linux/tools/perf
Wang Nan 7a0119468c perf bpf: Mute libbpf when '-v' not set
According to [1], libbpf should be muted. This patch reset info and
warning message level to ensure libbpf doesn't output anything even
if error happened.

[1] http://lkml.kernel.org/r/20151020151255.GF5119@kernel.org

Committer note:

Before:

Testing it with an incompatible kernel version in the .c file that
generated foo.o:

  [root@zoo ~]# perf record -e /tmp/foo.o sleep 1
  libbpf: load bpf program failed: Invalid argument
  libbpf: -- BEGIN DUMP LOG ---
  libbpf:

  libbpf: -- END LOG --
  libbpf: failed to load program 'fork=_do_fork'
  libbpf: failed to load object '/tmp/foo.o'
  event syntax error: '/tmp/foo.o'
                       \___ Invalid argument: Are you root and runing a CONFIG_BPF_SYSCALL kernel?

  (add -v to see detail)
  Run 'perf list' for a list of valid events

   Usage: perf record [<options>] [<command>]
      or: perf record [<options>] -- <command> [<options>]

      -e, --event <event>   event selector. use 'perf list' to list available events
  [root@zoo ~]#

After:

  [root@zoo ~]# perf record -e /tmp/foo.o sleep 1
  event syntax error: '/tmp/foo.o'
                       \___ Invalid argument: Are you root and runing a CONFIG_BPF_SYSCALL kernel?

  (add -v to see detail)
  Run 'perf list' for a list of valid events

   Usage: perf record [<options>] [<command>]
      or: perf record [<options>] -- <command> [<options>]

      -e, --event <event>   event selector. use 'perf list' to list available events
  [root@zoo ~]#

This, BTW, need fixing to emit a proper message by validating the
version in the foo.o "version" ELF section against the running kernel,
warning the user instead of asking the kernel to load a binary that it
will refuse due to unmatching kernel version.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1446547486-229499-3-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-03 12:06:04 -03:00
..
arch perf tests: Add Intel CQM test 2015-10-05 16:56:07 -03:00
bench perf bench: Use named initializers in the trailer too 2015-10-19 18:17:25 -03:00
config perf tools: Make perf depend on libbpf 2015-10-28 12:48:12 -03:00
Documentation perf record: Add clang options for compiling BPF scripts 2015-10-29 17:16:22 -03:00
python perf python: Support the PERF_RECORD_SWITCH event 2015-10-07 19:41:50 -03:00
scripts perf tools: Add more documentation to export-to-postgresql.py script 2015-09-28 16:53:07 -03:00
tests perf test: Keep test result clean if '-v' not set 2015-11-03 11:45:40 -03:00
trace/strace/groups perf trace: Add read/write to the file group 2015-09-04 13:22:06 -03:00
ui perf annotate: Don't die() when finding an invalid config option 2015-10-22 18:10:52 -03:00
util perf bpf: Mute libbpf when '-v' not set 2015-11-03 12:06:04 -03:00
.gitignore perf tools: Add Intel PT instruction decoder 2015-08-17 11:11:36 -03:00
Build perf trace: Support 'strace' syscall event groups 2015-07-20 15:16:32 -03:00
builtin-annotate.c perf env: Rename some leftovers from rename to perf_env 2015-09-14 12:50:20 -03:00
builtin-bench.c perf bench: Run benchmarks, don't test them 2015-10-19 16:10:25 -03:00
builtin-buildid-cache.c perf buildid: Introduce sysfs/filename__sprintf_build_id 2015-08-28 14:53:50 -03:00
builtin-buildid-list.c perf buildid: Introduce sysfs/filename__sprintf_build_id 2015-08-28 14:53:50 -03:00
builtin-data.c perf data: Support using -f to override perf.data file ownership for 'convert' 2015-04-02 13:18:52 -03:00
builtin-diff.c perf callchain: Allow disabling call graphs per event 2015-08-12 13:20:28 -03:00
builtin-evlist.c perf tools: Introduce usage_with_options_msg() 2015-10-27 09:28:44 -03:00
builtin-help.c perf help: Change 'usage' to 'Usage' for consistency 2015-10-19 16:51:44 -03:00
builtin-inject.c perf inject: Add --strip option to strip out non-synthesized events 2015-09-28 17:19:51 -03:00
builtin-kmem.c perf machine: Add method for common kernel_map(FUNCTION) operation 2015-09-30 18:34:29 -03:00
builtin-kvm.c tools lib api fs: Replace debugfs/tracefs objects interface with fs.c 2015-09-14 12:50:15 -03:00
builtin-list.c perf list: Do event name substring search as last resort when no events found 2015-10-01 12:12:22 -03:00
builtin-lock.c perf machine: Protect the machine->threads with a rwlock 2015-05-08 16:19:27 -03:00
builtin-mem.c perf mem: Fill in the missing session freeing after an error occurs 2015-07-01 17:53:49 -03:00
builtin-probe.c perf tools: Introduce usage_with_options_msg() 2015-10-27 09:28:44 -03:00
builtin-record.c perf record: Add clang options for compiling BPF scripts 2015-10-29 17:16:22 -03:00
builtin-report.c perf report: Rename to --show-cpu-utilization 2015-10-26 14:06:04 -03:00
builtin-sched.c perf tools: Introduce usage_with_options_msg() 2015-10-27 09:28:44 -03:00
builtin-script.c perf script: Enable printing of branch stack 2015-10-29 17:16:20 -03:00
builtin-stat.c perf stat: Cache aggregated map entries in extra cpumap 2015-10-27 15:08:07 -03:00
builtin-timechart.c perf tools: Elliminate alignment holes 2015-05-18 10:17:33 -03:00
builtin-top.c perf tools: Improve call graph documents and help messages 2015-10-22 16:23:19 -03:00
builtin-trace.c perf trace: Add cmd string table to decode sys_bpf first arg 2015-10-29 11:48:18 -03:00
builtin.h perf tools: Add new 'perf data' command 2015-02-25 12:42:25 -03:00
command-list.txt perf tools: Add new 'perf data' command 2015-02-25 12:42:25 -03:00
CREDITS
design.txt
Makefile perf build: Fix single target build dependency check 2015-06-22 11:27:09 -03:00
Makefile.perf perf tools: Make sure fixdep is built before libbpf 2015-10-29 17:16:21 -03:00
MANIFEST perf tools: Make perf depend on libbpf 2015-10-28 12:48:12 -03:00
perf-archive.sh
perf-completion.sh perf tools: Avoid confusion with preloaded bash function for perf bash completion 2015-03-19 13:53:27 -03:00
perf-read-vdso.c perf tools: Build programs to copy 32-bit compatibility 2014-10-29 10:32:48 -02:00
perf-sys.h perf tools: Move generic barriers out of perf-sys.h 2015-05-08 16:05:08 -03:00
perf-with-kcore.sh perf tools: Fix perf-with-kcore handling of arguments containing spaces 2015-08-06 16:48:27 -03:00
perf.c perf tools: Enable passing bpf object file to --event 2015-10-28 12:48:12 -03:00
perf.h perf record: Add ability to name registers to record 2015-08-31 18:01:33 -03:00