tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
selftests: vdso: Add a selftest for vDSO getcpu()
Provide a very basic selftest for getcpu() which similarly to our existing
test for gettimeofday() looks up the function in the vDSO and prints the
results it gets if the function exists and succeeds.
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
authored by
Mark Brown
and committed by
Shuah Khan
2e9a9725
cd76ca4d
+57
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tools/testing/selftests/vDSO/.gitignore
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tools/testing/selftests/vDSO/.gitignore
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-1
tools/testing/selftests/vDSO/Makefile
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tools/testing/selftests/vDSO/Makefile
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uname_M := $(shell uname -m 2>/dev/null || echo not)
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ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/x86/ -e s/x86_64/x86/)
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TEST_GEN_PROGS := $(OUTPUT)/vdso_test_gettimeofday
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TEST_GEN_PROGS := $(OUTPUT)/vdso_test_gettimeofday $(OUTPUT)/vdso_test_getcpu
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ifeq ($(ARCH),x86)
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TEST_GEN_PROGS += $(OUTPUT)/vdso_standalone_test_x86
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endif
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all: $(TEST_GEN_PROGS)
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$(OUTPUT)/vdso_test_gettimeofday: parse_vdso.c vdso_test_gettimeofday.c
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$(OUTPUT)/vdso_test_getcpu: parse_vdso.c vdso_test_getcpu.c
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$(OUTPUT)/vdso_standalone_test_x86: vdso_standalone_test_x86.c parse_vdso.c
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$(CC) $(CFLAGS) $(CFLAGS_vdso_standalone_test_x86) \
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vdso_standalone_test_x86.c parse_vdso.c \
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tools/testing/selftests/vDSO/vdso_test_getcpu.c
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tools/testing/selftests/vDSO/vdso_test_getcpu.c
···
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// SPDX-License-Identifier: GPL-2.0-only
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/*
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* vdso_test_getcpu.c: Sample code to test parse_vdso.c and vDSO getcpu()
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*
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* Copyright (c) 2020 Arm Ltd
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*/
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#include <stdint.h>
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#include <elf.h>
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#include <stdio.h>
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#include <sys/auxv.h>
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#include <sys/time.h>
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#include "../kselftest.h"
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#include "parse_vdso.h"
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const char *version = "LINUX_2.6";
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const char *name = "__vdso_getcpu";
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struct getcpu_cache;
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typedef long (*getcpu_t)(unsigned int *, unsigned int *,
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struct getcpu_cache *);
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int main(int argc, char **argv)
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{
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unsigned long sysinfo_ehdr;
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unsigned int cpu, node;
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getcpu_t get_cpu;
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long ret;
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sysinfo_ehdr = getauxval(AT_SYSINFO_EHDR);
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if (!sysinfo_ehdr) {
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printf("AT_SYSINFO_EHDR is not present!\n");
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return KSFT_SKIP;
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}
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vdso_init_from_sysinfo_ehdr(getauxval(AT_SYSINFO_EHDR));
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get_cpu = (getcpu_t)vdso_sym(version, name);
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if (!get_cpu) {
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printf("Could not find %s\n", name);
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return KSFT_SKIP;
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}
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ret = get_cpu(&cpu, &node, 0);
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if (ret == 0) {
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printf("Running on CPU %u node %u\n", cpu, node);
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} else {
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printf("%s failed\n", name);
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return KSFT_FAIL;
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}
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return 0;
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}