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 F021DCE79AA for ; Tue, 19 Sep 2023 16:23:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231539AbjISQXH convert rfc822-to-8bit (ORCPT ); Tue, 19 Sep 2023 12:23:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44978 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230162AbjISQXE (ORCPT ); Tue, 19 Sep 2023 12:23:04 -0400 Received: from lithops.sigma-star.at (lithops.sigma-star.at [195.201.40.130]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 445FEB3; Tue, 19 Sep 2023 09:22:56 -0700 (PDT) Received: from localhost (localhost [127.0.0.1]) by lithops.sigma-star.at (Postfix) with ESMTP id 5074A635DB51; Tue, 19 Sep 2023 18:22:48 +0200 (CEST) Received: from lithops.sigma-star.at ([127.0.0.1]) by localhost (lithops.sigma-star.at [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id m6Ardn4BMmQu; Tue, 19 Sep 2023 18:22:47 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by lithops.sigma-star.at (Postfix) with ESMTP id 6D072622F591; Tue, 19 Sep 2023 18:22:47 +0200 (CEST) Received: from lithops.sigma-star.at ([127.0.0.1]) by localhost (lithops.sigma-star.at [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id rJmHKg4qnWLe; Tue, 19 Sep 2023 18:22:47 +0200 (CEST) Received: from lithops.sigma-star.at (lithops.sigma-star.at [195.201.40.130]) by lithops.sigma-star.at (Postfix) with ESMTP id 16951635DB51; Tue, 19 Sep 2023 18:22:47 +0200 (CEST) Date: Tue, 19 Sep 2023 18:22:46 +0200 (CEST) From: Richard Weinberger To: anton ivanov Cc: tglx , Peter Zijlstra , John Paul Adrian Glaubitz , Matthew Wilcox , torvalds , Ankur Arora , linux-kernel , linux-mm , x86 , Andrew Morton , Andy Lutomirski , bp , dave hansen , hpa , mingo , juri lelli , vincent guittot , mgorman@suse.de, Steven Rostedt , jon grimm , bharata@amd.com, raghavendra kt , boris ostrovsky , konrad wilk , jgross , andrew cooper3 , Geert Uytterhoeven , linux-m68k , Johannes Berg , linux-um , Brian Cain , linux-hexagon@vger.kernel.org, Richard Henderson , Ivan Kokshaysky , Matt Turner , linux-alpha Message-ID: <551475267.58816.1695140566849.JavaMail.zimbra@nod.at> In-Reply-To: <9a5c0856-d542-9912-7494-53d7fe4538a3@cambridgegreys.com> References: <87zg1u1h5t.fsf@oracle.com> <87led2wdj0.ffs@tglx> <0e69f7df80dc5878071deb0d80938138d19de1d1.camel@physik.fu-berlin.de> <20230919134218.GA39281@noisy.programming.kicks-ass.net> <87y1h2ur98.ffs@tglx> <9a5c0856-d542-9912-7494-53d7fe4538a3@cambridgegreys.com> Subject: Re: Arches that don't support PREEMPT MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT X-Originating-IP: [195.201.40.130] X-Mailer: Zimbra 8.8.12_GA_3807 (ZimbraWebClient - FF97 (Linux)/8.8.12_GA_3809) Thread-Topic: Arches that don't support PREEMPT Thread-Index: bIFTlUwZ+xXV2WWntYYwoPsb2f3c+g== Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ----- Ursprüngliche Mail ----- > Von: "anton ivanov" > It's been a while. I remember that I dropped it at the time, but do not remember > the full details. > > There was some stuff related to FP state and a few other issues I ran into while > rewriting the interrupt controller. Some of it may be resolved by now as we are > using host cpu flags, etc. I remember also having a hacky but working version almost 10 years ago. It was horrible slow because of the extra scheduler rounds. But yes, if PREEMPT will be a must-have feature we'll have to try again. Thanks, //richard