1 #include "tests/tests.h"
7 #include "arch-tests.h"
12 static pid_t spawn(void)
26 * Create an event group that contains both a sampled hardware
27 * (cpu-cycles) and software (intel_cqm/llc_occupancy/) event. We then
28 * wait for the hardware perf counter to overflow and generate a PMI,
29 * which triggers an event read for both of the events in the group.
31 * Since reading Intel CQM event counters requires sending SMP IPIs, the
32 * CQM pmu needs to handle the above situation gracefully, and return
33 * the last read counter value to avoid triggering a WARN_ON_ONCE() in
34 * smp_call_function_many() caused by sending IPIs from NMI context.
36 int test__intel_cqm_count_nmi_context(int subtest __maybe_unused)
38 struct perf_evlist *evlist = NULL;
39 struct perf_evsel *evsel = NULL;
40 struct perf_event_attr pe;
41 int i, fd[2], flag, ret;
47 flag = perf_event_open_cloexec_flag();
49 evlist = perf_evlist__new();
51 pr_debug("perf_evlist__new failed\n");
55 ret = parse_events(evlist, "intel_cqm/llc_occupancy/", NULL);
57 pr_debug("parse_events failed, is \"intel_cqm/llc_occupancy/\" available?\n");
62 evsel = perf_evlist__first(evlist);
64 pr_debug("perf_evlist__first failed\n");
68 memset(&pe, 0, sizeof(pe));
71 pe.type = PERF_TYPE_HARDWARE;
72 pe.config = PERF_COUNT_HW_CPU_CYCLES;
73 pe.read_format = PERF_FORMAT_GROUP;
75 pe.sample_period = 128;
76 pe.sample_type = PERF_SAMPLE_IP | PERF_SAMPLE_READ;
80 fd[0] = sys_perf_event_open(&pe, pid, -1, -1, flag);
82 pr_debug("failed to open event\n");
86 memset(&pe, 0, sizeof(pe));
89 pe.type = evsel->attr.type;
90 pe.config = evsel->attr.config;
92 fd[1] = sys_perf_event_open(&pe, pid, -1, fd[0], flag);
94 pr_debug("failed to open event\n");
99 * Pick a power-of-two number of pages + 1 for the meta-data
100 * page (struct perf_event_mmap_page). See tools/perf/design.txt.
102 mmap_len = page_size * 65;
104 event = mmap(NULL, mmap_len, PROT_READ, MAP_SHARED, fd[0], 0);
105 if (event == (void *)(-1)) {
106 pr_debug("failed to mmap %d\n", errno);
114 munmap(event, mmap_len);
116 for (i = 0; i < 2; i++)
122 perf_evlist__delete(evlist);