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 9FF43C04A95 for ; Tue, 25 Oct 2022 17:16:55 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 0F9088E0002; Tue, 25 Oct 2022 13:16:55 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0A8CD8E0001; Tue, 25 Oct 2022 13:16:55 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id ED9398E0002; Tue, 25 Oct 2022 13:16:54 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id E1ADA8E0001 for ; Tue, 25 Oct 2022 13:16:54 -0400 (EDT) Received: from smtpin28.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id 871C6A0E94 for ; Tue, 25 Oct 2022 17:16:54 +0000 (UTC) X-FDA: 80060126748.28.4EFACB0 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf21.hostedemail.com (Postfix) with ESMTP id 38F9B1C002F for ; Tue, 25 Oct 2022 17:16:52 +0000 (UTC) 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=W7+Qdona4M4hEcWhfDc47CR8ToDDCX79p0mrQJWdXnY=; b=AbayDTc9h9E3IVE2F+YXbDlLvt t53alW57Mv8zLXN/8GwE9wjWga6IrlpZSviMSpjyitna/vTNPMKKVJsIpk+PpVKLbVNNbxjQHiuLQ EH3+qPGCnlOEFrpuBiIuf7XVIqhQ6ChO9gN2PVl0NKOSucXI5LpE3iMgh8mjypHyuXRnEalmDkZbu Nzw4cUDOhuVhwHX8yyeqdEoyrB6kUUZKWr6BqENDE1/BR6aOZrEOe0SUY1lv7eks5wXP02lXodcjs ezJMAcz59wbH/WB50xow98TA6t6tiCRdUP4Zu6MPaTNlew+CmEjn2kTixuK7COQ1mlNQHL7sBqnPM zJx04RXg==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1onNXp-00GQ7A-6n; Tue, 25 Oct 2022 17:16:53 +0000 Date: Tue, 25 Oct 2022 18:16:53 +0100 From: Matthew Wilcox To: Johannes Weiner Cc: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Eric Bergen Subject: Re: [PATCH] mm: vmscan: split khugepaged stats from direct reclaim stats Message-ID: References: <20221025170519.314511-1-hannes@cmpxchg.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221025170519.314511-1-hannes@cmpxchg.org> ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1666718214; 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=W7+Qdona4M4hEcWhfDc47CR8ToDDCX79p0mrQJWdXnY=; b=Cbat3n48Rixl6DCB3Zf5a1ASC5HJlzCtrKAk6rNNHLyAjP1fI7qvwdfB7I8QuyAk4USMwS itE+qua9hGlAKwKmNlqSKvbXTR6P7rIiNUE+Z9SpUzQTJjfnCdaqSq64wAQ7364yHh89+Y bWqX17gE3MMcemNDo00buO2orpaZdYo= ARC-Authentication-Results: i=1; imf21.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=AbayDTc9; spf=none (imf21.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=1666718214; a=rsa-sha256; cv=none; b=FlnsMHk4RBeMapj9l8WZ+ZDNu7rgnFYERNKm4bFcjMeppk1QoC3N7gqryXnehyRMc8TeqR XtXvl+bJ1egMM3o0aXapRywKaFVep/2uum1JjBQ2b6BKSw8JbAGkKuPC7KBCFe4OrZfPHs Kxfj7k6I3Nr1YbZZBtoStl+iaUZ0okU= Authentication-Results: imf21.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=AbayDTc9; spf=none (imf21.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org; dmarc=none X-Stat-Signature: ew5drmbghfb3q36fitxhimznfbpn7yrn X-Rspamd-Queue-Id: 38F9B1C002F X-Rspamd-Server: rspam07 X-Rspam-User: X-HE-Tag: 1666718212-766364 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 Tue, Oct 25, 2022 at 01:05:19PM -0400, Johannes Weiner wrote: > +static int reclaimer_offset(void) > +{ > + BUILD_BUG_ON(PGSTEAL_DIRECT - PGSTEAL_KSWAPD != 1); > + BUILD_BUG_ON(PGSTEAL_KHUGEPAGED - PGSTEAL_KSWAPD != 2); > + BUILD_BUG_ON(PGDEMOTE_DIRECT - PGDEMOTE_KSWAPD != 1); > + BUILD_BUG_ON(PGDEMOTE_KHUGEPAGED - PGDEMOTE_KSWAPD != 2); > + BUILD_BUG_ON(PGSCAN_DIRECT - PGSCAN_KSWAPD != 1); > + BUILD_BUG_ON(PGSCAN_KHUGEPAGED - PGSCAN_KSWAPD != 2); > + > + if (current_is_kswapd()) > + return 0; > + if (current_is_khugepaged()) > + return 2; > + return 1; > +} Would this be simpler as ... BUILD_BUG_ON(PGSTEAL_DIRECT - PGSTEAL_KSWAPD != PGDEMOTE_DIRECT - PGDEMOTE_KSWAPD); BUILD_BUG_ON(PGSTEAL_DIRECT - PGSTEAL_KSWAPD != PGSCAN_DIRECT - PGSCAN_KSWAPD); BUILD_BUG_ON(PGSTEAL_KHUGEPAGED - PGSTEAL_KSWAPD != PGDEMOTE_KHUGEPAGED - PGDEMOTE_KSWAPD); BUILD_BUG_ON(PGSTEAL_KHUGEPAGED - PGSTEAL_KSWAPD != PGSCAN_KHUGEPAGED - PGDEMOTE_KSWAPD); if (current_is_kswapd()) return 0; if (current_is_khugepaged()) return PGSTEAL_KHUGEPAGED - PGSTEAL_KSWAPD; return PGSTEAL_DIRECT - PGSTEAL_KSWAPD; Not that I think we'd ever want to separate them, but it is perhaps a bit less magic?