Re: [QEMU PATCH v5 06/13] virtio-gpu: Support context init feature with virglrenderer

[Huang Rui <ray.huang@xxxxxxx>]

On Mon, Sep 18, 2023 at 02:07:25PM +0800, Akihiko Odaki wrote:
> On 2023/09/18 14:43, Huang Rui wrote:
> > On Sun, Sep 17, 2023 at 01:49:19PM +0800, Akihiko Odaki wrote:
> >> On 2023/09/17 14:45, Huang Rui wrote:
> >>> On Sat, Sep 16, 2023 at 06:42:04PM +0800, Akihiko Odaki wrote:
> >>>> On 2023/09/16 19:32, Huang Rui wrote:
> >>>>> On Fri, Sep 15, 2023 at 11:20:46PM +0800, Akihiko Odaki wrote:
> >>>>>> On 2023/09/15 20:11, Huang Rui wrote:
> >>>>>>> Patch "virtio-gpu: CONTEXT_INIT feature" has added the context_init
> >>>>>>> feature flags.
> >>>>>>> We would like to enable the feature with virglrenderer, so add to 
> >>>>>>> create
> >>>>>>> virgl renderer context with flags using context_id when valid.
> >>>>>>>
> >>>>>>> Originally-by: Antonio Caggiano <antonio.caggiano@xxxxxxxxxxxxx>
> >>>>>>> Signed-off-by: Huang Rui <ray.huang@xxxxxxx>
> >>>>>>> ---
> >>>>>>>
> >>>>>>> V4 -> V5:
> >>>>>>>         - Inverted patch 5 and 6 because we should configure
> >>>>>>>           HAVE_VIRGL_CONTEXT_INIT firstly. (Philippe)
> >>>>>>>
> >>>>>>>      hw/display/virtio-gpu-virgl.c | 13 +++++++++++--
> >>>>>>>      hw/display/virtio-gpu.c       |  2 ++
> >>>>>>>      2 files changed, 13 insertions(+), 2 deletions(-)
> >>>>>>>
> >>>>>>> diff --git a/hw/display/virtio-gpu-virgl.c 
> >>>>>>> b/hw/display/virtio-gpu-virgl.c
> >>>>>>> index 8bb7a2c21f..312953ec16 100644
> >>>>>>> --- a/hw/display/virtio-gpu-virgl.c
> >>>>>>> +++ b/hw/display/virtio-gpu-virgl.c
> >>>>>>> @@ -106,8 +106,17 @@ static void virgl_cmd_context_create(VirtIOGPU 
> >>>>>>> *g,
> >>>>>>>          trace_virtio_gpu_cmd_ctx_create(cc.hdr.ctx_id,
> >>>>>>>                                          cc.debug_name);
> >>>>>>>      
> >>>>>>> -    virgl_renderer_context_create(cc.hdr.ctx_id, cc.nlen,
> >>>>>>> -                                  cc.debug_name);
> >>>>>>> +    if (cc.context_init) {
> >>>>>>> +#ifdef HAVE_VIRGL_CONTEXT_INIT
> >>>>>>> +        virgl_renderer_context_create_with_flags(cc.hdr.ctx_id,
> >>>>>>> +                                                 cc.context_init,
> >>>>>>> +                                                 cc.nlen,
> >>>>>>> +                                                 cc.debug_name);
> >>>>>>> +        return;
> >>>>>>> +#endif
> >>>>>>
> >>>>>> This should deal with the case when context_init is set while
> >>>>>> HAVE_VIRGL_CONTEXT_INIT is not defined.
> >>>>>
> >>>>> Actually, I received the comment below before:
> >>>>>
> >>>>> https://lore.kernel.org/qemu-devel/32588d0e-a1f2-30c4-5e9f-e6e7c4190b65@xxxxxxxxxx/
> >>>>>
> >>>>> At original patch set, I have the case while HAVE_VIRGL_CONTEXT_INIT is 
> >>>>> set
> >>>>> but HAVE_VIRGL_CONTEXT_INIT is not defined. But I think we may encounter
> >>>>> the case that virgl_renderer_context_create_with_flags is not defined in
> >>>>> virglrenderer early version. Should I bring the error message back?
> >>>>>
> >>>>> Thanks,
> >>>>> Ray
> >>>>
> >>>> I suggest checking VIRTIO_GPU_FLAG_CONTEXT_INIT_ENABLED instead of
> >>>> reporting an error here. Perhaps it may be easier to add #ifdef around:
> >>>>    > +    DEFINE_PROP_BIT("context_init", VirtIOGPU, 
> >>>> parent_obj.conf.flags,
> >>>>    > +                    VIRTIO_GPU_FLAG_CONTEXT_INIT_ENABLED, false),
> >>>
> >>> How about below changes: >
> >>> ---
> >>> diff --git a/hw/display/virtio-gpu-virgl.c b/hw/display/virtio-gpu-virgl.c
> >>> index 8bb7a2c21f..54a3cfe136 100644
> >>> --- a/hw/display/virtio-gpu-virgl.c
> >>> +++ b/hw/display/virtio-gpu-virgl.c
> >>> @@ -106,8 +106,15 @@ static void virgl_cmd_context_create(VirtIOGPU *g,
> >>>        trace_virtio_gpu_cmd_ctx_create(cc.hdr.ctx_id,
> >>>                                        cc.debug_name);
> >>>
> >>> -    virgl_renderer_context_create(cc.hdr.ctx_id, cc.nlen,
> >>> -                                  cc.debug_name);
> >>> +    if (cc.context_init && virtio_gpu_context_init_enabled(g->conf)) {
> >>> +        virgl_renderer_context_create_with_flags(cc.hdr.ctx_id,
> >>> +                                                 cc.context_init,
> >>> +                                                 cc.nlen,
> >>> +                                                 cc.debug_name);
> >>> +        return;
> >>> +    }
> >>> +
> >>> +    virgl_renderer_context_create(cc.hdr.ctx_id, cc.nlen, cc.debug_name);
> >>>    }
> >>>
> >>>    static void virgl_cmd_context_destroy(VirtIOGPU *g,
> >>> diff --git a/hw/display/virtio-gpu.c b/hw/display/virtio-gpu.c
> >>> index be16efbd38..6ff2c8e92d 100644
> >>> --- a/hw/display/virtio-gpu.c
> >>> +++ b/hw/display/virtio-gpu.c
> >>> @@ -1508,6 +1508,10 @@ static Property virtio_gpu_properties[] = {
> >>>        DEFINE_PROP_BIT("blob", VirtIOGPU, parent_obj.conf.flags,
> >>>                        VIRTIO_GPU_FLAG_BLOB_ENABLED, false),
> >>>        DEFINE_PROP_SIZE("hostmem", VirtIOGPU, parent_obj.conf.hostmem, 0),
> >>> +#ifdef HAVE_VIRGL_CONTEXT_INIT
> >>> +    DEFINE_PROP_BIT("context_init", VirtIOGPU, parent_obj.conf.flags,
> >>> +                    VIRTIO_GPU_FLAG_CONTEXT_INIT_ENABLED, true),
> >>> +#endif
> >>>        DEFINE_PROP_END_OF_LIST(),
> >>>    };
> >>>
> >>
> >> It looks better, but not having #ifdef around
> >> virgl_renderer_context_create_with_flags() will result in a link error
> >> with old virglrenderer.
> > 
> > Hmm, right, it seems that we have to have a "#ifdef" around here. Or do you
> > have any better idea?
> 
> Having #ifdef is the right direction.

