Implement XEN_SYSCTL_CPU_HOTPLUG_* calls to allow for enabling/disabling CPU cores in runtime.
Signed-off-by: Mykyta Poturai <[email protected]> --- xen/arch/arm/sysctl.c | 67 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 67 insertions(+) diff --git a/xen/arch/arm/sysctl.c b/xen/arch/arm/sysctl.c index 32cab4feff..ca8fb550fd 100644 --- a/xen/arch/arm/sysctl.c +++ b/xen/arch/arm/sysctl.c @@ -12,6 +12,7 @@ #include <xen/dt-overlay.h> #include <xen/errno.h> #include <xen/hypercall.h> +#include <xen/cpu.h> #include <asm/arm64/sve.h> #include <public/sysctl.h> @@ -23,6 +24,68 @@ void arch_do_physinfo(struct xen_sysctl_physinfo *pi) XEN_SYSCTL_PHYSCAP_ARM_SVE_MASK); } +static long cpu_up_helper(void *data) +{ + unsigned long cpu = (unsigned long) data; + return cpu_up(cpu); +} + +static long cpu_down_helper(void *data) +{ + unsigned long cpu = (unsigned long) data; + return cpu_down(cpu); +} + +static long smt_up_down_helper(void *data) +{ + bool up = (bool) data; + unsigned int cpu; + int ret; + + for_each_present_cpu ( cpu ) + { + if ( cpu == 0 ) + continue; + + if ( up ) + ret = cpu_up(cpu); + else + ret = cpu_down(cpu); + + if ( ret ) + return ret; + } + + return 0; +} + +static long cpu_hotplug_sysctl(struct xen_sysctl_cpu_hotplug *hotplug) +{ + bool up; + + switch (hotplug->op) { + case XEN_SYSCTL_CPU_HOTPLUG_ONLINE: + if ( hotplug->cpu == 0 ) + return -EINVAL; + return continue_hypercall_on_cpu(0, cpu_up_helper, _p(hotplug->cpu)); + + case XEN_SYSCTL_CPU_HOTPLUG_OFFLINE: + if ( hotplug->cpu == 0 ) + return -EINVAL; + return continue_hypercall_on_cpu(0, cpu_down_helper, _p(hotplug->cpu)); + + case XEN_SYSCTL_CPU_HOTPLUG_SMT_ENABLE: + case XEN_SYSCTL_CPU_HOTPLUG_SMT_DISABLE: + if ( CONFIG_NR_CPUS <= 1 ) + return 0; + up = hotplug->op == XEN_SYSCTL_CPU_HOTPLUG_SMT_ENABLE; + return continue_hypercall_on_cpu(0, smt_up_down_helper, _p(up)); + + default: + return -EINVAL; + } +} + long arch_do_sysctl(struct xen_sysctl *sysctl, XEN_GUEST_HANDLE_PARAM(xen_sysctl_t) u_sysctl) { @@ -34,6 +97,10 @@ long arch_do_sysctl(struct xen_sysctl *sysctl, ret = dt_overlay_sysctl(&sysctl->u.dt_overlay); break; + case XEN_SYSCTL_cpu_hotplug: + ret = cpu_hotplug_sysctl(&sysctl->u.cpu_hotplug); + break; + default: ret = -ENOSYS; break; -- 2.34.1
