From: Tariq Toukan <ttoukan.linux@gmail.com>
To: "Toke Høiland-Jørgensen" <toke@redhat.com>,
"Stanislav Fomichev" <sdf@google.com>,
"Tariq Toukan" <ttoukan.linux@gmail.com>
Cc: bpf@vger.kernel.org, ast@kernel.org, daniel@iogearbox.net,
andrii@kernel.org, martin.lau@linux.dev, song@kernel.org,
yhs@fb.com, john.fastabend@gmail.com, kpsingh@kernel.org,
haoluo@google.com, jolsa@kernel.org,
Saeed Mahameed <saeedm@nvidia.com>,
David Ahern <dsahern@gmail.com>, Jakub Kicinski <kuba@kernel.org>,
Willem de Bruijn <willemb@google.com>,
Jesper Dangaard Brouer <brouer@redhat.com>,
Anatoly Burakov <anatoly.burakov@intel.com>,
Alexander Lobakin <alexandr.lobakin@intel.com>,
Magnus Karlsson <magnus.karlsson@gmail.com>,
Maryam Tahhan <mtahhan@redhat.com>,
xdp-hints@xdp-project.net, netdev@vger.kernel.org
Subject: [xdp-hints] Re: [PATCH bpf-next v7 15/17] net/mlx5e: Introduce wrapper for xdp_buff
Date: Fri, 13 Jan 2023 22:53:47 +0200 [thread overview]
Message-ID: <d83f2193-3fb9-e30f-cfb0-f1098f039b67@gmail.com> (raw)
In-Reply-To: <87h6wvfmfa.fsf@toke.dk>
On 12/01/2023 23:55, Toke Høiland-Jørgensen wrote:
> Toke Høiland-Jørgensen <toke@redhat.com> writes:
>
>> Stanislav Fomichev <sdf@google.com> writes:
>>
>>> On Thu, Jan 12, 2023 at 12:07 AM Tariq Toukan <ttoukan.linux@gmail.com> wrote:
>>>>
>>>>
>>>>
>>>> On 12/01/2023 2:32, Stanislav Fomichev wrote:
>>>>> From: Toke Høiland-Jørgensen <toke@redhat.com>
>>>>>
>>>>> Preparation for implementing HW metadata kfuncs. No functional change.
>>>>>
>>>>> Cc: Tariq Toukan <tariqt@nvidia.com>
>>>>> Cc: Saeed Mahameed <saeedm@nvidia.com>
>>>>> Cc: John Fastabend <john.fastabend@gmail.com>
>>>>> Cc: David Ahern <dsahern@gmail.com>
>>>>> Cc: Martin KaFai Lau <martin.lau@linux.dev>
>>>>> Cc: Jakub Kicinski <kuba@kernel.org>
>>>>> Cc: Willem de Bruijn <willemb@google.com>
>>>>> Cc: Jesper Dangaard Brouer <brouer@redhat.com>
>>>>> Cc: Anatoly Burakov <anatoly.burakov@intel.com>
>>>>> Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
>>>>> Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
>>>>> Cc: Maryam Tahhan <mtahhan@redhat.com>
>>>>> Cc: xdp-hints@xdp-project.net
>>>>> Cc: netdev@vger.kernel.org
>>>>> Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
>>>>> Signed-off-by: Stanislav Fomichev <sdf@google.com>
>>>>> ---
>>>>> drivers/net/ethernet/mellanox/mlx5/core/en.h | 1 +
>>>>> .../net/ethernet/mellanox/mlx5/core/en/xdp.c | 3 +-
>>>>> .../net/ethernet/mellanox/mlx5/core/en/xdp.h | 6 +-
>>>>> .../ethernet/mellanox/mlx5/core/en/xsk/rx.c | 25 ++++----
>>>>> .../net/ethernet/mellanox/mlx5/core/en_rx.c | 58 +++++++++----------
>>>>> 5 files changed, 50 insertions(+), 43 deletions(-)
>>>>>
>>>>> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h b/drivers/net/ethernet/mellanox/mlx5/core/en.h
>>>>> index 2d77fb8a8a01..af663978d1b4 100644
>>>>> --- a/drivers/net/ethernet/mellanox/mlx5/core/en.h
>>>>> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h
>>>>> @@ -469,6 +469,7 @@ struct mlx5e_txqsq {
>>>>> union mlx5e_alloc_unit {
>>>>> struct page *page;
>>>>> struct xdp_buff *xsk;
>>>>> + struct mlx5e_xdp_buff *mxbuf;
>>>>
>>>> In XSK files below you mix usage of both alloc_units[page_idx].mxbuf and
>>>> alloc_units[page_idx].xsk, while both fields share the memory of a union.
