Re: [PATCH net-next 2/6] mptcp: implement wmem reservation

[Mat Martineau <mathew.j.martineau@linux.intel.com>]

On Fri, 27 Nov 2020, Paolo Abeni wrote:

> This leverages the previous commit to reserve the wmem
> required for the sendmsg() operation when the msk socket
> lock is first acquired.
> Some heuristics are used to get a reasonable [over] estimation of
> the whole memory required. If we can't forward alloc such amount
> fallback to a reasonable small chunk, otherwise enter the wait
> for memory path.
>
> When sendmsg() needs more memory it looks at wmem_reserved
> first and if that is exhausted, move more space from
> sk_forward_alloc.
>
> The reserved memory is not persistent and is released at the
> next socket unlock via the release_cb().
>
> Overall this will simplify the next patch.
>
> Acked-by: Florian Westphal <fw@strlen.de>
> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
> ---
> net/mptcp/protocol.c | 92 ++++++++++++++++++++++++++++++++++++++++----
> net/mptcp/protocol.h |  1 +
> 2 files changed, 86 insertions(+), 7 deletions(-)

Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>

--
Mat Martineau
Intel