[PATCH] Ensure that umask is set if the extra bits (edge, inv, cmask) are used

When testing ocount on some of the Intel processor it was discovered
that that the umask not not being set for events that specified the
the extra bits.  Below is an example of the problem on an Intel Ivy
Bridge processor with the event code missing the 0x03 unit masks for
the events:

$  ocount --verbose -e int_misc:recovery_cycles -e int_misc:recovery_stalls_count ls
Final event code is 140000d
Final event code is 144000d
Number of events passed is 2
Exec args are: ls
telling child to start app
parent says start app /usr/bin/ls
calling perf_event_open for pid 240d
perf_event_open returning fd 9
perf_event_open returning fd a
perf counter setup complete
app 240d is running
going into waitpid on monitored app 240d
app process ended normally.
Reading counter data for event int_misc
Reading counter data for event int_misc

Events were actively counted for 1070382 nanoseconds.
Event counts (actual) for /usr/bin/ls:
	Event                                 Count                    % time counted
	int_misc:recovery_cycles              0                        100.00
	int_misc:recovery_stalls_count        0                        100.00

With this patch the umasks are included and the example executes correctly:

$  ocount --verbose -e int_misc:recovery_cycles -e int_misc:recovery_stalls_count ls
Final event code is 140030d
Final event code is 144030d
Number of events passed is 2
Exec args are: ls
telling child to start app
calling perf_event_open for pid 72e1
parent says start app /usr/bin/ls
perf_event_open returning fd 9
perf_event_open returning fd a
perf counter setup complete
app 72e1 is running
going into waitpid on monitored app 72e1
app process ended normally.
Reading counter data for event int_misc
Reading counter data for event int_misc

Events were actively counted for 1216948 nanoseconds.
Event counts (actual) for /usr/bin/ls:
	Event                                 Count                    % time counted
	int_misc:recovery_cycles              69,730                   100.00
	int_misc:recovery_stalls_count        14,800                   100.00

Signed-off-by: William Cohen <[email protected]>
---
 libop/op_events.c | 3 +++
 libop/op_events.h | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/libop/op_events.c b/libop/op_events.c
index 99266c6..2badc8e 100644
--- a/libop/op_events.c
+++ b/libop/op_events.c
@@ -238,6 +238,9 @@ static void parse_um_entry(struct op_described_um * entry, char const * line)
 	if (strisprefix(c, "extra:")) {
 		c += 6;
 		entry->extra = parse_extra(c);
+		/* include the regular umask if there are real extra bits */
+		if (entry->extra != EXTRA_NONE)
+			entry->extra |= (entry->value & UMASK_MASK) << UMASK_SHIFT;
 		/* named mask */
 		c = skip_nonws(c);
 		c = skip_ws(c);
diff --git a/libop/op_events.h b/libop/op_events.h
index ec345e5..f09c830 100644
--- a/libop/op_events.h
+++ b/libop/op_events.h
@@ -20,6 +20,9 @@ extern "C" {
 #include "op_types.h"
 #include "op_list.h"
 
+#define UMASK_SHIFT 8
+#define UMASK_MASK 0xff
+
 #define EXTRA_EDGE (1U << 18)
 #define EXTRA_MIN_VAL EXTRA_EDGE
 
-- 
2.1.0


------------------------------------------------------------------------------
Dive into the World of Parallel Programming The Go Parallel Website, sponsored
by Intel and developed in partnership with Slashdot Media, is your hub for all
things parallel software development, from weekly thought leadership blogs to
news, videos, case studies, tutorials and more. Take a look and join the 
conversation now. http://goparallel.sourceforge.net/