Re: [RFC PATCH 0/3] net: ethernet: ti: cpsw: Add XDP support

From: BjÃrn TÃpel
Date: Thu Apr 18 2019 - 02:12:22 EST


On Wed, 17 Apr 2019 at 19:51, Ivan Khoronzhuk
<ivan.khoronzhuk@xxxxxxxxxx> wrote:
>
> This patchset is RFC adding XDP support for TI cpsw driver that is
> based on page_pool allocator. It was verified with af_xdp sockets
> and on xdp drop. For XDP redirect to another interface it's under
> verification, still not sure about all cases that should be verified.
> Also regular tests with iperf2 were done in order to verify impact on
> regular netstack performance, compared with base commit from
> net-next/master: 432bc230700f86801cffa5e159e05dea6229f722
>
> It was verified with following configs enabled:
> CONFIG_JIT=y
> CONFIG_BPFILTER=y
> CONFIG_BPF_SYSCALL=y
> CONFIG_XDP_SOCKETS=y
> CONFIG_BPF_EVENTS=y
> CONFIG_HAVE_EBPF_JIT=y
> CONFIG_BPF_JIT=y
> CONFIG_CGROUP_BPF=y
>
> iperf2 UDP RX summary (packet size / Mbps):
> +--------------------------------------------------------------+
> | pkt_size/rate | 1024 | 1500 | 1470 | 64 | 128 | 512 | 256 |
> |---------------+------+------+------+------+------+-----+-----|
> | base commit | 561 | 470 | 796 | 35 | 70.1 | 281 | 140 |
> |---------------+------+------+------+------+------+-----+-----|
> | XDP patched | 563 | 455 | 808 | 35 | 70.2 | 282 | 141 |
> +--------------------------------------------------------------+
>
> iperf2 UDP TX summary (packet size / Mbps):
> +--------------------------------------------------------------+
> | pkt_size/rate | 1024 | 1500 | 1470 | 64 | 128 | 512 | 256 |
> |---------------+------+------+------+------+------+-----+-----|
> | base commit | 555 | 666 | 736 | 34.5 | 70.3 | 281 | 140 |
> |---------------+------+------+------+------+------+-----+-----|
> | XDP patched | 558 | 696 | 759 | 35.2 | 69.2 | 279 | 140 |
> +--------------------------------------------------------------+
>
> iperf2 TCP summary (window size / Mbps):
> +------------------------------------------------------------+
> | window size/rate | 16 | 32 | 64 | 128 | 8 | 256 |
> |------------------+------+------+------+------+------+------|
> | base commit | 753 | 887 | 931 | 932 | 676 | 932 |
> |------------------+------+------+------+------+------+------|
> | XDP patched | 823 | 888 | 932 | 933 | 669 | 933 |
> +------------------------------------------------------------+
>
> For af_xdp socket type verification several generic changes should be added
> that can be seen here (rough fixes, for samples related seems like last version
> of samples is more integrated with libbpf api, so should be rebased,
> witch I will send as RFC separately):
> https://github.com/ikhorn/af_xdp_stuff/tree/af_xdp_armv7
>

More XDP support, yay!

As for mmap/AF_XDP on 32-bit systems; Instead of hacking the if_xdp.h,
mmap2 should be used. Have a look at the libbpf code here [1]


BjÃrn

[1] https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git/tree/tools/lib/bpf/xsk.c#n81


> Ivan Khoronzhuk (3):
> net: ethernet: ti: davinci_cpdma: add dma mapped submit
> net: ethernet: ti: davinci_cpdma: return handler status
> net: ethernet: ti: cpsw: add XDP support
>
> drivers/net/ethernet/ti/Kconfig | 1 +
> drivers/net/ethernet/ti/cpsw.c | 552 +++++++++++++++++++++---
> drivers/net/ethernet/ti/davinci_cpdma.c | 117 +++--
> drivers/net/ethernet/ti/davinci_cpdma.h | 6 +-
> drivers/net/ethernet/ti/davinci_emac.c | 18 +-
> 5 files changed, 591 insertions(+), 103 deletions(-)
>
> --
> 2.17.1
>