xref: /linux/tools/perf/arch/arm64/util/pmu.c (revision 69bfec7548f4c1595bac0e3ddfc0458a5af31f4c)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 #include <internal/cpumap.h>
4 #include "../../../util/cpumap.h"
5 #include "../../../util/pmu.h"
6 #include <api/fs/fs.h>
7 #include <math.h>
8 
9 static struct perf_pmu *pmu__find_core_pmu(void)
10 {
11 	struct perf_pmu *pmu = NULL;
12 
13 	while ((pmu = perf_pmu__scan(pmu))) {
14 		if (!is_pmu_core(pmu->name))
15 			continue;
16 
17 		/*
18 		 * The cpumap should cover all CPUs. Otherwise, some CPUs may
19 		 * not support some events or have different event IDs.
20 		 */
21 		if (pmu->cpus->nr != cpu__max_cpu().cpu)
22 			return NULL;
23 
24 		return pmu;
25 	}
26 	return NULL;
27 }
28 
29 const struct pmu_metrics_table *pmu_metrics_table__find(void)
30 {
31 	struct perf_pmu *pmu = pmu__find_core_pmu();
32 
33 	if (pmu)
34 		return perf_pmu__find_metrics_table(pmu);
35 
36 	return NULL;
37 }
38 
39 const struct pmu_events_table *pmu_events_table__find(void)
40 {
41 	struct perf_pmu *pmu = pmu__find_core_pmu();
42 
43 	if (pmu)
44 		return perf_pmu__find_events_table(pmu);
45 
46 	return NULL;
47 }
48 
49 double perf_pmu__cpu_slots_per_cycle(void)
50 {
51 	char path[PATH_MAX];
52 	unsigned long long slots = 0;
53 	struct perf_pmu *pmu = pmu__find_core_pmu();
54 
55 	if (pmu) {
56 		perf_pmu__pathname_scnprintf(path, sizeof(path),
57 					     pmu->name, "caps/slots");
58 		/*
59 		 * The value of slots is not greater than 32 bits, but sysfs__read_int
60 		 * can't read value with 0x prefix, so use sysfs__read_ull instead.
61 		 */
62 		sysfs__read_ull(path, &slots);
63 	}
64 
65 	return slots ? (double)slots : NAN;
66 }
67