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author | Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com> | 2017-10-17 00:02:19 +0530 |
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committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2017-12-05 10:24:33 -0300 |
commit | b57df28893543db3466172088786fae39b7fc3ad (patch) | |
tree | 16dc6a6030e6e38b0396cd12880c08e9e1bf9ef4 /tools/perf/arch | |
parent | 54e32dc0f89ec7fcb87df6c45b096e57f050f22b (diff) | |
download | linux-b57df28893543db3466172088786fae39b7fc3ad.tar.bz2 |
perf tools arm64: Add support for get_cpuid_str function.
The get_cpuid_str function returns the MIDR string of the first online
cpu from the range of cpus associated with the PMU CORE device.
Signed-off-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Ganapatrao Kulkarni <gklkml16@gmail.com>
Cc: Jayachandran C <jnair@caviumnetworks.com>
Cc: Jonathan Cameron <jonathan.cameron@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert Richter <robert.richter@cavium.com>
Cc: Shaokun Zhang <zhangshaokun@hisilicon.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20171016183222.25750-3-ganapatrao.kulkarni@cavium.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/arch')
-rw-r--r-- | tools/perf/arch/arm64/util/Build | 1 | ||||
-rw-r--r-- | tools/perf/arch/arm64/util/header.c | 65 |
2 files changed, 66 insertions, 0 deletions
diff --git a/tools/perf/arch/arm64/util/Build b/tools/perf/arch/arm64/util/Build index cef6fb38d17e..b1ab72d2a42e 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 000000000000..534cd2507d83 --- /dev/null +++ b/tools/perf/arch/arm64/util/header.c @@ -0,0 +1,65 @@ +#include <stdio.h> +#include <stdlib.h> +#include <api/fs/fs.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 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 = cpu_map__get(pmu->cpus); + for (cpu = 0; cpu < cpus->nr; 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; + } + + cpu_map__put(cpus); + return buf; +} |