If the GEM objects being rendered with in this request have been exported via dma-buf to a third party, hook ourselves into the dma-buf reservation object so that the third party can serialise with our rendering via the dma-buf fences.
Testcase: igt/prime_busy Signed-off-by: Chris Wilson <[email protected]> --- drivers/gpu/drm/i915/i915_gem_dmabuf.c | 40 +++++++++++++++++++++++++++--- drivers/gpu/drm/i915/i915_gem_execbuffer.c | 30 ++++++++++++++++++++-- 2 files changed, 65 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_dmabuf.c b/drivers/gpu/drm/i915/i915_gem_dmabuf.c index 80bbe43a2e92..8a5f88aef6e8 100644 --- a/drivers/gpu/drm/i915/i915_gem_dmabuf.c +++ b/drivers/gpu/drm/i915/i915_gem_dmabuf.c @@ -23,9 +23,13 @@ * Authors: * Dave Airlie <[email protected]> */ + +#include <linux/dma-buf.h> +#include <linux/reservation.h> + #include <drm/drmP.h> + #include "i915_drv.h" -#include <linux/dma-buf.h> static struct drm_i915_gem_object *dma_buf_to_obj(struct dma_buf *buf) { @@ -218,25 +222,55 @@ static const struct dma_buf_ops i915_dmabuf_ops = { .end_cpu_access = i915_gem_end_cpu_access, }; +static void export_fences(struct drm_i915_gem_object *obj, + struct dma_buf *dma_buf) +{ + struct reservation_object *resv = dma_buf->resv; + struct drm_i915_gem_request *req; + int idx; + + mutex_lock(&obj->base.dev->struct_mutex); + + for (idx = 0; idx < ARRAY_SIZE(obj->last_read_req); idx++) { + req = obj->last_read_req[idx]; + if (!req) + continue; + + if (reservation_object_reserve_shared(resv) == 0) + reservation_object_add_shared_fence(resv, &req->fence); + } + + req = obj->last_write_req; + if (req) + reservation_object_add_excl_fence(resv, &req->fence); + + mutex_unlock(&obj->base.dev->struct_mutex); +} + struct dma_buf *i915_gem_prime_export(struct drm_device *dev, struct drm_gem_object *gem_obj, int flags) { struct drm_i915_gem_object *obj = to_intel_bo(gem_obj); DEFINE_DMA_BUF_EXPORT_INFO(exp_info); + struct dma_buf *dma_buf; exp_info.ops = &i915_dmabuf_ops; exp_info.size = gem_obj->size; exp_info.flags = flags; exp_info.priv = gem_obj; - if (obj->ops->dmabuf_export) { int ret = obj->ops->dmabuf_export(obj); if (ret) return ERR_PTR(ret); } - return dma_buf_export(&exp_info); + dma_buf = dma_buf_export(&exp_info); + if (IS_ERR(dma_buf)) + return dma_buf; + + export_fences(obj, dma_buf); + return dma_buf; } static int i915_gem_object_get_pages_dmabuf(struct drm_i915_gem_object *obj) diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c index 39c53d97833a..1cc4ba7e87a4 100644 --- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c @@ -26,13 +26,17 @@ * */ +#include <linux/dma_remapping.h> +#include <linux/reservation.h> +#include <linux/uaccess.h> + #include <drm/drmP.h> #include <drm/i915_drm.h> + #include "i915_drv.h" +#include "i915_gem_dmabuf.h" #include "i915_trace.h" #include "intel_drv.h" -#include <linux/dma_remapping.h> -#include <linux/uaccess.h> #define __EXEC_OBJECT_HAS_PIN (1<<31) #define __EXEC_OBJECT_HAS_FENCE (1<<30) @@ -1086,6 +1090,27 @@ i915_gem_validate_context(struct drm_device *dev, struct drm_file *file, return ctx; } +static void eb_export_fence(struct drm_i915_gem_object *obj, + struct drm_i915_gem_request *req) +{ + struct reservation_object *resv; + + resv = i915_gem_object_get_dmabuf_resv(obj); + if (!resv) + return; + + /* Ignore errors from failing to allocate the new fence, we can't + * handle an error right now. Worst case should be missed + * synchronisation leading to rendering corruption. + */ + mutex_lock(&resv->lock.base); + if (obj->base.write_domain) + reservation_object_add_excl_fence(resv, &req->fence); + else if (reservation_object_reserve_shared(resv) == 0) + reservation_object_add_shared_fence(resv, &req->fence); + mutex_unlock(&resv->lock.base); +} + void i915_gem_execbuffer_move_to_active(struct list_head *vmas, struct drm_i915_gem_request *req) @@ -1106,6 +1131,7 @@ i915_gem_execbuffer_move_to_active(struct list_head *vmas, obj->base.read_domains = obj->base.pending_read_domains; i915_vma_move_to_active(vma, req); + eb_export_fence(obj, req); if (obj->base.write_domain) { i915_gem_request_assign(&obj->last_write_req, req); -- 2.8.1 _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
