| Message ID | 20190809145833.1020-41-jgross@suse.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | xen: add core scheduling support | expand |
On 09.08.2019 16:58, Juergen Gross wrote: > When core or socket scheduling are active enabling or disabling smt is > not possible as that would require a major host reconfiguration. > > Add a bool sched_disable_smt_switching which will be set for core or > socket scheduling. > > Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: Jan Beulich <jbeulich@suse.com>
diff --git a/xen/arch/x86/sysctl.c b/xen/arch/x86/sysctl.c index c50d910a1c..a4c4d868b6 100644 --- a/xen/arch/x86/sysctl.c +++ b/xen/arch/x86/sysctl.c @@ -204,6 +204,11 @@ long arch_do_sysctl( ret = -EOPNOTSUPP; break; } + if ( sched_disable_smt_switching ) + { + ret = -EBUSY; + break; + } plug = op == XEN_SYSCTL_CPU_HOTPLUG_SMT_ENABLE; fn = smt_up_down_helper; hcpu = _p(plug); diff --git a/xen/common/schedule.c b/xen/common/schedule.c index afd4170730..b94fd2431a 100644 --- a/xen/common/schedule.c +++ b/xen/common/schedule.c @@ -57,6 +57,7 @@ integer_param("sched_ratelimit_us", sched_ratelimit_us); /* Number of vcpus per struct sched_unit. */ static unsigned int __read_mostly sched_granularity = 1; +bool __read_mostly sched_disable_smt_switching; const cpumask_t *sched_res_mask = &cpumask_all; /* Common lock for free cpus. */ diff --git a/xen/include/xen/sched.h b/xen/include/xen/sched.h index e868646f0e..39355f5d67 100644 --- a/xen/include/xen/sched.h +++ b/xen/include/xen/sched.h @@ -1021,6 +1021,7 @@ static inline bool is_vcpu_online(const struct vcpu *v) } extern bool sched_smt_power_savings; +extern bool sched_disable_smt_switching; extern enum cpufreq_controller { FREQCTL_none, FREQCTL_dom0_kernel, FREQCTL_xen
When core or socket scheduling are active enabling or disabling smt is not possible as that would require a major host reconfiguration. Add a bool sched_disable_smt_switching which will be set for core or socket scheduling. Signed-off-by: Juergen Gross <jgross@suse.com> --- V1: - new patch V2: - EBUSY as return code (Jan Beulich, Dario Faggioli) - __read_mostly for sched_disable_smt_switching (Jan Beulich) --- xen/arch/x86/sysctl.c | 5 +++++ xen/common/schedule.c | 1 + xen/include/xen/sched.h | 1 + 3 files changed, 7 insertions(+)