[PATCH] perf, tools: Handle events including .c and .o

[Wang Nan <wangnan0@huawei.com>]

This patch helps with Sukadev's JSON event tree where such events can happen.

>From Andi Kleen:
 Any event inclduing a .c/.o/.bpf currently triggers BPF compilation or loading
 and then an error. This can happen for some Intel JSON events, which cannot
 be used.

This patch fixes this problem by forbidding BPF file patch containing '{', '}'
and ',', make sure flex consumes the leading '{', instead of matcing it using
a BPF file path.

Tested result:

  $ perf stat -e '{unc_p_clockticks,unc_p_power_state_occupancy.cores_c0}' -a -I 1000
  invalid or unsupported event: '{unc_p_clockticks,unc_p_power_state_occupancy.cores_c0}'
  Run 'perf list' for a list of valid events
  (as expected, interperted as event)

  $ perf stat -e 'aaa.c' -a -I 1000
  ERROR: problems with path aaa.c: No such file or directory
  (as expected, interperted as BPF source)

  $ perf stat -e 'aaa.ccc' -a -I 1000
  invalid or unsupported event: 'aaa.ccc'
  (as expected, interperted as event)

  $ perf stat -e '{aaa.c}' -a -I 1000
  ERROR: problems with path aaa.c: No such file or directory
  event syntax error: '{aaa.c}'
  <SKIP>
  (as expected, interperted as BPF source)

  $ perf stat -e '{cycles,aaa.c}' -a -I 1000
  ERROR: problems with path aaa.c: No such file or directory
  event syntax error: '{cycles,aaa.c}'
  (as expected, interperted as BPF source)

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
---
 tools/perf/util/parse-events.l | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l
index 9f43fda..660fca0 100644
--- a/tools/perf/util/parse-events.l
+++ b/tools/perf/util/parse-events.l
@@ -136,8 +136,8 @@ do {							\
 group		[^,{}/]*[{][^}]*[}][^,{}/]*
 event_pmu	[^,{}/]+[/][^/]*[/][^,{}/]*
 event		[^,{}/]+
-bpf_object	.*\.(o|bpf)
-bpf_source	.*\.c
+bpf_object	[^,{}]+\.(o|bpf)
+bpf_source	[^,{}]+\.c
 
 num_dec		[0-9]+
 num_hex		0x[a-fA-F0-9]+
-- 
1.8.3.4