On Fri, Feb 14, 2025 at 2:40 PM Martin KaFai Lau <martin.lau@xxxxxxxxx> wrote: > > On 2/13/25 10:12 PM, Jason Xing wrote: > > On Fri, Feb 14, 2025 at 1:41 PM Martin KaFai Lau <martin.lau@xxxxxxxxx> wrote: > >> > >> On 2/13/25 7:09 PM, Jason Xing wrote: > >>> On Fri, Feb 14, 2025 at 10:14 AM Martin KaFai Lau <martin.lau@xxxxxxxxx> wrote: > >>>> > >>>> On 2/13/25 3:57 PM, Jason Xing wrote: > >>>>> On Fri, Feb 14, 2025 at 7:41 AM Stanislav Fomichev<stfomichev@xxxxxxxxx> wrote: > >>>>>> On 02/13, Jason Xing wrote: > >>>>>>> Support bpf_setsockopt() to set the maximum value of RTO for > >>>>>>> BPF program. > >>>>>>> > >>>>>>> Signed-off-by: Jason Xing<kerneljasonxing@xxxxxxxxx> > >>>>>>> --- > >>>>>>> Documentation/networking/ip-sysctl.rst | 3 ++- > >>>>>>> include/uapi/linux/bpf.h | 2 ++ > >>>>>>> net/core/filter.c | 6 ++++++ > >>>>>>> tools/include/uapi/linux/bpf.h | 2 ++ > >>>>>>> 4 files changed, 12 insertions(+), 1 deletion(-) > >>>>>>> > >>>>>>> diff --git a/Documentation/networking/ip-sysctl.rst b/Documentation/networking/ip-sysctl.rst > >>>>>>> index 054561f8dcae..78eb0959438a 100644 > >>>>>>> --- a/Documentation/networking/ip-sysctl.rst > >>>>>>> +++ b/Documentation/networking/ip-sysctl.rst > >>>>>>> @@ -1241,7 +1241,8 @@ tcp_rto_min_us - INTEGER > >>>>>>> > >>>>>>> tcp_rto_max_ms - INTEGER > >>>>>>> Maximal TCP retransmission timeout (in ms). > >>>>>>> - Note that TCP_RTO_MAX_MS socket option has higher precedence. > >>>>>>> + Note that TCP_BPF_RTO_MAX and TCP_RTO_MAX_MS socket option have the > >>>>>>> + higher precedence for configuring this setting. > >>>>>> The cover letter needs more explanation about the motivation. > >>>> > >>>> +1 > >>>> > >>>> I haven't looked at the patches. The cover letter has no word on the use case. > >> > >> The question was your _use case_ in bpf. Not what the TCP_RTO_MAX_MS does. Your > >> current use case is to have bpf setting it after reading the tcp header option, > >> like the selftest in patch 3? > > > > Oops, I misunderstood the real situation of the tcp header option > > test. My intention is to bpf_setsockopt() just like setget_sockopt > > does. > > > > Thanks for reminding me. I will totally remove the header test in the > > next version. > > If your use case was in the header, it is ok although it won't be the first I was planning to add a simple test to only see if the rto max for bpf feature works, so I found the rto min selftests and then did a similar one. > useful place I have in my mind. Regardless, it is useful to say a few words > where you are planning to set it in the bpf. During a cb in sockops or during > socket create ...etc. Without it, we can only guess from the selftest :( I see your point. After evaluating and comparing those two tests, I think the setsock_opt is a better place to go. Do we even apply the use of rto min to setsock_opt as well? What do you think? > > > > >> > >>> > >>> I will add and copy some words from Eric's patch series :) > >> > >> > >>>>> I am targeting the net-next tree because of recent changes[1] made by > >>>>> Eric. It probably hasn't merged into the bpf-next tree. > >>>> > >>>> There is the bpf-next/net tree. It should have the needed changes. > >>> > >>> [1] was recently merged in the net-next tree, so the only one branch I > >>> can target is net-next. > >>> > >>> [1]: https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git/commit/?id=ae9b3c0e79bc > >>> > >>> Am I missing something? > >> > >> There is a net branch: > ^^^ > > >> https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git > > > > But this branch hasn't included the rto max feature. I was trying to > > Which branch? I was talking about the **net** branch. Not the master branch. Try > to pull again if your local copy does not have it. The net branch should have > the TCP_RTO_MAX_MS patches. Oh, I always use the master branch, never heard of net branch. You're right, I checked out the net branch and then found it. Thanks. One more thing I have to ask in advance is that in this case what the title looks like? [patch bpf] or [patch bpf net]? Thanks, Jason > > > say that what I wrote is based on the rto max feature which only > > exists in the net-next tree for now. > > > >
