Re: [PATCH 2/3] drm/panthor: Make sure the tiler initial/max chunks are consistent
On Thu, 25 Apr 2024 11:43:39 +0100
Steven Price wrote:
> On 25/04/2024 10:28, Steven Price wrote:
> > On 25/04/2024 08:18, Boris Brezillon wrote:
> >> It doesn't make sense to have a maximum number of chunks smaller than
> >> the initial number of chunks attached to the context.
> >>
> >> Fix the uAPI header to reflect the new constraint, and mention the
> >> undocumented "initial_chunk_count > 0" constraint while at it.
> >>
> >> Fixes: 9cca48fa4f89 ("drm/panthor: Add the heap logical block")
> >> Signed-off-by: Boris Brezillon
> >
> > Reviewed-by: Steven Price
>
> Ok, I'll take that back... I've rebased (and fixed up all the out of
> tree patches) and this doesn't work when I actually test it!
>
> >
> >> ---
> >> drivers/gpu/drm/panthor/panthor_heap.c | 3 +++
> >> include/uapi/drm/panthor_drm.h | 8 ++--
> >> 2 files changed, 9 insertions(+), 2 deletions(-)
> >>
> >> diff --git a/drivers/gpu/drm/panthor/panthor_heap.c
> >> b/drivers/gpu/drm/panthor/panthor_heap.c
> >> index 143fa35f2e74..8728c9bb76e4 100644
> >> --- a/drivers/gpu/drm/panthor/panthor_heap.c
> >> +++ b/drivers/gpu/drm/panthor/panthor_heap.c
> >> @@ -281,6 +281,9 @@ int panthor_heap_create(struct panthor_heap_pool *pool,
> >>if (initial_chunk_count == 0)
> >>return -EINVAL;
> >>
> >> + if (initial_chunk_count < max_chunks)
>
> This should be initial_chunk_count > max_chunks. Otherwise you're
> requiring the initial chunk count to be equal *or greater* than the max
> chunks which makes no sense!
Damn it, here's what happens when you think your changes are too
trivial to be wrong...
But I swear I would have tested the whole thing before pushing to
drm-misc. :P
Re: [PATCH 2/3] drm/panthor: Make sure the tiler initial/max chunks are consistent
On 25/04/2024 10:28, Steven Price wrote:
> On 25/04/2024 08:18, Boris Brezillon wrote:
>> It doesn't make sense to have a maximum number of chunks smaller than
>> the initial number of chunks attached to the context.
>>
>> Fix the uAPI header to reflect the new constraint, and mention the
>> undocumented "initial_chunk_count > 0" constraint while at it.
>>
>> Fixes: 9cca48fa4f89 ("drm/panthor: Add the heap logical block")
>> Signed-off-by: Boris Brezillon
>
> Reviewed-by: Steven Price
Ok, I'll take that back... I've rebased (and fixed up all the out of
tree patches) and this doesn't work when I actually test it!
>
>> ---
>> drivers/gpu/drm/panthor/panthor_heap.c | 3 +++
>> include/uapi/drm/panthor_drm.h | 8 ++--
>> 2 files changed, 9 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/panthor/panthor_heap.c
>> b/drivers/gpu/drm/panthor/panthor_heap.c
>> index 143fa35f2e74..8728c9bb76e4 100644
>> --- a/drivers/gpu/drm/panthor/panthor_heap.c
>> +++ b/drivers/gpu/drm/panthor/panthor_heap.c
>> @@ -281,6 +281,9 @@ int panthor_heap_create(struct panthor_heap_pool *pool,
>> if (initial_chunk_count == 0)
>> return -EINVAL;
>>
>> +if (initial_chunk_count < max_chunks)
This should be initial_chunk_count > max_chunks. Otherwise you're
requiring the initial chunk count to be equal *or greater* than the max
chunks which makes no sense!
Steve
>> +return -EINVAL;
>> +
>> if (hweight32(chunk_size) != 1 ||
>> chunk_size < SZ_256K || chunk_size > SZ_2M)
>> return -EINVAL;
>> diff --git a/include/uapi/drm/panthor_drm.h b/include/uapi/drm/panthor_drm.h
>> index dadb05ab1235..5db80a0682d5 100644
>> --- a/include/uapi/drm/panthor_drm.h
>> +++ b/include/uapi/drm/panthor_drm.h
>> @@ -895,13 +895,17 @@ struct drm_panthor_tiler_heap_create {
>> /** @vm_id: VM ID the tiler heap should be mapped to */
>> __u32 vm_id;
>>
>> -/** @initial_chunk_count: Initial number of chunks to allocate. */
>> +/** @initial_chunk_count: Initial number of chunks to allocate. Must be
>> at least one. */
>> __u32 initial_chunk_count;
>>
>> /** @chunk_size: Chunk size. Must be a power of two at least 256KB
>> large. */
>> __u32 chunk_size;
>>
>> -/** @max_chunks: Maximum number of chunks that can be allocated. */
>> +/**
>> + * @max_chunks: Maximum number of chunks that can be allocated.
