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 65819C433EF for ; Wed, 19 Jan 2022 08:52:09 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C9AA26B0071; Wed, 19 Jan 2022 03:52:08 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id C4AAE6B0073; Wed, 19 Jan 2022 03:52:08 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B39056B0074; Wed, 19 Jan 2022 03:52:08 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0076.hostedemail.com [216.40.44.76]) by kanga.kvack.org (Postfix) with ESMTP id A5A586B0071 for ; Wed, 19 Jan 2022 03:52:08 -0500 (EST) Received: from smtpin21.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 6CDB88FD27 for ; Wed, 19 Jan 2022 08:52:08 +0000 (UTC) X-FDA: 79046419536.21.3B39299 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) by imf03.hostedemail.com (Postfix) with ESMTP id 194AD2000F for ; Wed, 19 Jan 2022 08:52:07 +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=vSg8ZrRKcNP4N0aIzqMy7pQZL/CJuOTJI8hGONUUDtQ=; b=V2TycFG+Wm8QFoNbKGqJZugqjM 1Z/iKER8MIhlqK0jrMVRqhoXQHdIiYhoAgTwKhWIAQ/VImr3fd8MSKzo24gMVfvHBHb4pFlboJ4IT Ud8iG6yGODjvdbjhY+hZ50qMyXzpvNcgj30IajhEKZmecCs2ooWezk2wWjmPJeRXRfSLBq8DnesB1 IN7r/3u57hdbSAdELOnYmSWwma5Dh8Njjd08USCJwcJLRybsOnrEHTCDxeLsw1NpvushX5trcICSO D+q/ihq2/VFGbfekiz76rEK0Scb/gSBdDLttwQKzcz7fCZ6//kQLVkwXJDhQCpDiguasLFPW7VMRG nXvQlkdA==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1nA6hB-0020SX-V1; Wed, 19 Jan 2022 08:51:58 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 8B880300140; Wed, 19 Jan 2022 09:51:57 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 6D1F829A40F04; Wed, 19 Jan 2022 09:51:57 +0100 (CET) Date: Wed, 19 Jan 2022 09:51:57 +0100 From: Peter Zijlstra To: Peter Oskolkov Cc: Peter Oskolkov , mingo@redhat.com, tglx@linutronix.de, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-api@vger.kernel.org, x86@kernel.org, pjt@google.com, avagin@google.com, jannh@google.com, tdelisle@uwaterloo.ca Subject: Re: [RFC][PATCH 3/3] sched: User Mode Concurency Groups Message-ID: References: <20211214204445.665580974@infradead.org> <20211214205358.701701555@infradead.org> <20211221171900.GA580323@dev-hv> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 194AD2000F X-Stat-Signature: 33n5or4th3rkteqf7r3w1dyqm7ex5o8o Authentication-Results: imf03.hostedemail.com; dkim=pass header.d=infradead.org header.s=desiato.20200630 header.b=V2TycFG+; dmarc=none; spf=none (imf03.hostedemail.com: domain of peterz@infradead.org has no SPF policy when checking 90.155.92.199) smtp.mailfrom=peterz@infradead.org X-HE-Tag: 1642582327-179172 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, Jan 18, 2022 at 10:19:21AM -0800, Peter Oskolkov wrote: > ================ worker timeouts > > Timeouts now are easy to explain: mutex::lock() and condvar::wait() have > timeouts, so workers waiting on these primitives naturally wait with timeouts; > if sys_umcg_wait() supports worker timeouts, this is it, all is simple; if > it does not, the userspace now has to implement the whole timeout machinery, > in order to wake these sleeping workers when their timeouts expire. I still have absolutely no idea what you're on about here. Please reply to the email on that subject: https://lkml.kernel.org/r/Ya34S2JCQg+81h4t@hirez.programming.kicks-ass.net What would you have the timeout actually do? Talk about the state transitions.