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 C98B6ECAAA1 for ; Tue, 30 Aug 2022 18:59:37 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 194348D0002; Tue, 30 Aug 2022 14:59:37 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 11C808D0001; Tue, 30 Aug 2022 14:59:37 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id ED9248D0002; Tue, 30 Aug 2022 14:59:36 -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 D94AE8D0001 for ; Tue, 30 Aug 2022 14:59:36 -0400 (EDT) Received: from smtpin24.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 9E3231A05AE for ; Tue, 30 Aug 2022 18:59:36 +0000 (UTC) X-FDA: 79857172752.24.1BE3298 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by imf27.hostedemail.com (Postfix) with ESMTP id 21B0140071 for ; Tue, 30 Aug 2022 18:59:35 +0000 (UTC) Date: Tue, 30 Aug 2022 20:59:32 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1661885974; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=30hwmgNyab1o6UAoaSXl7ThhaGzoswkIVJZDDP581Tg=; b=iUIan095w7Sk0bxx8quXKIktV6pmOk2W93WIbOKcHCQaWKbFQNsJUL7tkOQdtzOW3L2RNg WtzgisD/H6Du/EQa6x3xmvTqjuYDESdJlNgliR8J215aYfrTQswENysVfbDt72/ZHKc9jZ C6WXjZmwrGkDUQaRkSwv8T4OhM5fELDKviOChlGsACKEIr/P/zow3G47egUYqkHAD5so6I Rcrhmq2SG60btMpFnmyoogEwEhvMqxugpoKxQv5n0FnuLKXhiRik+qHG8cTsXsRAvBkxPz xa3sHd7WCs4Q8/juMxZJ4XiJA+ZRbIebzhR5F/kKnZ2bXQx0blvr5rzpLfiZQA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1661885974; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=30hwmgNyab1o6UAoaSXl7ThhaGzoswkIVJZDDP581Tg=; b=GjPVsF1PokOV1x3eVcXX7bNwS8YjTnNRrRHgHawjZ0v01fKgNn1V9EopdVfhl1JFYIA206 Quq2l0nFZjC0oHBw== From: Sebastian Andrzej Siewior To: Maurizio Lombardi Cc: Vlastimil Babka , linux-mm , David Rientjes , Pekka Enberg , Joonsoo Kim , Andrew Morton , LKML , tglx@linutronix.de Subject: Re: [PATCH RFC] mm: slub: fix flush_cpu_slab()/__free_slab() invocations in task context. Message-ID: References: <20220829154805.1205507-1-mlombard@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: ARC-Authentication-Results: i=1; imf27.hostedemail.com; dkim=pass header.d=linutronix.de header.s=2020 header.b=iUIan095; dkim=pass header.d=linutronix.de header.s=2020e header.b=GjPVsF1P; spf=pass (imf27.hostedemail.com: domain of bigeasy@linutronix.de designates 193.142.43.55 as permitted sender) smtp.mailfrom=bigeasy@linutronix.de; dmarc=pass (policy=none) header.from=linutronix.de ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1661885976; a=rsa-sha256; cv=none; b=Kg02xEnanazHZj59GX5+QUqTTLStgur+CHZ9bnREA2V640rihpBJFtSYX9Grw5Uma9e7y8 xWP4iTwY6agPA1vkFCBUxnRdAyKJ/L+jHR7/WG33rAmmdu2vZKO/C0DsOBNJ5h6OQDcwFk OGVuhb50FY9h1fqzyPtN0KgKqhLPcaM= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1661885976; 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=30hwmgNyab1o6UAoaSXl7ThhaGzoswkIVJZDDP581Tg=; b=pJTGf/qfnP2obCbbh7XyS3LP7bRuSRLvSmL7irWaLrH4wAVHBoIwhBV2yk6GHUUTecxkT6 pn66dp1BhXFBBASHC9BTy3pzR6ZFY/yUQ3EYbFQu8rsT4nhN37qPpKBY509t5/WBuEUBT/ 5mAoB8VbGcarvsBhikc1B4Oq2wl9wPc= X-Rspam-User: Authentication-Results: imf27.hostedemail.com; dkim=pass header.d=linutronix.de header.s=2020 header.b=iUIan095; dkim=pass header.d=linutronix.de header.s=2020e header.b=GjPVsF1P; spf=pass (imf27.hostedemail.com: domain of bigeasy@linutronix.de designates 193.142.43.55 as permitted sender) smtp.mailfrom=bigeasy@linutronix.de; dmarc=pass (policy=none) header.from=linutronix.de X-Rspamd-Server: rspam02 X-Stat-Signature: 8d3ac5ys3c88ox7u7aagjqhsp1jfbcnb X-Rspamd-Queue-Id: 21B0140071 X-HE-Tag: 1661885975-583626 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 2022-08-30 17:48:06 [+0200], Maurizio Lombardi wrote: > Hmm, this is not good indeed. I guess I should have used for_each_online_cpu() > instead of on_each_cpu_cond(). But you must not invoked that function cross-CPU since the code expects to access the per-CPU variables always from the local-CPU. > > > > Couldn't we instead use a workqueue with that WQ_MEM_RECLAIM bit? It may > > reclaim memory after all ;) > > That should also fix it, do you think it would be ok to allocate a workqueue in > in kmem_cache_init() ? I guess so. There is probably none that is already available. > Thanks, > Maurizio Sebastian