1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun #include "tests/tests.h"
3*4882a593Smuzhiyun #include "cloexec.h"
4*4882a593Smuzhiyun #include "debug.h"
5*4882a593Smuzhiyun #include "evlist.h"
6*4882a593Smuzhiyun #include "evsel.h"
7*4882a593Smuzhiyun #include "arch-tests.h"
8*4882a593Smuzhiyun #include <internal/lib.h> // page_size
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun #include <signal.h>
11*4882a593Smuzhiyun #include <sys/mman.h>
12*4882a593Smuzhiyun #include <sys/wait.h>
13*4882a593Smuzhiyun #include <errno.h>
14*4882a593Smuzhiyun #include <string.h>
15*4882a593Smuzhiyun
spawn(void)16*4882a593Smuzhiyun static pid_t spawn(void)
17*4882a593Smuzhiyun {
18*4882a593Smuzhiyun pid_t pid;
19*4882a593Smuzhiyun
20*4882a593Smuzhiyun pid = fork();
21*4882a593Smuzhiyun if (pid)
22*4882a593Smuzhiyun return pid;
23*4882a593Smuzhiyun
24*4882a593Smuzhiyun while(1)
25*4882a593Smuzhiyun sleep(5);
26*4882a593Smuzhiyun return 0;
27*4882a593Smuzhiyun }
28*4882a593Smuzhiyun
29*4882a593Smuzhiyun /*
30*4882a593Smuzhiyun * Create an event group that contains both a sampled hardware
31*4882a593Smuzhiyun * (cpu-cycles) and software (intel_cqm/llc_occupancy/) event. We then
32*4882a593Smuzhiyun * wait for the hardware perf counter to overflow and generate a PMI,
33*4882a593Smuzhiyun * which triggers an event read for both of the events in the group.
34*4882a593Smuzhiyun *
35*4882a593Smuzhiyun * Since reading Intel CQM event counters requires sending SMP IPIs, the
36*4882a593Smuzhiyun * CQM pmu needs to handle the above situation gracefully, and return
37*4882a593Smuzhiyun * the last read counter value to avoid triggering a WARN_ON_ONCE() in
38*4882a593Smuzhiyun * smp_call_function_many() caused by sending IPIs from NMI context.
39*4882a593Smuzhiyun */
test__intel_cqm_count_nmi_context(struct test * test __maybe_unused,int subtest __maybe_unused)40*4882a593Smuzhiyun int test__intel_cqm_count_nmi_context(struct test *test __maybe_unused, int subtest __maybe_unused)
41*4882a593Smuzhiyun {
42*4882a593Smuzhiyun struct evlist *evlist = NULL;
43*4882a593Smuzhiyun struct evsel *evsel = NULL;
44*4882a593Smuzhiyun struct perf_event_attr pe;
45*4882a593Smuzhiyun int i, fd[2], flag, ret;
46*4882a593Smuzhiyun size_t mmap_len;
47*4882a593Smuzhiyun void *event;
48*4882a593Smuzhiyun pid_t pid;
49*4882a593Smuzhiyun int err = TEST_FAIL;
50*4882a593Smuzhiyun
51*4882a593Smuzhiyun flag = perf_event_open_cloexec_flag();
52*4882a593Smuzhiyun
53*4882a593Smuzhiyun evlist = evlist__new();
54*4882a593Smuzhiyun if (!evlist) {
55*4882a593Smuzhiyun pr_debug("perf_evlist__new failed\n");
56*4882a593Smuzhiyun return TEST_FAIL;
57*4882a593Smuzhiyun }
58*4882a593Smuzhiyun
59*4882a593Smuzhiyun ret = parse_events(evlist, "intel_cqm/llc_occupancy/", NULL);
