2023-09-15 13:33:15

by Larysa Zaremba

Subject: [PATCH bpf-next v2] bpf: Allow to use kfunc XDP hints and frags together

There is no fundamental reason, why multi-buffer XDP and XDP kfunc RX hints
cannot coexist in a single program.

Allow those features to be used together by modifying the flags condition
for dev-bound-only programs, segments are still prohibited for fully
offloaded programs, hence additional check.

Suggested-by: Stanislav Fomichev <[email protected]>
Link: https://lore.kernel.org/bpf/CAKH8qBuzgtJj=OKMdsxEkyML36VsAuZpcrsXcyqjdKXSJCBq=Q@mail.gmail.com/
Reviewed-by: Maciej Fijalkowski <[email protected]>
Signed-off-by: Larysa Zaremba <[email protected]>
---
kernel/bpf/offload.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/kernel/bpf/offload.c b/kernel/bpf/offload.c
index ee35f33a96d1..9d8e508c9b86 100644
--- a/kernel/bpf/offload.c
+++ b/kernel/bpf/offload.c
@@ -232,7 +232,14 @@ int bpf_prog_dev_bound_init(struct bpf_prog *prog, union bpf_attr *attr)
attr->prog_type != BPF_PROG_TYPE_XDP)
return -EINVAL;

- if (attr->prog_flags & ~BPF_F_XDP_DEV_BOUND_ONLY)
+ if (attr->prog_flags & ~(BPF_F_XDP_DEV_BOUND_ONLY | BPF_F_XDP_HAS_FRAGS))
+ return -EINVAL;
+
+ /* Frags are allowed only if program is dev-bound-only, but not
+ * if it is requesting bpf offload.
+ */
+ if (attr->prog_flags & BPF_F_XDP_HAS_FRAGS &&
+ !(attr->prog_flags & BPF_F_XDP_DEV_BOUND_ONLY))
return -EINVAL;

if (attr->prog_type == BPF_PROG_TYPE_SCHED_CLS &&
--
2.41.0

2023-09-15 18:57:03

by Stanislav Fomichev

Subject: Re: [PATCH bpf-next v2] bpf: Allow to use kfunc XDP hints and frags together

On Fri, Sep 15, 2023 at 1:45 AM Larysa Zaremba <[email protected]> wrote:
>
> There is no fundamental reason, why multi-buffer XDP and XDP kfunc RX hints
> cannot coexist in a single program.
>
> Allow those features to be used together by modifying the flags condition
> for dev-bound-only programs, segments are still prohibited for fully
> offloaded programs, hence additional check.
>
> Suggested-by: Stanislav Fomichev <[email protected]>
> Link: https://lore.kernel.org/bpf/CAKH8qBuzgtJj=OKMdsxEkyML36VsAuZpcrsXcyqjdKXSJCBq=Q@mail.gmail.com/
> Reviewed-by: Maciej Fijalkowski <[email protected]>
> Signed-off-by: Larysa Zaremba <[email protected]>

Acked-by: Stanislav Fomichev <[email protected]>

Thank you!

> ---
> kernel/bpf/offload.c | 9 ++++++++-
> 1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/kernel/bpf/offload.c b/kernel/bpf/offload.c
> index ee35f33a96d1..9d8e508c9b86 100644
> --- a/kernel/bpf/offload.c
> +++ b/kernel/bpf/offload.c
> @@ -232,7 +232,14 @@ int bpf_prog_dev_bound_init(struct bpf_prog *prog, union bpf_attr *attr)
> attr->prog_type != BPF_PROG_TYPE_XDP)
> return -EINVAL;
>
> - if (attr->prog_flags & ~BPF_F_XDP_DEV_BOUND_ONLY)
> + if (attr->prog_flags & ~(BPF_F_XDP_DEV_BOUND_ONLY | BPF_F_XDP_HAS_FRAGS))
> + return -EINVAL;
> +
> + /* Frags are allowed only if program is dev-bound-only, but not
> + * if it is requesting bpf offload.
> + */
> + if (attr->prog_flags & BPF_F_XDP_HAS_FRAGS &&
> + !(attr->prog_flags & BPF_F_XDP_DEV_BOUND_ONLY))
> return -EINVAL;
>
> if (attr->prog_type == BPF_PROG_TYPE_SCHED_CLS &&
> --
> 2.41.0
>

2023-09-15 19:37:10

by patchwork-bot+netdevbpf

Subject: Re: [PATCH bpf-next v2] bpf: Allow to use kfunc XDP hints and frags together

Hello:

This patch was applied to bpf/bpf-next.git (master)
by Martin KaFai Lau <[email protected]>:

On Fri, 15 Sep 2023 10:39:10 +0200 you wrote:
> There is no fundamental reason, why multi-buffer XDP and XDP kfunc RX hints
> cannot coexist in a single program.
>
> Allow those features to be used together by modifying the flags condition
> for dev-bound-only programs, segments are still prohibited for fully
> offloaded programs, hence additional check.
>
> [...]

Here is the summary with links:
- [bpf-next,v2] bpf: Allow to use kfunc XDP hints and frags together
https://git.kernel.org/bpf/bpf-next/c/9b2b86332a9b

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

2023-09-15 21:49:31

by Martin KaFai Lau

Subject: Re: [PATCH bpf-next v2] bpf: Allow to use kfunc XDP hints and frags together

On 9/15/23 1:39 AM, Larysa Zaremba wrote:
> There is no fundamental reason, why multi-buffer XDP and XDP kfunc RX hints
> cannot coexist in a single program.
>
> Allow those features to be used together by modifying the flags condition
> for dev-bound-only programs, segments are still prohibited for fully
> offloaded programs, hence additional check.

Applied. Please do follow up with a test. Thanks.