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=-2.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT autolearn=ham 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 F2591C43441 for ; Mon, 12 Nov 2018 08:56:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B8EF3223C6 for ; Mon, 12 Nov 2018 08:56:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="as6pH9A9" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B8EF3223C6 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728613AbeKLStG (ORCPT ); Mon, 12 Nov 2018 13:49:06 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:34580 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727208AbeKLStF (ORCPT ); Mon, 12 Nov 2018 13:49:05 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.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:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=hnuroTyDW2i5GN4XkKKngIjHBnLFpctUGkvwhs7Hyrg=; b=as6pH9A9yTcM3DRNzSQr9FmeX +w8c5MY8lJlTNWSEE6Qv02XgOlv9Cgx4A5CPUQdsxUg6pEoTp5rAJGRPqaKpgpwz3H/q5Pzg/8LP/ PrQi5W2R1wEGFhVpR+xG0uJLKWIRlb+CwZ+INzygPrwXMRwRGfy9hvAcR+3m4NVICLjtI8B5zdY2M tmTNCqr1N5exLE8oSjSzfMd0fqk0VBeu68YUrWyVQqzl2Vi1/LwvTfoZI+gsSbPTUpkxF5O3ccmZd JUH5ARZU5jJg7ycCdmPsBqkQHnEQQnz732NUJKYTlJ3VWrgvHONNuJuCopgae5R3EAfkNFU++uYfV XnY+kwDSw==; Received: from [64.114.255.114] (helo=worktop) by bombadil.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1gM81a-0007i6-QD; Mon, 12 Nov 2018 08:56:50 +0000 Received: by worktop (Postfix, from userid 1000) id 130126E03B0; Mon, 12 Nov 2018 09:56:50 +0100 (CET) Date: Mon, 12 Nov 2018 09:56:50 +0100 From: Peter Zijlstra To: Ingo Molnar Cc: Aubrey Li , tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, ak@linux.intel.com, tim.c.chen@linux.intel.com, arjan@linux.intel.com, linux-kernel@vger.kernel.org, Aubrey Li Subject: Re: [RFC PATCH v1 2/2] proc: add /proc//thread_state Message-ID: <20181112085650.GM3056@worktop> References: <1541528590-30296-1-git-send-email-aubrey.li@intel.com> <1541528590-30296-2-git-send-email-aubrey.li@intel.com> <20181108063246.GA13233@gmail.com> <20181108101729.GP9761@hirez.programming.kicks-ass.net> <20181112053147.GA78520@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181112053147.GA78520@gmail.com> User-Agent: Mutt/1.5.22.1 (2013-10-16) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 12, 2018 at 06:31:47AM +0100, Ingo Molnar wrote: > > * Peter Zijlstra wrote: > > > On Thu, Nov 08, 2018 at 07:32:46AM +0100, Ingo Molnar wrote: > > > > > > * Aubrey Li wrote: > > > > > > > Expose the per-task cpu specific thread state value, it's helpful > > > > for userland to classify and schedule the tasks by different policies > > > > > > That's pretty vague - what exactly would use this information? I'm sure > > > you have a usecase in mind - could you please describe it? > > > > Yeah, "thread_state" is a pretty terrible name for this. The use-case is > > detectoring which tasks use AVX3 such that a userspace component (think > > job scheduler) can cluster them together. > > I'd prefer the kernel to do such clustering... I think that is a next step. Also, while the kernel can do this at a best effort basis, it cannot take into account things the kernel doesn't know about, like high priority job peak load etc.., things a job scheduler would know. Then again, a job scheduler would likely already know about the AVX state anyway.