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selftests/powerpc: Add cycles test with MMCR2 handling
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
authored by
Michael Ellerman
and committed by
Benjamin Herrenschmidt
985ac68e
c418a678
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tools/testing/selftests/powerpc/pmu/ebb/Makefile
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tools/testing/selftests/powerpc/pmu/ebb/Makefile
···
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close_clears_pmcc_test instruction_count_test \
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fork_cleanup_test ebb_on_child_test \
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ebb_on_willing_child_test back_to_back_ebbs_test \
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lost_exception_test no_handler_test
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lost_exception_test no_handler_test \
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cycles_with_mmcr2_test
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all: $(PROGS)
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tools/testing/selftests/powerpc/pmu/ebb/cycles_with_mmcr2_test.c
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tools/testing/selftests/powerpc/pmu/ebb/cycles_with_mmcr2_test.c
···
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/*
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* Copyright 2014, Michael Ellerman, IBM Corp.
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* Licensed under GPLv2.
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <stdbool.h>
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#include "ebb.h"
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/*
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* Test of counting cycles while manipulating the user accessible bits in MMCR2.
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*/
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/* We use two values because the first freezes PMC1 and so we would get no EBBs */
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#define MMCR2_EXPECTED_1 0x4020100804020000UL /* (FC1P|FC2P|FC3P|FC4P|FC5P|FC6P) */
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#define MMCR2_EXPECTED_2 0x0020100804020000UL /* ( FC2P|FC3P|FC4P|FC5P|FC6P) */
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int cycles_with_mmcr2(void)
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{
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struct event event;
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uint64_t val, expected[2], actual;
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int i;
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bool bad_mmcr2;
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event_init_named(&event, 0x1001e, "cycles");
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event_leader_ebb_init(&event);
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event.attr.exclude_kernel = 1;
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event.attr.exclude_hv = 1;
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event.attr.exclude_idle = 1;
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FAIL_IF(event_open(&event));
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ebb_enable_pmc_counting(1);
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setup_ebb_handler(standard_ebb_callee);
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ebb_global_enable();
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FAIL_IF(ebb_event_enable(&event));
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mtspr(SPRN_PMC1, pmc_sample_period(sample_period));
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/* XXX Set of MMCR2 must be after enable */
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expected[0] = MMCR2_EXPECTED_1;
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expected[1] = MMCR2_EXPECTED_2;
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i = 0;
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bad_mmcr2 = false;
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/* Make sure we loop until we take at least one EBB */
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while ((ebb_state.stats.ebb_count < 20 && !bad_mmcr2) ||
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ebb_state.stats.ebb_count < 1)
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{
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mtspr(SPRN_MMCR2, expected[i % 2]);
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FAIL_IF(core_busy_loop());
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val = mfspr(SPRN_MMCR2);
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if (val != expected[i % 2]) {
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bad_mmcr2 = true;
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actual = val;
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}
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i++;
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}
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ebb_global_disable();
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ebb_freeze_pmcs();
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count_pmc(1, sample_period);
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dump_ebb_state();
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event_close(&event);
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FAIL_IF(ebb_state.stats.ebb_count == 0);
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if (bad_mmcr2)
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printf("Bad MMCR2 value seen is 0x%lx\n", actual);
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FAIL_IF(bad_mmcr2);
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return 0;
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}
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int main(void)
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{
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return test_harness(cycles_with_mmcr2, "cycles_with_mmcr2");
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}