Re: [PATCH] nvmm: Fix support for stable version

[Kamil Rytarowski]

Reviewed-by: Kamil Rytarowski <kamil@netbsd.org>

Paolo, could you please merge it?

On 13.10.2021 15:54, nia wrote:
> NVMM user version 1 is the version being shipped with netbsd-9,
> which is the most recent stable branch of NetBSD. This makes it
> possible to use the NVMM accelerator on the most recent NetBSD
> release, 9.2, which lacks nvmm_cpu_stop.
> 
> (CC'ing maintainers)
> 
> Signed-off-by: Nia Alarie <nia@NetBSD.org>
> ---
>  meson.build                 |  4 +---
>  target/i386/nvmm/nvmm-all.c | 10 ++++++++++
>  2 files changed, 11 insertions(+), 3 deletions(-)
> 
> diff --git a/meson.build b/meson.build
> index 15ef4d3c41..6e4d9b919a 100644
> --- a/meson.build
> +++ b/meson.build
> @@ -244,9 +244,7 @@ if not get_option('hax').disabled()
>    endif
>  endif
>  if targetos == 'netbsd'
> -  if cc.has_header_symbol('nvmm.h', 'nvmm_cpu_stop', required: 
> get_option('nvmm'))
> -    nvmm = cc.find_library('nvmm', required: get_option('nvmm'))
> -  endif
> +  nvmm = cc.find_library('nvmm', required: get_option('nvmm'))
>    if nvmm.found()
>      accelerators += 'CONFIG_NVMM'
>    endif
> diff --git a/target/i386/nvmm/nvmm-all.c b/target/i386/nvmm/nvmm-all.c
> index a488b00e90..4a10412427 100644
> --- a/target/i386/nvmm/nvmm-all.c
> +++ b/target/i386/nvmm/nvmm-all.c
> @@ -750,7 +750,11 @@ nvmm_vcpu_loop(CPUState *cpu)
>          nvmm_vcpu_pre_run(cpu);
>  
>          if (qatomic_read(&cpu->exit_request)) {
> +#if NVMM_USER_VERSION >= 2
>              nvmm_vcpu_stop(vcpu);
> +#else
> +            qemu_cpu_kick_self();
> +#endif
>          }
>  
>          /* Read exit_request before the kernel reads the immediate exit flag 
> */
> @@ -767,6 +771,7 @@ nvmm_vcpu_loop(CPUState *cpu)
>          switch (exit->reason) {
>          case NVMM_VCPU_EXIT_NONE:
>              break;
> +#if NVMM_USER_VERSION >= 2
>          case NVMM_VCPU_EXIT_STOPPED:
>              /*
>               * The kernel cleared the immediate exit flag; cpu->exit_request
> @@ -775,6 +780,7 @@ nvmm_vcpu_loop(CPUState *cpu)
>              smp_wmb();
>              qcpu->stop = true;
>              break;
> +#endif
>          case NVMM_VCPU_EXIT_MEMORY:
>              ret = nvmm_handle_mem(mach, vcpu);
>              break;
> @@ -888,8 +894,12 @@ nvmm_ipi_signal(int sigcpu)
>  {
>      if (current_cpu) {
>          struct qemu_vcpu *qcpu = get_qemu_vcpu(current_cpu);
> +#if NVMM_USER_VERSION >= 2
>          struct nvmm_vcpu *vcpu = &qcpu->vcpu;
>          nvmm_vcpu_stop(vcpu);
> +#else
> +        qcpu->stop = true;
> +#endif
>      }
>  }
>  
>