From: Chris Wilson Date: Tue, 21 May 2019 21:11:34 +0000 (+0100) Subject: drm/i915: Allow specification of parallel execbuf X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=a88b6e4cbafd;p=openwrt%2Fstaging%2Fblogic.git drm/i915: Allow specification of parallel execbuf There is a desire to split a task onto two engines and have them run at the same time, e.g. scanline interleaving to spread the workload evenly. Through the use of the out-fence from the first execbuf, we can coordinate secondary execbuf to only become ready simultaneously with the first, so that with all things idle the second execbufs are executed in parallel with the first. The key difference here between the new EXEC_FENCE_SUBMIT and the existing EXEC_FENCE_IN is that the in-fence waits for the completion of the first request (so that all of its rendering results are visible to the second execbuf, the more common userspace fence requirement). Since we only have a single input fence slot, userspace cannot mix an in-fence and a submit-fence. It has to use one or the other! This is not such a harsh requirement, since by virtue of the submit-fence, the secondary execbuf inherit all of the dependencies from the first request, and for the application the dependencies should be common between the primary and secondary execbuf. Suggested-by: Tvrtko Ursulin Testcase: igt/gem_exec_fence/parallel Link: https://github.com/intel/media-driver/pull/546 Signed-off-by: Chris Wilson Cc: Tvrtko Ursulin Reviewed-by: Tvrtko Ursulin Link: https://patchwork.freedesktop.org/patch/msgid/20190521211134.16117-10-chris@chris-wilson.co.uk --- diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c index 5061cb32856b..83d2eb9e74cb 100644 --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -443,6 +443,7 @@ static int i915_getparam_ioctl(struct drm_device *dev, void *data, case I915_PARAM_HAS_EXEC_CAPTURE: case I915_PARAM_HAS_EXEC_BATCH_FIRST: case I915_PARAM_HAS_EXEC_FENCE_ARRAY: + case I915_PARAM_HAS_EXEC_SUBMIT_FENCE: /* For the time being all of these are always true; * if some supported hardware does not have one of these * features this value needs to be provided from diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c index d6c5220addd0..7ce25b54c57b 100644 --- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c @@ -2318,6 +2318,7 @@ i915_gem_do_execbuffer(struct drm_device *dev, { struct i915_execbuffer eb; struct dma_fence *in_fence = NULL; + struct dma_fence *exec_fence = NULL; struct sync_file *out_fence = NULL; int out_fence_fd = -1; int err; @@ -2360,11 +2361,24 @@ i915_gem_do_execbuffer(struct drm_device *dev, return -EINVAL; } + if (args->flags & I915_EXEC_FENCE_SUBMIT) { + if (in_fence) { + err = -EINVAL; + goto err_in_fence; + } + + exec_fence = sync_file_get_fence(lower_32_bits(args->rsvd2)); + if (!exec_fence) { + err = -EINVAL; + goto err_in_fence; + } + } + if (args->flags & I915_EXEC_FENCE_OUT) { out_fence_fd = get_unused_fd_flags(O_CLOEXEC); if (out_fence_fd < 0) { err = out_fence_fd; - goto err_in_fence; + goto err_exec_fence; } } @@ -2494,6 +2508,13 @@ i915_gem_do_execbuffer(struct drm_device *dev, goto err_request; } + if (exec_fence) { + err = i915_request_await_execution(eb.request, exec_fence, + eb.engine->bond_execute); + if (err < 0) + goto err_request; + } + if (fences) { err = await_fence_array(&eb, fences); if (err) @@ -2555,6 +2576,8 @@ err_destroy: err_out_fence: if (out_fence_fd != -1) put_unused_fd(out_fence_fd); +err_exec_fence: + dma_fence_put(exec_fence); err_in_fence: dma_fence_put(in_fence); return err; diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h index e2da9027bcdf..bdb00ec1f8be 100644 --- a/include/uapi/drm/i915_drm.h +++ b/include/uapi/drm/i915_drm.h @@ -604,6 +604,12 @@ typedef struct drm_i915_irq_wait { */ #define I915_PARAM_MMAP_GTT_COHERENT 52 +/* + * Query whether DRM_I915_GEM_EXECBUFFER2 supports coordination of parallel + * execution through use of explicit fence support. + * See I915_EXEC_FENCE_OUT and I915_EXEC_FENCE_SUBMIT. + */ +#define I915_PARAM_HAS_EXEC_SUBMIT_FENCE 53 /* Must be kept compact -- no holes and well documented */ typedef struct drm_i915_getparam { @@ -1126,7 +1132,16 @@ struct drm_i915_gem_execbuffer2 { */ #define I915_EXEC_FENCE_ARRAY (1<<19) -#define __I915_EXEC_UNKNOWN_FLAGS (-(I915_EXEC_FENCE_ARRAY<<1)) +/* + * Setting I915_EXEC_FENCE_SUBMIT implies that lower_32_bits(rsvd2) represent + * a sync_file fd to wait upon (in a nonblocking manner) prior to executing + * the batch. + * + * Returns -EINVAL if the sync_file fd cannot be found. + */ +#define I915_EXEC_FENCE_SUBMIT (1 << 20) + +#define __I915_EXEC_UNKNOWN_FLAGS (-(I915_EXEC_FENCE_SUBMIT << 1)) #define I915_EXEC_CONTEXT_ID_MASK (0xffffffff) #define i915_execbuffer2_set_context_id(eb2, context) \