perf tools: Reinstate 'signed' field flag for tracepoints
For some reason the libtraceevent tracepoint-parsing code is missing
the FIELD_IS_SIGNED flag-setting code, which causes problems for the
Perl trace event binding at least, since it ends up unable to
recognize negative numbers.
Things like checking for negative return values therefore fail, causing
scripts like rwtop to instead interpret the negative return value as a
large positive value, which in turn get added to e.g. read totals with
insanely invalid results.
So set the FIELD_IS_SIGNED flag for tracepoint events that specify
"signed:1".
Before:
# perf script record rw-by-pid
# perf script report rw-by-pid
read counts by pid:
pid comm # reads bytes_requested bytes_read
------ -------------------- ----------- ---------- ----------
753 Xorg 88 512000 7.74763251095801e+20
1619 firefox 42 462 2.58254417031934e+20
1232 gnome-shell 11 176 1.10680464442257e+20
1471 gnome-terminal 3 16366 18446744073709551615
1408 libsocialweb-co 2 32 18446744073709551613
After:
# perf script report rw-by-pid
read counts by pid:
pid comm # reads bytes_requested bytes_read
------ -------------------- ----------- ---------- ----------
753 Xorg 88 512000 2764
1619 firefox 42 462 126
1232 gnome-shell 11 176 40
1471 gnome-terminal 3 16366 10
1408 libsocialweb-co 2 32 8
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Link: http://lkml.kernel.org/r/1471b5968821a455cf5168bb4567964e74ecf530.1358527965.git.tom.zanussi@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c
index f504619..bb8b3db 100644
--- a/tools/lib/traceevent/event-parse.c
+++ b/tools/lib/traceevent/event-parse.c
@@ -1462,7 +1462,8 @@
if (read_expect_type(EVENT_ITEM, &token))
goto fail;
- /* add signed type */
+ if (strtoul(token, NULL, 0))
+ field->flags |= FIELD_IS_SIGNED;
free_token(token);
if (read_expected(EVENT_OP, ";") < 0)