1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright 2022, Madhavan Srinivasan, IBM Corp.
4 */
5
6#include <signal.h>
7#include <stdio.h>
8#include <stdlib.h>
9#include <sys/types.h>
10
11#include "../event.h"
12#include "misc.h"
13#include "utils.h"
14
15extern void thirty_two_instruction_loop(int loops);
16
17static bool is_hv;
18
19static void sig_usr2_handler(int signum, siginfo_t *info, void *data)
20{
21 ucontext_t *uctx = data;
22
23 is_hv = !!(uctx->uc_mcontext.gp_regs[PT_MSR] & MSR_HV);
24}
25
26/*
27 * A perf sampling test for mmcr2
28 * fields : fcs, fch.
29 */
30static int mmcr2_fcs_fch(void)
31{
32 struct sigaction sigact = {
33 .sa_sigaction = sig_usr2_handler,
34 .sa_flags = SA_SIGINFO
35 };
36 struct event event;
37 u64 *intr_regs;
38
39 FAIL_IF(sigaction(SIGUSR2, &sigact, NULL));
40 FAIL_IF(kill(getpid(), SIGUSR2));
41
42 /* Check for platform support for the test */
43 SKIP_IF(check_pvr_for_sampling_tests());
44
45 /* Init the event for the sampling test */
46 event_init_sampling(e: &event, config: 0x1001e);
47 event.attr.sample_regs_intr = platform_extended_mask;
48 event.attr.exclude_kernel = 1;
49 FAIL_IF(event_open(e: &event));
50 event.mmap_buffer = event_sample_buf_mmap(fd: event.fd, mmap_pages: 1);
51
52 FAIL_IF(event_enable(e: &event));
53
54 /* workload to make the event overflow */
55 thirty_two_instruction_loop(loops: 10000);
56
57 FAIL_IF(event_disable(e: &event));
58
59 /* Check for sample count */
60 FAIL_IF(!collect_samples(sample_buff: event.mmap_buffer));
61
62 intr_regs = get_intr_regs(event: &event, sample_buff: event.mmap_buffer);
63
64 /* Check for intr_regs */
65 FAIL_IF(!intr_regs);
66
67 /*
68 * Verify that fcs and fch field of MMCR2 match
69 * with corresponding modifier fields.
70 */
71 if (is_hv)
72 FAIL_IF(event.attr.exclude_kernel !=
73 get_mmcr2_fch(mmcr2: get_reg_value(intr_regs, register_name: "MMCR2"), pmc: 1));
74 else
75 FAIL_IF(event.attr.exclude_kernel !=
76 get_mmcr2_fcs(mmcr2: get_reg_value(intr_regs, register_name: "MMCR2"), pmc: 1));
77
78 event_close(e: &event);
79 return 0;
80}
81
82int main(void)
83{
84 return test_harness(mmcr2_fcs_fch, "mmcr2_fcs_fch");
85}
86

source code of linux/tools/testing/selftests/powerpc/pmu/sampling_tests/mmcr2_fcs_fch_test.c