From patchwork Thu May 5 08:07:29 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ingo Molnar X-Patchwork-Id: 756222 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter2.kernel.org (8.14.4/8.14.3) with ESMTP id p4587jKm014649 for ; Thu, 5 May 2011 08:07:45 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752334Ab1EEIHm (ORCPT ); Thu, 5 May 2011 04:07:42 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:52035 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751473Ab1EEIHk (ORCPT ); Thu, 5 May 2011 04:07:40 -0400 Received: from elvis.elte.hu ([157.181.1.14]) by mx2.mail.elte.hu with esmtp (Exim) id 1QHtas-0006bJ-WC from ; Thu, 05 May 2011 10:07:38 +0200 Received: by elvis.elte.hu (Postfix, from userid 1004) id 800583E2526; Thu, 5 May 2011 10:07:25 +0200 (CEST) Date: Thu, 5 May 2011 10:07:29 +0200 From: Ingo Molnar To: Pekka Enberg Cc: Asias He , Sasha Levin , gorcunov@gmail.com, prasadjoshi124@gmail.com, kvm@vger.kernel.org Subject: Re: [PATCH 2/2 V2] kvm tools: Fix virt_queue__set_used_elem Message-ID: <20110505080729.GD14391@elte.hu> References: <1304454487-2539-1-git-send-email-levinsasha928@gmail.com> <1304454487-2539-2-git-send-email-levinsasha928@gmail.com> <20110503204716.GA27887@elte.hu> <1304484063.13143.9.camel@lappy> <4DC1E57B.3060809@gmail.com> <20110505070211.GA13043@elte.hu> <20110505074716.GC14391@elte.hu> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-08-17) Received-SPF: neutral (mx2.mail.elte.hu: 157.181.1.14 is neither permitted nor denied by domain of elte.hu) client-ip=157.181.1.14; envelope-from=mingo@elte.hu; helo=elvis.elte.hu; X-ELTE-SpamScore: -2.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.0 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.3.1 -2.0 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter2.kernel.org [140.211.167.43]); Thu, 05 May 2011 08:07:45 +0000 (UTC) * Pekka Enberg wrote: > > asm/system.h is one of the messier kernel headers, so i'm not surprised it > > has assymetric requirements on 64-bit and 32-bit systems. > > So does including before fix the problem > on 32-bit boxes? [...] No, it's more complex than that. > [...] If so, I'd prefer we fix it like that for now. The patch below sorts out the dependencies and makes it build on both 64-bit and 32-bit systems. (I have not runtime tested the result though.) I'm not entirely happy about how it has added dependent includes to virtio.c but that's a property of this messy header file. Might be worth adding a comment about that. Thanks, Ingo -----------------> From 51cb9390753c0bb333896fbc951cc53bcae2723d Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Thu, 5 May 2011 10:00:45 +0200 Subject: [PATCH] kvm: Fix 32-bit build of the asm/system.h include Provide wrappers and other environmental dependencies that the asm/system.h header file from hell needs to build fine in user-space. Sidenote: right now alternative() defaults to the compatible, slightly slower barrier instructions that work on all x86 systems. If this ever shows up in profiles then kvm could provide an alternatives patching machinery as well. Right now those instructions are emitted into special sections and then discarded by the linker harmlessly. Signed-off-by: Ingo Molnar --- tools/kvm/include/asm/hweight.h | 8 ++++++++ tools/kvm/include/linux/bitops.h | 33 +++++++++++++++++++++++++++++++++ tools/kvm/virtio.c | 5 +++++ 3 files changed, 46 insertions(+), 0 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/tools/kvm/include/asm/hweight.h b/tools/kvm/include/asm/hweight.h new file mode 100644 index 0000000..36cf26d --- /dev/null +++ b/tools/kvm/include/asm/hweight.h @@ -0,0 +1,8 @@ +#ifndef PERF_HWEIGHT_H +#define PERF_HWEIGHT_H + +#include +unsigned int hweight32(unsigned int w); +unsigned long hweight64(__u64 w); + +#endif /* PERF_HWEIGHT_H */ diff --git a/tools/kvm/include/linux/bitops.h b/tools/kvm/include/linux/bitops.h new file mode 100644 index 0000000..305c848 --- /dev/null +++ b/tools/kvm/include/linux/bitops.h @@ -0,0 +1,33 @@ +#ifndef _PERF_LINUX_BITOPS_H_ +#define _PERF_LINUX_BITOPS_H_ + +#include +#include +#include + +#define BITS_PER_LONG __WORDSIZE +#define BITS_PER_BYTE 8 +#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long)) + +static inline void set_bit(int nr, unsigned long *addr) +{ + addr[nr / BITS_PER_LONG] |= 1UL << (nr % BITS_PER_LONG); +} + +static inline void clear_bit(int nr, unsigned long *addr) +{ + addr[nr / BITS_PER_LONG] &= ~(1UL << (nr % BITS_PER_LONG)); +} + +static __always_inline int test_bit(unsigned int nr, const unsigned long *addr) +{ + return ((1UL << (nr % BITS_PER_LONG)) & + (((unsigned long *)addr)[nr / BITS_PER_LONG])) != 0; +} + +static inline unsigned long hweight_long(unsigned long w) +{ + return sizeof(w) == 4 ? hweight32(w) : hweight64(w); +} + +#endif diff --git a/tools/kvm/virtio.c b/tools/kvm/virtio.c index 266a1b6..3a4b1c9 100644 --- a/tools/kvm/virtio.c +++ b/tools/kvm/virtio.c @@ -1,7 +1,12 @@ #include #include #include + +#include +#include +#include #include + #include "kvm/kvm.h" #include "kvm/virtio.h"