[Intel-gfx] [PATCH v3 1/3] drm/i915: simplify allocation of driver-internal requests
Daniel Vetter
daniel at ffwll.ch
Tue Jan 12 05:50:28 PST 2016
On Thu, Jan 07, 2016 at 10:20:50AM +0000, Dave Gordon wrote:
> There are a number of places where the driver needs a request, but isn't
> working on behalf of any specific user or in a specific context. At
> present, we associate them with the per-engine default context. A future
> patch will abolish those per-engine context pointers; but we can already
> eliminate a lot of the references to them, just by making the allocator
> allow NULL as a shorthand for "an appropriate context for this ring",
> which will mean that the callers don't need to know anything about how
> the "appropriate context" is found (e.g. per-ring vs per-device, etc).
>
> So this patch renames the existing i915_gem_request_alloc(), and makes
> it local (static inline), and replaces it with a wrapper that provides
> a default if the context is NULL, and also has a nicer calling
> convention (doesn't require a pointer to an output parameter). Then we
> change all callers to use the new convention:
> OLD:
> err = i915_gem_request_alloc(ring, user_ctx, &req);
> if (err) ...
> NEW:
> req = i915_gem_request_alloc(ring, user_ctx);
> if (IS_ERR(req)) ...
> OLD:
> err = i915_gem_request_alloc(ring, ring->default_context, &req);
> if (err) ...
> NEW:
> req = i915_gem_request_alloc(ring, NULL);
> if (IS_ERR(req)) ...
>
> Signed-off-by: Dave Gordon <david.s.gordon at intel.com>
> ---
> drivers/gpu/drm/i915/i915_drv.h | 6 ++--
> drivers/gpu/drm/i915/i915_gem.c | 55 +++++++++++++++++++++++-------
> drivers/gpu/drm/i915/i915_gem_execbuffer.c | 14 +++++---
> drivers/gpu/drm/i915/intel_display.c | 6 ++--
> drivers/gpu/drm/i915/intel_lrc.c | 9 +++--
> drivers/gpu/drm/i915/intel_overlay.c | 24 ++++++-------
> 6 files changed, 74 insertions(+), 40 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index c6dd4db..c2b000a 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -2260,9 +2260,9 @@ struct drm_i915_gem_request {
>
> };
>
> -int i915_gem_request_alloc(struct intel_engine_cs *ring,
> - struct intel_context *ctx,
> - struct drm_i915_gem_request **req_out);
> +struct drm_i915_gem_request * __must_check
> +i915_gem_request_alloc(struct intel_engine_cs *engine,
> + struct intel_context *ctx);
> void i915_gem_request_cancel(struct drm_i915_gem_request *req);
> void i915_gem_request_free(struct kref *req_ref);
> int i915_gem_request_add_to_client(struct drm_i915_gem_request *req,
> diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> index 6c60e04..c908ed1 100644
> --- a/drivers/gpu/drm/i915/i915_gem.c
> +++ b/drivers/gpu/drm/i915/i915_gem.c
> @@ -2688,9 +2688,10 @@ void i915_gem_request_free(struct kref *req_ref)
> kmem_cache_free(req->i915->requests, req);
> }
>
> -int i915_gem_request_alloc(struct intel_engine_cs *ring,
> - struct intel_context *ctx,
> - struct drm_i915_gem_request **req_out)
> +static inline int
> +__i915_gem_request_alloc(struct intel_engine_cs *ring,
> + struct intel_context *ctx,
> + struct drm_i915_gem_request **req_out)
> {
> struct drm_i915_private *dev_priv = to_i915(ring->dev);
> struct drm_i915_gem_request *req;
> @@ -2753,6 +2754,31 @@ err:
> return ret;
> }
>
> +/**
> + * i915_gem_request_alloc - allocate a request structure
> + *
> + * @engine: engine that we wish to issue the request on.
> + * @ctx: context that the request will be associated with.
> + * This can be NULL if the request is not directly related to
> + * any specific user context, in which case this function will
> + * choose an appropriate context to use.
> + *
> + * Returns a pointer to the allocated request if successful,
> + * or an error code if not.