OK, so we can use cc.context_init and make sure context_init function
enabled. Please check below:

---
diff --git a/hw/display/virtio-gpu-virgl.c b/hw/display/virtio-gpu-virgl.c
index 8bb7a2c21f..8363674ebc 100644
--- a/hw/display/virtio-gpu-virgl.c
+++ b/hw/display/virtio-gpu-virgl.c
@@ -106,8 +106,17 @@ static void virgl_cmd_context_create(VirtIOGPU *g,
     trace_virtio_gpu_cmd_ctx_create(cc.hdr.ctx_id,
                                     cc.debug_name);

-    virgl_renderer_context_create(cc.hdr.ctx_id, cc.nlen,
-                                  cc.debug_name);
+    if (cc.context_init && 
virtio_gpu_context_init_enabled(g->parent_obj.conf)) {
+#ifdef HAVE_VIRGL_CONTEXT_INIT
+        virgl_renderer_context_create_with_flags(cc.hdr.ctx_id,
+                                                 cc.context_init,
+                                                 cc.nlen,
+                                                 cc.debug_name);
+        return;
+#endif
+    }
+
+    virgl_renderer_context_create(cc.hdr.ctx_id, cc.nlen, cc.debug_name);
 }

 static void virgl_cmd_context_destroy(VirtIOGPU *g,
diff --git a/hw/display/virtio-gpu.c b/hw/display/virtio-gpu.c
index be16efbd38..6ff2c8e92d 100644
--- a/hw/display/virtio-gpu.c
+++ b/hw/display/virtio-gpu.c
@@ -1508,6 +1508,10 @@ static Property virtio_gpu_properties[] = {
     DEFINE_PROP_BIT("blob", VirtIOGPU, parent_obj.conf.flags,
                     VIRTIO_GPU_FLAG_BLOB_ENABLED, false),
     DEFINE_PROP_SIZE("hostmem", VirtIOGPU, parent_obj.conf.hostmem, 0),
+#ifdef HAVE_VIRGL_CONTEXT_INIT
+    DEFINE_PROP_BIT("context_init", VirtIOGPU, parent_obj.conf.flags,
+                    VIRTIO_GPU_FLAG_CONTEXT_INIT_ENABLED, true),
+#endif
     DEFINE_PROP_END_OF_LIST(),
 };