Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753485AbbG0Moj (ORCPT ); Mon, 27 Jul 2015 08:44:39 -0400 Received: from smtp.citrix.com ([66.165.176.89]:47925 "EHLO SMTP.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751347AbbG0Moi (ORCPT ); Mon, 27 Jul 2015 08:44:38 -0400 X-IronPort-AV: E=Sophos;i="5.15,553,1432598400"; d="scan'208";a="284681270" Message-ID: <55B62782.9050701@citrix.com> Date: Mon, 27 Jul 2015 13:43:46 +0100 From: Julien Grall User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Icedove/31.7.0 MIME-Version: 1.0 To: David Vrabel , CC: , , , Catalin Marinas , Will Deacon , , Ingo Molnar , "H. Peter Anvin" , Boris Ostrovsky , "Thomas Gleixner" , Subject: Re: [Xen-devel] [PATCH v2] xen/events: Support event channel rebind on ARM References: <1437996911-18985-1-git-send-email-julien.grall@citrix.com> <55B62588.3050502@citrix.com> In-Reply-To: <55B62588.3050502@citrix.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 8bit X-DLP: MIA2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2453 Lines: 66 On 27/07/15 13:35, David Vrabel wrote: > On 27/07/15 12:35, Julien Grall wrote: >> Currently, the event channel rebind code is gated with the presence of >> the vector callback. >> >> The virtual interrupt controller on ARM has the concept of per-CPU >> interrupt (PPI) which allow us to support per-VCPU event channel. >> Therefore there is no need of vector callback for ARM. >> >> Xen is already using a free PPI to notify the guest VCPU of an event. >> Furthermore, the xen code initialization in Linux (see >> arch/arm/xen/enlighten.c) is requesting correctly a per-CPU IRQ. >> >> Introduce new helper xen_support_evtchn_rebind to allow architecture >> decide whether rebind an event is support or not. It will always return >> 1 on ARM and keep the same behavior on x86. >> >> This is also allow us to drop the usage of xen_have_vector_callback >> entirely in the ARM code. > > This did not apply cleanly. Please always base patches on Linus's > master branch. My patch is based on Linus's master branch. Although, it has a pre-requisite of [1] which I sent a few seconds before it. Though it's only for applying because the 2 patches are not related. I should have mentioned it in the mail, sorry. > This also breaks the x86 build. I forgot to test this new version when I turned the macro into a static inline. > /local/davidvr/work/k.org/tip/arch/x86/include/asm/xen/events.h: In > function ?xen_support_evtchn_rebind?: > /local/davidvr/work/k.org/tip/arch/x86/include/asm/xen/events.h:29:85: > error: ?xen_have_vector_callback? undeclared (first use in this function) > return (!xen_hvm_domain() || xen_have_vector_callback); > >> --- a/arch/arm/include/asm/xen/events.h >> +++ b/arch/arm/include/asm/xen/events.h >> @@ -20,4 +20,10 @@ static inline int xen_irqs_disabled(struct pt_regs *regs) >> atomic64_t, \ >> counter), (val)) >> >> +/* Rebind event channel is supported by default */ >> +static inline bool xen_support_evtchn_rebind(void) >> +{ >> + return 1; > > This should be true (similarly for arm64). Will resend a new version, and remove the dependency on [1]. Regards, [1] http://permalink.gmane.org/gmane.linux.kernel/2004690 -- Julien Grall -- 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/