From patchwork Thu Jul 29 13:21:16 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vlastimil Babka X-Patchwork-Id: 12408677 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 93059C4338F for ; Thu, 29 Jul 2021 13:22:23 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 495F560F23 for ; Thu, 29 Jul 2021 13:22:23 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 495F560F23 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.cz Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id AC4DF8D0006; Thu, 29 Jul 2021 09:21:46 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9A7A0900009; Thu, 29 Jul 2021 09:21:46 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E58118D0006; Thu, 29 Jul 2021 09:21:45 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0035.hostedemail.com [216.40.44.35]) by kanga.kvack.org (Postfix) with ESMTP id 8FAC4900007 for ; Thu, 29 Jul 2021 09:21:45 -0400 (EDT) Received: from smtpin02.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 4AEEB22AAE for ; Thu, 29 Jul 2021 13:21:45 +0000 (UTC) X-FDA: 78415687770.02.91F8300 Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.220.28]) by imf20.hostedemail.com (Postfix) with ESMTP id EB24BD0000B8 for ; Thu, 29 Jul 2021 13:21:44 +0000 (UTC) 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-out1.suse.de (Postfix) with ESMTPS id F059F223AF; Thu, 29 Jul 2021 13:21:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1627564903; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=EttZbqFwae0pdlPSjAzhFml11J+ZB6/vwgMLD6ZmLNY=; b=SSB9kfQqJNQwzK/lj2YxZ3Kqrk5JvPexJwuErddaXnpBlbdk9XymcQ9U0qh0m6cC/FIFHb 0BOkAJpdoEVBCm2ZF1wGvmwaqm/P0/jkOaqh8ASBAGHOKtDlJzCepezzj1wOLgc+Igrczf 5y7gORQXjouEf+v0Y+wVnMjNtfND5xE= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1627564903; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=EttZbqFwae0pdlPSjAzhFml11J+ZB6/vwgMLD6ZmLNY=; b=svY3/oEmZ+PSu2aA6kmr3LCPpoYDtJLZ5NbqcXaSD9W1MtRnVB490EAmcPdtRGu00jm7Fv aArSeeYn6HaRUhDA== 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 C279313AF4; Thu, 29 Jul 2021 13:21:43 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id aFrcLmerAmF9AwAAMHmgww (envelope-from ); Thu, 29 Jul 2021 13:21:43 +0000 From: Vlastimil Babka To: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Christoph Lameter , David Rientjes , Pekka Enberg , Joonsoo Kim Cc: Mike Galbraith , Sebastian Andrzej Siewior , Thomas Gleixner , Mel Gorman , Jesper Dangaard Brouer , Jann Horn , Vlastimil Babka Subject: [PATCH v3 19/35] mm, slub: move reset of c->page and freelist out of deactivate_slab() Date: Thu, 29 Jul 2021 15:21:16 +0200 Message-Id: <20210729132132.19691-20-vbabka@suse.cz> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210729132132.19691-1-vbabka@suse.cz> References: <20210729132132.19691-1-vbabka@suse.cz> MIME-Version: 1.0 X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: EB24BD0000B8 Authentication-Results: imf20.hostedemail.com; dkim=pass header.d=suse.cz header.s=susede2_rsa header.b=SSB9kfQq; dkim=pass header.d=suse.cz header.s=susede2_ed25519 header.b="svY3/oEm"; dmarc=none; spf=pass (imf20.hostedemail.com: domain of vbabka@suse.cz designates 195.135.220.28 as permitted sender) smtp.mailfrom=vbabka@suse.cz X-Stat-Signature: zz6f3ftfru5qa9tew61zw3ru61iaxo4g X-HE-Tag: 1627564904-347799 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: deactivate_slab() removes the cpu slab by merging the cpu freelist with slab's freelist and putting the slab on the proper node's list. It also sets the respective kmem_cache_cpu pointers to NULL. By extracting the kmem_cache_cpu operations from the function, we can make it not dependent on disabled irqs. Also if we return a single free pointer from ___slab_alloc, we no longer have to assign kmem_cache_cpu.page before deactivation or care if somebody preempted us and assigned a different page to our kmem_cache_cpu in the process. Signed-off-by: Vlastimil Babka --- mm/slub.c | 31 ++++++++++++++++++------------- 1 file changed, 18 insertions(+), 13 deletions(-) diff --git a/mm/slub.c b/mm/slub.c index 50a4add8983d..7a8554eb3d96 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -2192,10 +2192,13 @@ static void init_kmem_cache_cpus(struct kmem_cache *s) } /* - * Remove the cpu slab + * Finishes removing the cpu slab. Merges cpu's freelist with page's freelist, + * unfreezes the slabs and puts it on the proper list. + * Assumes the slab has been already safely taken away from kmem_cache_cpu + * by the caller. */ static void deactivate_slab(struct kmem_cache *s, struct page *page, - void *freelist, struct kmem_cache_cpu *c) + void *freelist) { enum slab_modes { M_NONE, M_PARTIAL, M_FULL, M_FREE }; struct kmem_cache_node *n = get_node(s, page_to_nid(page)); @@ -2324,9 +2327,6 @@ static void deactivate_slab(struct kmem_cache *s, struct page *page, discard_slab(s, page); stat(s, FREE_SLAB); } - - c->page = NULL; - c->freelist = NULL; } /* @@ -2451,10 +2451,16 @@ static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain) static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) { - stat(s, CPUSLAB_FLUSH); - deactivate_slab(s, c->page, c->freelist, c); + void *freelist = c->freelist; + struct page *page = c->page; + c->page = NULL; + c->freelist = NULL; c->tid = next_tid(c->tid); + + deactivate_slab(s, page, freelist); + + stat(s, CPUSLAB_FLUSH); } /* @@ -2739,7 +2745,10 @@ static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, local_irq_restore(flags); goto reread_page; } - deactivate_slab(s, page, c->freelist, c); + freelist = c->freelist; + c->page = NULL; + c->freelist = NULL; + deactivate_slab(s, page, freelist); local_irq_restore(flags); new_slab: @@ -2818,11 +2827,7 @@ static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, return_single: local_irq_save(flags); - if (unlikely(c->page)) - flush_slab(s, c); - c->page = page; - - deactivate_slab(s, page, get_freepointer(s, freelist), c); + deactivate_slab(s, page, get_freepointer(s, freelist)); local_irq_restore(flags); return freelist; }