On Wed, Apr 28, 2021 at 02:42:31PM +0300, Gal Pressman wrote:
> The new attribute indicates that the kernel copies DMA pages on fork,
> hence fork support through madvise and MADV_DONTFORK is not needed.
>
> If the attribute is not reported (expected on older kernels),
> copy-on-fork is disabled.
>
> Example:
> $ rdma sys
> netns shared
> copy-on-fork on
I don't think that we need to print them on separate lines.
$ rdma sys
netns shared copy-on-fork on
>
> Signed-off-by: Gal Pressman <galpress@xxxxxxxxxx>
> ---
> rdma/sys.c | 9 +++++++++
> 1 file changed, 9 insertions(+)
>
> diff --git a/rdma/sys.c b/rdma/sys.c
> index 8fb565d70598..dd9c6da33e2a 100644
> --- a/rdma/sys.c
> +++ b/rdma/sys.c
> @@ -38,6 +38,15 @@ static int sys_show_parse_cb(const struct nlmsghdr *nlh, void *data)
> print_color_string(PRINT_ANY, COLOR_NONE, "netns", "netns %s\n",
> mode_str);
> }
> +
> + if (tb[RDMA_NLDEV_SYS_ATTR_COPY_ON_FORK])
> + print_color_on_off(PRINT_ANY, COLOR_NONE, "copy-on-fork",
> + "copy-on-fork %s\n",
> + mnl_attr_get_u8(tb[RDMA_NLDEV_SYS_ATTR_COPY_ON_FORK]));
> + else
> + print_color_on_off(PRINT_ANY, COLOR_NONE, "copy-on-fork",
> + "copy-on-fork %s\n", false);
Let's simplify it
bool cow = false;
+ if (tb[RDMA_NLDEV_SYS_ATTR_COPY_ON_FORK])
+ cow = mnl_attr_get_u8(tb[RDMA_NLDEV_SYS_ATTR_COPY_ON_FORK]);
+
+ print_color_on_off(PRINT_ANY, COLOR_NONE, "copy-on-fork", "copy-on-fork %s", cow);
> +
> return MNL_CB_OK;
> }
>
> --
> 2.31.1
>
