCPT_ALL(0.00)[]; TAGGED_RCPT(0.00)[]; MIME_GOOD(-0.10)[text/plain]; REPLY(-4.00)[]; MID_RHS_MATCH_FROM(0.00)[]; NEURAL_HAM_LONG(-1.00)[-1.000]; R_RATELIMIT(0.00)[to_ip_from(RL563rtnmcmc9sawm86hmgtctc)]; DKIM_SIGNED(0.00)[suse.cz:s=susede2_rsa,suse.cz:s=susede2_ed25519]; NEURAL_HAM_SHORT(-0.20)[-1.000]; BAYES_HAM(-2.99)[99.94%]; RCPT_COUNT_TWELVE(0.00)[24]; FUZZY_BLOCKED(0.00)[rspamd.com]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; FREEMAIL_CC(0.00)[linux-foundation.org,gmail.com,linux.dev,google.com,arm.com,cmpxchg.org,kernel.org,chromium.org,kvack.org,vger.kernel.org,googlegroups.com,suse.cz]; RCVD_COUNT_TWO(0.00)[2]; SUSPICIOUS_RECIPS(1.50)[] This should result in better code. Currently kfree() makes a function call between compilation units to __kmem_cache_free() which does its own virt_to_slab(), throwing away the struct slab pointer we already had in kfree(). Now it can be reused. Additionally kfree() can now inline the whole SLUB freeing fastpath. Also move over free_large_kmalloc() as the only callsites are now in slub.c, and make it static. Reviewed-by: Kees Cook Signed-off-by: Vlastimil Babka Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> --- mm/slab.h | 4 ---- mm/slab_common.c | 45 --------------------------------------------- mm/slub.c | 51 ++++++++++++++++++++++++++++++++++++++++++++++----- 3 files changed, 46 insertions(+), 54 deletions(-) diff --git a/mm/slab.h b/mm/slab.h index 5ae6a978e9c2..35a55c4a407d 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -395,8 +395,6 @@ struct kmem_cache *kmalloc_slab(size_t size, gfp_t flags, unsigned long caller); void *__kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int node, size_t orig_size, unsigned long caller); -void __kmem_cache_free(struct kmem_cache *s, void *x, unsigned long caller); - gfp_t kmalloc_fix_flags(gfp_t flags); /* Functions provided by the slab allocators */ @@ -559,8 +557,6 @@ static inline int memcg_alloc_slab_cgroups(struct slab *slab, } #endif /* CONFIG_MEMCG_KMEM */ -void free_large_kmalloc(struct folio *folio, void *object); - size_t __ksize(const void *objp); static inline size_t slab_ksize(const struct kmem_cache *s) diff --git a/mm/slab_common.c b/mm/slab_common.c index bbc2e3f061f1..f4f275613d2a 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -963,22 +963,6 @@ void __init create_kmalloc_caches(slab_flags_t flags) slab_state = UP; } -void free_large_kmalloc(struct folio *folio, void *object) -{ - unsigned int order = folio_order(folio); - - if (WARN_ON_ONCE(order == 0)) - pr_warn_once("object pointer: 0x%p\n", object); - - kmemleak_free(object); - kasan_kfree_large(object); - kmsan_kfree_large(object); - - mod_lruvec_page_state(folio_page(folio, 0), NR_SLAB_UNRECLAIMABLE_B, - -(PAGE_SIZE << order)); - __free_pages(folio_page(folio, 0), order); -} - static void *__kmalloc_large_node(size_t size, gfp_t flags, int node); static __always_inline void *__do_kmalloc_node(size_t size, gfp_t flags, int node, unsigned long caller) @@ -1023,35 +1007,6 @@ void *__kmalloc_node_track_caller(size_t size, gfp_t flags, } EXPORT_SYMBOL(__kmalloc_node_track_caller); -/** - * kfree - free previously allocated memory - * @object: pointer returned by kmalloc() or kmem_cache_alloc() - * - * If @object is NULL, no operation is performed. - */ -void kfree(const void *object) -{ - struct folio *folio; - struct slab *slab; - struct kmem_cache *s; - - trace_kfree(_RET_IP_, object); - - if (unlikely(ZERO_OR_NULL_PTR(object))) - return; - - folio = virt_to_folio(object); - if (unlikely(!folio_test_slab(folio))) { - free_large_kmalloc(folio, (void *)object); - return; - } - - slab = folio_slab(folio); - s = slab->slab_cache; - __kmem_cache_free(s, (void *)object, _RET_IP_); -} -EXPORT_SYMBOL(kfree); - /** * __ksize -- Report full size of underlying allocation * @object: pointer to the object diff --git a/mm/slub.c b/mm/slub.c index cc801f8258fe..2baa9e94d9df 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -4197,11 +4197,6 @@ static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x) return cachep; } -void __kmem_cache_free(struct kmem_cache *s, void *x, unsigned long caller) -{ - slab_free(s, virt_to_slab(x), x, NULL, &x, 1, caller); -} - /** * kmem_cache_free - Deallocate an object * @s: The cache the allocation was from. @@ -4220,6 +4215,52 @@ void kmem_cache_free(struct kmem_cache *s, void *x) } EXPORT_SYMBOL(kmem_cache_free); +static void free_large_kmalloc(struct folio *folio, void *object) +{ + unsigned int order = folio_order(folio); + + if (WARN_ON_ONCE(order == 0)) + pr_warn_once("object pointer: 0x%p\n", object); + + kmemleak_free(object); + kasan_kfree_large(object); + kmsan_kfree_large(object); + + mod_lruvec_page_state(folio_page(folio, 0), NR_SLAB_UNRECLAIMABLE_B, + -(PAGE_SIZE << order)); + __free_pages(folio_page(folio, 0), order); +} + +/** + * kfree - free previously allocated memory + * @object: pointer returned by kmalloc() or kmem_cache_alloc() + * + * If @object is NULL, no operation is performed. + */ +void kfree(const void *object) +{ + struct folio *folio; + struct slab *slab; + struct kmem_cache *s; + void *x = (void *)object; + + trace_kfree(_RET_IP_, object); + + if (unlikely(ZERO_OR_NULL_PTR(object))) + return; + + folio = virt_to_folio(object); + if (unlikely(!folio_test_slab(folio))) { + free_large_kmalloc(folio, (void *)object); + return; + } + + slab = folio_slab(folio); + s = slab->slab_cache; + slab_free(s, slab, x, NULL, &x, 1, _RET_IP_); +} +EXPORT_SYMBOL(kfree); + struct detached_freelist { struct slab *slab; void *tail;