// SPDX-License-Identifier: GPL-2.0-only /* * Copyright 2014, Michael Ellerman, IBM Corp. */ #include <stdio.h> #include <stdlib.h> #include <setjmp.h> #include <signal.h> #include "ebb.h" /* * Test that closing the EBB event clears MMCR0_PMCC, preventing further access * by userspace to the PMU hardware. */ int close_clears_pmcc(void) { struct event event; SKIP_IF(!ebb_is_supported()); event_init_named(&event, 0x1001e, "cycles"); event_leader_ebb_init(&event); FAIL_IF(event_open(&event)); ebb_enable_pmc_counting(1); setup_ebb_handler(standard_ebb_callee); ebb_global_enable(); FAIL_IF(ebb_event_enable(&event)); mtspr(SPRN_PMC1, pmc_sample_period(sample_period)); while (ebb_state.stats.ebb_count < 1) FAIL_IF(core_busy_loop()); ebb_global_disable(); event_close(&event); FAIL_IF(ebb_state.stats.ebb_count == 0); /* The real test is here, do we take a SIGILL when writing PMU regs now * that we have closed the event. We expect that we will. */ FAIL_IF(catch_sigill(write_pmc1)); /* We should still be able to read EBB regs though */ mfspr(SPRN_EBBHR); mfspr(SPRN_EBBRR); mfspr(SPRN_BESCR); return 0; } int main(void) { return test_harness(close_clears_pmcc, "close_clears_pmcc"); } |