Re: [PATCH v5 24/29] icmp: use iov_tail rather than pool

[Stefano Brivio <sbrivio@redhat.com>]

On Thu, 17 Apr 2025 18:51:31 +0200
Laurent Vivier <lvivier@redhat.com> wrote:

> As the iov_tail has a non zero offset (because of the presence of
> packet headers in the iov array), we must copy it to a new
> iov array (using iov_splice()) to pass it to sendmsg().
> 
> We cannot use anymore iov_tail_msghdr(), so remove it.
> 
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> ---
>  icmp.c | 30 +++++++++++++++++++-----------
>  icmp.h |  2 +-
>  iov.c  | 23 -----------------------
>  iov.h  |  2 --
>  tap.c  |  7 ++-----
>  5 files changed, 22 insertions(+), 42 deletions(-)
> 
> diff --git a/icmp.c b/icmp.c
> index d27d860b4af4..44d431d53c96 100644
> --- a/icmp.c
> +++ b/icmp.c
> @@ -44,6 +44,7 @@
>  
>  #define ICMP_ECHO_TIMEOUT	60 /* s, timeout for ICMP socket activity */
>  #define ICMP_NUM_IDS		(1U << 16)
> +#define MAX_IOV_ICMP		16

Is there any specific / normative reason why you picked 16 here, or
it's arbitrary and supposed to be good enough? If it's arbitrary,
perhaps indicate it with /* Arbitrary, should be enough */ or suchlike.

-- 
Stefano