Re: [PATCH v2 09/16] xen/riscv: introduce vcpu_kick() implementation

[Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>]

On 1/22/26 5:47 PM, Oleksii Kurochko wrote:
> Add a RISC-V implementation of vcpu_kick(), which unblocks the target
> vCPU and sends an event check IPI if the vCPU was running on another
> processor. This mirrors the behavior of Arm and enables proper vCPU
> wakeup handling on RISC-V.
>
> Remove the stub implementation from stubs.c, as it is now provided by
> arch/riscv/domain.c.
>
> Signed-off-by: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>
> Acked-by: Jan Beulich <jbeulich@xxxxxxxx>
> ---
> Changes in v2:
>   - Add Acked-by: Jan Beulich <jbeulich@xxxxxxxx>.
> ---
>   xen/arch/riscv/domain.c | 14 ++++++++++++++
>   xen/arch/riscv/stubs.c  |  5 -----
>   2 files changed, 14 insertions(+), 5 deletions(-)
>
> diff --git a/xen/arch/riscv/domain.c b/xen/arch/riscv/domain.c
> index e38c0db62cac..13ac384c4b76 100644
> --- a/xen/arch/riscv/domain.c
> +++ b/xen/arch/riscv/domain.c
> @@ -1,8 +1,10 @@
>   /* SPDX-License-Identifier: GPL-2.0-only */
>   
> +#include <xen/cpumask.h>
>   #include <xen/init.h>
>   #include <xen/mm.h>
>   #include <xen/sched.h>
> +#include <xen/smp.h>
>   #include <xen/vmap.h>
>   
>   #include <asm/bitops.h>
> @@ -240,3 +242,15 @@ void vcpu_sync_interrupts(struct vcpu *v)
>   #   error "Update vsieh"
>   #endif
>   }
> +
> +void vcpu_kick(struct vcpu *v)
> +{
> +    bool running = v->is_running;
> +
> +    vcpu_unblock(v);
> +    if ( running && v != current )
> +    {
> +        perfc_incr(vcpu_kick);
Because of this it is needed to introduce:
  PERFCOUNTER(vcpu_kick, "vcpu: notify other vcpu")
Otherwise randconfig build will fail when CONFIG_PERF_COUNTERS=y.

I would like to ask if it would be okay to add it xen/include/xen/perfc_defn.h
just after PERFCOUNTER(need_flush_tlb_flush,...) or would it be better to have
it in arch specific perfc_defn.h?

~ Oleksii