> + */
> +struct drm_i915_gem_request *
> +i915_gem_request_alloc(struct intel_engine_cs *engine,
> + struct intel_context *ctx)
> +{
> + struct drm_i915_gem_request *req;
> + int err;
> +
> + if (ctx == NULL)
> + ctx = engine->default_context;
I think NULL vs. explicit dev_priv->kernel_context (or whatever it is) is
semantically equivalent enough that it doesn't matter. And we can easily
sed this (or an entire patch series for easy rebasing) if we change our
minds.
Acked-by: Daniel Vetter <daniel.vetter at ffwll.ch>
> + err = __i915_gem_request_alloc(engine, ctx, &req);
> + return err ? ERR_PTR(err) : req;
> +}
> +
> void i915_gem_request_cancel(struct drm_i915_gem_request *req)
> {
> intel_ring_reserved_space_cancel(req->ringbuf);
> @@ -3170,9 +3196,13 @@ __i915_gem_object_sync(struct drm_i915_gem_object *obj,
> return 0;
>
> if (*to_req == NULL) {
> - ret = i915_gem_request_alloc(to, to->default_context, to_req);
> - if (ret)
> - return ret;
> + struct drm_i915_gem_request *req;
> +
> + req = i915_gem_request_alloc(to, NULL);
> + if (IS_ERR(req))
> + return PTR_ERR(req);
> +
> + *to_req = req;
> }
>
> trace_i915_gem_ring_sync_to(*to_req, from, from_req);
> @@ -3372,9 +3402,9 @@ int i915_gpu_idle(struct drm_device *dev)
> if (!i915.enable_execlists) {
> struct drm_i915_gem_request *req;
>
> - ret = i915_gem_request_alloc(ring, ring->default_context, &req);
> - if (ret)
> - return ret;
> + req = i915_gem_request_alloc(ring, NULL);
> + if (IS_ERR(req))
> + return PTR_ERR(req);
>
> ret = i915_switch_context(req);
> if (ret) {
> @@ -4869,10 +4899,9 @@ i915_gem_init_hw(struct drm_device *dev)
> for_each_ring(ring, dev_priv, i) {
> struct drm_i915_gem_request *req;
>
> - WARN_ON(!ring->default_context);
> -
> - ret = i915_gem_request_alloc(ring, ring->default_context, &req);
> - if (ret) {
> + req = i915_gem_request_alloc(ring, NULL);
> + if (IS_ERR(req)) {
> + ret = PTR_ERR(req);
> i915_gem_cleanup_ringbuffer(dev);
> goto out;
> }
> diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
> index dccb517..dc6caeb 100644
> --- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
> +++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
> @@ -1381,6 +1381,7 @@ i915_gem_do_execbuffer(struct drm_device *dev, void *data,
> struct drm_i915_gem_exec_object2 *exec)
> {
> struct drm_i915_private *dev_priv = dev->dev_private;
> + struct drm_i915_gem_request *req = NULL;
> struct eb_vmas *eb;
> struct drm_i915_gem_object *batch_obj;
> struct drm_i915_gem_exec_object2 shadow_exec_entry;
> @@ -1602,11 +1603,13 @@ i915_gem_do_execbuffer(struct drm_device *dev, void *data,
> params->batch_obj_vm_offset = i915_gem_obj_offset(batch_obj, vm);
>
> /* Allocate a request for this batch buffer nice and early. */
> - ret = i915_gem_request_alloc(ring, ctx, ¶ms->request);
> - if (ret)
> + req = i915_gem_request_alloc(ring, ctx);
> + if (IS_ERR(req)) {
> + ret = PTR_ERR(req);
> goto err_batch_unpin;
> + }
>
> - ret = i915_gem_request_add_to_client(params->request, file);
> + ret = i915_gem_request_add_to_client(req, file);
> if (ret)
> goto err_batch_unpin;
>
> @@ -1622,6 +1625,7 @@ i915_gem_do_execbuffer(struct drm_device *dev, void *data,
> params->dispatch_flags = dispatch_flags;
> params->batch_obj = batch_obj;
> params->ctx = ctx;
> + params->request = req;
>
> ret = dev_priv->gt.execbuf_submit(params, args, &eb->vmas);
>
> @@ -1645,8 +1649,8 @@ err:
> * must be freed again. If it was submitted then it is being tracked
> * on the active request list and no clean up is required here.
