Re: [RFC PATCH v5 03/30] tools build: Add feature check for eBPF API

From: Wangnan (F)
Date: Tue Jun 02 2015 - 21:16:47 EST




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:
... dwarf: [ OFF ]
... glibc: [ on ]
... gtk2: [ on ]
... libaudit: [ OFF ]
... libbfd: [ on ]
... libelf: [ OFF ]
... libnuma: [ OFF ]
... libperl: [ on ]
... libpython: [ OFF ]
... libslang: [ OFF ]
... libunwind: [ OFF ]
... libdw-dwarf-unwind: [ OFF ]
... zlib: [ OFF ]
... lzma: [ OFF ]
... bpf: [ OFF ]

config/Makefile:245: No libelf found, disables 'probe' tool, please install elfutils-libelf-devel/libelf-dev
config/Makefile:325: Disabling post unwind, no support found.
config/Makefile:366: No libaudit.h found, disables 'trace' tool, please install audit-libs-devel or libaudit-dev
config/Makefile:381: slang not found, disables TUI support. Please install slang-devel or libslang-dev
config/Makefile:466: No 'Python.h' (for Python 2.x support) was found: disables Python support - please install python-devel/python-dev
config/Makefile:556: No liblzma found, disables xz kernel module decompression, please install xz-devel/liblzma-dev
config/Makefile:569: No numa.h found, disables 'perf bench numa mem' benchmark, please install numactl-devel/libnuma-devel/libnuma-dev
MKDIR /tmp/build/perf/util/
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.


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?

Thank you.


- Arnaldo


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