Commit 25c2e591 authored by Nikita Shubin's avatar Nikita Shubin Committed by Arnaldo Carvalho de Melo
Browse files

perf tools riscv: Add support for get_cpuid_str function 



The get_cpuid_str function returns the string that contains values of
MVENDORID, MARCHID and MIMPID in hex format separated by coma.

The values themselves are taken from first cpu entry in "/proc/cpuid"
that contains "mvendorid", "marchid" and "mimpid".

Signed-off-by: default avatarNikita Shubin <n.shubin@yadro.com>
Tested-by: default avatarKautuk Consul <kconsul@ventanamicro.com>
Acked-by: default avatarPalmer Dabbelt <palmer@rivosinc.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Anup Patel <anup@brainfault.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-riscv@lists.infradead.org
Cc: linux@yadro.com
Link: https://lore.kernel.org/r/20220815132251.25702-2-nikita.shubin@maquefel.me


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 200204f5

tools/perf/arch/riscv/util/Build

+1 −0
Original line number Diff line number Diff line 
perf-y += perf_regs.o

perf-y += header.o



perf-$(CONFIG_DWARF) += dwarf-regs.o

perf-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o

tools/perf/arch/riscv/util/header.c

0 → 100644
+104 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-only

/*

 * Implementation of get_cpuid().

 *

 * Author: Nikita Shubin <n.shubin@yadro.com>

 */



#include <stdio.h>

#include <stdlib.h>

#include <api/fs/fs.h>

#include <errno.h>

#include "../../util/debug.h"

#include "../../util/header.h"



#define CPUINFO_MVEN	"mvendorid"

#define CPUINFO_MARCH	"marchid"

#define CPUINFO_MIMP	"mimpid"

#define CPUINFO		"/proc/cpuinfo"



static char *_get_field(const char *line)

{

	char *line2, *nl;



	line2 = strrchr(line, ' ');

	if (!line2)

		return NULL;



	line2++;

	nl = strrchr(line, '\n');

	if (!nl)

		return NULL;



	return strndup(line2, nl - line2);

}



static char *_get_cpuid(void)

{

	char *line = NULL;

	char *mvendorid = NULL;

	char *marchid = NULL;

	char *mimpid = NULL;

	char *cpuid = NULL;

	int read;

	unsigned long line_sz;

	FILE *cpuinfo;



	cpuinfo = fopen(CPUINFO, "r");

	if (cpuinfo == NULL)

		return cpuid;



	while ((read = getline(&line, &line_sz, cpuinfo)) != -1) {

		if (!strncmp(line, CPUINFO_MVEN, strlen(CPUINFO_MVEN))) {

			mvendorid = _get_field(line);

			if (!mvendorid)

				goto free;

		} else if (!strncmp(line, CPUINFO_MARCH, strlen(CPUINFO_MARCH))) {

			marchid = _get_field(line);

			if (!marchid)

				goto free;

		} else if (!strncmp(line, CPUINFO_MIMP, strlen(CPUINFO_MIMP))) {

			mimpid = _get_field(line);

			if (!mimpid)

				goto free;



			break;

		}

	}



	if (!mvendorid || !marchid || !mimpid)

		goto free;



	if (asprintf(&cpuid, "%s-%s-%s", mvendorid, marchid, mimpid) < 0)

		cpuid = NULL;



free:

	fclose(cpuinfo);

	free(mvendorid);

	free(marchid);

	free(mimpid);



	return cpuid;

}



int get_cpuid(char *buffer, size_t sz)

{

	char *cpuid = _get_cpuid();

	int ret = 0;



	if (sz < strlen(cpuid)) {

		ret = -EINVAL;

		goto free;

	}



	scnprintf(buffer, sz, "%s", cpuid);

free:

	free(cpuid);

	return ret;

}



char *

get_cpuid_str(struct perf_pmu *pmu __maybe_unused)

{

	return _get_cpuid();

}