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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 1C05FC43331 for ; Fri, 22 Jan 2021 17:31:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D355A22DBF for ; Fri, 22 Jan 2021 17:31:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729766AbhAVR3K (ORCPT ); Fri, 22 Jan 2021 12:29:10 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55170 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729677AbhAVQym (ORCPT ); Fri, 22 Jan 2021 11:54:42 -0500 Received: from merlin.infradead.org (merlin.infradead.org [IPv6:2001:8b0:10b:1231::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 717F2C0613D6 for ; Fri, 22 Jan 2021 08:53:56 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.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=v3cTsSAtb1g200zNB0IkZQE4PzGibeoCJUAHIzGFIMo=; b=VrFtiLFTZvjYn3fhjhxA+XbF4U f9q50+3EXscgQv8qKheTxmxmMJuJK+7WtgWeRW4PJlUoIhNy+jXFmGv17Cy0Mk0F8IDhAJZs+sg4+ LTLeCMRRmGwQQUgGSsscU7Qk7feGVtvEXlr9Kbcxo1RydqG1RCcwCRVIiOasfNFmfVbkNUhg0xepw M4mkpcBiYAD+WY6kS6NVK+vV3E4lDumBQV8yY22PnQueHZz7L6zz+Na5AA1GFyOakfdRIoV9eigqH J72Nai1q8e9NtEIYxvMiDyCNzwh85eBlr7JS48kQJSCHMYYqT0IyuVwDU3Qpdc7GniFUWdjJR/pRC 7y+WMUfA==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=worktop.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1l2zgv-0000Uf-V1; Fri, 22 Jan 2021 16:53:46 +0000 Received: by worktop.programming.kicks-ass.net (Postfix, from userid 1000) id EE2509842C2; Fri, 22 Jan 2021 17:53:43 +0100 (CET) Date: Fri, 22 Jan 2021 17:53:43 +0100 From: Peter Zijlstra To: Frederic Weisbecker Cc: LKML , Michal Hocko , Mel Gorman , Thomas Gleixner , "Paul E . McKenney" , Ingo Molnar , Michal Hocko , ardb@kernel.org, jpoimboe@redhat.com Subject: Re: [RFC PATCH 4/8] preempt: Introduce CONFIG_PREEMPT_DYNAMIC Message-ID: <20210122165343.GE16371@worktop.programming.kicks-ass.net> References: <20210118141223.123667-1-frederic@kernel.org> <20210118141223.123667-5-frederic@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210118141223.123667-5-frederic@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jan 18, 2021 at 03:12:19PM +0100, Frederic Weisbecker wrote: > +config HAVE_PREEMPT_DYNAMIC > + bool > + depends on HAVE_STATIC_CALL_INLINE I think we can relax this to HAVE_STATIC_CALL, using trampolines shouldn't be too bad, and that would put it in reach of arm64. > + depends on GENERIC_ENTRY > + help > + Select this if the architecture support boot time preempt setting > + on top of static calls. It is strongly advised to support inline > + static call to avoid any overhead.