>> + *
>> + * Must be at least @initial_chunk_count.
>> + */
>> __u32 max_chunks;
>>
>> /**
>
Re: [PATCH 2/3] drm/panthor: Make sure the tiler initial/max chunks are consistent
On 25/04/2024 08:18, Boris Brezillon wrote:
> It doesn't make sense to have a maximum number of chunks smaller than
> the initial number of chunks attached to the context.
>
> Fix the uAPI header to reflect the new constraint, and mention the
> undocumented "initial_chunk_count > 0" constraint while at it.
>
> Fixes: 9cca48fa4f89 ("drm/panthor: Add the heap logical block")
> Signed-off-by: Boris Brezillon
Reviewed-by: Steven Price
> ---
> drivers/gpu/drm/panthor/panthor_heap.c | 3 +++
> include/uapi/drm/panthor_drm.h | 8 ++--
> 2 files changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/panthor/panthor_heap.c
> b/drivers/gpu/drm/panthor/panthor_heap.c
> index 143fa35f2e74..8728c9bb76e4 100644
> --- a/drivers/gpu/drm/panthor/panthor_heap.c
> +++ b/drivers/gpu/drm/panthor/panthor_heap.c
> @@ -281,6 +281,9 @@ int panthor_heap_create(struct panthor_heap_pool *pool,
> if (initial_chunk_count == 0)
> return -EINVAL;
>
> + if (initial_chunk_count < max_chunks)
> + return -EINVAL;
> +
> if (hweight32(chunk_size) != 1 ||
> chunk_size < SZ_256K || chunk_size > SZ_2M)
> return -EINVAL;
> diff --git a/include/uapi/drm/panthor_drm.h b/include/uapi/drm/panthor_drm.h
> index dadb05ab1235..5db80a0682d5 100644
> --- a/include/uapi/drm/panthor_drm.h
> +++ b/include/uapi/drm/panthor_drm.h
> @@ -895,13 +895,17 @@ struct drm_panthor_tiler_heap_create {
> /** @vm_id: VM ID the tiler heap should be mapped to */
> __u32 vm_id;
>
> - /** @initial_chunk_count: Initial number of chunks to allocate. */
> + /** @initial_chunk_count: Initial number of chunks to allocate. Must be
> at least one. */
> __u32 initial_chunk_count;
>
> /** @chunk_size: Chunk size. Must be a power of two at least 256KB
> large. */
> __u32 chunk_size;
>
> - /** @max_chunks: Maximum number of chunks that can be allocated. */
> + /**
> + * @max_chunks: Maximum number of chunks that can be allocated.
> + *
> + * Must be at least @initial_chunk_count.
> + */
> __u32 max_chunks;
>
> /**
[PATCH 2/3] drm/panthor: Make sure the tiler initial/max chunks are consistent
It doesn't make sense to have a maximum number of chunks smaller than
the initial number of chunks attached to the context.
Fix the uAPI header to reflect the new constraint, and mention the
undocumented "initial_chunk_count > 0" constraint while at it.
Fixes: 9cca48fa4f89 ("drm/panthor: Add the heap logical block")
Signed-off-by: Boris Brezillon
---
drivers/gpu/drm/panthor/panthor_heap.c | 3 +++
include/uapi/drm/panthor_drm.h | 8 ++--
2 files changed, 9 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/panthor/panthor_heap.c
b/drivers/gpu/drm/panthor/panthor_heap.c
index 143fa35f2e74..8728c9bb76e4 100644
--- a/drivers/gpu/drm/panthor/panthor_heap.c
+++ b/drivers/gpu/drm/panthor/panthor_heap.c
@@ -281,6 +281,9 @@ int panthor_heap_create(struct panthor_heap_pool *pool,
if (initial_chunk_count == 0)
return -EINVAL;
+ if (initial_chunk_count < max_chunks)
+ return -EINVAL;
+
if (hweight32(chunk_size) != 1 ||
chunk_size < SZ_256K || chunk_size > SZ_2M)
return -EINVAL;
diff --git a/include/uapi/drm/panthor_drm.h b/include/uapi/drm/panthor_drm.h
index dadb05ab1235..5db80a0682d5 100644
--- a/include/uapi/drm/panthor_drm.h
+++ b/include/uapi/drm/panthor_drm.h
@@ -895,13 +895,17 @@ struct drm_panthor_tiler_heap_create {
/** @vm_id: VM ID the tiler heap should be mapped to */
__u32 vm_id;
- /** @initial_chunk_count: Initial number of chunks to allocate. */
+ /** @initial_chunk_count: Initial number of chunks to allocate. Must be
at least one. */
__u32 initial_chunk_count;
/** @chunk_size: Chunk size. Must be a power of two at least 256KB
large. */
__u32 chunk_size;
- /** @max_chunks: Maximum number of chunks that can be allocated. */
+ /**
+* @max_chunks: Maximum number of chunks that can be allocated.
+*
+* Must be at least @initial_chunk_count.
+*/
__u32 max_chunks;
/**
--
2.44.0
