From mboxrd@z Thu Jan 1 00:00:00 1970 From: Haozhong Zhang Subject: [PATCH v3 02/13] x86/time.c: Use correct guest TSC frequency in tsc_get_info() Date: Thu, 31 Dec 2015 11:03:29 +0800 Message-ID: <1451531020-29964-3-git-send-email-haozhong.zhang@intel.com> References: <1451531020-29964-1-git-send-email-haozhong.zhang@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1451531020-29964-1-git-send-email-haozhong.zhang@intel.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: xen-devel@lists.xen.org, Jan Beulich , Boris Ostrovsky , Kevin Tian Cc: Haozhong Zhang , Keir Fraser , Suravee Suthikulpanit , Andrew Cooper , Aravind Gopalakrishnan , Jun Nakajima List-Id: xen-devel@lists.xenproject.org When the TSC mode of a HVM container is TSC_MODE_DEFAULT or TSC_MODE_PVRDTSCP and no TSC emulation is used, the existing tsc_get_info() uses the host TSC frequency (cpu_khz) as the guest TSC frequency. However, tsc_set_info() may set the guest TSC frequency to a value different than the host. In order to keep consistent to tsc_set_info(), this patch makes tsc_get_info() use the value set by tsc_set_info() as the guest TSC frequency. Signed-off-by: Haozhong Zhang --- Changes in v3: (addressing Boris Ostrovsky's comments) * Use this_cpu(cpu_time).tsc_scale for both scaling and non-scaling cases. xen/arch/x86/time.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/xen/arch/x86/time.c b/xen/arch/x86/time.c index 0059b6a..d83f068 100644 --- a/xen/arch/x86/time.c +++ b/xen/arch/x86/time.c @@ -1749,6 +1749,9 @@ void tsc_get_info(struct domain *d, uint32_t *tsc_mode, uint64_t *elapsed_nsec, uint32_t *gtsc_khz, uint32_t *incarnation) { + bool_t enable_tsc_scaling = has_hvm_container_domain(d) && + cpu_has_tsc_ratio; + *incarnation = d->arch.incarnation; *tsc_mode = d->arch.tsc_mode; @@ -1769,7 +1772,7 @@ void tsc_get_info(struct domain *d, uint32_t *tsc_mode, } tsc = rdtsc(); *elapsed_nsec = scale_delta(tsc, &d->arch.vtsc_to_ns); - *gtsc_khz = cpu_khz; + *gtsc_khz = enable_tsc_scaling ? d->arch.tsc_khz : cpu_khz; break; case TSC_MODE_PVRDTSCP: if ( d->arch.vtsc ) @@ -1780,9 +1783,9 @@ void tsc_get_info(struct domain *d, uint32_t *tsc_mode, else { tsc = rdtsc(); - *elapsed_nsec = scale_delta(tsc, &d->arch.vtsc_to_ns) - + *elapsed_nsec = scale_delta(tsc, &this_cpu(cpu_time).tsc_scale) - d->arch.vtsc_offset; - *gtsc_khz = 0; /* ignored by tsc_set_info */ + *gtsc_khz = enable_tsc_scaling ? d->arch.tsc_khz : 0; } break; } -- 2.4.8