Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753250AbdHBO7G (ORCPT ); Wed, 2 Aug 2017 10:59:06 -0400 Received: from mailhub.sw.ru ([195.214.232.25]:36714 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752433AbdHBO7F (ORCPT ); Wed, 2 Aug 2017 10:59:05 -0400 From: Denis Plotnikov To: pbonzini@redhat.com, rkrcmar@redhat.com, kvm@vger.kernel.org, john.stultz@linaro.org, tglx@linutronix.de Cc: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, x86@kernel.org, rkagan@virtuozzo.com, den@virtuozzo.com Subject: [PATCH v4 08/10] pvclock: add parameters to store stamp data in pvclock reading function Date: Wed, 2 Aug 2017 17:38:08 +0300 Message-Id: <1501684690-211093-9-git-send-email-dplotnikov@virtuozzo.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1501684690-211093-1-git-send-email-dplotnikov@virtuozzo.com> References: <1501684690-211093-1-git-send-email-dplotnikov@virtuozzo.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3613 Lines: 105 The parameters is a pointer which is used to store cycles and flags stamp value used for time calulation on pvclock reading. This is a part of the work aiming to make possible to use KVM masterclock in L2 guests (those once running over kvmclock clocksource). Signed-off-by: Denis Plotnikov --- arch/x86/include/asm/pvclock.h | 3 ++- arch/x86/kernel/kvmclock.c | 2 +- arch/x86/kernel/pvclock.c | 18 +++++++++++++++--- arch/x86/xen/time.c | 2 +- 4 files changed, 19 insertions(+), 6 deletions(-) diff --git a/arch/x86/include/asm/pvclock.h b/arch/x86/include/asm/pvclock.h index 448cfe1..f4ff2c0 100644 --- a/arch/x86/include/asm/pvclock.h +++ b/arch/x86/include/asm/pvclock.h @@ -14,7 +14,8 @@ static inline struct pvclock_vsyscall_time_info *pvclock_pvti_cpu0_va(void) #endif /* some helper functions for xen and kvm pv clock sources */ -u64 pvclock_clocksource_read(struct pvclock_vcpu_time_info *src); +u64 pvclock_clocksource_read(struct pvclock_vcpu_time_info *src, + u64 *cycles_stamp, u8 *flags_stamp); u8 pvclock_read_flags(struct pvclock_vcpu_time_info *src); void pvclock_set_flags(u8 flags); unsigned long pvclock_tsc_khz(struct pvclock_vcpu_time_info *src); diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c index d889676..f692579 100644 --- a/arch/x86/kernel/kvmclock.c +++ b/arch/x86/kernel/kvmclock.c @@ -91,7 +91,7 @@ static u64 kvm_clock_read(void) preempt_disable_notrace(); cpu = smp_processor_id(); src = &hv_clock[cpu].pvti; - ret = pvclock_clocksource_read(src); + ret = pvclock_clocksource_read(src, NULL, NULL); preempt_enable_notrace(); return ret; } diff --git a/arch/x86/kernel/pvclock.c b/arch/x86/kernel/pvclock.c index 5c3f6d6..bece384 100644 --- a/arch/x86/kernel/pvclock.c +++ b/arch/x86/kernel/pvclock.c @@ -73,21 +73,32 @@ u8 pvclock_read_flags(struct pvclock_vcpu_time_info *src) return flags & valid_flags; } -u64 pvclock_clocksource_read(struct pvclock_vcpu_time_info *src) +u64 pvclock_clocksource_read(struct pvclock_vcpu_time_info *src, + u64 *cycles_stamp, u8 *flags_stamp) { unsigned version; u64 ret; u64 last; u8 flags; + u64 tsc; do { version = pvclock_read_begin(src); - ret = __pvclock_read_cycles(src, rdtsc_ordered()); + tsc = rdtsc_ordered(); + ret = __pvclock_read_cycles(src, tsc); flags = src->flags; } while (pvclock_read_retry(src, version)); + if (cycles_stamp) + *cycles_stamp = tsc; + + if (flags_stamp) + *flags_stamp = flags; + if (unlikely((flags & PVCLOCK_GUEST_STOPPED) != 0)) { src->flags &= ~PVCLOCK_GUEST_STOPPED; + if (flags_stamp) + *flags_stamp &= ~PVCLOCK_GUEST_STOPPED; pvclock_touch_watchdogs(); } @@ -136,7 +147,8 @@ void pvclock_read_wallclock(struct pvclock_wall_clock *wall_clock, rmb(); /* fetch time before checking version */ } while ((wall_clock->version & 1) || (version != wall_clock->version)); - delta = pvclock_clocksource_read(vcpu_time); /* time since system boot */ + /* time since system boot */ + delta = pvclock_clocksource_read(vcpu_time, NULL, NULL); delta += now.tv_sec * (u64)NSEC_PER_SEC + now.tv_nsec; now.tv_nsec = do_div(delta, NSEC_PER_SEC); diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c index 1ecb05d..3292cbc 100644 --- a/arch/x86/xen/time.c +++ b/arch/x86/xen/time.c @@ -46,7 +46,7 @@ u64 xen_clocksource_read(void) preempt_disable_notrace(); src = &__this_cpu_read(xen_vcpu)->time; - ret = pvclock_clocksource_read(src); + ret = pvclock_clocksource_read(src, NULL, NULL); preempt_enable_notrace(); return ret; } -- 2.7.4