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 X-Spam-Level: X-Spam-Status: No, score=-3.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A92FAC433F5 for ; Wed, 22 Sep 2021 11:28:23 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 62B0F61131 for ; Wed, 22 Sep 2021 11:28:23 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 62B0F61131 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id D2BE36B006C; Wed, 22 Sep 2021 07:28:22 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id CDB616B0072; Wed, 22 Sep 2021 07:28:22 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BCA6B900002; Wed, 22 Sep 2021 07:28:22 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0191.hostedemail.com [216.40.44.191]) by kanga.kvack.org (Postfix) with ESMTP id ACC916B006C for ; Wed, 22 Sep 2021 07:28:22 -0400 (EDT) Received: from smtpin05.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 53CC030161 for ; Wed, 22 Sep 2021 11:28:22 +0000 (UTC) X-FDA: 78614986044.05.B1FBD4B Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) by imf13.hostedemail.com (Postfix) with ESMTP id 723AE12753BC for ; Wed, 22 Sep 2021 11:28:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; 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=D7ZSl4YWEnGCJruUgFbe6upY9ZIlVKrfq0rf1wn9qT4=; b=bpBVu4IjgGl0Zdm/lkC2DT5zDD IhqLDeZhP/xM0SbN4iNNX7YYqL9GuSxmrTDAaLhFK27VashqlEnQ2VXBC0Lfp0Wvvl/sXmsnb+ugw hfyQjy61RtFfG2mwcw3i/dWbKC1UkAxey2W/3bolaSXZjkN3F9ND/B0R3rV6TCUDUV62Y4g2HW8jf Ul15D8IR+ZtAwEcVkNEQgKADdTCzvPqIUtyKaJLv1idSFLkeq5yAWbHuG0u/dsKc3qkHDieX7c50o UjFf2lfi2EK8du47kNWIO40f3sGcSmrix9/myZOWr7pqXuTWFlttdRQHMn7gt6+ROw3vY9bP5njv3 YAM+81pA==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=worktop.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1mT0QE-004yj0-Li; Wed, 22 Sep 2021 11:28:18 +0000 Received: by worktop.programming.kicks-ass.net (Postfix, from userid 1000) id 493529816EA; Wed, 22 Sep 2021 13:28:17 +0200 (CEST) Date: Wed, 22 Sep 2021 13:28:17 +0200 From: Peter Zijlstra To: Vlastimil Babka Cc: Nicolas Saenz Julienne , akpm@linux-foundation.org, frederic@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, tglx@linutronix.de, cl@linux.com, juri.lelli@redhat.com, mingo@redhat.com, mtosatti@redhat.com, nilal@redhat.com, mgorman@suse.de, ppandit@redhat.com, williams@redhat.com, bigeasy@linutronix.de, anna-maria@linutronix.de, linux-rt-users@vger.kernel.org Subject: Re: [PATCH 0/6] mm: Remote LRU per-cpu pagevec cache/per-cpu page list drain support Message-ID: <20210922112817.GO4323@worktop.programming.kicks-ass.net> References: <20210921161323.607817-1-nsaenzju@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 723AE12753BC X-Stat-Signature: maupg8yhj65ci6oz96hqqbjqw9h7hzyw Authentication-Results: imf13.hostedemail.com; dkim=pass header.d=infradead.org header.s=desiato.20200630 header.b=bpBVu4Ij; spf=none (imf13.hostedemail.com: domain of peterz@infradead.org has no SPF policy when checking 90.155.92.199) smtp.mailfrom=peterz@infradead.org; dmarc=none X-HE-Tag: 1632310101-379745 X-Bogosity: Ham, tests=bogofilter, spamicity=0.001950, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Sep 21, 2021 at 07:59:51PM +0200, Vlastimil Babka wrote: > These days the pcplist protection is done by local_lock, which solved > the RT concerns. Probably a stupid/infeasible idea, but maybe what you > want to achieve could be more generally solved at the local_lock level? > That on NOHZ_FULL CPUs, local_locks could have this mode where they > could synchronize with remote cpus? local_lock and spinlock have different rules, local_lock for example can never cause an irq inversion, unlike a spinlock.