Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752307AbdHPN3R (ORCPT ); Wed, 16 Aug 2017 09:29:17 -0400 Received: from www62.your-server.de ([213.133.104.62]:44503 "EHLO www62.your-server.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752253AbdHPN3P (ORCPT ); Wed, 16 Aug 2017 09:29:15 -0400 Message-ID: <5994489E.1020806@iogearbox.net> Date: Wed, 16 Aug 2017 15:29:02 +0200 From: Daniel Borkmann User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: Michael Ellerman , ast@kernel.org CC: davem@davemloft.net, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] bpf: Update sysctl documentation to list all supported architectures References: <1502860557-20247-1-git-send-email-mpe@ellerman.id.au> <5993FFC9.8010206@iogearbox.net> <8760dnu5sf.fsf@concordia.ellerman.id.au> In-Reply-To: <8760dnu5sf.fsf@concordia.ellerman.id.au> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-Authenticated-Sender: daniel@iogearbox.net Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1911 Lines: 44 On 08/16/2017 01:10 PM, Michael Ellerman wrote: > Daniel Borkmann writes: >> On 08/16/2017 07:15 AM, Michael Ellerman wrote: >>> The sysctl documentation states that the JIT is only available on >>> x86_64, which is no longer correct. >>> >>> Update the list to include all architectures that enable HAVE_CBPF_JIT >>> or HAVE_EBPF_JIT under some configuration. >>> >>> Signed-off-by: Michael Ellerman >> >> Thanks for the patch! >> >>> Documentation/sysctl/net.txt | 5 +++-- >>> 1 file changed, 3 insertions(+), 2 deletions(-) >>> >>> diff --git a/Documentation/sysctl/net.txt b/Documentation/sysctl/net.txt >>> index 14db18c970b1..f68356024d09 100644 >>> --- a/Documentation/sysctl/net.txt >>> +++ b/Documentation/sysctl/net.txt >>> @@ -36,8 +36,9 @@ bpf_jit_enable >>> -------------- >>> >>> This enables Berkeley Packet Filter Just in Time compiler. >>> -Currently supported on x86_64 architecture, bpf_jit provides a framework >>> -to speed packet filtering, the one used by tcpdump/libpcap for example. >>> +Currently supported on arm, arm64, mips, powerpc, s390, sparc and x86_64 >>> +architectures, bpf_jit provides a framework to speed packet filtering, the one >>> +used by tcpdump/libpcap for example. >> >> Good point, could we actually make that as a bullet list and >> differentiate between cBPF and eBPF JITs, so that a user doesn't >> need to run git grep HAVE_{E,C}BPF_JIT to figure it out what the >> switch enables on the arch used? That would be great. > > We could. > > Does a user of the sysctl want/need to know the difference though? Or do > they just want to turn on "the JIT"? They would just turn it on, but I think it would be nice to inform them which archs support eBPF (which is a superset of cBPF in term of what can be jited), so in case they have some native eBPF programs they would see whether these can also be jited.