[Intel-gfx] [RFC v4 02/14] drm/i915/vm_bind: Add __i915_sw_fence_await_reservation()

[Niranjana Vishwanathapura]

On Wed, Sep 21, 2022 at 10:06:48AM +0100, Tvrtko Ursulin wrote:
>
>On 21/09/2022 08:09, Niranjana Vishwanathapura wrote:
>>Add function __i915_sw_fence_await_reservation() for
>>asynchronous wait on a dma-resv object with specified
>>dma_resv_usage. This is required for async vma unbind
>>with vm_bind.
>>
>>Signed-off-by: Niranjana Vishwanathapura <niranjana.vishwanathapura at intel.com>
>>---
>>  drivers/gpu/drm/i915/i915_sw_fence.c | 25 ++++++++++++++++++-------
>>  drivers/gpu/drm/i915/i915_sw_fence.h |  7 ++++++-
>>  2 files changed, 24 insertions(+), 8 deletions(-)
>>
>>diff --git a/drivers/gpu/drm/i915/i915_sw_fence.c b/drivers/gpu/drm/i915/i915_sw_fence.c
>>index 6fc0d1b89690..0ce8f4efc1ed 100644
>>--- a/drivers/gpu/drm/i915/i915_sw_fence.c
>>+++ b/drivers/gpu/drm/i915/i915_sw_fence.c
>>@@ -569,12 +569,11 @@ int __i915_sw_fence_await_dma_fence(struct i915_sw_fence *fence,
>>  	return ret;
>>  }
>>-int i915_sw_fence_await_reservation(struct i915_sw_fence *fence,
>>-				    struct dma_resv *resv,
>>-				    const struct dma_fence_ops *exclude,
>>-				    bool write,
>>-				    unsigned long timeout,
>>-				    gfp_t gfp)
>>+int __i915_sw_fence_await_reservation(struct i915_sw_fence *fence,
>>+				      struct dma_resv *resv,
>>+				      enum dma_resv_usage usage,
>>+				      unsigned long timeout,
>>+				      gfp_t gfp)
>>  {
>>  	struct dma_resv_iter cursor;
>>  	struct dma_fence *f;
>>@@ -583,7 +582,7 @@ int i915_sw_fence_await_reservation(struct i915_sw_fence *fence,
>>  	debug_fence_assert(fence);
>>  	might_sleep_if(gfpflags_allow_blocking(gfp));
>>-	dma_resv_iter_begin(&cursor, resv, dma_resv_usage_rw(write));
>>+	dma_resv_iter_begin(&cursor, resv, usage);
>>  	dma_resv_for_each_fence_unlocked(&cursor, f) {
>>  		pending = i915_sw_fence_await_dma_fence(fence, f, timeout,
>>  							gfp);
>>@@ -598,6 +597,18 @@ int i915_sw_fence_await_reservation(struct i915_sw_fence *fence,
>>  	return ret;
>>  }
>>+int i915_sw_fence_await_reservation(struct i915_sw_fence *fence,
>>+				    struct dma_resv *resv,
>>+				    const struct dma_fence_ops *exclude,
>>+				    bool write,
>>+				    unsigned long timeout,
>>+				    gfp_t gfp)
>>+{
>>+	return __i915_sw_fence_await_reservation(fence, resv,
>>+						 dma_resv_usage_rw(write),
>>+						 timeout, gfp);
>>+}
>
>Drive by observation - it looked dodgy that you create a wrapper here 
>which ignores one function parameter.
>
>On a more detailed look it seems no callers actually use exclude and 
>it's even unused inside this function since 1b5bdf071e62 ("drm/i915: 
>use the new iterator in i915_sw_fence_await_reservation v3").
>
>So a cleanup patch before this one?
>

Thanks Tvrtko.
Yah, I noticed it, but did not want to fix that here.
Sure, will post a patch beforehand to fix that.

Niranjana

>Regards,
>
>Tvrtko
>
>
>>+
>>  #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
>>  #include "selftests/lib_sw_fence.c"
>>  #include "selftests/i915_sw_fence.c"
>>diff --git a/drivers/gpu/drm/i915/i915_sw_fence.h b/drivers/gpu/drm/i915/i915_sw_fence.h
>>index 619fc5a22f0c..3cf4b6e16f35 100644
>>--- a/drivers/gpu/drm/i915/i915_sw_fence.h
>>+++ b/drivers/gpu/drm/i915/i915_sw_fence.h
>>@@ -10,13 +10,13 @@
>>  #define _I915_SW_FENCE_H_
>>  #include <linux/dma-fence.h>
>>+#include <linux/dma-resv.h>
>>  #include <linux/gfp.h>
>>  #include <linux/kref.h>
>>  #include <linux/notifier.h> /* for NOTIFY_DONE */
>>  #include <linux/wait.h>
>>  struct completion;
>>-struct dma_resv;
>>  struct i915_sw_fence;
>>  enum i915_sw_fence_notify {
>>@@ -89,6 +89,11 @@ int i915_sw_fence_await_dma_fence(struct i915_sw_fence *fence,
>>  				  unsigned long timeout,
>>  				  gfp_t gfp);
>>+int __i915_sw_fence_await_reservation(struct i915_sw_fence *fence,
>>+				      struct dma_resv *resv,
>>+				      enum dma_resv_usage usage,
>>+				      unsigned long timeout,
>>+				      gfp_t gfp);
>>  int i915_sw_fence_await_reservation(struct i915_sw_fence *fence,
>>  				    struct dma_resv *resv,
>>  				    const struct dma_fence_ops *exclude,