selftests/powerpc: Purge extra count_pmc() calls of ebb selftests
authorDesnes A. Nunes do Rosario <desnesn@linux.ibm.com>
Fri, 26 Jun 2020 16:47:37 +0000 (13:47 -0300)
committerMichael Ellerman <mpe@ellerman.id.au>
Wed, 8 Jul 2020 12:09:31 +0000 (22:09 +1000)
An extra count on ebb_state.stats.pmc_count[PMC_INDEX(pmc)] is being per-
formed when count_pmc() is used to reset PMCs on a few selftests. This
extra pmc_count can occasionally invalidate results, such as the ones from
cycles_test shown hereafter. The ebb_check_count() failed with an above
the upper limit error due to the extra value on ebb_state.stats.pmc_count.

Furthermore, this extra count is also indicated by extra PMC1 trace_log on
the output of the cycle test (as well as on pmc56_overflow_test):

==========
   ...
   [21]: counter = 8
   [22]: register SPRN_MMCR0 = 0x0000000080000080
   [23]: register SPRN_PMC1  = 0x0000000080000004
   [24]: counter = 9
   [25]: register SPRN_MMCR0 = 0x0000000080000080
   [26]: register SPRN_PMC1  = 0x0000000080000004
   [27]: counter = 10
   [28]: register SPRN_MMCR0 = 0x0000000080000080
   [29]: register SPRN_PMC1  = 0x0000000080000004
>> [30]: register SPRN_PMC1  = 0x000000004000051e
PMC1 count (0x280000546) above upper limit 0x2800003e8 (+0x15e)
[FAIL] Test FAILED on line 52
failure: cycles
==========

Signed-off-by: Desnes A. Nunes do Rosario <desnesn@linux.ibm.com>
Tested-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200626164737.21943-1-desnesn@linux.ibm.com
tools/testing/selftests/powerpc/pmu/ebb/back_to_back_ebbs_test.c
tools/testing/selftests/powerpc/pmu/ebb/cycles_test.c
tools/testing/selftests/powerpc/pmu/ebb/cycles_with_freeze_test.c
tools/testing/selftests/powerpc/pmu/ebb/cycles_with_mmcr2_test.c
tools/testing/selftests/powerpc/pmu/ebb/ebb.c
tools/testing/selftests/powerpc/pmu/ebb/ebb_on_willing_child_test.c
tools/testing/selftests/powerpc/pmu/ebb/lost_exception_test.c
tools/testing/selftests/powerpc/pmu/ebb/multi_counter_test.c
tools/testing/selftests/powerpc/pmu/ebb/multi_ebb_procs_test.c
tools/testing/selftests/powerpc/pmu/ebb/pmae_handling_test.c
tools/testing/selftests/powerpc/pmu/ebb/pmc56_overflow_test.c

index a2d7b0e..a26ac12 100644 (file)
@@ -91,8 +91,6 @@ int back_to_back_ebbs(void)
        ebb_global_disable();
        ebb_freeze_pmcs();
 
-       count_pmc(1, sample_period);
-
        dump_ebb_state();
 
        event_close(&event);
index bc89381..bb9f587 100644 (file)
@@ -42,8 +42,6 @@ int cycles(void)
        ebb_global_disable();
        ebb_freeze_pmcs();
 
-       count_pmc(1, sample_period);
-
        dump_ebb_state();
 
        event_close(&event);
index dcd351d..9ae795c 100644 (file)
@@ -99,8 +99,6 @@ int cycles_with_freeze(void)
        ebb_global_disable();
        ebb_freeze_pmcs();
 
-       count_pmc(1, sample_period);
-
        dump_ebb_state();
 
        printf("EBBs while frozen %d\n", ebbs_while_frozen);
index 94c99c1..4b45a2e 100644 (file)
@@ -71,8 +71,6 @@ int cycles_with_mmcr2(void)
        ebb_global_disable();
        ebb_freeze_pmcs();
 
-       count_pmc(1, sample_period);
-
        dump_ebb_state();
 
        event_close(&event);
index dfbc5c3..21537d6 100644 (file)
@@ -396,8 +396,6 @@ int ebb_child(union pipe read_pipe, union pipe write_pipe)
        ebb_global_disable();
        ebb_freeze_pmcs();
 
-       count_pmc(1, sample_period);
-
        dump_ebb_state();
 
        event_close(&event);
index ca2f7d7..b208bf6 100644 (file)
@@ -38,8 +38,6 @@ static int victim_child(union pipe read_pipe, union pipe write_pipe)
        ebb_global_disable();
        ebb_freeze_pmcs();
 
-       count_pmc(1, sample_period);
-
        dump_ebb_state();
 
        FAIL_IF(ebb_state.stats.ebb_count == 0);
index ac3e6e1..ba2681a 100644 (file)
@@ -75,7 +75,6 @@ static int test_body(void)
        ebb_freeze_pmcs();
        ebb_global_disable();
 
-       count_pmc(4, sample_period);
        mtspr(SPRN_PMC4, 0xdead);
 
        dump_summary_ebb_state();
index b8242e9..791d37b 100644 (file)
@@ -70,13 +70,6 @@ int multi_counter(void)
        ebb_global_disable();
        ebb_freeze_pmcs();
 
-       count_pmc(1, sample_period);
-       count_pmc(2, sample_period);
-       count_pmc(3, sample_period);
-       count_pmc(4, sample_period);
-       count_pmc(5, sample_period);
-       count_pmc(6, sample_period);
-
        dump_ebb_state();
 
        for (i = 0; i < 6; i++)
index a05c0e1..9b0f70d 100644 (file)
@@ -61,8 +61,6 @@ static int cycles_child(void)
        ebb_global_disable();
        ebb_freeze_pmcs();
 
-       count_pmc(1, sample_period);
-
        dump_summary_ebb_state();
 
        event_close(&event);
index 153ebc9..2904c74 100644 (file)
@@ -82,8 +82,6 @@ static int test_body(void)
        ebb_global_disable();
        ebb_freeze_pmcs();
 
-       count_pmc(1, sample_period);
-
        dump_ebb_state();
 
        if (mmcr0_mismatch)
index eadad75..b29f8ba 100644 (file)
@@ -76,8 +76,6 @@ int pmc56_overflow(void)
        ebb_global_disable();
        ebb_freeze_pmcs();
 
-       count_pmc(2, sample_period);
-
        dump_ebb_state();
 
        printf("PMC5/6 overflow %d\n", pmc56_overflowed);