Re: [PATCH] drm/amdkfd: Remove vla

2018-04-10 Thread Laura Abbott

On 04/09/2018 11:38 PM, Christian König wrote:

Am 09.04.2018 um 23:06 schrieb Laura Abbott:

There's an ongoing effort to remove VLAs[1] from the kernel to eventually
turn on -Wvla. The single VLA usage in the amdkfd driver is actually
constant across all current platforms.


Actually that isn't correct.

Could be that we haven't upstreamed KFD support for them, but Vega10 have a 
different interrupt ring entry size and so would cause the error message here.


Switch to a constant size array
instead.


I would say to just make make the array bigger.

Regards,
Christian.



What array size would accommodate future chips?



[1] https://lkml.org/lkml/2018/3/7/621

Signed-off-by: Laura Abbott 
---
  drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c | 8 +---
  1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c 
b/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
index 035c351f47c5..c9863858f343 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
@@ -139,10 +139,12 @@ static void interrupt_wq(struct work_struct *work)
  {
  struct kfd_dev *dev = container_of(work, struct kfd_dev,
  interrupt_work);
+    uint32_t ih_ring_entry[4];
-    uint32_t ih_ring_entry[DIV_ROUND_UP(
-    dev->device_info->ih_ring_entry_size,
-    sizeof(uint32_t))];
+    if (dev->device_info->ih_ring_entry_size > (4 * sizeof(uint32_t))) {
+    dev_err(kfd_chardev(), "Ring entry too small\n");
+    return;
+    }
  while (dequeue_ih_ring_entry(dev, ih_ring_entry))
  dev->device_info->event_interrupt_class->interrupt_wq(dev,






Re: [PATCH] drm/amdkfd: Remove vla

2018-04-10 Thread Felix Kuehling
Thanks Christian for catching that. I'm working on a patch series to
upstream Vega10 support, about 95% done. It will add this ASIC info for
Vega10:

static const struct kfd_device_info vega10_device_info = {
.asic_family = CHIP_VEGA10,
.max_pasid_bits = 16,
.max_no_of_hqd  = 24,
.doorbell_size  = 8,
.ih_ring_entry_size = 8 * sizeof(uint32_t), /* !!! IH ring entry size 
is bigger on Vega10 !!! */
.event_interrupt_class = &event_interrupt_class_v9,
.num_of_watch_points = 4,
.mqd_size_aligned = MQD_SIZE_ALIGNED,
.supports_cwsr = true,
.needs_iommu_device = false,
.needs_pci_atomics = false,
};

If you change it to uint32_t ih_ring_entry[8] and update the check, it
should be reasonably future proof.

Regards,
  Felix


On 2018-04-10 02:38 AM, Christian König wrote:
> Am 09.04.2018 um 23:06 schrieb Laura Abbott:
>> There's an ongoing effort to remove VLAs[1] from the kernel to
>> eventually
>> turn on -Wvla. The single VLA usage in the amdkfd driver is actually
>> constant across all current platforms.
>
> Actually that isn't correct.
>
> Could be that we haven't upstreamed KFD support for them, but Vega10
> have a different interrupt ring entry size and so would cause the
> error message here.
>
>> Switch to a constant size array
>> instead.
>
> I would say to just make make the array bigger.
>
> Regards,
> Christian.
>
>>
>> [1] https://lkml.org/lkml/2018/3/7/621
>>
>> Signed-off-by: Laura Abbott 
>> ---
>>   drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c | 8 +---
>>   1 file changed, 5 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
>> b/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
>> index 035c351f47c5..c9863858f343 100644
>> --- a/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
>> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
>> @@ -139,10 +139,12 @@ static void interrupt_wq(struct work_struct *work)
>>   {
>>   struct kfd_dev *dev = container_of(work, struct kfd_dev,
>>   interrupt_work);
>> +    uint32_t ih_ring_entry[4];
>>   -    uint32_t ih_ring_entry[DIV_ROUND_UP(
>> -    dev->device_info->ih_ring_entry_size,
>> -    sizeof(uint32_t))];
>> +    if (dev->device_info->ih_ring_entry_size > (4 *
>> sizeof(uint32_t))) {
>> +    dev_err(kfd_chardev(), "Ring entry too small\n");
>> +    return;
>> +    }
>>     while (dequeue_ih_ring_entry(dev, ih_ring_entry))
>>   dev->device_info->event_interrupt_class->interrupt_wq(dev,
>
> ___
> amd-gfx mailing list
> amd-...@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/amd-gfx



Re: [PATCH] drm/amdkfd: Remove vla

2018-04-09 Thread Christian König

Am 09.04.2018 um 23:06 schrieb Laura Abbott:

There's an ongoing effort to remove VLAs[1] from the kernel to eventually
turn on -Wvla. The single VLA usage in the amdkfd driver is actually
constant across all current platforms.


Actually that isn't correct.

Could be that we haven't upstreamed KFD support for them, but Vega10 
have a different interrupt ring entry size and so would cause the error 
message here.



Switch to a constant size array
instead.


I would say to just make make the array bigger.

Regards,
Christian.



[1] https://lkml.org/lkml/2018/3/7/621

Signed-off-by: Laura Abbott 
---
  drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c | 8 +---
  1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c 
b/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
index 035c351f47c5..c9863858f343 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
@@ -139,10 +139,12 @@ static void interrupt_wq(struct work_struct *work)
  {
struct kfd_dev *dev = container_of(work, struct kfd_dev,
interrupt_work);
+   uint32_t ih_ring_entry[4];
  
-	uint32_t ih_ring_entry[DIV_ROUND_UP(

-   dev->device_info->ih_ring_entry_size,
-   sizeof(uint32_t))];
+   if (dev->device_info->ih_ring_entry_size > (4 * sizeof(uint32_t))) {
+   dev_err(kfd_chardev(), "Ring entry too small\n");
+   return;
+   }
  
  	while (dequeue_ih_ring_entry(dev, ih_ring_entry))

dev->device_info->event_interrupt_class->interrupt_wq(dev,




[PATCH] drm/amdkfd: Remove vla

2018-04-09 Thread Laura Abbott
There's an ongoing effort to remove VLAs[1] from the kernel to eventually
turn on -Wvla. The single VLA usage in the amdkfd driver is actually
constant across all current platforms. Switch to a constant size array
instead.

[1] https://lkml.org/lkml/2018/3/7/621

Signed-off-by: Laura Abbott 
---
 drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c | 8 +---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c 
b/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
index 035c351f47c5..c9863858f343 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
@@ -139,10 +139,12 @@ static void interrupt_wq(struct work_struct *work)
 {
struct kfd_dev *dev = container_of(work, struct kfd_dev,
interrupt_work);
+   uint32_t ih_ring_entry[4];
 
-   uint32_t ih_ring_entry[DIV_ROUND_UP(
-   dev->device_info->ih_ring_entry_size,
-   sizeof(uint32_t))];
+   if (dev->device_info->ih_ring_entry_size > (4 * sizeof(uint32_t))) {
+   dev_err(kfd_chardev(), "Ring entry too small\n");
+   return;
+   }
 
while (dequeue_ih_ring_entry(dev, ih_ring_entry))
dev->device_info->event_interrupt_class->interrupt_wq(dev,
-- 
2.14.3