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

[Jan Beulich <jbeulich@xxxxxxxx>]

On 06.02.2026 17:36, Oleksii Kurochko wrote:
> 
> 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?

Arch-specific please - it's not used by x86 nor ppc.

Jan