From nobody Fri Dec 19 04:52:22 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3C344EE8011 for ; Fri, 8 Sep 2023 14:53:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244134AbjIHOxa (ORCPT ); Fri, 8 Sep 2023 10:53:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56672 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244103AbjIHOxZ (ORCPT ); Fri, 8 Sep 2023 10:53:25 -0400 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CA35F1FC1 for ; Fri, 8 Sep 2023 07:53:20 -0700 (PDT) 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 825EA1FEFF; Fri, 8 Sep 2023 14:53:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1694184799; 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=TBS/rfQAa9CuGAOXLs/AG66+kZ+35/pxxXJ2H3zd1io=; b=AErap95nCfprazdQmp9OXffnXycQVwIbGZpHDVA0rP1sASRm6I/cAKuQEAWyQwn3yPrIhj n2us9Yv71zG8n60xarSDoURo97o0UJr6tPpUw1eQl5dNdrsDvGofv7aMgtveGRu7mN2InU ErsEOQVo1bhO94LeTmRRs1dVrdIzL/Y= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1694184799; 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=TBS/rfQAa9CuGAOXLs/AG66+kZ+35/pxxXJ2H3zd1io=; b=PBQchTCPYcBZU1rMZMkGvd3jPhMJtIy0CS2wp+p1ullQX6NqzbDhx7UDZYJDCdQdtJKh3v ubVT/MasEOcFelDA== 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 59E68131FD; Fri, 8 Sep 2023 14:53:19 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id iIFAFV81+2QaBQAAMHmgww (envelope-from ); Fri, 08 Sep 2023 14:53:19 +0000 From: Vlastimil Babka To: David Rientjes , Christoph Lameter , Hyeonggon Yoo <42.hyeyoo@gmail.com>, Jay Patel Cc: Roman Gushchin , Pekka Enberg , Joonsoo Kim , linux-mm@kvack.org, patches@lists.linux.dev, linux-kernel@vger.kernel.org, Vlastimil Babka Subject: [PATCH 4/4] mm/slub: refactor calculate_order() and calc_slab_order() Date: Fri, 8 Sep 2023 16:53:07 +0200 Message-ID: <20230908145302.30320-10-vbabka@suse.cz> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230908145302.30320-6-vbabka@suse.cz> References: <20230908145302.30320-6-vbabka@suse.cz> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" After the previous cleanups, we can now move some code from calc_slab_order() to calculate_order() so it's executed just once, and do some more cleanups. - move the min_order and MAX_OBJS_PER_PAGE evaluation to calc_slab_order(). - change calc_slab_order() parameter min_objects to min_order Also make MAX_OBJS_PER_PAGE check more robust by considering also min_objects in addition to slub_min_order. Otherwise this is not a functional change. Signed-off-by: Vlastimil Babka Reviewed-by: Feng Tang --- mm/slub.c | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) diff --git a/mm/slub.c b/mm/slub.c index f04eb029d85a..1c91f72c7239 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -4110,17 +4110,12 @@ static unsigned int slub_min_objects; * the smallest order which will fit the object. */ static inline unsigned int calc_slab_order(unsigned int size, - unsigned int min_objects, unsigned int max_order, + unsigned int min_order, unsigned int max_order, unsigned int fract_leftover) { - unsigned int min_order =3D slub_min_order; unsigned int order; =20 - if (order_objects(min_order, size) > MAX_OBJS_PER_PAGE) - return get_order(size * MAX_OBJS_PER_PAGE) - 1; - - for (order =3D max(min_order, (unsigned int)get_order(min_objects * size)= ); - order <=3D max_order; order++) { + for (order =3D min_order; order <=3D max_order; order++) { =20 unsigned int slab_size =3D (unsigned int)PAGE_SIZE << order; unsigned int rem; @@ -4139,7 +4134,7 @@ static inline int calculate_order(unsigned int size) unsigned int order; unsigned int min_objects; unsigned int max_objects; - unsigned int nr_cpus; + unsigned int min_order; =20 min_objects =3D slub_min_objects; if (!min_objects) { @@ -4152,7 +4147,7 @@ static inline int calculate_order(unsigned int size) * order on systems that appear larger than they are, and too * low order on systems that appear smaller than they are. */ - nr_cpus =3D num_present_cpus(); + unsigned int nr_cpus =3D num_present_cpus(); if (nr_cpus <=3D 1) nr_cpus =3D nr_cpu_ids; min_objects =3D 4 * (fls(nr_cpus) + 1); @@ -4160,6 +4155,10 @@ static inline int calculate_order(unsigned int size) max_objects =3D order_objects(slub_max_order, size); min_objects =3D min(min_objects, max_objects); =20 + min_order =3D max(slub_min_order, (unsigned int)get_order(min_objects * s= ize)); + if (order_objects(min_order, size) > MAX_OBJS_PER_PAGE) + return get_order(size * MAX_OBJS_PER_PAGE) - 1; + /* * Attempt to find best configuration for a slab. This works by first * attempting to generate a layout with the best possible configuration a= nd @@ -4176,7 +4175,7 @@ static inline int calculate_order(unsigned int size) * long as at least single object fits within slub_max_order. */ for (unsigned int fraction =3D 16; fraction > 1; fraction /=3D 2) { - order =3D calc_slab_order(size, min_objects, slub_max_order, + order =3D calc_slab_order(size, min_order, slub_max_order, fraction); if (order <=3D slub_max_order) return order; --=20 2.42.0