[PATCH 4/5] drm/amdgpu: MCBP based on DRM scheduler (v8)

[Zhu, Jiadong]

[AMD Official Use Only - General]

It is a macro defined in amdgpu_ring.h, calling function pointer preempt_ib directly:
#define amdgpu_ring_preempt_ib(r) (r)->funcs->preempt_ib(r)

The real ring's hook is assigned  in gfx_v9_0.c:
static const struct amdgpu_ring_funcs gfx_v9_0_ring_funcs_gfx = {
...
.preempt_ib = gfx_v9_0_ring_preempt_ib, //please have a check this line existed.
...
}

Here is the eglinfo on my board, I have once built mesa component (22.3.0-devel), which may update the libEGL_mesa.so
EGL client extensions string:
    EGL_EXT_device_base EGL_EXT_device_enumeration EGL_EXT_device_query
    EGL_EXT_platform_base EGL_KHR_client_get_all_proc_addresses
    EGL_EXT_client_extensions EGL_KHR_debug EGL_EXT_platform_device
    EGL_EXT_platform_x11 EGL_KHR_platform_x11 EGL_EXT_platform_xcb
    EGL_MESA_platform_gbm EGL_KHR_platform_gbm
    EGL_MESA_platform_surfaceless

GBM platform:
EGL API version: 1.5
EGL vendor string: Mesa Project
EGL version string: 1.5
EGL client APIs: OpenGL OpenGL_ES
EGL extensions string:
    EGL_ANDROID_blob_cache EGL_ANDROID_native_fence_sync
    EGL_EXT_buffer_age EGL_EXT_create_context_robustness
    EGL_EXT_image_dma_buf_import EGL_EXT_image_dma_buf_import_modifiers
    EGL_EXT_protected_surface EGL_IMG_context_priority EGL_KHR_cl_event2
    EGL_KHR_config_attribs EGL_KHR_context_flush_control
    EGL_KHR_create_context EGL_KHR_create_context_no_error
    EGL_KHR_fence_sync EGL_KHR_get_all_proc_addresses
    EGL_KHR_gl_colorspace EGL_KHR_gl_renderbuffer_image
    EGL_KHR_gl_texture_2D_image EGL_KHR_gl_texture_3D_image
    EGL_KHR_gl_texture_cubemap_image EGL_KHR_image EGL_KHR_image_base
    EGL_KHR_image_pixmap EGL_KHR_no_config_context EGL_KHR_reusable_sync
    EGL_KHR_surfaceless_context EGL_EXT_pixel_format_float
    EGL_KHR_wait_sync EGL_MESA_configless_context EGL_MESA_drm_image
    EGL_MESA_image_dma_buf_export EGL_MESA_query_driver

Thanks,
Jiadong

-----Original Message-----
From: Michel Dänzer <michel at daenzer.net>
Sent: Monday, October 31, 2022 8:02 PM
To: Zhu, Jiadong <Jiadong.Zhu at amd.com>
Cc: Andrey Grodzovsky <Andrey.Grodzovsky at amd.com>; Huang, Ray <Ray.Huang at amd.com>; Tuikov, Luben <Luben.Tuikov at amd.com>; Koenig, Christian <Christian.Koenig at amd.com>; amd-gfx at lists.freedesktop.org
Subject: Re: [PATCH 4/5] drm/amdgpu: MCBP based on DRM scheduler (v8)

On 2022-10-18 11:08, jiadong.zhu at amd.com wrote:
> From: "Jiadong.Zhu" <Jiadong.Zhu at amd.com>
>
> Trigger Mid-Command Buffer Preemption according to the priority of the
> software rings and the hw fence signalling condition.
>
> The muxer saves the locations of the indirect buffer frames from the
> software ring together with the fence sequence number in its fifo
> queue, and pops out those records when the fences are signalled. The
> locations are used to resubmit packages in preemption scenarios by coping the chunks from the software ring.
>
> v2: Update comment style.
> v3: Fix conflict caused by previous modifications.
> v4: Remove unnecessary prints.
> v5: Fix corner cases for resubmission cases.
> v6: Refactor functions for resubmission, calling fence_process in irq handler.
> v7: Solve conflict for removing amdgpu_sw_ring.c.
> v8: Add time threshold to judge if preemption request is needed.
>
> Cc: Christian Koenig <Christian.Koenig at amd.com>
> Cc: Luben Tuikov <Luben.Tuikov at amd.com>
> Cc: Andrey Grodzovsky <Andrey.Grodzovsky at amd.com>
> Cc: Michel Dänzer <michel at daenzer.net>
> Signed-off-by: Jiadong.Zhu <Jiadong.Zhu at amd.com>
> Acked-by: Luben Tuikov <luben.tuikov at amd.com>
> Acked-by: Huang Rui <ray.huang at amd.com>

[...]

> +/* Trigger Mid-Command Buffer Preemption (MCBP) and find if we need
> +to resubmit. */ int amdgpu_mcbp_trigger_preempt(struct
> +amdgpu_ring_mux *mux) {
> +     int r;
> +
> +     spin_lock(&mux->lock);
> +     mux->pending_trailing_fence_signaled = true;
> +     r = amdgpu_ring_preempt_ib(mux->real_ring);
> +     spin_unlock(&mux->lock);
> +     return r;
> +}

AFAICT amdgpu_mcbp_trigger_preempt is used only in this file, so it should be declared static.

(I didn't audit the other new functions added by this series for this, just happened to notice this one)


--
Earthling Michel Dänzer            |                  https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fredhat.com%2F&data=05%7C01%7Cjiadong.zhu%40amd.com%7Cfaca0a3e35964bcbb24708dabb37b284%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C638028145150743814%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=BcnmJQ5jUdI%2BGnKvUpn3agyxTD4iTSweGxEQKUlQpxI%3D&reserved=0
Libre software enthusiast          |         Mesa and Xwayland developer