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3 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Arnaldo Carvalho de Melo
|
65f041bee7 |
tools lib bpf: Use FEATURE_USER to allow building in the same dir as perf
When building tools/lib/bpf as part of the tools/perf/ build process,
which will happend when we introduce a patch wiring that up, we end up
stomping on the feature detection caching mechanism, that uses a file in
the output directory (O=) that is shared by libbpf and perf to check if
something changed from one build to another that requires redoing the
feature detection process.
By using the recently introduced FEATURE_USER tools/build/ knob, we can
avoid that:
Before, every make invokation would run the feature detection:
$ make O=/tmp/build/perf -C tools/perf
make: Entering directory '/home/git/linux/tools/perf'
Auto-detecting system features:
... dwarf: [ on ]
... glibc: [ on ]
<SNIP>
... get_cpuid: [ on ]
... bpf: [ on ]
GEN perf-archive
GEN perf-with-kcore
Auto-detecting system features:
... libelf: [ on ]
... bpf: [ on ]
<SNIP>
After:
$ make O=/tmp/build/perf -C tools/perf
make: Entering directory '/home/git/linux/tools/perf'
BUILD: Doing 'make -j4' parallel build
make: Leaving directory '/home/git/linux/tools/perf'
$
Because we now have two different feature detection state files:
$ ls -la /tmp/build/perf/FEATURE-DUMP*
-rw-rw-r--. 1 acme acme 338 Sep 21 17:25 /tmp/build/perf/FEATURE-DUMP
-rw-rw-r--. 1 acme acme 33 Sep 21 17:25 /tmp/build/perf/FEATURE-DUMP.libbpf
$
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: pi3orama@163.com
Fixes:
|
||
|
Arnaldo Carvalho de Melo
|
20517cd9c5 |
tools lib bpf: Fix up FEATURE_{TESTS,DISPLAY} usage
When libbpf was introduced it wrongly asked for the "libelf" and "bpf"
feature tests to be performed (via FEATURE_TESTS), while asking that
"libbpf", "libelf-mmap", "libelf-getphdrnum" and "bpf" to have the
result of its respective tests to be displayed (via FEATURE_DISPLAY).
Due to another recently bug fixed in the tools/build/ infrastructure
("tools build: Fixup feature detection display function name") the
results for the entries in the FEATURE_DISPLAY, for this case, were
appearing as all succeeding, when two of them (the ones only on the
DISPLAY) were not even being performed.
Before:
$ make -C tools/lib/bpf/
make: Entering directory '/home/git/linux/tools/lib/bpf'
Auto-detecting system features:
... libelf: [ on ]
... libelf-getphdrnum: [ OFF ]
... libelf-mmap: [ OFF ]
... bpf: [ on ]
<SNIP>
After, with FEATURE_TESTS == FEATURE_DISPLAY:
Auto-detecting system features:
... libelf: [ on ]
... libelf-getphdrnum: [ on ]
... libelf-mmap: [ on ]
... bpf: [ on ]
<SNIP>
I just inverted, so that it tests the four features but displays just
the libelf and mmap ones, to make it more compact. So it becomes:
$ make -C tools/lib/bpf/
make: Entering directory '/home/git/linux/tools/lib/bpf'
Auto-detecting system features:
... libelf: [ on ]
... bpf: [ on ]
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: pi3orama@163.com
Fixes:
|
||
Wang Nan
|
1b76c13e4b |
bpf tools: Introduce 'bpf' library and add bpf feature check
This is the first patch of libbpf. The goal of libbpf is to create a standard way for accessing eBPF object files. This patch creates 'Makefile' and 'Build' for it, allows 'make' to build libbpf.a and libbpf.so, 'make install' to put them into proper directories. Most part of Makefile is borrowed from traceevent. Before building, it checks the existence of libelf in Makefile, and deny to build if not found. Instead of throwing an error if libelf not found, the error raises in a phony target "elfdep". This design is to ensure 'make clean' still workable even if libelf is not found. Because libbpf requires 'kern_version' field set for 'union bpf_attr' (bpfdep" is used for that dependency), Kernel BPF API is also checked by intruducing a new feature check 'bpf' into tools/build/feature, which checks the existence and version of linux/bpf.h. When building libbpf, it searches that file from include/uapi/linux in kernel source tree (controlled by FEATURE_CHECK_CFLAGS-bpf). Since it searches kernel source tree it reside, installing of newest kernel headers is not required, except we are trying to port these files to an old kernel. To avoid checking that file when perf building, the newly introduced 'bpf' feature check doesn't added into FEATURE_TESTS and FEATURE_DISPLAY by default in tools/build/Makefile.feature, but added into libbpf's specific. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Bcc: pi3orama@163.com Link: http://lkml.kernel.org/r/1435716878-189507-4-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |