| Message ID | 1463333573-25112-15-git-send-email-zhi.a.wang@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, May 16, 2016 at 01:32:52AM +0800, Zhi Wang wrote: > Factor out and expose fence stealing functionality for GVT-g. GVT-g > will use i915_find_fence_reg() to find a free/unpin fence register > and use i915_steal_fence() to steal it. No. This code cannot be exported as is (the code makes presumptions that the caller will carefully control the reference). And there is nothing to tell us what you need it for. -Chris
I see. How about merging this function into i915_find_fence_reg()? -----Original Message----- From: Chris Wilson [mailto:chris@chris-wilson.co.uk] Sent: Monday, May 16, 2016 7:58 AM To: Wang, Zhi A <zhi.a.wang@intel.com> Cc: intel-gfx@lists.freedesktop.org; Gordon, David S <david.s.gordon@intel.com>; joonas.lahtinen@linux.intel.com; Tian, Kevin <kevin.tian@intel.com>; Lv, Zhiyuan <zhiyuan.lv@intel.com> Subject: Re: [Intel-gfx] [PATCH 14/15] drm/i915: Factor out and expose i915_steal_fence() On Mon, May 16, 2016 at 01:32:52AM +0800, Zhi Wang wrote: > Factor out and expose fence stealing functionality for GVT-g. GVT-g > will use i915_find_fence_reg() to find a free/unpin fence register and > use i915_steal_fence() to steal it. No. This code cannot be exported as is (the code makes presumptions that the caller will carefully control the reference). And there is nothing to tell us what you need it for. -Chris -- Chris Wilson, Intel Open Source Technology Centre
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index ae1149c..96d9abd 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -3376,6 +3376,7 @@ i915_gem_object_ggtt_unpin(struct drm_i915_gem_object *obj) /* i915_gem_fence.c */ int __must_check i915_gem_object_get_fence(struct drm_i915_gem_object *obj); int __must_check i915_gem_object_put_fence(struct drm_i915_gem_object *obj); +int i915_steal_fence(struct drm_i915_fence_reg *reg); bool i915_gem_object_pin_fence(struct drm_i915_gem_object *obj); void i915_gem_object_unpin_fence(struct drm_i915_gem_object *obj); diff --git a/drivers/gpu/drm/i915/i915_gem_fence.c b/drivers/gpu/drm/i915/i915_gem_fence.c index a2b938e..e790d7b 100644 --- a/drivers/gpu/drm/i915/i915_gem_fence.c +++ b/drivers/gpu/drm/i915/i915_gem_fence.c @@ -346,6 +346,33 @@ deadlock: } /** + * i915_steal_fence - steal a fence from a GEM object + * @reg: the fence register to be stolen + * + * Returns: + * + * 0 on success, negative error code on failure. + */ +int i915_steal_fence(struct drm_i915_fence_reg *reg) +{ + int ret; + + if (WARN_ON(reg->pin_count)) + return -EBUSY; + + if (reg->obj) { + struct drm_i915_gem_object *old = reg->obj; + + ret = i915_gem_object_wait_fence(old); + if (ret) + return ret; + + i915_gem_object_fence_lost(old); + } + return 0; +} + +/** * i915_gem_object_get_fence - set up fencing for an object * @obj: object to map through a fence reg * @@ -397,15 +424,9 @@ i915_gem_object_get_fence(struct drm_i915_gem_object *obj) if (IS_ERR(reg)) return PTR_ERR(reg); - if (reg->obj) { - struct drm_i915_gem_object *old = reg->obj; - - ret = i915_gem_object_wait_fence(old); - if (ret) - return ret; - - i915_gem_object_fence_lost(old); - } + ret = i915_steal_fence(reg); + if (ret) + return ret; } else return 0;
Factor out and expose fence stealing functionality for GVT-g. GVT-g will use i915_find_fence_reg() to find a free/unpin fence register and use i915_steal_fence() to steal it. Signed-off-by: Zhi Wang <zhi.a.wang@intel.com> --- drivers/gpu/drm/i915/i915_drv.h | 1 + drivers/gpu/drm/i915/i915_gem_fence.c | 39 +++++++++++++++++++++++++++-------- 2 files changed, 31 insertions(+), 9 deletions(-)