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Date: Wed, 3 Jun 2015 10:47:44 -0300
From: Arnaldo Carvalho de Melo <acme@kernel.org>
To: "Wangnan (F)" <wangnan0@huawei.com>
Cc: namhyung@kernel.org, alexei.starovoitov@gmail.com,
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Subject: Re: [RFC PATCH v5 03/30] tools build: Add feature check for eBPF API
Message-ID: <20150603134744.GW624@kernel.org>
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Em Wed, Jun 03, 2015 at 09:15:48AM +0800, Wangnan (F) escreveu:
> On 2015/6/3 6:11, Arnaldo Carvalho de Melo wrote:
> >Em Mon, Jun 01, 2015 at 07:37:49AM +0000, Wang Nan escreveu:
> >>In this patch, eBPF API is checked by compiling a c source file which
> >>uses fields in bpf_attr which will be used by libbpf.
> >Something is missing, where is the message saying that I need to install
> >something to have bpf support? Look at the liblzma one at config/Makefile:556:

> >[acme@zoo linux]$ rm -rf /tmp/build/perf ; mkdir -p /tmp/build/perf ; m
> >make: Entering directory '/home/git/linux/tools/perf'
> >   BUILD:   Doing 'make -j4' parallel build

> >Auto-detecting system features:

<SNIP>

> >...                          lzma: [ OFF ]
> >...                           bpf: [ OFF ]

> >config/Makefile:556: No liblzma found, disables xz kernel module decompression, please install xz-devel/liblzma-dev
> >   CC       /tmp/build/perf/util/abspath.o

> Those messages are printed by perf's makefile. I'll add them in patch
> 23/30 'perf tools: Make perf depend on libbpf'. I think error message
> in this patch is not required, because other feature checks are also
> silent when it found something is missing.

Ok, was just a distraction caused by this 'bpf: [ OFF ]' message, i.e.
probably the best was to not show anything, as the above only says
"yeah, the needed bigs for BPF support were not found, even tho we will
not use it now".

Anyway, will not let this hold processing the series, applying.
 
> >Applied the first two patches in this series, will push them soon.
> 
> Do you want me to repost a full v6 series with those error messages added or
> only repost a v6 of 23/30
> by replying the v5 patch?

No need.

- Arnaldo