function get_cpuid_str returns midr_el1 value from first online cpu available.
Signed-off-by: Ganapatrao Kulkarni <[email protected]> --- tools/perf/arch/arm64/util/Build | 1 + tools/perf/arch/arm64/util/header.c | 51 +++++++++++++++++++++++++++++++++++++ 2 files changed, 52 insertions(+) create mode 100644 tools/perf/arch/arm64/util/header.c diff --git a/tools/perf/arch/arm64/util/Build b/tools/perf/arch/arm64/util/Build index cef6fb3..b1ab72d 100644 --- a/tools/perf/arch/arm64/util/Build +++ b/tools/perf/arch/arm64/util/Build @@ -1,3 +1,4 @@ +libperf-y += header.o libperf-$(CONFIG_DWARF) += dwarf-regs.o libperf-$(CONFIG_LOCAL_LIBUNWIND) += unwind-libunwind.o diff --git a/tools/perf/arch/arm64/util/header.c b/tools/perf/arch/arm64/util/header.c new file mode 100644 index 0000000..c0468fe --- /dev/null +++ b/tools/perf/arch/arm64/util/header.c @@ -0,0 +1,51 @@ +#include <fnmatch.h> +#include <dirent.h> +#include <unistd.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <linux/stringify.h> +#include "header.h" +#include "util.h" + +#define LINUX_SYS_CPU_DIRECTORY "/sys/devices/system/cpu/" +#define MIDR "/regs/identification/midr_el1" + +char *get_cpuid_str(void) +{ + char *buf = malloc(128); + FILE *file; + char *ret = NULL; + int cpu , nr_cpu; + char sys_file[256]; + + sprintf(sys_file, LINUX_SYS_CPU_DIRECTORY"kernel_max"); + + file = fopen(sys_file, "r"); + if (!file) + return ret; + + if (fscanf(file, "%d", &nr_cpu) != 1) + return ret; + + /* kernel_max returns nr_cpu -1 */ + nr_cpu++; + + /*iterate till you read midr of first online cpu */ + for(cpu = 0; cpu < nr_cpu; cpu++) + { + sprintf(sys_file, LINUX_SYS_CPU_DIRECTORY"cpu%d"MIDR, cpu); + file = fopen(sys_file, "r"); + if (file) { + ret = fgets(buf, 128, file); + if (ret) { + buf[strlen(buf)-1] ='\0'; + fclose(file); + return buf; + } + fclose(file); + } + } + free(buf); + return ret; +} -- 1.8.1.4