>>>>
>>>> As struct mlx5e_xdp_buff wraps struct xdp_buff, I think that you just
>>>> need to change the existing xsk field type from struct xdp_buff *xsk
>>>> into struct mlx5e_xdp_buff *xsk and align the usage.
>>>
>>> Hmmm, good point. I'm actually not sure how it works currently.
>>> mlx5e_alloc_unit.mxbuf doesn't seem to be initialized anywhere? Toke,
>>> am I missing something?
>>
>> It's initialised piecemeal in different places; but yeah, we're mixing
>> things a bit...
>>
>>> I'm thinking about something like this:
>>>
>>> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h
>>> b/drivers/net/ethernet/mellanox/mlx5/core/en.h
>>> index af663978d1b4..2d77fb8a8a01 100644
>>> --- a/drivers/net/ethernet/mellanox/mlx5/core/en.h
>>> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h
>>> @@ -469,7 +469,6 @@ struct mlx5e_txqsq {
>>> union mlx5e_alloc_unit {
>>> struct page *page;
>>> struct xdp_buff *xsk;
>>> - struct mlx5e_xdp_buff *mxbuf;
>>> };
>>
>> Hmm, for consistency with the non-XSK path we should rather go the other
>> direction and lose the xsk member, moving everything to mxbuf? Let me
>> give that a shot...
>
> Something like the below?
>
> -Toke
>
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h b/drivers/net/ethernet/mellanox/mlx5/core/en.h
> index 6de02d8aeab8..cb9cdb6421c5 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en.h
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h
> @@ -468,7 +468,6 @@ struct mlx5e_txqsq {
>
> union mlx5e_alloc_unit {
> struct page *page;
> - struct xdp_buff *xsk;
> struct mlx5e_xdp_buff *mxbuf;
> };
>
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.h b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.h
> index cb568c62aba0..95694a25ec31 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.h
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.h
> @@ -33,6 +33,7 @@
> #define __MLX5_EN_XDP_H__
>
> #include <linux/indirect_call_wrapper.h>
> +#include <net/xdp_sock_drv.h>
>
> #include "en.h"
> #include "en/txrx.h"
> @@ -112,6 +113,21 @@ static inline void mlx5e_xmit_xdp_doorbell(struct mlx5e_xdpsq *sq)
> }
> }
>
> +static inline struct mlx5e_xdp_buff *mlx5e_xsk_buff_alloc(struct xsk_buff_pool *pool)
> +{
> + return (struct mlx5e_xdp_buff *)xsk_buff_alloc(pool);
What about the space needed for the rq / cqe fields? xsk_buff_alloc
won't allocate it.
> +}
> +
> +static inline void mlx5e_xsk_buff_free(struct mlx5e_xdp_buff *mxbuf)
> +{
> + xsk_buff_free(&mxbuf->xdp);
> +}
> +
> +static inline dma_addr_t mlx5e_xsk_buff_xdp_get_frame_dma(struct mlx5e_xdp_buff *mxbuf)
> +{
> + return xsk_buff_xdp_get_frame_dma(&mxbuf->xdp);
> +}
> +
> /* Enable inline WQEs to shift some load from a congested HCA (HW) to
> * a less congested cpu (SW).
> */
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c
> index 8bf3029abd3c..1f166dbb7f22 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c
> @@ -3,7 +3,6 @@
>
> #include "rx.h"
> #include "en/xdp.h"
> -#include <net/xdp_sock_drv.h>
> #include <linux/filter.h>
>
> /* RX data path */
> @@ -21,7 +20,7 @@ int mlx5e_xsk_alloc_rx_mpwqe(struct mlx5e_rq *rq, u16 ix)
> if (unlikely(!xsk_buff_can_alloc(rq->xsk_pool, rq->mpwqe.pages_per_wqe)))
> goto err;
>
> - BUILD_BUG_ON(sizeof(wi->alloc_units[0]) != sizeof(wi->alloc_units[0].xsk));
> + BUILD_BUG_ON(sizeof(wi->alloc_units[0]) != sizeof(wi->alloc_units[0].mxbuf));
> XSK_CHECK_PRIV_TYPE(struct mlx5e_xdp_buff);
> batch = xsk_buff_alloc_batch(rq->xsk_pool, (struct xdp_buff **)wi->alloc_units,
> rq->mpwqe.pages_per_wqe);
This batching API gets broken as well...
xsk_buff_alloc_batch fills an array of struct xdp_buff pointers, it
cannot correctly act on the array of struct mlx5e_xdp_buff, as it
contains additional fields.