> */
> - if (ret && params->request)
> - i915_gem_request_cancel(params->request);
> + if (ret && req)
> + i915_gem_request_cancel(req);
>
> mutex_unlock(&dev->struct_mutex);
>
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index ed9ab60..1f8f781 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -11700,9 +11700,11 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc,
> obj->last_write_req);
> } else {
> if (!request) {
> - ret = i915_gem_request_alloc(ring, ring->default_context, &request);
> - if (ret)
> + request = i915_gem_request_alloc(ring, NULL);
> + if (IS_ERR(request)) {
> + ret = PTR_ERR(request);
> goto cleanup_unpin;
> + }
> }
>
> ret = dev_priv->display.queue_flip(dev, crtc, fb, obj, request,
> diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
> index 8096c6a..8b6542d 100644
> --- a/drivers/gpu/drm/i915/intel_lrc.c
> +++ b/drivers/gpu/drm/i915/intel_lrc.c
> @@ -2510,11 +2510,10 @@ int intel_lr_context_deferred_alloc(struct intel_context *ctx,
> if (ctx != ring->default_context && ring->init_context) {
> struct drm_i915_gem_request *req;
>
> - ret = i915_gem_request_alloc(ring,
> - ctx, &req);
> - if (ret) {
> - DRM_ERROR("ring create req: %d\n",
> - ret);
> + req = i915_gem_request_alloc(ring, ctx);
> + if (IS_ERR(req)) {
> + ret = PTR_ERR(req);
> + DRM_ERROR("ring create req: %d\n", ret);
> goto error_ringbuf;
> }
>
> diff --git a/drivers/gpu/drm/i915/intel_overlay.c b/drivers/gpu/drm/i915/intel_overlay.c
> index 76f1980..9168413 100644
> --- a/drivers/gpu/drm/i915/intel_overlay.c
> +++ b/drivers/gpu/drm/i915/intel_overlay.c
> @@ -240,9 +240,9 @@ static int intel_overlay_on(struct intel_overlay *overlay)
> WARN_ON(overlay->active);
> WARN_ON(IS_I830(dev) && !(dev_priv->quirks & QUIRK_PIPEA_FORCE));
>
> - ret = i915_gem_request_alloc(ring, ring->default_context, &req);
> - if (ret)
> - return ret;
> + req = i915_gem_request_alloc(ring, NULL);
> + if (IS_ERR(req))
> + return PTR_ERR(req);
>
> ret = intel_ring_begin(req, 4);
> if (ret) {
> @@ -283,9 +283,9 @@ static int intel_overlay_continue(struct intel_overlay *overlay,
> if (tmp & (1 << 17))
> DRM_DEBUG("overlay underrun, DOVSTA: %x\n", tmp);
>
> - ret = i915_gem_request_alloc(ring, ring->default_context, &req);
> - if (ret)
> - return ret;
> + req = i915_gem_request_alloc(ring, NULL);
> + if (IS_ERR(req))
> + return PTR_ERR(req);
>
> ret = intel_ring_begin(req, 2);
> if (ret) {
> @@ -349,9 +349,9 @@ static int intel_overlay_off(struct intel_overlay *overlay)
> * of the hw. Do it in both cases */
> flip_addr |= OFC_UPDATE;
>
> - ret = i915_gem_request_alloc(ring, ring->default_context, &req);
> - if (ret)
> - return ret;
> + req = i915_gem_request_alloc(ring, NULL);
> + if (IS_ERR(req))
> + return PTR_ERR(req);
>
> ret = intel_ring_begin(req, 6);
> if (ret) {
> @@ -423,9 +423,9 @@ static int intel_overlay_release_old_vid(struct intel_overlay *overlay)
> /* synchronous slowpath */
> struct drm_i915_gem_request *req;
>
> - ret = i915_gem_request_alloc(ring, ring->default_context, &req);
> - if (ret)
> - return ret;
> + req = i915_gem_request_alloc(ring, NULL);
> + if (IS_ERR(req))
> + return PTR_ERR(req);
>
> ret = intel_ring_begin(req, 2);
> if (ret) {
> --
> 1.9.1
>
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> Intel-gfx at lists.freedesktop.org
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--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
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