#include <stdio.h> #include <stdlib.h> #include <perf/cpumap.h> #include <internal/cpumap.h> #include <api/fs/fs.h> #include "debug.h" #include "header.h" #define MIDR "/regs/identification/midr_el1" #define MIDR_SIZE 19 #define MIDR_REVISION_MASK 0xf #define MIDR_VARIANT_SHIFT 20 #define MIDR_VARIANT_MASK (0xf << MIDR_VARIANT_SHIFT) char *get_cpuid_str(struct perf_pmu *pmu) { char *buf = NULL; char path[PATH_MAX]; const char *sysfs = sysfs__mountpoint(); int cpu; u64 midr = 0; struct perf_cpu_map *cpus; FILE *file; if (!sysfs || !pmu || !pmu->cpus) return NULL; buf = malloc(MIDR_SIZE); if (!buf) return NULL; /* read midr from list of cpus mapped to this pmu */ cpus = perf_cpu_map__get(pmu->cpus); for (cpu = 0; cpu < perf_cpu_map__nr(cpus); cpu++) { scnprintf(path, PATH_MAX, "%s/devices/system/cpu/cpu%d"MIDR, sysfs, cpus->map[cpu]); file = fopen(path, "r"); if (!file) { pr_debug("fopen failed for file %s\n", path); continue; } if (!fgets(buf, MIDR_SIZE, file)) { fclose(file); continue; } fclose(file); /* Ignore/clear Variant[23:20] and * Revision[3:0] of MIDR */ midr = strtoul(buf, NULL, 16); midr &= (~(MIDR_VARIANT_MASK | MIDR_REVISION_MASK)); scnprintf(buf, MIDR_SIZE, "0x%016lx", midr); /* got midr break loop */ break; } if (!midr) { pr_err("failed to get cpuid string for PMU %s\n", pmu->name); free(buf); buf = NULL; } perf_cpu_map__put(cpus); return buf; }