Maybe letting mlx5e_xdp_buff point to its struct xdp_buff (instead of
wrapping it) will solve the problems here, then we'll loop over the
xdp_buff * array and copy the pointers into the struct mlx5e_xdp_buff *
array.
Need to give it deeper thoughts...
struct mlx5e_xdp_buff {
struct xdp_buff *xdp;
struct mlx5_cqe64 *cqe;
struct mlx5e_rq *rq;
};
> @@ -33,8 +32,8 @@ int mlx5e_xsk_alloc_rx_mpwqe(struct mlx5e_rq *rq, u16 ix)
> * the first error, which will mean there are no more valid descriptors.
> */
> for (; batch < rq->mpwqe.pages_per_wqe; batch++) {
> - wi->alloc_units[batch].xsk = xsk_buff_alloc(rq->xsk_pool);
> - if (unlikely(!wi->alloc_units[batch].xsk))
> + wi->alloc_units[batch].mxbuf = mlx5e_xsk_buff_alloc(rq->xsk_pool);
> + if (unlikely(!wi->alloc_units[batch].mxbuf))
> goto err_reuse_batch;
> }
>
> @@ -44,7 +43,7 @@ int mlx5e_xsk_alloc_rx_mpwqe(struct mlx5e_rq *rq, u16 ix)
>
> if (likely(rq->mpwqe.umr_mode == MLX5E_MPWRQ_UMR_MODE_ALIGNED)) {
> for (i = 0; i < batch; i++) {
> - dma_addr_t addr = xsk_buff_xdp_get_frame_dma(wi->alloc_units[i].xsk);
> + dma_addr_t addr = mlx5e_xsk_buff_xdp_get_frame_dma(wi->alloc_units[i].mxbuf);
>
> umr_wqe->inline_mtts[i] = (struct mlx5_mtt) {
> .ptag = cpu_to_be64(addr | MLX5_EN_WR),
> @@ -53,7 +52,7 @@ int mlx5e_xsk_alloc_rx_mpwqe(struct mlx5e_rq *rq, u16 ix)
> }
> } else if (unlikely(rq->mpwqe.umr_mode == MLX5E_MPWRQ_UMR_MODE_UNALIGNED)) {
> for (i = 0; i < batch; i++) {
> - dma_addr_t addr = xsk_buff_xdp_get_frame_dma(wi->alloc_units[i].xsk);
> + dma_addr_t addr = mlx5e_xsk_buff_xdp_get_frame_dma(wi->alloc_units[i].mxbuf);
>
> umr_wqe->inline_ksms[i] = (struct mlx5_ksm) {
> .key = rq->mkey_be,
> @@ -65,7 +64,7 @@ int mlx5e_xsk_alloc_rx_mpwqe(struct mlx5e_rq *rq, u16 ix)
> u32 mapping_size = 1 << (rq->mpwqe.page_shift - 2);
>
> for (i = 0; i < batch; i++) {
> - dma_addr_t addr = xsk_buff_xdp_get_frame_dma(wi->alloc_units[i].xsk);
> + dma_addr_t addr = mlx5e_xsk_buff_xdp_get_frame_dma(wi->alloc_units[i].mxbuf);
>
> umr_wqe->inline_ksms[i << 2] = (struct mlx5_ksm) {
> .key = rq->mkey_be,
> @@ -91,7 +90,7 @@ int mlx5e_xsk_alloc_rx_mpwqe(struct mlx5e_rq *rq, u16 ix)
> __be32 frame_size = cpu_to_be32(rq->xsk_pool->chunk_size);
>
> for (i = 0; i < batch; i++) {
> - dma_addr_t addr = xsk_buff_xdp_get_frame_dma(wi->alloc_units[i].xsk);
> + dma_addr_t addr = mlx5e_xsk_buff_xdp_get_frame_dma(wi->alloc_units[i].mxbuf);
>
> umr_wqe->inline_klms[i << 1] = (struct mlx5_klm) {
> .key = rq->mkey_be,
> @@ -137,7 +136,7 @@ int mlx5e_xsk_alloc_rx_mpwqe(struct mlx5e_rq *rq, u16 ix)
>
> err_reuse_batch:
> while (--batch >= 0)
> - xsk_buff_free(wi->alloc_units[batch].xsk);
> + mlx5e_xsk_buff_free(wi->alloc_units[batch].mxbuf);
>
> err:
> rq->stats->buff_alloc_err++;
> @@ -156,7 +155,7 @@ int mlx5e_xsk_alloc_rx_wqes_batched(struct mlx5e_rq *rq, u16 ix, int wqe_bulk)
> * allocate XDP buffers straight into alloc_units.
