tcp: Replace min_tso_segs() with tso_segs() CC callback

This patch replaces the existing min_tso_segs() callback with a new
tso_segs() callback, allowing congestion control algorithms to provide
an explicit TSO segment count for each data burst and bypass
tcp_tso_autosize(). The resulting tso_segs value is clamped to
[1, sk->sk_gso_max_segs], preventing congestion-control implementations
from returning an invalid zero-segment value.

This change has the following impacts on BPF struct_ops users:
- The callback is renamed from min_tso_segs() to tso_segs()
- The signature gains an extra u32 mss_now argument
- The return value semantics is changed from "floor value passed into
  tcp_tso_autosize()" to "final tso_segs value", bypassing autosizing

As a result, existing BPF programs must be updated, because returning a
small constant will now directly limit the final tso_segs value instead
of specifying the minimum value passed to tcp_tso_autosize().

Signed-off-by: Chia-Yu Chang <chia-yu.chang@nokia-bell-labs.com>
Signed-off-by: Ilpo Järvinen <ij@kernel.org>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

0 files changed, 0 insertions, 0 deletions