Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <6fbd8c35-04de-c379-5062-a0b9d4a8ebbe@linux.dev>
Date:   Wed, 23 Nov 2022 16:40:50 -0800
MIME-Version: 1.0
Subject: Re: [PATCH bpf v2] bpf: Update bpf_{g,s}etsockopt() documentation
Content-Language: en-US
To:     Daniel Borkmann <daniel@iogearbox.net>,
        Ji Rongfeng <SikoJobs@outlook.com>
Cc:     ast@kernel.org, andrii@kernel.org, song@kernel.org, yhs@fb.com,
        john.fastabend@gmail.com, kpsingh@kernel.org, sdf@google.com,
        haoluo@google.com, jolsa@kernel.org, joannelkoong@gmail.com,
        kuifeng@fb.com, lorenzo@kernel.org, maximmi@nvidia.com,
        quentin@isovalent.com, bpf@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <DU0P192MB15479B86200B1216EC90E162D6099@DU0P192MB1547.EURP192.PROD.OUTLOOK.COM>
 <0977584d-8aff-624d-4cf8-a6e4868958c5@iogearbox.net>
From:   Martin KaFai Lau <martin.lau@linux.dev>
In-Reply-To: <0977584d-8aff-624d-4cf8-a6e4868958c5@iogearbox.net>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 8bit
Precedence: bulk

On 11/23/22 4:18 PM, Daniel Borkmann wrote:
> On 11/18/22 9:18 AM, Ji Rongfeng wrote:
>> * append missing optnames to the end
>> * simplify bpf_getsockopt()'s doc
>>
>> Signed-off-by: Ji Rongfeng <SikoJobs@outlook.com>
>> ---
>>   include/uapi/linux/bpf.h       | 20 ++++++++++++--------
>>   tools/include/uapi/linux/bpf.h | 20 ++++++++++++--------
>>   2 files changed, 24 insertions(+), 16 deletions(-)
>>
>> diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
>> index 51b9aa640ad2..14f29d95ea71 100644
>> --- a/include/uapi/linux/bpf.h
>> +++ b/include/uapi/linux/bpf.h
>> @@ -2576,14 +2576,19 @@ union bpf_attr {
>>    *         * **SOL_SOCKET**, which supports the following *optname*\ s:
>>    *           **SO_RCVBUF**, **SO_SNDBUF**, **SO_MAX_PACING_RATE**,
>>    *           **SO_PRIORITY**, **SO_RCVLOWAT**, **SO_MARK**,
>> - *           **SO_BINDTODEVICE**, **SO_KEEPALIVE**.
>> + *           **SO_BINDTODEVICE**, **SO_KEEPALIVE**, **SO_REUSEADDR**,
>> + *           **SO_REUSEPORT**, **SO_BINDTOIFINDEX**, **SO_TXREHASH**.
>>    *         * **IPPROTO_TCP**, which supports the following *optname*\ s:
>>    *           **TCP_CONGESTION**, **TCP_BPF_IW**,
>>    *           **TCP_BPF_SNDCWND_CLAMP**, **TCP_SAVE_SYN**,
>>    *           **TCP_KEEPIDLE**, **TCP_KEEPINTVL**, **TCP_KEEPCNT**,
>> - *          **TCP_SYNCNT**, **TCP_USER_TIMEOUT**, **TCP_NOTSENT_LOWAT**.
>> + *           **TCP_SYNCNT**, **TCP_USER_TIMEOUT**, **TCP_NOTSENT_LOWAT**,
>> + *           **TCP_NODELAY**, **TCP_MAXSEG**, **TCP_WINDOW_CLAMP**,
>> + *           **TCP_THIN_LINEAR_TIMEOUTS**, **TCP_BPF_DELACK_MAX**,
>> + *           **TCP_BPF_RTO_MIN**.
>>    *         * **IPPROTO_IP**, which supports *optname* **IP_TOS**.
>> - *         * **IPPROTO_IPV6**, which supports *optname* **IPV6_TCLASS**.
>> + *         * **IPPROTO_IPV6**, which supports the following *optname*\ s:
>> + *           **IPV6_TCLASS**, **IPV6_AUTOFLOWLABEL**.
>>    *     Return
>>    *         0 on success, or a negative error in case of failure.
>>    *
>> @@ -2800,12 +2805,11 @@ union bpf_attr {
>>    *           and **BPF_CGROUP_INET6_CONNECT**.
>>    *
>>    *         This helper actually implements a subset of **getsockopt()**.
>> - *         It supports the following *level*\ s:
>> + *         It supports the same set of *optname*\ s that supported by
> 
> nit: that is supported by
> 
>> + *         **bpf_setsockopt**\ () helper with a few exceptions:
>>    *
>> - *         * **IPPROTO_TCP**, which supports *optname*
>> - *           **TCP_CONGESTION**.
>> - *         * **IPPROTO_IP**, which supports *optname* **IP_TOS**.
>> - *         * **IPPROTO_IPV6**, which supports *optname* **IPV6_TCLASS**.
>> + *         * **bpf_setsockopt**\ () helper only: **TCP_BPF_***.
>> + *         * **bpf_getsockopt**\ () helper only: **TCP_SAVED_SYNC**.
> 
> I think from a user PoV the above is a bit hard to follow, maybe take Martin's
> earlier feedback into account and add a proper sentence; it will be much easier
> to understand.

+1  Made the change and also fixed TCP_SAVED_SYNC with s/SYNC/SYN/ while 
applying.  Thanks!