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,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 6674BC43387 for ; Mon, 17 Dec 2018 16:37:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 375B82145D for ; Mon, 17 Dec 2018 16:37:39 +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="dQXzUi5N" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388170AbeLQQhi (ORCPT ); Mon, 17 Dec 2018 11:37:38 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:60048 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387833AbeLQQhi (ORCPT ); Mon, 17 Dec 2018 11:37:38 -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=tvRn8uif1FnxMDVH2moPVASXN2XAW1fiY/rFaMZFEyI=; b=dQXzUi5NrkierFSHvM7QCXs/O ZWFNmaeehaYNLpnR9GzryAAPBBuVRKGb5l5VBNg47EzvcT89POWv2REMMhC0649KvhmagRsJd1tAe CWc/ezl7zDP9exWBlWQqVDFjwSShk2d317FMyVCXlrY+5VwqB0lgpwGiPAS2S7juxUN90QpPCo335 w1nOWDyeWHwjeWfpfeglVR7q5ulW8OAr7kzgQwyk72FblOry58HlIPfwfLw+tOfINWShO3EXTyu9c 801sQ9YVHkOnYX7T5Py6gD59cwK0XaIHPSww5RXI6TDjy8JZFY5geZl+5MLUlQDc6vioOAhAuiKu1 po2hgPN8g==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1gYvtX-00011h-MH; Mon, 17 Dec 2018 16:37:27 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 8D56420276ABC; Mon, 17 Dec 2018 17:27:13 +0100 (CET) Date: Mon, 17 Dec 2018 17:27:13 +0100 From: Peter Zijlstra To: Suren Baghdasaryan Cc: gregkh@linuxfoundation.org, tj@kernel.org, lizefan@huawei.com, hannes@cmpxchg.org, axboe@kernel.dk, dennis@kernel.org, dennisszhou@gmail.com, mingo@redhat.com, akpm@linux-foundation.org, corbet@lwn.net, cgroups@vger.kernel.org, linux-mm@kvack.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@android.com Subject: Re: [PATCH 6/6] psi: introduce psi monitor Message-ID: <20181217162713.GE2218@hirez.programming.kicks-ass.net> References: <20181214171508.7791-1-surenb@google.com> <20181214171508.7791-7-surenb@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181214171508.7791-7-surenb@google.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 14, 2018 at 09:15:08AM -0800, Suren Baghdasaryan wrote: > @@ -358,28 +526,23 @@ static void psi_update_work(struct work_struct *work) > { > struct delayed_work *dwork; > struct psi_group *group; > + u64 next_update; > > dwork = to_delayed_work(work); > group = container_of(dwork, struct psi_group, clock_work); > > /* > + * Periodically fold the per-cpu times and feed samples > + * into the running averages. > */ > > + psi_update(group); > > + /* Calculate closest update time */ > + next_update = min(group->polling_next_update, > + group->avg_next_update); > + schedule_delayed_work(dwork, min(PSI_FREQ, > + nsecs_to_jiffies(next_update - sched_clock()) + 1)); See, so I don't at _all_ like how there is no idle option.. > }