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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 44876C43381 for ; Thu, 14 Jan 2021 16:17:21 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id C3D2623B2F for ; Thu, 14 Jan 2021 16:17:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C3D2623B2F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linutronix.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id F114E6B007B; Thu, 14 Jan 2021 11:17:10 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id E53736B0098; Thu, 14 Jan 2021 11:17:10 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D148F6B007B; Thu, 14 Jan 2021 11:17:10 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0110.hostedemail.com [216.40.44.110]) by kanga.kvack.org (Postfix) with ESMTP id BCB456B005D for ; Thu, 14 Jan 2021 11:17:10 -0500 (EST) Received: from smtpin23.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 86A5B2C04 for ; Thu, 14 Jan 2021 16:17:10 +0000 (UTC) X-FDA: 77704885020.23.force97_0a0ad9627528 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin23.hostedemail.com (Postfix) with ESMTP id 5762D37609 for ; Thu, 14 Jan 2021 16:17:10 +0000 (UTC) X-HE-Tag: force97_0a0ad9627528 X-Filterd-Recvd-Size: 2595 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by imf39.hostedemail.com (Postfix) with ESMTP for ; Thu, 14 Jan 2021 16:17:09 +0000 (UTC) Date: Thu, 14 Jan 2021 17:17:07 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1610641027; 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=eqtQbeVMLh79dOF34C4Z4RZ/eHRYm7fDBoO+wUdjOFQ=; b=H8UGuXTZY8e5lYl9xfmE2yteNTRFFfth5mjlr/Ufxfetg1nZS8slBsgHiY2EyxBa9ZpxQ3 NQ1R3i4GgYwl6aK7WydMzkJOdRUmKELLwLbOJCVznBuNI+Tq0juiIH06Xi7Y6tEHiucenh eGpec0HqahCXrdd3avVF/xfQTymqJEyMU+681H4QVZimiZXSpfJ1basSmL0kyQ6Y0QWO0y 6ukJEfjJKgz3OxQ6LVb2kNfcXCulKvBPxnWEmT7mXJ8c0XSMQR2ijW2s3WZnTNwp4d0kNO Lr7vs0l6BlfqmWj2e7vxIOR5JFqPserGl7RrRoQ4k1KgWxkEAmjM8GasS1Q0CQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1610641027; 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=eqtQbeVMLh79dOF34C4Z4RZ/eHRYm7fDBoO+wUdjOFQ=; b=0zWEAw9zSfSoVi7BljSvsSx8knAavkNmAiL37X3TW1M99P9EFCXdWmPc/xAyZRKMuSm/x1 OLSGwSFG9DY3XiBw== From: Sebastian Andrzej Siewior To: Vitaly Wool Cc: Matthew Wilcox , Mike Galbraith , LKML , linux-mm , Barry Song , Minchan Kim , NitinGupta Subject: Re: [PATCH] zsmalloc: do not use bit_spin_lock Message-ID: <20210114161707.wfgbxi2rppoobfo7@linutronix.de> References: <18669bd607ae9efbf4e00e36532c7aa167d0fa12.camel@gmx.de> <20201220002228.38697-1-vitaly.wool@konsulko.com> <20201220011835.GU15600@casper.infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: 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 2020-12-20 08:21:37 [+0100], Vitaly Wool wrote: > Not really because bit spinlock leaves preemption disabled. It leaves it disabled for a reason. Now you just spin until the original context gets back on the CPU. On UP with preemption, if the "lock owner" gets preempted, the next lock attempt will lock-up the system. Sebastian