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 54EBEC27C55 for ; Mon, 10 Jun 2024 13:08:11 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A716C6B0095; Mon, 10 Jun 2024 09:08:10 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9FA3E6B0096; Mon, 10 Jun 2024 09:08:10 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 89AE86B0098; Mon, 10 Jun 2024 09:08:10 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 6C3BB6B0095 for ; Mon, 10 Jun 2024 09:08:10 -0400 (EDT) Received: from smtpin01.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id C9D1D80F13 for ; Mon, 10 Jun 2024 13:08:09 +0000 (UTC) X-FDA: 82215007098.01.5AF2D44 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf30.hostedemail.com (Postfix) with ESMTP id 8685C8000A for ; Mon, 10 Jun 2024 13:08:07 +0000 (UTC) Authentication-Results: imf30.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=MZPcokS3; spf=none (imf30.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org; dmarc=none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1718024888; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=zrYKWWmw4V/ZlIEgWmnUno7t+ZXz7+GHNrH3l1iVN3o=; b=pE416abhqhPzIQFbevip85e1glKcz1zWOEgAkIyW3zx0dAnU4fRk2JCUNgaiqSsonckYXk OGTAc7VwkBmqP1V5vuUTex5T+BMOzfDNF5URNDDc4JfD4j0z7uDDFrjT4zB+cl5oRf4AwE fU5Wl84Zxbk5Blmv4PvuRb/O7PbkwHs= ARC-Authentication-Results: i=1; imf30.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=MZPcokS3; spf=none (imf30.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1718024888; a=rsa-sha256; cv=none; b=OdHHZVpEwknGBCXrvV7R7ic/ztgRcxNMUwo7cZwPqatb3uGm+4yjC7iBhBaTnERr3iCvQW LhrOEcgi3Oat7abB0B+jS1yrd8IbFebu60mgm0txdDtBQJ+/iesYbO4PpXnfLdCN6zDWl3 wMD9Rtv2y03hZiHlBT03bVVxz/jmV38= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=zrYKWWmw4V/ZlIEgWmnUno7t+ZXz7+GHNrH3l1iVN3o=; b=MZPcokS35qGlIRGdqJbwCnA6K0 sk/6bbeZ/oFPqrTkuYcUEvvG7+4Ln0FyGd1e306YZu13Xg8U+NQSK+VztfZcSu2CQuYHwEYk0Qreh yDKHr1ki1A8EI2ztLt9EwUkDuR+wCdOEQ32Oo86FaNFe8A+mWadz71E06+a3hzT/Si4DYyA3h+F/k xFe86x0mjZDUsSEQdhR2zAUDjCjUiOGXvFUYMKeU03gvHP0uPHKETGE9j+Jl9RLe8LeNxAiaET8dF vC5Iji/qcXZvKbwfqs9r2QYUfPazIrFw3hdinC6U1MTcw6iYW/9AH4CPoYgKAEng4RCQxRlD5kXQD EDQKywNw==; Received: from willy by casper.infradead.org with local (Exim 4.97.1 #2 (Red Hat Linux)) id 1sGekh-0000000989e-0ZeJ; Mon, 10 Jun 2024 13:07:59 +0000 Date: Mon, 10 Jun 2024 14:07:59 +0100 From: Matthew Wilcox To: Usama Arif Cc: akpm@linux-foundation.org, hannes@cmpxchg.org, david@redhat.com, ying.huang@intel.com, hughd@google.com, yosryahmed@google.com, nphamcs@gmail.com, chengming.zhou@linux.dev, linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-team@meta.com Subject: Re: [PATCH v3 1/2] mm: store zero pages to be swapped out in a bitmap Message-ID: References: <20240610121820.328876-1-usamaarif642@gmail.com> <20240610121820.328876-2-usamaarif642@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240610121820.328876-2-usamaarif642@gmail.com> X-Rspam-User: X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 8685C8000A X-Stat-Signature: ur1ux3naomefd8mui4asztjamnom1f8z X-HE-Tag: 1718024887-54797 X-HE-Meta: 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 z2LZHC6e 1CJlk6Yk1v6GfamjaiVpaNEbh+L+/vzM8PeSY2MQfAf64y3NC6/LycE3z97p7gB+/4wTGJE0enjLOIRmz1Xz8ylMlhu4roVjbSqj+JJUAxiXDRT3P7E9IYxAPnSMcgOfsp/BBmYz74cfoIsg= 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: List-Subscribe: List-Unsubscribe: On Mon, Jun 10, 2024 at 01:15:59PM +0100, Usama Arif wrote: > + if (is_folio_zero_filled(folio)) { > + swap_zeromap_folio_set(folio); > + folio_start_writeback(folio); > + folio_unlock(folio); > + folio_end_writeback(folio); What's the point? As far as I can see, the only thing this is going to do is spend a lot of time messing with various counters only to end up with incrementing NR_WRITTEN, which is wrong because you didn't actually write it.