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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6275FC433F5 for ; Wed, 9 Feb 2022 13:00:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233789AbiBINAn (ORCPT ); Wed, 9 Feb 2022 08:00:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38224 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231244AbiBINAl (ORCPT ); Wed, 9 Feb 2022 08:00:41 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7CDC7C0613CA; Wed, 9 Feb 2022 05:00:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.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; bh=WsOEfwHfdGK6OlGgVv/+90ZBfy4NMObfd2hptU6CEbw=; b=eBpZPsGk3XwEinAbJReC/9MJNC 2cV45KnaMNFbX8Nqpgn9nXiQr8p8XcLefLEC+//XtVUO6tkbep1gjagjB64y+npGRpuGagRaGCmBr EFaXMMaJO2UKQZnA7aN/nyhLnhjBXi7W50WPpnR3/94GY3fjDRILwAdw3CA2jMzTaHFfMVBJR8iRq Pfx6627C5k1QbjV0WFayjVyysh+7vYE9W0vkrNvWhvpfwLDvMSkEcMNXLn/PmgghfI7PVsgZrx/rb AoGa1AYHpH6EPergMeDtyvoLVMdCAeU2XJYEK5G/XJ8jpReWdWRqx4apf2DVuIe7/9xCnwxiADZU/ g6fyDIvQ==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1nHmaJ-007jI7-6Z; Wed, 09 Feb 2022 13:00:35 +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 A1D99300478; Wed, 9 Feb 2022 14:00:34 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 8B30D265018D6; Wed, 9 Feb 2022 14:00:34 +0100 (CET) Date: Wed, 9 Feb 2022 14:00:34 +0100 From: Peter Zijlstra To: Adrian Hunter Cc: Alexander Shishkin , Arnaldo Carvalho de Melo , Jiri Olsa , linux-kernel@vger.kernel.org, Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, kvm@vger.kernel.org, H Peter Anvin , Mathieu Poirier , Suzuki K Poulose , Leo Yan Subject: Re: [PATCH 03/11] perf/x86: Add support for TSC in nanoseconds as a perf event clock Message-ID: References: <20220209084929.54331-1-adrian.hunter@intel.com> <20220209084929.54331-4-adrian.hunter@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220209084929.54331-4-adrian.hunter@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Feb 09, 2022 at 10:49:21AM +0200, Adrian Hunter wrote: > + if (sched_clock_stable()) { > + offset = __sched_clock_offset; The only sane behviour for !sched_clock_stable() is to completely refuse service.