60*4882a593Smuzhiyun if (ret) {
61*4882a593Smuzhiyun pr_debug("parse_events failed, is \"intel_cqm/llc_occupancy/\" available?\n");
62*4882a593Smuzhiyun err = TEST_SKIP;
63*4882a593Smuzhiyun goto out;
64*4882a593Smuzhiyun }
65*4882a593Smuzhiyun
66*4882a593Smuzhiyun evsel = evlist__first(evlist);
67*4882a593Smuzhiyun if (!evsel) {
68*4882a593Smuzhiyun pr_debug("evlist__first failed\n");
69*4882a593Smuzhiyun goto out;
70*4882a593Smuzhiyun }
71*4882a593Smuzhiyun
72*4882a593Smuzhiyun memset(&pe, 0, sizeof(pe));
73*4882a593Smuzhiyun pe.size = sizeof(pe);
74*4882a593Smuzhiyun
75*4882a593Smuzhiyun pe.type = PERF_TYPE_HARDWARE;
76*4882a593Smuzhiyun pe.config = PERF_COUNT_HW_CPU_CYCLES;
77*4882a593Smuzhiyun pe.read_format = PERF_FORMAT_GROUP;
78*4882a593Smuzhiyun
79*4882a593Smuzhiyun pe.sample_period = 128;
80*4882a593Smuzhiyun pe.sample_type = PERF_SAMPLE_IP | PERF_SAMPLE_READ;
81*4882a593Smuzhiyun
82*4882a593Smuzhiyun pid = spawn();
83*4882a593Smuzhiyun
84*4882a593Smuzhiyun fd[0] = sys_perf_event_open(&pe, pid, -1, -1, flag);
85*4882a593Smuzhiyun if (fd[0] < 0) {
86*4882a593Smuzhiyun pr_debug("failed to open event\n");
87*4882a593Smuzhiyun goto out;
88*4882a593Smuzhiyun }
89*4882a593Smuzhiyun
90*4882a593Smuzhiyun memset(&pe, 0, sizeof(pe));
91*4882a593Smuzhiyun pe.size = sizeof(pe);
92*4882a593Smuzhiyun
93*4882a593Smuzhiyun pe.type = evsel->attr.type;
94*4882a593Smuzhiyun pe.config = evsel->attr.config;
95*4882a593Smuzhiyun
96*4882a593Smuzhiyun fd[1] = sys_perf_event_open(&pe, pid, -1, fd[0], flag);
97*4882a593Smuzhiyun if (fd[1] < 0) {
98*4882a593Smuzhiyun pr_debug("failed to open event\n");
99*4882a593Smuzhiyun goto out;
100*4882a593Smuzhiyun }
101*4882a593Smuzhiyun
102*4882a593Smuzhiyun /*
103*4882a593Smuzhiyun * Pick a power-of-two number of pages + 1 for the meta-data
104*4882a593Smuzhiyun * page (struct perf_event_mmap_page). See tools/perf/design.txt.
105*4882a593Smuzhiyun */
106*4882a593Smuzhiyun mmap_len = page_size * 65;
107*4882a593Smuzhiyun
108*4882a593Smuzhiyun event = mmap(NULL, mmap_len, PROT_READ, MAP_SHARED, fd[0], 0);
109*4882a593Smuzhiyun if (event == (void *)(-1)) {
110*4882a593Smuzhiyun pr_debug("failed to mmap %d\n", errno);
111*4882a593Smuzhiyun goto out;
112*4882a593Smuzhiyun }
113*4882a593Smuzhiyun
114*4882a593Smuzhiyun sleep(1);
115*4882a593Smuzhiyun
116*4882a593Smuzhiyun err = TEST_OK;
117*4882a593Smuzhiyun
118*4882a593Smuzhiyun munmap(event, mmap_len);
119*4882a593Smuzhiyun
120*4882a593Smuzhiyun for (i = 0; i < 2; i++)
121*4882a593Smuzhiyun close(fd[i]);
122*4882a593Smuzhiyun
123*4882a593Smuzhiyun kill(pid, SIGKILL);
124*4882a593Smuzhiyun wait(NULL);
125*4882a593Smuzhiyun out:
126*4882a593Smuzhiyun evlist__delete(evlist);
127*4882a593Smuzhiyun return err;
128*4882a593Smuzhiyun }
129