| Message ID | 1451531020-29964-3-git-send-email-haozhong.zhang@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 12/30/2015 10:03 PM, Haozhong Zhang wrote: > 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 <haozhong.zhang@intel.com> > --- > 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; > + Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> although I still think that having !d->arch.vtsc would be better, even if not strictly required. > *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; > }
On 01/04/16 12:48, Boris Ostrovsky wrote: > On 12/30/2015 10:03 PM, Haozhong Zhang wrote: > >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 <haozhong.zhang@intel.com> > >--- > >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; > >+ > > Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> > > although I still think that having !d->arch.vtsc would be better, even if > not strictly required. > I'll add in the next version. Haozhong
>>> On 04.01.16 at 18:48, <boris.ostrovsky@oracle.com> wrote: > On 12/30/2015 10:03 PM, Haozhong Zhang wrote: >> 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 <haozhong.zhang@intel.com> >> --- >> 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; >> + > > Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> > > although I still think that having !d->arch.vtsc would be better, even > if not strictly required. Since Haozhong agreed, and for symmetry with patch 1 I'm going to commit with this added, plus ... >> @@ -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; ... with the comment here retained. Jan
On 01/08/16 02:05, Jan Beulich wrote: > >>> On 04.01.16 at 18:48, <boris.ostrovsky@oracle.com> wrote: > > On 12/30/2015 10:03 PM, Haozhong Zhang wrote: > >> 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 <haozhong.zhang@intel.com> > >> --- > >> 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; > >> + > > > > Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> > > > > although I still think that having !d->arch.vtsc would be better, even > > if not strictly required. > > Since Haozhong agreed, and for symmetry with patch 1 I'm going to > commit with this added, plus ... > > >> @@ -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; > > ... with the comment here retained. > And it's better to refine the comment like /* ignored by tsc_set_info if TSC scaling disabled */ Haozhong
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; }
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 <haozhong.zhang@intel.com> --- 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(-)