From patchwork Fri May 1 21:05:16 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dave Hansen X-Patchwork-Id: 11523273 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id ADB7492C for ; Fri, 1 May 2020 21:06:58 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 86766216FD for ; Fri, 1 May 2020 21:06:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 86766216FD Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id BAA478E0005; Fri, 1 May 2020 17:06:57 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id B5A678E0001; Fri, 1 May 2020 17:06:57 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A709C8E0005; Fri, 1 May 2020 17:06:57 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0111.hostedemail.com [216.40.44.111]) by kanga.kvack.org (Postfix) with ESMTP id 8C2028E0001 for ; Fri, 1 May 2020 17:06:57 -0400 (EDT) Received: from smtpin30.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 4CE435DD8 for ; Fri, 1 May 2020 21:06:57 +0000 (UTC) X-FDA: 76769384874.30.mom75_1f85291c0b138 X-Spam-Summary: 1,0,0,,d41d8cd98f00b204,dave.hansen@linux.intel.com,,RULES_HIT:30012:30054:30070,0,RBL:134.134.136.20:@linux.intel.com:.lbl8.mailshell.net-62.18.0.100 64.95.201.95,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fn,MSBL:0,DNSBL:none,Custom_rules:0:0:0,LFtime:24,LUA_SUMMARY:none X-HE-Tag: mom75_1f85291c0b138 X-Filterd-Recvd-Size: 1821 Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by imf06.hostedemail.com (Postfix) with ESMTP for ; Fri, 1 May 2020 21:06:56 +0000 (UTC) IronPort-SDR: 4aaLK/EwxKCjI3sx+Pdyrt1o42LER37OsoV8nhF6wRgWNXarN3vDCgcXR/E/78L4xiHAfSX31A lLqTIv5I0xyA== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 May 2020 14:06:55 -0700 IronPort-SDR: t2PqYLdbKCc7wr0GW+Q1DcVZcCRz7MTrjlU96aXv/GRzvAc4vieAEvX6CJuFmCThNzQuhVVW5z c9NusSaHCRow== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,341,1583222400"; d="scan'208";a="283291765" Received: from viggo.jf.intel.com (HELO localhost.localdomain) ([10.54.77.144]) by fmsmga004.fm.intel.com with ESMTP; 01 May 2020 14:06:54 -0700 Subject: [RFC][PATCH 0/2] mm: tweak page cache migration To: linux-kernel@vger.kernel.org Cc: Dave Hansen ,npiggin@gmail.com,akpm@linux-foundation.org,willy@infradead.org,yang.shi@linux.alibaba.com,linux-mm@kvack.org From: Dave Hansen Date: Fri, 01 May 2020 14:05:16 -0700 Message-Id: <20200501210516.DFAFF456@viggo.jf.intel.com> 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: First of all, I think this little slice of code is a bit under-documented. Perhaps this will help clarify things. I'm pretty confident the page_count() check in the first patch is right, which is why I removed it outright. The xas_load() check is a bit murkier, so I just left a warning in for it. Cc: Nicholas Piggin Cc: Andrew Morton Cc: Matthew Wilcox (Oracle) Cc: Yang Shi Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org