// SPDX-License-Identifier: GPL-2.0-only /* * Copyright 2014, Michael Ellerman, IBM Corp. */ #include <stdio.h> #include <stdlib.h> #include "ebb.h" /* * Test that PMC5 & 6 are frozen (ie. don't overflow) when they are not being * used. Tests the MMCR0_FC56 logic in the kernel. */ static int pmc56_overflowed; static void ebb_callee(void) { uint64_t val; val = mfspr(SPRN_BESCR); if (!(val & BESCR_PMEO)) { ebb_state.stats.spurious++; goto out; } ebb_state.stats.ebb_count++; count_pmc(2, sample_period); val = mfspr(SPRN_PMC5); if (val >= COUNTER_OVERFLOW) pmc56_overflowed++; count_pmc(5, COUNTER_OVERFLOW); val = mfspr(SPRN_PMC6); if (val >= COUNTER_OVERFLOW) pmc56_overflowed++; count_pmc(6, COUNTER_OVERFLOW); out: reset_ebb(); } int pmc56_overflow(void) { struct event event; SKIP_IF(!ebb_is_supported()); /* Use PMC2 so we set PMCjCE, which enables PMC5/6 */ event_init(&event, 0x2001e); event_leader_ebb_init(&event); event.attr.exclude_kernel = 1; event.attr.exclude_hv = 1; event.attr.exclude_idle = 1; FAIL_IF(event_open(&event)); setup_ebb_handler(ebb_callee); ebb_global_enable(); FAIL_IF(ebb_event_enable(&event)); mtspr(SPRN_PMC2, pmc_sample_period(sample_period)); mtspr(SPRN_PMC5, 0); mtspr(SPRN_PMC6, 0); while (ebb_state.stats.ebb_count < 10) FAIL_IF(core_busy_loop()); ebb_global_disable(); ebb_freeze_pmcs(); dump_ebb_state(); printf("PMC5/6 overflow %d\n", pmc56_overflowed); event_close(&event); FAIL_IF(ebb_state.stats.ebb_count == 0 || pmc56_overflowed != 0); return 0; } int main(void) { return test_harness(pmc56_overflow, "pmc56_overflow"); }