[Linaro-mm-sig] Re: [PATCH v2 01/23] drm/msm: Pre-allocate hw_fence

On Mon, Mar 20, 2023 at 9:52 AM Christian König christian.koenig@amd.com wrote:

Am 20.03.23 um 15:43 schrieb Rob Clark:

...

From: Rob Clark robdclark@chromium.org

Avoid allocating memory in job_run() by pre-allocating the hw_fence.

Signed-off-by: Rob Clark robdclark@chromium.org

drivers/gpu/drm/msm/msm_fence.c | 12 +++++++++--- drivers/gpu/drm/msm/msm_fence.h | 3 ++- drivers/gpu/drm/msm/msm_gem_submit.c | 7 +++++++ drivers/gpu/drm/msm/msm_ringbuffer.c | 2 +- 4 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_fence.c b/drivers/gpu/drm/msm/msm_fence.c index 56641408ea74..bab3d84f1686 100644 --- a/drivers/gpu/drm/msm/msm_fence.c +++ b/drivers/gpu/drm/msm/msm_fence.c @@ -99,7 +99,7 @@ static const struct dma_fence_ops msm_fence_ops = { };

struct dma_fence * -msm_fence_alloc(struct msm_fence_context *fctx) +msm_fence_alloc(void) { struct msm_fence *f;

@@ -107,10 +107,16 @@ msm_fence_alloc(struct msm_fence_context *fctx) if (!f) return ERR_PTR(-ENOMEM);

• return &f->base;
  

+}

+void +msm_fence_init(struct dma_fence *fence, struct msm_fence_context *fctx) +{

• struct msm_fence *f = to_msm_fence(fence);
  

• f->fctx = fctx;
  
  dma_fence_init(&f->base, &msm_fence_ops, &fctx->spinlock,
                 fctx->context, ++fctx->last_fence);
  

• return &f->base;
  

  }

diff --git a/drivers/gpu/drm/msm/msm_fence.h b/drivers/gpu/drm/msm/msm_fence.h index 7f1798c54cd1..f913fa22d8fe 100644 --- a/drivers/gpu/drm/msm/msm_fence.h +++ b/drivers/gpu/drm/msm/msm_fence.h @@ -61,7 +61,8 @@ void msm_fence_context_free(struct msm_fence_context *fctx); bool msm_fence_completed(struct msm_fence_context *fctx, uint32_t fence); void msm_update_fence(struct msm_fence_context *fctx, uint32_t fence);

-struct dma_fence * msm_fence_alloc(struct msm_fence_context *fctx); +struct dma_fence * msm_fence_alloc(void); +void msm_fence_init(struct dma_fence *fence, struct msm_fence_context *fctx);

static inline bool fence_before(uint32_t a, uint32_t b) diff --git a/drivers/gpu/drm/msm/msm_gem_submit.c b/drivers/gpu/drm/msm/msm_gem_submit.c index be4bf77103cd..2570c018b0cb 100644 --- a/drivers/gpu/drm/msm/msm_gem_submit.c +++ b/drivers/gpu/drm/msm/msm_gem_submit.c @@ -41,6 +41,13 @@ static struct msm_gem_submit *submit_create(struct drm_device *dev, if (!submit) return ERR_PTR(-ENOMEM);

• submit->hw_fence = msm_fence_alloc();
  

• if (IS_ERR(submit->hw_fence)) {
  

•         ret = PTR_ERR(submit->hw_fence);
  

•         kfree(submit);
  

•         return ERR_PTR(ret);
  

• }
  

• ret = drm_sched_job_init(&submit->base, queue->entity, queue);
  if (ret) {
          kfree(submit);
  

You probably need some error handling here or otherwise leak submit->hw_fence.

ah, right.. thx

BR, -R

Apart from that looks good to me.

Christian.

...

diff --git a/drivers/gpu/drm/msm/msm_ringbuffer.c b/drivers/gpu/drm/msm/msm_ringbuffer.c index 57a8e9564540..a62b45e5a8c3 100644 --- a/drivers/gpu/drm/msm/msm_ringbuffer.c +++ b/drivers/gpu/drm/msm/msm_ringbuffer.c @@ -18,7 +18,7 @@ static struct dma_fence *msm_job_run(struct drm_sched_job *job) struct msm_gpu *gpu = submit->gpu; int i;

• submit->hw_fence = msm_fence_alloc(fctx);
  

• msm_fence_init(submit->hw_fence, fctx);
  
  for (i = 0; i < submit->nr_bos; i++) {
          struct drm_gem_object *obj = &submit->bos[i].obj->base;