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
);