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 65B2FC433EF for ; Thu, 12 May 2022 20:02:58 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id EF6208D0002; Thu, 12 May 2022 16:02:57 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id EA6536B007B; Thu, 12 May 2022 16:02:57 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D51EA8D0002; Thu, 12 May 2022 16:02:57 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id C7BF76B0078 for ; Thu, 12 May 2022 16:02:57 -0400 (EDT) Received: from smtpin10.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id A52CCA7F for ; Thu, 12 May 2022 20:02:57 +0000 (UTC) X-FDA: 79458164394.10.8EEA95D Received: from mail-pj1-f43.google.com (mail-pj1-f43.google.com [209.85.216.43]) by imf07.hostedemail.com (Postfix) with ESMTP id 958D040003 for ; Thu, 12 May 2022 20:02:50 +0000 (UTC) Received: by mail-pj1-f43.google.com with SMTP id cq17-20020a17090af99100b001dc0386cd8fso5827942pjb.5 for ; Thu, 12 May 2022 13:02:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:from:to:cc:subject:in-reply-to:message-id:references :mime-version; bh=eR3WQru4FWKNvvXqipWEAmLeBfu0npX5uycv6YSB0H8=; b=Umj+pLBQdQP4mVJ2SbUcYxiHBEuj+Bp/jROb16D59i2K7K7WdipmlmReMTHBQNCrSM ZwCW5qJf0nzKXyvHlEd40Vc1FQRIqbOkEPdwTi9Kix2DRCm4NXS/L/EpidzEdbjVnZr5 cLHiU6MkllTkIYvOxQcHywywDA1XoPirnI+jyY9qW6ZFd+nRmqDLDUrPq037NK+75RyQ bkzOrbKThGRnePnit+rjE3lnajTvmCx/ZHT2uEJTJUH5X7jkHXAR3VgOKr8d2nd8DQ0e WFyzbovCSzZxyWPBtfR8pB3/qV4ukxbtS5DrSgIKHUgTuayI55YuvfCVQuCQhWe4ZAqz rAmw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:in-reply-to:message-id :references:mime-version; bh=eR3WQru4FWKNvvXqipWEAmLeBfu0npX5uycv6YSB0H8=; b=MGYiTSnWkGdQp9lgealKtwR+hPhpmO38VfH7gdvspYcXmo5mgN9jnRS1ptbmiDJanh itBdYhWLCC8kDiyxAVH5GcBMpD98/sV1Y8wuVWPfia1jnmVlkQqvpmT+frCuocjq//2R 1VDjt2eUPtUluRDutThpmiJGPDQTyEaAViRaAAAE84Iw7Fkz6ZdBPTElnnd2PuHLxMEa d3bd8LhPSpmqNZOKW2OrFQ1MS88Bbaez7L8WgvEelDthW4v1+E3hzOPVRoCsK49erwU9 2D5YYeBz0CQGcYLxkWdMn7K1nHuoqCOu+X4GuegN40yj+Tu8Oqp0GroHCRFPndm8V0M6 UozQ== X-Gm-Message-State: AOAM531Y45+4Ug4CZMnupFA4dtFWYRGi7AMa9ZKSEzGNhdb2qWzFWf/z zq9pkxqTg58MRFqpnhHy3S7w2Q== X-Google-Smtp-Source: ABdhPJxY2QQkj7y8X52QReSt1+FJcinZA8/x879gxEZ4ZQKnqE1+9k47jC8jBE2vWtyzFamMM3wpZg== X-Received: by 2002:a17:902:d896:b0:15e:fb07:ba92 with SMTP id b22-20020a170902d89600b0015efb07ba92mr1468528plz.148.1652385776080; Thu, 12 May 2022 13:02:56 -0700 (PDT) Received: from [2620:15c:29:204:8122:ccb0:c783:c757] ([2620:15c:29:204:8122:ccb0:c783:c757]) by smtp.gmail.com with ESMTPSA id gn21-20020a17090ac79500b001d903861194sm2206317pjb.30.2022.05.12.13.02.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 12 May 2022 13:02:55 -0700 (PDT) Date: Thu, 12 May 2022 13:02:55 -0700 (PDT) From: David Rientjes To: Zach O'Keefe cc: Alex Shi , David Hildenbrand , Matthew Wilcox , Michal Hocko , Pasha Tatashin , Peter Xu , SeongJae Park , Song Liu , Vlastimil Babka , Yang Shi , Zi Yan , linux-mm@kvack.org, Andrea Arcangeli , Andrew Morton , Arnd Bergmann , Axel Rasmussen , Chris Kennelly , Chris Zankel , Helge Deller , Hugh Dickins , Ivan Kokshaysky , "James E.J. Bottomley" , Jens Axboe , "Kirill A. Shutemov" , Matt Turner , Max Filippov , Miaohe Lin , Minchan Kim , Patrick Xia , Pavel Begunkov , Thomas Bogendoerfer Subject: Re: [PATCH v5 04/13] mm/khugepaged: make hugepage allocation context-specific In-Reply-To: <20220504214437.2850685-5-zokeefe@google.com> Message-ID: References: <20220504214437.2850685-1-zokeefe@google.com> <20220504214437.2850685-5-zokeefe@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Authentication-Results: imf07.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=Umj+pLBQ; dmarc=pass (policy=reject) header.from=google.com; spf=pass (imf07.hostedemail.com: domain of rientjes@google.com designates 209.85.216.43 as permitted sender) smtp.mailfrom=rientjes@google.com X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 958D040003 X-Rspam-User: X-Stat-Signature: skocitaygrx7y3auqwz9c8koni4aszti X-HE-Tag: 1652385770-921536 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 Wed, 4 May 2022, Zach O'Keefe wrote: > diff --git a/mm/khugepaged.c b/mm/khugepaged.c > index c94bc43dff3e..6095fcb3f07c 100644 > --- a/mm/khugepaged.c > +++ b/mm/khugepaged.c > @@ -92,6 +92,10 @@ struct collapse_control { > > /* Last target selected in khugepaged_find_target_node() */ > int last_target_node; > + > + struct page *hpage; > + int (*alloc_charge_hpage)(struct mm_struct *mm, > + struct collapse_control *cc); > }; > > /** Embedding this function pointer into collapse_contol seems like it would need some pretty strong rationale. Not to say that it should be a non-starter, but I think the changelog needs to clearly indicate why this is better/cleaner than embedding the needed info for a single allocation and charge function to use. If the callbacks would truly be so different that unifying them would be more complex, I think this makes sense.