From patchwork Thu Dec 31 03:03:35 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Haozhong Zhang X-Patchwork-Id: 7935301 Return-Path: X-Original-To: patchwork-xen-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 5F5DBBEEE5 for ; Thu, 31 Dec 2015 03:07:11 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 2BF1F201BB for ; Thu, 31 Dec 2015 03:07:10 +0000 (UTC) Received: from lists.xen.org (lists.xenproject.org [50.57.142.19]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id BFA7220211 for ; Thu, 31 Dec 2015 03:07:08 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1aETXp-0000Rs-C3; Thu, 31 Dec 2015 03:04:53 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1aETXm-0000O5-Dq for xen-devel@lists.xen.org; Thu, 31 Dec 2015 03:04:50 +0000 Received: from [85.158.137.68] by server-3.bemta-3.messagelabs.com id 3A/30-01753-15B94865; Thu, 31 Dec 2015 03:04:49 +0000 X-Env-Sender: haozhong.zhang@intel.com X-Msg-Ref: server-7.tower-31.messagelabs.com!1451531085!5843005!2 X-Originating-IP: [134.134.136.20] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogMTM0LjEzNC4xMzYuMjAgPT4gMzU1MzU4\n X-StarScan-Received: X-StarScan-Version: 7.35.1; banners=-,-,- X-VirusChecked: Checked Received: (qmail 54184 invoked from network); 31 Dec 2015 03:04:48 -0000 Received: from mga02.intel.com (HELO mga02.intel.com) (134.134.136.20) by server-7.tower-31.messagelabs.com with SMTP; 31 Dec 2015 03:04:48 -0000 Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga101.jf.intel.com with ESMTP; 30 Dec 2015 19:04:48 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.20,503,1444719600"; d="scan'208";a="21536564" Received: from hz-desktop.sh.intel.com (HELO localhost) ([10.239.13.40]) by fmsmga004.fm.intel.com with ESMTP; 30 Dec 2015 19:04:46 -0800 From: Haozhong Zhang To: xen-devel@lists.xen.org, Jan Beulich , Boris Ostrovsky , Kevin Tian Date: Thu, 31 Dec 2015 11:03:35 +0800 Message-Id: <1451531020-29964-9-git-send-email-haozhong.zhang@intel.com> X-Mailer: git-send-email 2.4.8 In-Reply-To: <1451531020-29964-1-git-send-email-haozhong.zhang@intel.com> References: <1451531020-29964-1-git-send-email-haozhong.zhang@intel.com> Cc: Haozhong Zhang , Keir Fraser , Suravee Suthikulpanit , Andrew Cooper , Aravind Gopalakrishnan , Jun Nakajima Subject: [Xen-devel] [PATCH v3 08/13] x86/hvm: Setup TSC scaling ratio X-BeenThere: xen-devel@lists.xen.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patch adds a field tsc_scaling_ratio in struct hvm_vcpu to record the TSC scaling ratio, and sets it up when tsc_set_info() is called for a vcpu or when a vcpu is restored or reset. Before applying the TSC scaling ratio to CPU, we check its validity in tsc_set_info(). If an invalid ratio is given, we will leave the default value in tsc_scaling_ratio (i.e. ratio = 1) and setup guest TSC as if no TSC scaling is used: * For TSC_MODE_FAULT, - if a user-specified TSC frequency is given, we will set the guest TSC frequency to it; otherwise, we set it to the host TSC frequency. - if guest TSC frequency does not equal to host TSC frequency, we will emulate guest TSC (i.e. d->arch.vtsc is set to 1). In both cases, guest TSC runs in the guest TSC frequency. * For TSC_MODE_PVRDTSCP, - we set the guest TSC frequency to the host TSC frequency. - guest rdtsc is executed natively in the host TSC frequency as before. - if rdtscp is not available to guest, it will be emulated; otherwise, it will be executed natively. In both cases, guest rdtscp gets TSC in the host TSC frequency as before. Signed-off-by: Haozhong Zhang Reviewed-by: Boris Ostrovsky --- Changes in v3: (addressing Boris Ostrovsky's comments) * Remove redundant checks. * Update comments in tsc_set_info(): during initial boot -> during domain creation. (addressing Kevin Tian's comments) * Add a validation step to check TSC scaling ratio before applying it to the hardware. If the validation fails, we will fallback to Xen's original way to handle guest TSC. hvm_setup_tsc_scaling() is always called when the validation succeeds, so it shoud never fail now. xen/arch/x86/hvm/hvm.c | 41 +++++++++++++++++++++++++++++++++++++++ xen/arch/x86/hvm/svm/svm.c | 6 ++++-- xen/arch/x86/time.c | 19 +++++++++++++++--- xen/include/asm-x86/hvm/hvm.h | 6 ++++++ xen/include/asm-x86/hvm/svm/svm.h | 3 --- xen/include/asm-x86/hvm/vcpu.h | 2 ++ 6 files changed, 69 insertions(+), 8 deletions(-) diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c index 3648a44..3bf99b1 100644 --- a/xen/arch/x86/hvm/hvm.c +++ b/xen/arch/x86/hvm/hvm.c @@ -65,6 +65,7 @@ #include #include #include +#include #include #include #include @@ -301,6 +302,42 @@ int hvm_set_guest_pat(struct vcpu *v, u64 guest_pat) return 1; } +bool_t hvm_validate_tsc_scaling_ratio(uint32_t gtsc_khz) +{ + u64 ratio; + + if ( !hvm_funcs.tsc_scaling_supported ) + return FALSE; + + ratio = mul_u64_u32_div(1ULL << hvm_funcs.tsc_scaling_ratio_frac_bits, + gtsc_khz, cpu_khz); + + return (!ratio || ratio > hvm_funcs.max_tsc_scaling_ratio) ? FALSE : TRUE; +} + +void hvm_setup_tsc_scaling(struct vcpu *v) +{ + u64 ratio; + + if ( !hvm_funcs.tsc_scaling_supported ) + return; + + /* + * The multiplication of the first two terms may overflow a 64-bit + * integer, so use mul_u64_u32_div() instead to keep precision. + */ + ratio = mul_u64_u32_div(1ULL << hvm_funcs.tsc_scaling_ratio_frac_bits, + v->domain->arch.tsc_khz, cpu_khz); + + if ( ratio == 0 || ratio > hvm_funcs.max_tsc_scaling_ratio ) + return; + + v->arch.hvm_vcpu.tsc_scaling_ratio = ratio; + + if ( hvm_funcs.setup_tsc_scaling ) + hvm_funcs.setup_tsc_scaling(v); +} + void hvm_set_guest_tsc_fixed(struct vcpu *v, u64 guest_tsc, u64 at_tsc) { uint64_t tsc; @@ -2026,6 +2063,8 @@ static int hvm_load_cpu_ctxt(struct domain *d, hvm_domain_context_t *h) if ( hvm_funcs.load_cpu_ctxt(v, &ctxt) < 0 ) return -EINVAL; + hvm_setup_tsc_scaling(v); + v->arch.hvm_vcpu.msr_tsc_aux = ctxt.msr_tsc_aux; seg.limit = ctxt.idtr_limit; @@ -5504,6 +5543,8 @@ void hvm_vcpu_reset_state(struct vcpu *v, uint16_t cs, uint16_t ip) hvm_set_segment_register(v, x86_seg_gdtr, ®); hvm_set_segment_register(v, x86_seg_idtr, ®); + hvm_setup_tsc_scaling(v); + /* Sync AP's TSC with BSP's. */ v->arch.hvm_vcpu.cache_tsc_offset = v->domain->vcpu[0]->arch.hvm_vcpu.cache_tsc_offset; diff --git a/xen/arch/x86/hvm/svm/svm.c b/xen/arch/x86/hvm/svm/svm.c index 95795ce..b58f1e8 100644 --- a/xen/arch/x86/hvm/svm/svm.c +++ b/xen/arch/x86/hvm/svm/svm.c @@ -811,7 +811,7 @@ static uint64_t svm_scale_tsc(struct vcpu *v, uint64_t tsc) if ( !cpu_has_tsc_ratio || d->arch.vtsc ) return tsc; - return scale_tsc(tsc, vcpu_tsc_ratio(v)); + return scale_tsc(tsc, v->arch.hvm_vcpu.tsc_scaling_ratio); } static uint64_t svm_get_tsc_offset(uint64_t host_tsc, uint64_t guest_tsc, @@ -986,7 +986,7 @@ static inline void svm_tsc_ratio_save(struct vcpu *v) static inline void svm_tsc_ratio_load(struct vcpu *v) { if ( cpu_has_tsc_ratio && !v->domain->arch.vtsc ) - wrmsrl(MSR_AMD64_TSC_RATIO, vcpu_tsc_ratio(v)); + wrmsrl(MSR_AMD64_TSC_RATIO, v->arch.hvm_vcpu.tsc_scaling_ratio); } static void svm_ctxt_switch_from(struct vcpu *v) @@ -1193,6 +1193,8 @@ static int svm_vcpu_initialise(struct vcpu *v) svm_guest_osvw_init(v); + v->arch.hvm_vcpu.tsc_scaling_ratio = DEFAULT_TSC_RATIO; + return 0; } diff --git a/xen/arch/x86/time.c b/xen/arch/x86/time.c index b31634a..e69d9de 100644 --- a/xen/arch/x86/time.c +++ b/xen/arch/x86/time.c @@ -1864,7 +1864,8 @@ void tsc_set_info(struct domain *d, */ if ( tsc_mode == TSC_MODE_DEFAULT && host_tsc_is_safe() && (has_hvm_container_domain(d) ? - d->arch.tsc_khz == cpu_khz || cpu_has_tsc_ratio : + (d->arch.tsc_khz == cpu_khz || + hvm_validate_tsc_scaling_ratio(d->arch.tsc_khz)) : incarnation == 0) ) { case TSC_MODE_NEVER_EMULATE: @@ -1878,7 +1879,8 @@ void tsc_set_info(struct domain *d, d->arch.vtsc = !boot_cpu_has(X86_FEATURE_RDTSCP) || !host_tsc_is_safe(); enable_tsc_scaling = has_hvm_container_domain(d) && - cpu_has_tsc_ratio && !d->arch.vtsc; + !d->arch.vtsc && + hvm_validate_tsc_scaling_ratio(gtsc_khz ?: cpu_khz); d->arch.tsc_khz = (enable_tsc_scaling && gtsc_khz) ? gtsc_khz : cpu_khz; set_time_scale(&d->arch.vtsc_to_ns, d->arch.tsc_khz * 1000 ); d->arch.ns_to_vtsc = scale_reciprocal(d->arch.vtsc_to_ns); @@ -1897,9 +1899,20 @@ void tsc_set_info(struct domain *d, if ( has_hvm_container_domain(d) ) { hvm_set_rdtsc_exiting(d, d->arch.vtsc); - if ( d->vcpu && d->vcpu[0] && incarnation == 0 ) + if ( d->vcpu && d->vcpu[0] ) { /* + * TSC scaling ratio on BSP is set here during domain + * creation, while the same TSC scaling ratio on APs will + * be set in hvm_vcpu_reset_state(). + */ + if ( !d->arch.vtsc ) + hvm_setup_tsc_scaling(d->vcpu[0]); + + if ( incarnation ) + return; + + /* * set_tsc_offset() is called from hvm_vcpu_initialise() before * tsc_set_info(). New vtsc mode may require recomputing TSC * offset. diff --git a/xen/include/asm-x86/hvm/hvm.h b/xen/include/asm-x86/hvm/hvm.h index 12f9f24..6b49da8 100644 --- a/xen/include/asm-x86/hvm/hvm.h +++ b/xen/include/asm-x86/hvm/hvm.h @@ -226,6 +226,9 @@ struct hvm_function_table { int (*altp2m_vcpu_emulate_vmfunc)(struct cpu_user_regs *regs); uint64_t (*scale_tsc)(struct vcpu *v, uint64_t tsc); + + /* Architecture function to setup TSC scaling ratio */ + void (*setup_tsc_scaling)(struct vcpu *v); }; extern struct hvm_function_table hvm_funcs; @@ -261,6 +264,9 @@ void hvm_set_guest_tsc_fixed(struct vcpu *v, u64 guest_tsc, u64 at_tsc); u64 hvm_get_guest_tsc_fixed(struct vcpu *v, u64 at_tsc); #define hvm_get_guest_tsc(v) hvm_get_guest_tsc_fixed(v, 0) +bool_t hvm_validate_tsc_scaling_ratio(uint32_t gtsc_khz); +void hvm_setup_tsc_scaling(struct vcpu *v); + int hvm_set_mode(struct vcpu *v, int mode); void hvm_init_guest_time(struct domain *d); void hvm_set_guest_time(struct vcpu *v, u64 guest_time); diff --git a/xen/include/asm-x86/hvm/svm/svm.h b/xen/include/asm-x86/hvm/svm/svm.h index d60ec23..c954b7e 100644 --- a/xen/include/asm-x86/hvm/svm/svm.h +++ b/xen/include/asm-x86/hvm/svm/svm.h @@ -97,9 +97,6 @@ extern u32 svm_feature_flags; /* TSC rate */ #define DEFAULT_TSC_RATIO 0x0000000100000000ULL #define TSC_RATIO_RSVD_BITS 0xffffff0000000000ULL -#define TSC_RATIO(g_khz, h_khz) ( (((u64)(g_khz)<<32)/(u64)(h_khz)) & \ - ~TSC_RATIO_RSVD_BITS ) -#define vcpu_tsc_ratio(v) TSC_RATIO((v)->domain->arch.tsc_khz, cpu_khz) extern void svm_host_osvw_reset(void); extern void svm_host_osvw_init(void); diff --git a/xen/include/asm-x86/hvm/vcpu.h b/xen/include/asm-x86/hvm/vcpu.h index 152d9f3..901c988 100644 --- a/xen/include/asm-x86/hvm/vcpu.h +++ b/xen/include/asm-x86/hvm/vcpu.h @@ -175,6 +175,8 @@ struct hvm_vcpu { u64 msr_tsc_adjust; u64 msr_xss; + u64 tsc_scaling_ratio; + union { struct arch_vmx_struct vmx; struct arch_svm_struct svm;