> */
> BUILD_BUG_ON(sizeof(rq->wqe.alloc_units[0]) !=
> - sizeof(rq->wqe.alloc_units[0].xsk));
> + sizeof(rq->wqe.alloc_units[0].mxbuf));
> buffs = (struct xdp_buff **)rq->wqe.alloc_units;
> contig = mlx5_wq_cyc_get_size(wq) - ix;
> if (wqe_bulk <= contig) {
> @@ -177,8 +176,9 @@ int mlx5e_xsk_alloc_rx_wqes_batched(struct mlx5e_rq *rq, u16 ix, int wqe_bulk)
> /* Assumes log_num_frags == 0. */
> frag = &rq->wqe.frags[j];
>
> - addr = xsk_buff_xdp_get_frame_dma(frag->au->xsk);
> + addr = mlx5e_xsk_buff_xdp_get_frame_dma(frag->au->mxbuf);
> wqe->data[0].addr = cpu_to_be64(addr + rq->buff.headroom);
> + frag->au->mxbuf->rq = rq;
> }
>
> return alloc;
> @@ -199,12 +199,13 @@ int mlx5e_xsk_alloc_rx_wqes(struct mlx5e_rq *rq, u16 ix, int wqe_bulk)
> /* Assumes log_num_frags == 0. */
> frag = &rq->wqe.frags[j];
>
> - frag->au->xsk = xsk_buff_alloc(rq->xsk_pool);
> - if (unlikely(!frag->au->xsk))
> + frag->au->mxbuf = mlx5e_xsk_buff_alloc(rq->xsk_pool);
> + if (unlikely(!frag->au->mxbuf))
> return i;
>
> - addr = xsk_buff_xdp_get_frame_dma(frag->au->xsk);
> + addr = mlx5e_xsk_buff_xdp_get_frame_dma(frag->au->mxbuf);
> wqe->data[0].addr = cpu_to_be64(addr + rq->buff.headroom);
> + frag->au->mxbuf->rq = rq;
> }
>
> return wqe_bulk;
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
> index 7b08653be000..4313165709cb 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
> @@ -41,7 +41,6 @@
> #include <net/gro.h>
> #include <net/udp.h>
> #include <net/tcp.h>
> -#include <net/xdp_sock_drv.h>
> #include "en.h"
> #include "en/txrx.h"
> #include "en_tc.h"
> @@ -434,7 +433,7 @@ static inline void mlx5e_free_rx_wqe(struct mlx5e_rq *rq,
> * put into the Reuse Ring, because there is no way to return
> * the page to the userspace when the interface goes down.
