From patchwork Wed Oct 31 22:46:59 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marcelo Tosatti X-Patchwork-Id: 1682071 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork1.kernel.org (Postfix) with ESMTP id 7287A40060 for ; Wed, 31 Oct 2012 22:47:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933842Ab2JaWrK (ORCPT ); Wed, 31 Oct 2012 18:47:10 -0400 Received: from mx1.redhat.com ([209.132.183.28]:52685 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932667Ab2JaWrH (ORCPT ); Wed, 31 Oct 2012 18:47:07 -0400 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id q9VMkvce010711 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Wed, 31 Oct 2012 18:46:58 -0400 Received: from amt.cnet (vpn1-4-132.gru2.redhat.com [10.97.4.132]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id q9VMkvws012999; Wed, 31 Oct 2012 18:46:57 -0400 Received: from amt.cnet (amt.cnet [127.0.0.1]) by amt.cnet (Postfix) with ESMTP id 934B968A30A; Wed, 31 Oct 2012 20:46:02 -0200 (BRST) Received: (from marcelo@localhost) by amt.cnet (8.14.5/8.14.5/Submit) id q9VMk24e017056; Wed, 31 Oct 2012 20:46:02 -0200 Message-Id: <20121031224823.952962057@redhat.com> User-Agent: quilt/0.47-1 Date: Wed, 31 Oct 2012 20:46:59 -0200 From: Marcelo Tosatti To: kvm@vger.kernel.org Cc: johnstul@us.ibm.com, jeremy@goop.org, glommer@parallels.com, zamsden@gmail.com, gleb@redhat.com, avi@redhat.com, pbonzini@redhat.com, Marcelo Tosatti Subject: [patch 03/16] x86: pvclock: remove pvclock_shadow_time References: <20121031224656.417434866@redhat.com> Content-Disposition: inline; filename=02-pvclock-remove-shadow-time X-Scanned-By: MIMEDefang 2.68 on 10.5.11.23 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Originally from Jeremy Fitzhardinge. We can copy the information directly from "struct pvclock_vcpu_time_info", remove pvclock_shadow_time. Signed-off-by: Marcelo Tosatti Reviewed-by: Glauber Costa --- 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 Index: vsyscall/arch/x86/kernel/pvclock.c =================================================================== --- vsyscall.orig/arch/x86/kernel/pvclock.c +++ vsyscall/arch/x86/kernel/pvclock.c @@ -19,21 +19,6 @@ #include #include -/* - * These are perodically updated - * xen: magic shared_info page - * kvm: gpa registered via msr - * and then copied here. - */ -struct pvclock_shadow_time { - u64 tsc_timestamp; /* TSC at last update of time vals. */ - u64 system_timestamp; /* Time, in nanosecs, since boot. */ - u32 tsc_to_nsec_mul; - int tsc_shift; - u32 version; - u8 flags; -}; - static u8 valid_flags __read_mostly = 0; void pvclock_set_flags(u8 flags) @@ -41,32 +26,11 @@ void pvclock_set_flags(u8 flags) valid_flags = flags; } -static u64 pvclock_get_nsec_offset(struct pvclock_shadow_time *shadow) +static u64 pvclock_get_nsec_offset(const struct pvclock_vcpu_time_info *src) { - u64 delta = native_read_tsc() - shadow->tsc_timestamp; - return pvclock_scale_delta(delta, shadow->tsc_to_nsec_mul, - shadow->tsc_shift); -} - -/* - * Reads a consistent set of time-base values from hypervisor, - * into a shadow data area. - */ -static unsigned pvclock_get_time_values(struct pvclock_shadow_time *dst, - struct pvclock_vcpu_time_info *src) -{ - do { - dst->version = src->version; - rmb(); /* fetch version before data */ - dst->tsc_timestamp = src->tsc_timestamp; - dst->system_timestamp = src->system_time; - dst->tsc_to_nsec_mul = src->tsc_to_system_mul; - dst->tsc_shift = src->tsc_shift; - dst->flags = src->flags; - rmb(); /* test version after fetching data */ - } while ((src->version & 1) || (dst->version != src->version)); - - return dst->version; + u64 delta = native_read_tsc() - src->tsc_timestamp; + return pvclock_scale_delta(delta, src->tsc_to_system_mul, + src->tsc_shift); } unsigned long pvclock_tsc_khz(struct pvclock_vcpu_time_info *src) @@ -90,21 +54,22 @@ void pvclock_resume(void) cycle_t pvclock_clocksource_read(struct pvclock_vcpu_time_info *src) { - struct pvclock_shadow_time shadow; unsigned version; cycle_t ret, offset; u64 last; + u8 flags; do { - version = pvclock_get_time_values(&shadow, src); + version = src->version; rdtsc_barrier(); - offset = pvclock_get_nsec_offset(&shadow); - ret = shadow.system_timestamp + offset; + offset = pvclock_get_nsec_offset(src); + ret = src->system_time + offset; + flags = src->flags; rdtsc_barrier(); - } while (version != src->version); + } while ((src->version & 1) || version != src->version); if ((valid_flags & PVCLOCK_TSC_STABLE_BIT) && - (shadow.flags & PVCLOCK_TSC_STABLE_BIT)) + (flags & PVCLOCK_TSC_STABLE_BIT)) return ret; /*