From mboxrd@z Thu Jan 1 00:00:00 1970 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 66248C433EF for ; Tue, 14 Dec 2021 11:51:57 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A4ADB6B0071; Tue, 14 Dec 2021 06:51:46 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 9FB7E6B0072; Tue, 14 Dec 2021 06:51:46 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8E9176B0074; Tue, 14 Dec 2021 06:51:46 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0107.hostedemail.com [216.40.44.107]) by kanga.kvack.org (Postfix) with ESMTP id 7FB3F6B0071 for ; Tue, 14 Dec 2021 06:51:46 -0500 (EST) Received: from smtpin27.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 232B086E90 for ; Tue, 14 Dec 2021 11:51:36 +0000 (UTC) X-FDA: 78916234992.27.76D3C08 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by imf25.hostedemail.com (Postfix) with ESMTP id DF0D6A0016 for ; Tue, 14 Dec 2021 11:51:31 +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-out2.suse.de (Postfix) with ESMTPS id 2DA891F37C; Tue, 14 Dec 2021 11:51:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1639482694; 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=E6efcRJNZehu3o7Pp7wg4mncnN1XYB+O+/iUJw08HrA=; b=N+yr/RKDb778O9AfUXUH/4yemRO/Zu1rSvAK5VnY52nbNOT76mWDQRs8hNmyy+U0JRiucy whr59dCe5Rs+RUD3pyl9/jwkMQ04++VkC2KrO48A5mSBHvTOc1ytmq6T8VdwbB9k0sb8ys H94tn0/2qk96UHeI1JZ9rT8liH072ws= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1639482694; 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=E6efcRJNZehu3o7Pp7wg4mncnN1XYB+O+/iUJw08HrA=; b=6UFyUQfv4IIfp73uEXTXyhRQ8rqAE6PiaC3V20jG7HRJtfQyHoixx/v9uHJc/3DUQPnd5o xCuleBbwOCKneNBg== 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 EC7E113BA4; Tue, 14 Dec 2021 11:51:33 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id VeH+OEWFuGGbeAAAMHmgww (envelope-from ); Tue, 14 Dec 2021 11:51:33 +0000 Message-ID: <765ffdf0-491b-1f44-21a4-d57138477daf@suse.cz> Date: Tue, 14 Dec 2021 12:51:33 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.4.0 Subject: Re: [PATCH] mm/slob: Remove unnecessary page_mapcount_reset() function call Content-Language: en-US To: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Matthew Wilcox , Christoph Lameter , David Rientjes , Joonsoo Kim , Pekka Enberg , linux-mm@kvack.org, Andrew Morton , patches@lists.linux.dev, Marco Elver , Alexander Potapenko , Dmitry Vyukov , kasan-dev@googlegroups.com References: <20211212065241.GA886691@odroid> From: Vlastimil Babka In-Reply-To: <20211212065241.GA886691@odroid> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: DF0D6A0016 X-Stat-Signature: gjbp3fh7ei44sti8tij7bekknexz1wz6 Authentication-Results: imf25.hostedemail.com; dkim=pass header.d=suse.cz header.s=susede2_rsa header.b="N+yr/RKD"; dkim=pass header.d=suse.cz header.s=susede2_ed25519 header.b=6UFyUQfv; dmarc=none; spf=pass (imf25.hostedemail.com: domain of vbabka@suse.cz designates 195.135.220.29 as permitted sender) smtp.mailfrom=vbabka@suse.cz X-Rspamd-Server: rspam11 X-HE-Tag: 1639482691-124525 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: On 12/12/21 07:52, Hyeonggon Yoo wrote: > After commit f1ac9059ca34 ("mm/sl*b: Differentiate struct slab fields > by sl*b implementations"), we can reorder fields of struct slab > depending on slab allocator. > > For now, page_mapcount_reset() is called because page->_mapcount and > slab->units have same offset. But this is not necessary for > struct slab. Use unused field for units instead. > > Signed-off-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Will add to the series, thanks! > --- > mm/slab.h | 4 ++-- > mm/slob.c | 1 - > 2 files changed, 2 insertions(+), 3 deletions(-) > > diff --git a/mm/slab.h b/mm/slab.h > index 90d7fceba470..dd0480149d38 100644 > --- a/mm/slab.h > +++ b/mm/slab.h > @@ -50,8 +50,8 @@ struct slab { > struct list_head slab_list; > void * __unused_1; > void *freelist; /* first free block */ > - void * __unused_2; > - int units; > + long units; > + unsigned int __unused_2; > > #else > #error "Unexpected slab allocator configured" > diff --git a/mm/slob.c b/mm/slob.c > index 39b651b3e6e7..7b2d2c7d69cc 100644 > --- a/mm/slob.c > +++ b/mm/slob.c > @@ -404,7 +404,6 @@ static void slob_free(void *block, int size) > clear_slob_page_free(sp); > spin_unlock_irqrestore(&slob_lock, flags); > __ClearPageSlab(slab_page(sp)); > - page_mapcount_reset(slab_page(sp)); > slob_free_pages(b, 0); > return; > }