> */
> - xsk_buff_free(wi->au->xsk);
> + mlx5e_xsk_buff_free(wi->au->mxbuf);
> return;
> }
>
> @@ -515,7 +514,7 @@ mlx5e_free_rx_mpwqe(struct mlx5e_rq *rq, struct mlx5e_mpw_info *wi, bool recycle
> */
> for (i = 0; i < rq->mpwqe.pages_per_wqe; i++)
> if (no_xdp_xmit || !test_bit(i, wi->xdp_xmit_bitmap))
> - xsk_buff_free(alloc_units[i].xsk);
> + mlx5e_xsk_buff_free(alloc_units[i].mxbuf);
> } else {
> for (i = 0; i < rq->mpwqe.pages_per_wqe; i++)
> if (no_xdp_xmit || !test_bit(i, wi->xdp_xmit_bitmap))
>
next prev parent reply other threads:[~2023-01-13 20:53 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-01-12 0:32 [xdp-hints] [PATCH bpf-next v7 00/17] xdp: hints via kfuncs Stanislav Fomichev
2023-01-12 0:32 ` [xdp-hints] [PATCH bpf-next v7 01/17] bpf: Document XDP RX metadata Stanislav Fomichev
2023-01-16 13:09 ` [xdp-hints] " Jesper Dangaard Brouer
2023-01-17 20:33 ` Stanislav Fomichev
2023-01-18 14:28 ` Jesper Dangaard Brouer
2023-01-18 17:55 ` Stanislav Fomichev
2023-01-12 0:32 ` [xdp-hints] [PATCH bpf-next v7 02/17] bpf: Rename bpf_{prog,map}_is_dev_bound to is_offloaded Stanislav Fomichev
2023-01-12 0:32 ` [xdp-hints] [PATCH bpf-next v7 03/17] bpf: Move offload initialization into late_initcall Stanislav Fomichev
2023-01-12 0:32 ` [xdp-hints] [PATCH bpf-next v7 04/17] bpf: Reshuffle some parts of bpf/offload.c Stanislav Fomichev
2023-01-12 0:32 ` [xdp-hints] [PATCH bpf-next v7 05/17] bpf: Introduce device-bound XDP programs Stanislav Fomichev
2023-01-12 0:32 ` [xdp-hints] [PATCH bpf-next v7 06/17] selftests/bpf: Update expected test_offload.py messages Stanislav Fomichev
2023-01-12 0:32 ` [xdp-hints] [PATCH bpf-next v7 07/17] bpf: XDP metadata RX kfuncs Stanislav Fomichev
2023-01-12 0:32 ` [xdp-hints] [PATCH bpf-next v7 09/17] veth: Introduce veth_xdp_buff wrapper for xdp_buff Stanislav Fomichev
2023-01-12 0:32 ` [xdp-hints] [PATCH bpf-next v7 10/17] veth: Support RX XDP metadata Stanislav Fomichev
2023-01-16 16:21 ` [xdp-hints] " Jesper Dangaard Brouer
2023-01-17 20:33 ` Stanislav Fomichev
2023-01-18 15:57 ` Jesper Dangaard Brouer
2023-01-12 0:32 ` [xdp-hints] [PATCH bpf-next v7 11/17] selftests/bpf: Verify xdp_metadata xdp->af_xdp path Stanislav Fomichev
2023-01-12 0:32 ` [xdp-hints] [PATCH bpf-next v7 12/17] net/mlx4_en: Introduce wrapper for xdp_buff Stanislav Fomichev
2023-01-12 0:32 ` [xdp-hints] [PATCH bpf-next v7 13/17] net/mlx4_en: Support RX XDP metadata Stanislav Fomichev
2023-01-12 0:32 ` [xdp-hints] [PATCH bpf-next v7 14/17] xsk: Add cb area to struct xdp_buff_xsk Stanislav Fomichev
2023-01-12 0:32 ` [xdp-hints] [PATCH bpf-next v7 15/17] net/mlx5e: Introduce wrapper for xdp_buff Stanislav Fomichev
2023-01-12 8:07 ` [xdp-hints] " Tariq Toukan
2023-01-12 19:10 ` Stanislav Fomichev
2023-01-12 21:09 ` Toke Høiland-Jørgensen
2023-01-12 21:55 ` Toke Høiland-Jørgensen
2023-01-12 22:18 ` Stanislav Fomichev
2023-01-12 22:29 ` Toke Høiland-Jørgensen
2023-01-13 20:55 ` Tariq Toukan
2023-01-13 20:53 ` Tariq Toukan [this message]
2023-01-13 21:31 ` Toke Høiland-Jørgensen
2023-01-15 6:59 ` Tariq Toukan
2023-01-15 11:13 ` Toke Høiland-Jørgensen
2023-01-12 0:32 ` [xdp-hints] [PATCH bpf-next v7 16/17] net/mlx5e: Support RX XDP metadata Stanislav Fomichev
2023-01-12 8:13 ` [xdp-hints] " Tariq Toukan
2023-01-12 19:09 ` Stanislav Fomichev
2023-01-13 20:25 ` Tariq Toukan
2023-01-12 0:32 ` [xdp-hints] [PATCH bpf-next v7 17/17] selftests/bpf: Simple program to dump XDP RX metadata Stanislav Fomichev
2023-01-12 7:29 ` [xdp-hints] Re: [PATCH bpf-next v7 00/17] xdp: hints via kfuncs Martin KaFai Lau
2023-01-12 8:19 ` Tariq Toukan
2023-01-12 18:09 ` Stanislav Fomichev
2023-01-12 18:20 ` Martin KaFai Lau
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