[tip:perf/urgent] perf tools: Unwind properly location after REJECT

[tip-bot for Jiri Olsa]

Commit-ID:  9445464bb8318e42e5232b37fc7218ed028517f6
Gitweb:     https://git.kernel.org/tip/9445464bb8318e42e5232b37fc7218ed028517f6
Author:     Jiri Olsa <jolsa@xxxxxxxxxx>
AuthorDate: Thu, 12 Oct 2017 17:03:38 +0200
Committer:  Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Fri, 27 Oct 2017 11:42:51 -0300

perf tools: Unwind properly location after REJECT

We have defined YY_USER_ACTION to keep trace of the column location
during events parsing, but we need to clean it up when we call REJECT.

When REJECT is called, the lexer shrinks the text and re-runs the
matching, so we need to address it in resuming the previous location
value to keep it correct for error display, like:

Before:
  $ perf stat -e 'cpu/uops_executed.core,krava/'  true
  event syntax error: '..38;5;9:mi=01;05;37;41:su=48;5;196;38;5;15:sg=48;5;1\
1;38;5;16:ca=48;5;196;38;5;226:tw=48;5;10;38;5;16:ow=48;5;10;38;5;21:st=48;5;\
21;38;50
ï'
                                  \___ unknown term

After:
  $ ./perf stat -e 'cpu/uops_executed.core,krava/'  true
  event syntax error: '..cuted.core,krava/'
                                    \___ unknown term

Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Reported-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Tested-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Tested-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: Changbin Du <changbin.du@xxxxxxxxx>
Cc: David Ahern <dsahern@xxxxxxxxx>
Cc: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Wang Nan <wangnan0@xxxxxxxxxx>
Link: http://lkml.kernel.org/n/tip-vug2hchlny30jfsfrumbym26@xxxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/20171009140944.GD28623@xxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
 tools/perf/util/parse-events.l | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l
index dcfdafd..6680e4f 100644
--- a/tools/perf/util/parse-events.l
+++ b/tools/perf/util/parse-events.l
@@ -154,6 +154,10 @@ do {							\
 	yycolumn += yyleng;				\
 } while (0);
 
+#define USER_REJECT		\
+	yycolumn -= yyleng;	\
+	REJECT
+
 %}
 
 %x mem
@@ -335,8 +339,8 @@ r{num_raw_hex}		{ return raw(yyscanner); }
 {num_hex}		{ return value(yyscanner, 16); }
 
 {modifier_event}	{ return str(yyscanner, PE_MODIFIER_EVENT); }
-{bpf_object}		{ if (!isbpf(yyscanner)) REJECT; return str(yyscanner, PE_BPF_OBJECT); }
-{bpf_source}		{ if (!isbpf(yyscanner)) REJECT; return str(yyscanner, PE_BPF_SOURCE); }
+{bpf_object}		{ if (!isbpf(yyscanner)) USER_REJECT; return str(yyscanner, PE_BPF_OBJECT); }
+{bpf_source}		{ if (!isbpf(yyscanner)) USER_REJECT; return str(yyscanner, PE_BPF_SOURCE); }
 {name}			{ return pmu_str_check(yyscanner); }
 "/"			{ BEGIN(config); return '/'; }
 -			{ return '-'; }