Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758144Ab0HDCJQ (ORCPT ); Tue, 3 Aug 2010 22:09:16 -0400 Received: from ozlabs.org ([203.10.76.45]:56684 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758079Ab0HDCJK (ORCPT ); Tue, 3 Aug 2010 22:09:10 -0400 From: Rusty Russell To: Jeremy Fitzhardinge Subject: Re: [RFC PATCH] x86-64: software IRQ masking and handling Date: Wed, 4 Aug 2010 11:39:05 +0930 User-Agent: KMail/1.13.2 (Linux/2.6.32-24-generic; KDE/4.4.2; i686; ; ) Cc: Tejun Heo , Linus Torvalds , Ingo Molnar , Thomas Gleixner , "H. Peter Anvin" , Peter Zijlstra , "the arch/x86 maintainers" , lkml , Christoph Lameter , Steven Rostedt , Frederic Weisbecker References: <4C3A06E3.50402@kernel.org> <4C588C0C.1070702@goop.org> In-Reply-To: <4C588C0C.1070702@goop.org> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201008041139.06739.rusty@rustcorp.com.au> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 977 Lines: 19 On Wed, 4 Aug 2010 07:07:16 am Jeremy Fitzhardinge wrote: > Of course if it becomes core to the x86 architecture or the kernel > overall, then most of the irq-related paravirt-ops can go away and be > limited to the actual interrupt handler and the machinery needed to > really mask/unmask the hardware and set the pending flag (which would > likely just be contained within the hypervisor-specific code, and not > need any new kernel interfaces to replace the dropped paravirt irq ones). Yep, we sweat over the cli/sti paravirtual implementations because it's so common. If the kernel used soft cli/sti we could simply implement it with a hypercall and be much happier (though iret possibly still an issue). Cheers, Rusty. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/