Please CC Michel as well, he originally commented that we should try to solve this in the DDX instead. And BTW: Why don't we just do the migration during the mmap call? Christian. Am 13.12.2017 um 22:28 schrieb Li, Samuel: > > Will do after some basic testing. > > Sam > > *From:*Deucher, Alexander > *Sent:* Wednesday, December 13, 2017 2:49 PM > *To:* Li, Samuel <Samuel.Li at amd.com>; Koenig, Christian > <Christian.Koenig at amd.com>; amd-gfx at lists.freedesktop.org > *Subject:* Re: FW: [PATCH v2 2/2] drm/amdgpu: Move to gtt before cpu > accesses dma buf. > > Please send the drm prime patch to dri-devel if you didn't already. > > Alex > > ------------------------------------------------------------------------ > > *From:*amd-gfx <amd-gfx-bounces at lists.freedesktop.org > <mailto:amd-gfx-bounces at lists.freedesktop.org>> on behalf of Samuel Li > <samuel.li at amd.com <mailto:samuel.li at amd.com>> > *Sent:* Wednesday, December 13, 2017 2:17:49 PM > *To:* Koenig, Christian; amd-gfx at lists.freedesktop.org > <mailto:amd-gfx at lists.freedesktop.org> > *Subject:* Re: FW: [PATCH v2 2/2] drm/amdgpu: Move to gtt before cpu > accesses dma buf. > > For the record. > > > On 2017-12-13 01:26 PM, Christian König wrote: > > Actually we try to avoid that drivers define their own dma_buf_ops > in DRM. > > > > That's why you have all those callbacks in drm_driver which just > mirror the dma_buf interface but unpack the GEM object from the > dma-buf object. > > > > There are quite a number of exceptions, but those drivers then > implement everything on their own because the DRM marshaling doesn't > make sense for them. > > > > Christian. > > > > Am 13.12.2017 um 19:01 schrieb Samuel Li: > >> That is an approach. The cost is to add a new call back, which is > not necessary though, since driver can always actually define their > own dma_buf_ops. > >> The intention here is to allow a driver reuse > drm_gem_prime_dmabuf_ops{}. If you would like to go this far, maybe a > more straight forward way is to export those ops, e.g. > drm_gem_map_attach, so that a driver can use them in its own definitions. > >> > >> Sam > >> > >> > >> > >> On 2017-12-13 05:23 AM, Christian König wrote: > >>> Something like the attached patch. Not even compile tested. > >>> > >>> Christian. > >>> > >>> Am 12.12.2017 um 20:13 schrieb Samuel Li: > >>>> Not sure if I understand your comments correctly. Currently > amdgpu prime reuses drm_gem_prime_dmabuf_ops{}, and it is defined as > static which is reasonable. I do not see an easier way to introduce > amdgpu_gem_begin_cpu_access(). > >>>> > >>>> Sam > >>>> > >>>> On 2017-12-12 01:30 PM, Christian König wrote: > >>>>>> +   while (amdgpu_dmabuf_ops.begin_cpu_access != > amdgpu_gem_begin_cpu_access) > >>>>> I would rather just add the four liner code to drm to forward > the begin_cpu_access callback into a drm_driver callback instead of > all this. > >>>>> > >>>>> But apart from that it looks good to me. > >>>>> > >>>>> Christian. > >>>>> > >>>>> Am 12.12.2017 um 19:14 schrieb Li, Samuel: > >>>>>> A gentle ping on this one, Christian, can you take a look at this? > >>>>>> > >>>>>> Sam > >>>>>> > >>>>>> -----Original Message----- > >>>>>> From: Li, Samuel > >>>>>> Sent: Friday, December 08, 2017 5:22 PM > >>>>>> To: amd-gfx at lists.freedesktop.org > <mailto:amd-gfx at lists.freedesktop.org> > >>>>>> Cc: Li, Samuel <Samuel.Li at amd.com <mailto:Samuel.Li at amd.com>> > >>>>>> Subject: [PATCH v2 2/2] drm/amdgpu: Move to gtt before cpu > accesses dma buf. > >>>>>> > >>>>>> To improve cpu read performance. This is implemented for APUs > currently. > >>>>>> > >>>>>> v2: Adapt to change > https://lists.freedesktop.org/archives/amd-gfx/2017-October/015174.html > >>>>>> > >>>>>> Change-Id: I7a583e23a9ee706e0edd2a46f4e4186a609368e3 > >>>>>> --- > >>>>>> drivers/gpu/drm/amd/amdgpu/amdgpu.h      | 2 ++ > >>>>>> drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c  | 2 +- > >>>>>> drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c | 58 > +++++++++++++++++++++++++++++++ > >>>>>>    3 files changed, 61 insertions(+), 1 deletion(-) > >>>>>> > >>>>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h > b/drivers/gpu/drm/amd/amdgpu/amdgpu.h > >>>>>> index f8657c3..193db70 100644 > >>>>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h > >>>>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h > >>>>>> @@ -417,6 +417,8 @@ amdgpu_gem_prime_import_sg_table(struct > drm_device *dev, struct dma_buf *amdgpu_gem_prime_export(struct > drm_device *dev, > >>>>>> struct drm_gem_object *gobj, > >>>>>>                        int flags); > >>>>>> +struct drm_gem_object *amdgpu_gem_prime_import(struct > drm_device *dev, > >>>>>> + struct dma_buf *dma_buf); > >>>>>>    int amdgpu_gem_prime_pin(struct drm_gem_object *obj); void > amdgpu_gem_prime_unpin(struct drm_gem_object *obj); struct > reservation_object *amdgpu_gem_prime_res_obj(struct drm_gem_object *); > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c > b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c > >>>>>> index 31383e0..df30b08 100644 > >>>>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c > >>>>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c > >>>>>> @@ -868,7 +868,7 @@ static struct drm_driver kms_driver = { > >>>>>>        .prime_handle_to_fd = drm_gem_prime_handle_to_fd, > >>>>>>        .prime_fd_to_handle = drm_gem_prime_fd_to_handle, > >>>>>>        .gem_prime_export = amdgpu_gem_prime_export, > >>>>>> -   .gem_prime_import = drm_gem_prime_import, > >>>>>> +   .gem_prime_import = amdgpu_gem_prime_import, > >>>>>>        .gem_prime_pin = amdgpu_gem_prime_pin, > >>>>>>        .gem_prime_unpin = amdgpu_gem_prime_unpin, > >>>>>>        .gem_prime_res_obj = amdgpu_gem_prime_res_obj, diff > --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c > b/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c > >>>>>> index ae9c106..de6f599 100644 > >>>>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c > >>>>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c > >>>>>> @@ -26,6 +26,7 @@ > >>>>>>    #include <drm/drmP.h> > >>>>>>     #include "amdgpu.h" > >>>>>> +#include "amdgpu_display.h" > >>>>>>    #include <drm/amdgpu_drm.h> > >>>>>>    #include <linux/dma-buf.h> > >>>>>>    @@ -164,6 +165,33 @@ struct reservation_object > *amdgpu_gem_prime_res_obj(struct drm_gem_object *obj) > >>>>>>        return bo->tbo.resv; > >>>>>>    } > >>>>>>    +static int amdgpu_gem_begin_cpu_access(struct dma_buf > *dma_buf, enum > >>>>>> +dma_data_direction direction) { > >>>>>> +   struct amdgpu_bo *bo = gem_to_amdgpu_bo(dma_buf->priv); > >>>>>> +   struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev); > >>>>>> +   struct ttm_operation_ctx ctx = { true, false }; > >>>>>> +   u32 domain = amdgpu_framebuffer_domains(adev); > >>>>>> +   long ret = 0; > >>>>>> +   bool reads = (direction == DMA_BIDIRECTIONAL || direction == > >>>>>> +DMA_FROM_DEVICE); > >>>>>> + > >>>>>> +   if (!reads || !(domain | AMDGPU_GEM_DOMAIN_GTT) || > bo->pin_count) > >>>>>> +       return 0; > >>>>>> + > >>>>>> +   /* move to gtt */ > >>>>>> +   ret = amdgpu_bo_reserve(bo, false); > >>>>>> +   if (unlikely(ret != 0)) > >>>>>> +       return ret; > >>>>>> + > >>>>>> + amdgpu_ttm_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_GTT); > >>>>>> +   ret = ttm_bo_validate(&bo->tbo, &bo->placement, &ctx); > >>>>>> + > >>>>>> +   amdgpu_bo_unreserve(bo); > >>>>>> +   return ret; > >>>>>> +} > >>>>>> + > >>>>>> +static struct dma_buf_ops amdgpu_dmabuf_ops; static atomic_t > aops_lock; > >>>>>> + > >>>>>>    struct dma_buf *amdgpu_gem_prime_export(struct drm_device *dev, > >>>>>> struct drm_gem_object *gobj, > >>>>>>                        int flags) > >>>>>> @@ -178,5 +206,35 @@ struct dma_buf > *amdgpu_gem_prime_export(struct drm_device *dev, > >>>>>>        buf = drm_gem_prime_export(dev, gobj, flags); > >>>>>>        if (!IS_ERR(buf)) > >>>>>> buf->file->f_mapping = dev->anon_inode->i_mapping; > >>>>>> + > >>>>>> +   while (amdgpu_dmabuf_ops.begin_cpu_access != > amdgpu_gem_begin_cpu_access) > >>>>>> +   { > >>>>>> +       if (!atomic_cmpxchg(&aops_lock, 0, 1)) { > >>>>>> + amdgpu_dmabuf_ops = *(buf->ops); > >>>>>> + amdgpu_dmabuf_ops.begin_cpu_access = amdgpu_gem_begin_cpu_access; > >>>>>> +       } > >>>>>> +   } > >>>>>> +   buf->ops = &amdgpu_dmabuf_ops; > >>>>>> + > >>>>>>        return buf; > >>>>>>    } > >>>>>> + > >>>>>> +struct drm_gem_object *amdgpu_gem_prime_import(struct > drm_device *dev, > >>>>>> + struct dma_buf *dma_buf) > >>>>>> +{ > >>>>>> +   struct drm_gem_object *obj; > >>>>>> + > >>>>>> +   if (dma_buf->ops == &amdgpu_dmabuf_ops) { > >>>>>> +       obj = dma_buf->priv; > >>>>>> +       if (obj->dev == dev) { > >>>>>> +           /* > >>>>>> +            * Importing dmabuf exported from out own gem > increases > >>>>>> +            * refcount on gem itself instead of f_count of > dmabuf. > >>>>>> +            */ > >>>>>> + drm_gem_object_get(obj); > >>>>>> +           return obj; > >>>>>> +       } > >>>>>> +   } > >>>>>> + > >>>>>> +   return drm_gem_prime_import(dev, dma_buf); } > >>>>>> -- > >>>>>> 2.7.4 > >>>>>> > > > > > > _______________________________________________ > amd-gfx mailing list > amd-gfx at lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/amd-gfx -------------- next part -------------- An HTML attachment was scrubbed... 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