selftests/powerpc: Count more instructions & use decimal
authorMichael Ellerman <mpe@ellerman.id.au>
Wed, 23 Jul 2014 07:31:36 +0000 (17:31 +1000)
committerBenjamin Herrenschmidt <benh@kernel.crashing.org>
Mon, 28 Jul 2014 04:11:31 +0000 (14:11 +1000)
Although we expect some small discrepancies for very large counts, we
seem to be able to count up to 64 billion instructions without too much
skew, so do so.

Also switch to using decimals for the instruction counts. This just
makes it easier to visually compare the expected vs actual values, as
well as the raw result from instructions.

Before:

  instructions: result 68719476753 running/enabled 13101961654
  cycles: result 38077343785 running/enabled 13101725752
  Looped for 68719476736 instructions, overhead 17
  Expected 68719476753
  Actual   68719476753
  Delta    0, 0.000000%
  success: count_instructions

After:
  instructions: result 64000000016 running/enabled 12197599964
  cycles: result 35412471674 running/enabled 12197534110
  Looped for 64000000000 instructions, overhead 16
  Expected 64000000016
  Actual   64000000016
  Delta    0, 0.000000%
  success: count_instructions

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
tools/testing/selftests/powerpc/pmu/count_instructions.c

index 5e241e14f2040109c510275e80ccb7c36c898f9a..4622117b24c0b94a0cc09c7512f4eae13a9b71f3 100644 (file)
@@ -112,17 +112,23 @@ static int test_body(void)
        overhead = determine_overhead(events);
        printf("Overhead of null loop: %llu instructions\n", overhead);
 
-       /* Run for 1M instructions */
-       FAIL_IF(do_count_loop(events, 0x100000, overhead, true));
+       /* Run for 1Mi instructions */
+       FAIL_IF(do_count_loop(events, 1000000, overhead, true));
+
+       /* Run for 10Mi instructions */
+       FAIL_IF(do_count_loop(events, 10000000, overhead, true));
+
+       /* Run for 100Mi instructions */
+       FAIL_IF(do_count_loop(events, 100000000, overhead, true));
 
-       /* Run for 10M instructions */
-       FAIL_IF(do_count_loop(events, 0xa00000, overhead, true));
+       /* Run for 1Bi instructions */
+       FAIL_IF(do_count_loop(events, 1000000000, overhead, true));
 
-       /* Run for 100M instructions */
-       FAIL_IF(do_count_loop(events, 0x6400000, overhead, true));
+       /* Run for 16Bi instructions */
+       FAIL_IF(do_count_loop(events, 16000000000, overhead, true));
 
-       /* Run for 1G instructions */
-       FAIL_IF(do_count_loop(events, 0x40000000, overhead, true));
+       /* Run for 64Bi instructions */
+       FAIL_IF(do_count_loop(events, 64000000000, overhead, true));
 
        event_close(&events[0]);
        event_close(&events[1]);