Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753760AbdLHKw4 (ORCPT ); Fri, 8 Dec 2017 05:52:56 -0500 Received: from mx1.redhat.com ([209.132.183.28]:36674 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753306AbdLHKuT (ORCPT ); Fri, 8 Dec 2017 05:50:19 -0500 From: Vitaly Kuznetsov To: kvm@vger.kernel.org, x86@kernel.org Cc: Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , "K. Y. Srinivasan" , Haiyang Zhang , Stephen Hemminger , "Michael Kelley (EOSG)" , Andy Lutomirski , Mohammed Gamal , Cathy Avery , linux-kernel@vger.kernel.org, devel@linuxdriverproject.org Subject: [PATCH 2/6] x86/hyper-v: add a function to read both TSC and TSC page value simulateneously Date: Fri, 8 Dec 2017 11:49:56 +0100 Message-Id: <20171208105000.25116-3-vkuznets@redhat.com> In-Reply-To: <20171208105000.25116-1-vkuznets@redhat.com> References: <20171208105000.25116-1-vkuznets@redhat.com> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Fri, 08 Dec 2017 10:50:19 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2588 Lines: 86 This is going to be used from KVM code where we need to get both TSC and TSC page value. When Hyper-V code is compiled out just return rdtsc(), this will allow us to avoid ugly ifdefs in non-Hyper-V code. Signed-off-by: Vitaly Kuznetsov --- RFC -> v1: - EXPORT_SYMBOL_GPL(hv_get_tsc_page) [kbuild test robot] - BUG() in !CONFIG_HYPERV_TSCPAGE case [Stephen Hemminger, Paolo Bonzini] - 'were' -> 'where' [Andrew Jones] --- arch/x86/hyperv/hv_init.c | 1 + arch/x86/include/asm/mshyperv.h | 23 +++++++++++++++++++---- 2 files changed, 20 insertions(+), 4 deletions(-) diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c index 21f9d53d9f00..1a6c63f721bc 100644 --- a/arch/x86/hyperv/hv_init.c +++ b/arch/x86/hyperv/hv_init.c @@ -37,6 +37,7 @@ struct ms_hyperv_tsc_page *hv_get_tsc_page(void) { return tsc_pg; } +EXPORT_SYMBOL_GPL(hv_get_tsc_page); static u64 read_hv_clock_tsc(struct clocksource *arg) { diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h index 5400add2885b..a0b34994f453 100644 --- a/arch/x86/include/asm/mshyperv.h +++ b/arch/x86/include/asm/mshyperv.h @@ -323,9 +323,10 @@ static inline void hyperv_setup_mmu_ops(void) {} #ifdef CONFIG_HYPERV_TSCPAGE struct ms_hyperv_tsc_page *hv_get_tsc_page(void); -static inline u64 hv_read_tsc_page(const struct ms_hyperv_tsc_page *tsc_pg) +static inline u64 hv_read_tsc_page_tsc(const struct ms_hyperv_tsc_page *tsc_pg, + u64 *cur_tsc) { - u64 scale, offset, cur_tsc; + u64 scale, offset; u32 sequence; /* @@ -356,7 +357,7 @@ static inline u64 hv_read_tsc_page(const struct ms_hyperv_tsc_page *tsc_pg) scale = READ_ONCE(tsc_pg->tsc_scale); offset = READ_ONCE(tsc_pg->tsc_offset); - cur_tsc = rdtsc_ordered(); + *cur_tsc = rdtsc_ordered(); /* * Make sure we read sequence after we read all other values @@ -366,7 +367,14 @@ static inline u64 hv_read_tsc_page(const struct ms_hyperv_tsc_page *tsc_pg) } while (READ_ONCE(tsc_pg->tsc_sequence) != sequence); - return mul_u64_u64_shr(cur_tsc, scale, 64) + offset; + return mul_u64_u64_shr(*cur_tsc, scale, 64) + offset; +} + +static inline u64 hv_read_tsc_page(const struct ms_hyperv_tsc_page *tsc_pg) +{ + u64 cur_tsc; + + return hv_read_tsc_page_tsc(tsc_pg, &cur_tsc); } #else @@ -374,5 +382,12 @@ static inline struct ms_hyperv_tsc_page *hv_get_tsc_page(void) { return NULL; } + +static inline u64 hv_read_tsc_page_tsc(const struct ms_hyperv_tsc_page *tsc_pg, + u64 *cur_tsc) +{ + BUG(); + return U64_MAX; +} #endif #endif -- 2.14.3