From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vitaly Kuznetsov Subject: [PATCH RFC 2/6] x86/hyper-v: add a function to read both TSC and TSC page value simulateneously Date: Fri, 1 Dec 2017 14:13:17 +0100 Message-ID: <20171201131321.918-3-vkuznets@redhat.com> References: <20171201131321.918-1-vkuznets@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Stephen Hemminger , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Haiyang Zhang , linux-kernel@vger.kernel.org, devel@linuxdriverproject.org, Ingo Molnar , Andy Lutomirski , "H. Peter Anvin" , Paolo Bonzini , Thomas Gleixner To: kvm@vger.kernel.org, x86@kernel.org Return-path: In-Reply-To: <20171201131321.918-1-vkuznets@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: driverdev-devel-bounces@linuxdriverproject.org Sender: "devel" List-Id: kvm.vger.kernel.org This is going to be used from KVM code were 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 --- arch/x86/include/asm/mshyperv.h | 24 ++++++++++++++++++++---- 1 file changed, 20 insertions(+), 4 deletions(-) diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h index 5400add2885b..2611d2c49f27 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 +382,13 @@ 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) +{ + *cur_tsc = rdtsc(); + + return cur_tsc; +} #endif #endif -- 2.14.3