On Thu, 20 Jun 2019 at 19:25, Kevin Laatz <kevin.laatz@xxxxxxxxx> wrote:
>
> This patch modifies xdpsock to use mmap instead of posix_memalign. With
> this change, we can use hugepages when running the application in unaligned
> chunks mode. Using hugepages makes it more likely that we have physically
> contiguous memory, which supports the unaligned chunk mode better.
>
> Signed-off-by: Kevin Laatz <kevin.laatz@xxxxxxxxx>
Acked-by: Björn Töpel <bjorn.topel@xxxxxxxxx>
> ---
> samples/bpf/xdpsock_user.c | 14 +++++++++-----
> 1 file changed, 9 insertions(+), 5 deletions(-)
>
> diff --git a/samples/bpf/xdpsock_user.c b/samples/bpf/xdpsock_user.c
> index 7b4ce047deb2..8ed63ad68428 100644
> --- a/samples/bpf/xdpsock_user.c
> +++ b/samples/bpf/xdpsock_user.c
> @@ -74,6 +74,7 @@ static int opt_interval = 1;
> static u64 opt_buffer_size = XSK_UMEM__DEFAULT_FRAME_SIZE;
> static u32 opt_umem_flags;
> static int opt_unaligned_chunks;
> +static int opt_mmap_flags;
> static u32 opt_xdp_bind_flags;
> static __u32 prog_id;
>
> @@ -438,6 +439,7 @@ static void parse_command_line(int argc, char **argv)
> case 'u':
> opt_umem_flags |= XDP_UMEM_UNALIGNED_CHUNKS;
> opt_unaligned_chunks = 1;
> + opt_mmap_flags = MAP_HUGETLB;
> break;
> case 'b':
> opt_buffer_size = atoi(optarg);
> @@ -707,11 +709,13 @@ int main(int argc, char **argv)
> exit(EXIT_FAILURE);
> }
>
> - ret = posix_memalign(&bufs, getpagesize(), /* PAGE_SIZE aligned */
> - NUM_FRAMES * opt_buffer_size);
> - if (ret)
> - exit_with_error(ret);
> -
> + /* Reserve memory for the umem. Use hugepages if unaligned chunk mode */
> + bufs = mmap(NULL, NUM_FRAMES * opt_buffer_size, PROT_READ|PROT_WRITE,
> + MAP_PRIVATE|MAP_ANONYMOUS|opt_mmap_flags, -1, 0);
> + if (bufs == MAP_FAILED) {
> + printf("ERROR: mmap failed\n");
> + exit(EXIT_FAILURE);
> + }
> /* Create sockets... */
> umem = xsk_configure_umem(bufs,
> NUM_FRAMES * opt_buffer_size);
> --
> 2.17.1
>
