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* [PATCH bpf-next v1] docs: bpf: map_array: specify BPF_MAP_TYPE_PERCPU_ARRAY value size limit
@ 2025-11-15  6:35 Alex Tran
  2025-11-25 22:40 ` patchwork-bot+netdevbpf
  0 siblings, 1 reply; 2+ messages in thread
From: Alex Tran @ 2025-11-15  6:35 UTC (permalink / raw)
  To: ast, daniel, andrii, corbet
  Cc: martin.lau, eddyz87, song, yonghong.song, john.fastabend, kpsingh,
	sdf, haoluo, jolsa, bpf, linux-doc, linux-kernel, Alex Tran

Specify value size limit for BPF_MAP_TYPE_PERCPU_ARRAY which
is PCPU_MIN_UNIT_SIZE (32 kb). In percpu allocator (mm: percpu), 
any request with a size greater than PCPU_MIN_UNIT_SIZE is rejected. 

Signed-off-by: Alex Tran <alex.t.tran@gmail.com>
---
 Documentation/bpf/map_array.rst | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/Documentation/bpf/map_array.rst b/Documentation/bpf/map_array.rst
index f2f51a53e8ae..fa56ff75190c 100644
--- a/Documentation/bpf/map_array.rst
+++ b/Documentation/bpf/map_array.rst
@@ -15,8 +15,9 @@ of constant size. The size of the array is defined in ``max_entries`` at
 creation time. All array elements are pre-allocated and zero initialized when
 created. ``BPF_MAP_TYPE_PERCPU_ARRAY`` uses a different memory region for each
 CPU whereas ``BPF_MAP_TYPE_ARRAY`` uses the same memory region. The value
-stored can be of any size, however, all array elements are aligned to 8
-bytes.
+stored can be of any size for ``BPF_MAP_TYPE_ARRAY`` and not more than
+``PCPU_MIN_UNIT_SIZE`` (32 kB) for ``BPF_MAP_TYPE_PERCPU_ARRAY``. All
+array elements are aligned to 8 bytes.
 
 Since kernel 5.5, memory mapping may be enabled for ``BPF_MAP_TYPE_ARRAY`` by
 setting the flag ``BPF_F_MMAPABLE``. The map definition is page-aligned and
-- 
2.51.0


^ permalink raw reply related	[flat|nested] 2+ messages in thread

* Re: [PATCH bpf-next v1] docs: bpf: map_array: specify BPF_MAP_TYPE_PERCPU_ARRAY value size limit
  2025-11-15  6:35 [PATCH bpf-next v1] docs: bpf: map_array: specify BPF_MAP_TYPE_PERCPU_ARRAY value size limit Alex Tran
@ 2025-11-25 22:40 ` patchwork-bot+netdevbpf
  0 siblings, 0 replies; 2+ messages in thread
From: patchwork-bot+netdevbpf @ 2025-11-25 22:40 UTC (permalink / raw)
  To: Alex Tran
  Cc: ast, daniel, andrii, corbet, martin.lau, eddyz87, song,
	yonghong.song, john.fastabend, kpsingh, sdf, haoluo, jolsa, bpf,
	linux-doc, linux-kernel

Hello:

This patch was applied to bpf/bpf-next.git (master)
by Andrii Nakryiko <andrii@kernel.org>:

On Fri, 14 Nov 2025 22:35:31 -0800 you wrote:
> Specify value size limit for BPF_MAP_TYPE_PERCPU_ARRAY which
> is PCPU_MIN_UNIT_SIZE (32 kb). In percpu allocator (mm: percpu),
> any request with a size greater than PCPU_MIN_UNIT_SIZE is rejected.
> 
> Signed-off-by: Alex Tran <alex.t.tran@gmail.com>
> ---
>  Documentation/bpf/map_array.rst | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)

Here is the summary with links:
  - [bpf-next,v1] docs: bpf: map_array: specify BPF_MAP_TYPE_PERCPU_ARRAY value size limit
    https://git.kernel.org/bpf/bpf-next/c/44bf4611827b

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html



^ permalink raw reply	[flat|nested] 2+ messages in thread

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2025-11-15  6:35 [PATCH bpf-next v1] docs: bpf: map_array: specify BPF_MAP_TYPE_PERCPU_ARRAY value size limit Alex Tran
2025-11-25 22:40 ` patchwork-bot+netdevbpf

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