On Fri, Apr 09, 2021 at 03:30:18PM +0200, Olivier Matz wrote: > On Thu, Apr 08, 2021 at 09:58:35AM -0300, Flavio Leitner wrote: > > On Thu, Apr 08, 2021 at 02:05:21PM +0200, Olivier Matz wrote: > > > On Thu, Apr 08, 2021 at 08:21:58AM -0300, Flavio Leitner wrote: > > > > On Thu, Apr 08, 2021 at 09:41:59AM +0200, Olivier Matz wrote: > > > > > On Wed, Apr 07, 2021 at 05:15:39PM -0300, Flavio Leitner wrote: > > > > > > On Thu, Apr 01, 2021 at 11:52:40AM +0200, David Marchand wrote: > > > > > > > Tx offload flags are of the application responsibility. > > > > > > > Leave the mbuf alone and check for TSO where needed. > > > > > > > > > > > > > > Signed-off-by: David Marchand <david.march...@redhat.com> > > > > > > > --- > > > > > > > > > > > > The patch looks good, but maybe a better approach would be > > > > > > to change the documentation to require the TCP_CKSUM flag > > > > > > when TCP_SEG is used, otherwise this flag adjusting needs > > > > > > to be replicated every time TCP_SEG is used. > > > > > > > > > > > > The above could break existing applications, so perhaps doing > > > > > > something like below would be better and backwards compatible? > > > > > > Then we can remove those places tweaking the flags completely. > > > > > > > > > > As a first step, I suggest to document that: > > > > > - applications must set TCP_CKSUM when setting TCP_SEG > > > > > > > > That's what I suggest above. > > > > > > > > > - pmds must suppose that TCP_CKSUM is set when TCP_SEG is set > > > > > > > > But that keeps the problem of implying the TCP_CKSUM flag in > > > > various places. > > > > > > Yes. What I propose is just a first step: better document what is the > > > current expected behavior, before doing something else. > > > > > > > > This is clearer that what we have today, and I think it does not break > > > > > anything. This will guide apps in the correct direction, facilitating > > > > > an eventual future PMD change. [...] > > I see your point. Going back to improving the documentation as a > > first step, what would be the next steps? Are we going to wait few > > releases and then remove the flag tweaking code assuming that PMDs > > and apps are ok? > > After this documentation step, in few releases, we could relax the > constraint on PMD: applications will be expected to set TCP_CKSUM when > TCP_SEG is set, so no need for the PMD to force TCP_CKSUM to 1 if > TCP_SEG is set. The documentation will be updated again. > > This plan can be described in the deprecation notice, and later in the > release note. > > How does it sound?
Works for me. Thanks, -- fbl
