Hi Gavin,
> From: Gavin Shan <gs...@redhat.com>
> Sent: Wednesday, October 11, 2023 8:09 AM
> To: Salil Mehta <salil.me...@huawei.com>; qemu-devel@nongnu.org;
> qemu-...@nongnu.org
> Cc: m...@kernel.org; jean-phili...@linaro.org; Jonathan Cameron
> <jonathan.came...@huawei.com>; lpieral...@kernel.org;
> peter.mayd...@linaro.org; richard.hender...@linaro.org;
> imamm...@redhat.com; andrew.jo...@linux.dev; da...@redhat.com;
> phi...@linaro.org; eric.au...@redhat.com; oliver.up...@linux.dev;
> pbonz...@redhat.com; m...@redhat.com; w...@kernel.org; raf...@kernel.org;
> alex.ben...@linaro.org; li...@armlinux.org.uk;
> dar...@os.amperecomputing.com; il...@os.amperecomputing.com;
> vis...@os.amperecomputing.com; karl.heub...@oracle.com;
> miguel.l...@oracle.com; salil.me...@opnsrc.net; zhukeqian
> <zhukeqi...@huawei.com>; wangxiongfeng (C) <wangxiongfe...@huawei.com>;
> wangyanan (Y) <wangyana...@huawei.com>; jiakern...@gmail.com;
> maob...@loongson.cn; lixiang...@loongson.cn; Linuxarm <linux...@huawei.com>
> Subject: Re: [PATCH V4 01/10] accel/kvm: Extract common KVM vCPU
> {creation,parking} code
>
> Hi Salil,
>
> On 10/10/23 06:35, Salil Mehta wrote:
> > KVM vCPU creation is done once during the initialization of the VM when Qemu
> > thread is spawned. This is common to all the architectures.
> >
> > Hot-unplug of vCPU results in destruction of the vCPU object in QOM but the
> > corresponding KVM vCPU object in the Host KVM is not destroyed and its
> > representative KVM vCPU object/context in Qemu is parked.
> >
> > Refactor common logic so that some APIs could be reused by vCPU Hotplug
> > code.
> >
> > Signed-off-by: Salil Mehta <salil.me...@huawei.com>
> > ---
> > accel/kvm/kvm-all.c | 64 ++++++++++++++++++++++++++++++++----------
> > accel/kvm/trace-events | 4 +++
> > include/sysemu/kvm.h | 16 +++++++++++
> > 3 files changed, 69 insertions(+), 15 deletions(-)
> >
>
> With the following one comment addressed:
>
> Reviewed-by: Gavin Shan <gs...@redhat.com>
Thanks
[...]
> > diff --git a/accel/kvm/trace-events b/accel/kvm/trace-events
> > index 399aaeb0ec..08e2dc253f 100644
> > --- a/accel/kvm/trace-events
> > +++ b/accel/kvm/trace-events
> > @@ -9,6 +9,10 @@ kvm_device_ioctl(int fd, int type, void *arg) "dev fd
> %d, type 0x%x, arg %p"
> > kvm_failed_reg_get(uint64_t id, const char *msg) "Warning: Unable to
> > retrieve ONEREG %" PRIu64 " from KVM: %s"
> > kvm_failed_reg_set(uint64_t id, const char *msg) "Warning: Unable to set
> > ONEREG %" PRIu64 " to KVM: %s"
> > kvm_init_vcpu(int cpu_index, unsigned long arch_cpu_id) "index: %d id:
> > %lu"
> > +kvm_create_vcpu(int cpu_index, unsigned long arch_cpu_id) "creating KVM
> > cpu: cpu_index: %d arch vcpu-id: %lu"
> > +kvm_get_vcpu(unsigned long arch_cpu_id) "unparking KVM vcpu: arch vcpu-id:
> > %lu"
> > +kvm_destroy_vcpu(int cpu_index, unsigned long arch_cpu_id) "destroy vcpu:
> > cpu_index: %d arch vcpu-id: %lu"
> > +kvm_park_vcpu(int cpu_index, unsigned long arch_cpu_id) "parking KVM vcpu:
> > cpu_index: %d arch vcpu-id: %lu"
>
> I don't think we need the duplicate identifiers like "creating KVM cpu"
> since the event name can serve the purpose. Besides, the parameters
> are descriptive by "index: %d id: %lu", used by kvm_init_vcpu(). We just
> need to follow that pattern. Otherwise, inconsistent output will be printed
> by kvm_init_vcpu() and kvm_get_vcpu(). So I would change them like below:
>
> kvm_init_vcpu(int cpu_index, unsigned long arch_cpu_id) "index: %d id: %lu"
> kvm_create_vcpu(int cpu_index, unsigned long arch_cpu_id) "index: %d id: %lu"
> kvm_get_vcpu(unsigned long arch_cpu_id) "id: %lu"
> kvm_destroy_vcpu(int cpu_index, unsigned long arch_cpu_id) "index: %d id: %lu"
> kvm_park_vcpu(int cpu_index, unsigned long arch_cpu_id) "index: %d id: %lu"
No problem. Will fix
Only executed below to check for new trace counters:
Qemu> info trace-events
Thanks
Salil.
