On 07/10/2016 10:46, Chris Wilson wrote:
In forthcoming patches, we want to be able to dynamically allocate the
wait_queue_t used whilst awaiting. This is more convenient if we extend
the i915_sw_fence_await_sw_fence() to perform the allocation for us if
we pass in a gfp mask as an alternative than a preallocated struct.
Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>
---
drivers/gpu/drm/i915/i915_sw_fence.c | 40 ++++++++++++++++++++++++++++++++----
drivers/gpu/drm/i915/i915_sw_fence.h | 8 ++++++++
2 files changed, 44 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_sw_fence.c b/drivers/gpu/drm/i915/i915_sw_fence.c
index 1e5cbc585ca2..dfb59dced0ce 100644
--- a/drivers/gpu/drm/i915/i915_sw_fence.c
+++ b/drivers/gpu/drm/i915/i915_sw_fence.c
@@ -13,6 +13,8 @@
#include "i915_sw_fence.h"
+#define I915_SW_FENCE_FLAG_ALLOC BIT(0)
+
You collide with WQ_FLAG_EXCLUSIVE here, so I assume i915 will have
complete control of the wq in question?
static DEFINE_SPINLOCK(i915_sw_fence_lock);
static int __i915_sw_fence_notify(struct i915_sw_fence *fence,
@@ -135,6 +137,8 @@ static int i915_sw_fence_wake(wait_queue_t *wq, unsigned mode, int flags, void *
list_del(&wq->task_list);
__i915_sw_fence_complete(wq->private, key);
i915_sw_fence_put(wq->private);
+ if (wq->flags & I915_SW_FENCE_FLAG_ALLOC)
+ kfree(wq);
return 0;
}
@@ -192,9 +196,9 @@ static bool i915_sw_fence_check_if_after(struct i915_sw_fence *fence,
return err;
}
-int i915_sw_fence_await_sw_fence(struct i915_sw_fence *fence,
- struct i915_sw_fence *signaler,
- wait_queue_t *wq)
+static int __i915_sw_fence_await_sw_fence(struct i915_sw_fence *fence,
+ struct i915_sw_fence *signaler,
+ wait_queue_t *wq, gfp_t gfp)
{
unsigned long flags;
int pending;
@@ -206,8 +210,22 @@ int i915_sw_fence_await_sw_fence(struct i915_sw_fence *fence,
if (unlikely(i915_sw_fence_check_if_after(fence, signaler)))
return -EINVAL;
+ pending = 0;
+ if (!wq) {
+ wq = kmalloc(sizeof(*wq), gfp);
+ if (!wq) {
+ if (!gfpflags_allow_blocking(gfp))
+ return -ENOMEM;
+
+ i915_sw_fence_wait(signaler);
This looks like a strange API, unless I am missing something - it
normally sets things up for waiting, unless the allocation fails when it
actually does the wait?
+ return 0;
+ }
+
+ pending |= I915_SW_FENCE_FLAG_ALLOC;
Why is this stored in pending? Just because it is around as re-used?
+ }
+
INIT_LIST_HEAD(&wq->task_list);
- wq->flags = 0;
+ wq->flags = pending;
wq->func = i915_sw_fence_wake;
wq->private = i915_sw_fence_get(fence);
@@ -226,6 +244,20 @@ int i915_sw_fence_await_sw_fence(struct i915_sw_fence *fence,
return pending;
}
+int i915_sw_fence_await_sw_fence(struct i915_sw_fence *fence,
+ struct i915_sw_fence *signaler,
+ wait_queue_t *wq)
+{
+ return __i915_sw_fence_await_sw_fence(fence, signaler, wq, 0);
+}
+
+int i915_sw_fence_await_sw_fence_gfp(struct i915_sw_fence *fence,
+ struct i915_sw_fence *signaler,
+ gfp_t gfp)
+{
+ return __i915_sw_fence_await_sw_fence(fence, signaler, NULL, gfp);
+}
+
struct dma_fence_cb {
struct fence_cb base;
struct i915_sw_fence *fence;
diff --git a/drivers/gpu/drm/i915/i915_sw_fence.h b/drivers/gpu/drm/i915/i915_sw_fence.h
index 373141602ca4..5861c69f24d4 100644
--- a/drivers/gpu/drm/i915/i915_sw_fence.h
+++ b/drivers/gpu/drm/i915/i915_sw_fence.h
@@ -46,6 +46,9 @@ void i915_sw_fence_commit(struct i915_sw_fence *fence);
int i915_sw_fence_await_sw_fence(struct i915_sw_fence *fence,
struct i915_sw_fence *after,
wait_queue_t *wq);
+int i915_sw_fence_await_sw_fence_gfp(struct i915_sw_fence *fence,
+ struct i915_sw_fence *after,
+ gfp_t gfp);
int i915_sw_fence_await_dma_fence(struct i915_sw_fence *fence,
struct fence *dma,
unsigned long timeout,
@@ -62,4 +65,9 @@ static inline bool i915_sw_fence_done(const struct i915_sw_fence *fence)
return atomic_read(&fence->pending) < 0;
}
+static inline void i915_sw_fence_wait(struct i915_sw_fence *fence)
+{
+ wait_event(fence->wait, i915_sw_fence_done(fence));
+}
+
#endif /* _I915_SW_FENCE_H_ */
Regards,
Tvrtko
_______________________________________________
Intel-gfx mailing list
Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
