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=-0.8 required=3.0 tests=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 A28B8C47255 for ; Mon, 11 May 2020 14:36:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6FA0C206D6 for ; Mon, 11 May 2020 14:36:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729898AbgEKOgc (ORCPT ); Mon, 11 May 2020 10:36:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40588 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1727820AbgEKOgc (ORCPT ); Mon, 11 May 2020 10:36:32 -0400 Received: from Galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4C077C061A0C for ; Mon, 11 May 2020 07:36:31 -0700 (PDT) Received: from p5de0bf0b.dip0.t-ipconnect.de ([93.224.191.11] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1jY9X7-0008BQ-AC; Mon, 11 May 2020 16:35:53 +0200 Received: by nanos.tec.linutronix.de (Postfix, from userid 1000) id 6510FFFBF8; Mon, 11 May 2020 16:35:52 +0200 (CEST) From: Thomas Gleixner To: Lai Jiangshan Cc: LKML , x86@kernel.org, "Paul E. McKenney" , Andy Lutomirski , Alexandre Chartre , Frederic Weisbecker , Paolo Bonzini , Sean Christopherson , Masami Hiramatsu , Petr Mladek , Steven Rostedt , Joel Fernandes , Boris Ostrovsky , Juergen Gross , Brian Gerst , Mathieu Desnoyers , Josh Poimboeuf , Will Deacon Subject: Re: [patch V4 part 5 13/31] x86/irq: Convey vector as argument and not in ptregs In-Reply-To: References: <20200505135341.730586321@linutronix.de> <20200505135829.384803459@linutronix.de> Date: Mon, 11 May 2020 16:35:52 +0200 Message-ID: <87v9l25yk7.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Lai, Lai Jiangshan writes: > On Tue, May 5, 2020 at 10:23 PM Thomas Gleixner wrote: >> +SYM_CODE_START(irq_entries_start) >> + vector=FIRST_EXTERNAL_VECTOR >> + .rept (FIRST_SYSTEM_VECTOR - FIRST_EXTERNAL_VECTOR) >> + UNWIND_HINT_IRET_REGS >> + .byte 0x6a, vector >> + jmp common_interrupt >> + .align 8 >> + vector=vector+1 >> + .endr >> +SYM_CODE_END(irq_entries_start) > > Using ".byte 0x6a, vector" is somewhat ugly. > > I hope it should be " pushq $(s8_to_s64(vector))", which can also > help to reduce bunches of comments about ".byte 0x6a, vector". > > However, I don't know how to implement s8_to_s64() here. Neither do I. > But at least the following code works (generates the same two-byte > machine code as ".byte 0x6a, vector" does): > > .if vector < 128 > pushq $(vector) > .else > pushq $(0xffffffffffffff00+vector) > .endif Only slightly less ugly and needs as much commentry as the above. Thanks, tglx