Ping!
Any more comments or can I get an rb on this? Sorry for the hurry, but I
want to get this our of my feet.
Regards,
Christian.
Silence is golden. Except when you have kids or wait for code review,
then silence is suspicious.
On 27.10.2015 17:04, Christian König wrote:
> From: Christian König <christian.koenig at amd.com>
>
> Waiting for the first fence in an array of fences to signal.
>
> This is useful for device driver specific resource managers
> and also Vulkan needs something similar.
>
> v2: more parameter checks, handling for timeout==0,
> remove NULL entry support, better callback removal.
>
> Signed-off-by: Christian König <christian.koenig at amd.com>
> Reviewed-by: Alex Deucher <alexander.deucher at amd.com>
> ---
> drivers/dma-buf/fence.c | 98
> +++++++++++++++++++++++++++++++++++++++++++++++++
> include/linux/fence.h | 3 +-
> 2 files changed, 100 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/dma-buf/fence.c b/drivers/dma-buf/fence.c
> index 50ef8bd..7b05dbe 100644
> --- a/drivers/dma-buf/fence.c
> +++ b/drivers/dma-buf/fence.c
> @@ -397,6 +397,104 @@ out:
> }
> EXPORT_SYMBOL(fence_default_wait);
>
> +static bool
> +fence_test_signaled_any(struct fence **fences, uint32_t count)
> +{
> + int i;
> +
> + for (i = 0; i < count; ++i) {
> + struct fence *fence = fences[i];
> + if (test_bit(FENCE_FLAG_SIGNALED_BIT, &fence->flags))
> + return true;
> + }
> + return false;
> +}
> +
> +/**
> + * fence_wait_any_timeout - sleep until any fence gets signaled
> + * or until timeout elapses
> + * @fences: [in] array of fences to wait on
> + * @count: [in] number of fences to wait on
> + * @intr: [in] if true, do an interruptible wait
> + * @timeout: [in] timeout value in jiffies, or MAX_SCHEDULE_TIMEOUT
> + *
> + * Returns -EINVAL on custom fence wait implementation, -ERESTARTSYS if
> + * interrupted, 0 if the wait timed out, or the remaining timeout in jiffies
> + * on success.
> + *
> + * Synchronous waits for the first fence in the array to be signaled. The
> + * caller needs to hold a reference to all fences in the array, otherwise a
> + * fence might be freed before return, resulting in undefined behavior.
> + */
> +signed long
> +fence_wait_any_timeout(struct fence **fences, uint32_t count,
> + bool intr, signed long timeout)
> +{
> + struct default_wait_cb *cb;
> + signed long ret = timeout;
> + unsigned i;
> +
> + if (WARN_ON(!fences || !count || timeout < 0))
> + return -EINVAL;
> +
> + if (timeout == 0) {
> + for (i = 0; i < count; ++i)
> + if (fence_is_signaled(fences[i]))
> + return 1;
> +
> + return 0;
> + }
> +
> + cb = kcalloc(count, sizeof(struct default_wait_cb), GFP_KERNEL);
> + if (cb == NULL) {
> + ret = -ENOMEM;
> + goto err_free_cb;
> + }
> +
> + for (i = 0; i < count; ++i) {
> + struct fence *fence = fences[i];
> +
> + if (fence->ops->wait != fence_default_wait) {
> + ret = -EINVAL;
> + goto fence_rm_cb;
> + }
> +
> + cb[i].task = current;
> + if (fence_add_callback(fence, &cb[i].base,
> + fence_default_wait_cb)) {
> + /* This fence is already signaled */
> + goto fence_rm_cb;
> + }
> + }
> +
> + while (ret > 0) {
> + if (intr)
> + set_current_state(TASK_INTERRUPTIBLE);
> + else
> + set_current_state(TASK_UNINTERRUPTIBLE);
> +
> + if (fence_test_signaled_any(fences, count))
> + break;
> +
> + ret = schedule_timeout(ret);
> +
> + if (ret > 0 && intr && signal_pending(current))
> + ret = -ERESTARTSYS;
> + }
> +
> + __set_current_state(TASK_RUNNING);
> +
> +fence_rm_cb:
> + while (i-- > 0)
> + fence_remove_callback(fences[i], &cb[i].base);
> +
> +err_free_cb:
> + kfree(cb);
> +
> + return ret;
> +}
> +EXPORT_SYMBOL(fence_wait_any_timeout);
> +
> /**
> * fence_init - Initialize a custom fence.
> * @fence: [in] the fence to initialize
> diff --git a/include/linux/fence.h b/include/linux/fence.h
> index ddc0f26..bb52201 100644
> --- a/include/linux/fence.h
> +++ b/include/linux/fence.h
> @@ -321,7 +321,8 @@ static inline struct fence *fence_later(struct fence *f1,
> struct fence *f2)
> }
>
> signed long fence_wait_timeout(struct fence *, bool intr, signed long
> timeout);
> -
> +signed long fence_wait_any_timeout(struct fence **fences, uint32_t count,
> + bool intr, signed long timeout);
>
> /**
> * fence_wait - sleep until the fence gets signaled
