Home | History | Annotate | Download | only in ebb
      1 /*
      2  * Copyright 2014, Michael Ellerman, IBM Corp.
      3  * Licensed under GPLv2.
      4  */
      5 
      6 #include <stdio.h>
      7 #include <stdlib.h>
      8 #include <setjmp.h>
      9 #include <signal.h>
     10 
     11 #include "ebb.h"
     12 
     13 
     14 /*
     15  * Test that closing the EBB event clears MMCR0_PMCC, preventing further access
     16  * by userspace to the PMU hardware.
     17  */
     18 
     19 int close_clears_pmcc(void)
     20 {
     21 	struct event event;
     22 
     23 	SKIP_IF(!ebb_is_supported());
     24 
     25 	event_init_named(&event, 0x1001e, "cycles");
     26 	event_leader_ebb_init(&event);
     27 
     28 	FAIL_IF(event_open(&event));
     29 
     30 	ebb_enable_pmc_counting(1);
     31 	setup_ebb_handler(standard_ebb_callee);
     32 	ebb_global_enable();
     33 	FAIL_IF(ebb_event_enable(&event));
     34 
     35 	mtspr(SPRN_PMC1, pmc_sample_period(sample_period));
     36 
     37 	while (ebb_state.stats.ebb_count < 1)
     38 		FAIL_IF(core_busy_loop());
     39 
     40 	ebb_global_disable();
     41 	event_close(&event);
     42 
     43 	FAIL_IF(ebb_state.stats.ebb_count == 0);
     44 
     45 	/* The real test is here, do we take a SIGILL when writing PMU regs now
     46 	 * that we have closed the event. We expect that we will. */
     47 
     48 	FAIL_IF(catch_sigill(write_pmc1));
     49 
     50 	/* We should still be able to read EBB regs though */
     51 	mfspr(SPRN_EBBHR);
     52 	mfspr(SPRN_EBBRR);
     53 	mfspr(SPRN_BESCR);
     54 
     55 	return 0;
     56 }
     57 
     58 int main(void)
     59 {
     60 	return test_harness(close_clears_pmcc, "close_clears_pmcc");
     61 }
     62