netdev - Re: [PATCH bpf-next v8 1/3] bpf: remove extra lock_sock for TCP_ZEROCOPY

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 14 Jan 2021 19:27:32 -0800
From:   Alexei Starovoitov <alexei.starovoitov@...il.com>
To:     Stanislav Fomichev <sdf@...gle.com>
Cc:     Network Development <netdev@...r.kernel.org>,
        bpf <bpf@...r.kernel.org>, Alexei Starovoitov <ast@...nel.org>,
        Daniel Borkmann <daniel@...earbox.net>,
        Martin KaFai Lau <kafai@...com>,
        Song Liu <songliubraving@...com>,
        Eric Dumazet <edumazet@...gle.com>
Subject: Re: [PATCH bpf-next v8 1/3] bpf: remove extra lock_sock for TCP_ZEROCOPY_RECEIVE

On Wed, Jan 13, 2021 at 1:33 PM Stanislav Fomichev <sdf@...gle.com> wrote:
>
> Add custom implementation of getsockopt hook for TCP_ZEROCOPY_RECEIVE.
> We skip generic hooks for TCP_ZEROCOPY_RECEIVE and have a custom
> call in do_tcp_getsockopt using the on-stack data. This removes
> 3% overhead for locking/unlocking the socket.
>
> Without this patch:
>      3.38%     0.07%  tcp_mmap  [kernel.kallsyms]  [k] __cgroup_bpf_run_filter_getsockopt
>             |
>              --3.30%--__cgroup_bpf_run_filter_getsockopt
>                        |
>                         --0.81%--__kmalloc
>
> With the patch applied:
>      0.52%     0.12%  tcp_mmap  [kernel.kallsyms]  [k] __cgroup_bpf_run_filter_getsockopt_kern
>
> Signed-off-by: Stanislav Fomichev <sdf@...gle.com>
> Cc: Martin KaFai Lau <kafai@...com>
> Cc: Song Liu <songliubraving@...com>
> Cc: Eric Dumazet <edumazet@...gle.com>
> Acked-by: Martin KaFai Lau <kafai@...com>

Few issues in this patch and the patch 2 doesn't apply:
Switched to a new branch 'tmp'
Applying: bpf: Remove extra lock_sock for TCP_ZEROCOPY_RECEIVE
.git/rebase-apply/patch:295: trailing whitespace.
#endif
.git/rebase-apply/patch:306: trailing whitespace.
union tcp_word_hdr {
.git/rebase-apply/patch:309: trailing whitespace.
};
.git/rebase-apply/patch:311: trailing whitespace.
#define tcp_flag_word(tp) ( ((union tcp_word_hdr *)(tp))->words [3])
.git/rebase-apply/patch:313: trailing whitespace.
enum {
warning: squelched 1 whitespace error
warning: 6 lines add whitespace errors.
Applying: bpf: Try to avoid kzalloc in cgroup/{s,g}etsockopt
error: patch failed: kernel/bpf/cgroup.c:1390
error: kernel/bpf/cgroup.c: patch does not apply
Patch failed at 0002 bpf: Try to avoid kzalloc in cgroup/{s,g}etsockopt