Re: [PATCH v5 3/6] perf test: Add a test for the new Arm CPU ID comparison behavior

[John Garry <john.g.garry@oracle.com>]

On 11/08/2023 15:39, James Clark wrote:
> Now that variant and revision fields are taken into account the behavior
> is slightly more complicated so add a test to ensure that this behaves
> as expected.
> 
> Signed-off-by: James Clark <james.clark@arm.com>
> ---
>   tools/perf/arch/arm64/include/arch-tests.h |  3 ++
>   tools/perf/arch/arm64/tests/Build          |  1 +
>   tools/perf/arch/arm64/tests/arch-tests.c   |  4 +++
>   tools/perf/arch/arm64/tests/cpuid-match.c  | 38 ++++++++++++++++++++++
>   4 files changed, 46 insertions(+)
>   create mode 100644 tools/perf/arch/arm64/tests/cpuid-match.c
> 
> diff --git a/tools/perf/arch/arm64/include/arch-tests.h b/tools/perf/arch/arm64/include/arch-tests.h
> index 452b3d904521..474d7cf5afbd 100644
> --- a/tools/perf/arch/arm64/include/arch-tests.h
> +++ b/tools/perf/arch/arm64/include/arch-tests.h
> @@ -2,6 +2,9 @@
>   #ifndef ARCH_TESTS_H
>   #define ARCH_TESTS_H
>   
> +struct test_suite;
> +
> +int test__cpuid_match(struct test_suite *test, int subtest);
>   extern struct test_suite *arch_tests[];
>   
>   #endif
> diff --git a/tools/perf/arch/arm64/tests/Build b/tools/perf/arch/arm64/tests/Build
> index a61c06bdb757..e337c09e7f56 100644
> --- a/tools/perf/arch/arm64/tests/Build
> +++ b/tools/perf/arch/arm64/tests/Build
> @@ -2,3 +2,4 @@ perf-y += regs_load.o
>   perf-$(CONFIG_DWARF_UNWIND) += dwarf-unwind.o
>   
>   perf-y += arch-tests.o
> +perf-y += cpuid-match.o
> diff --git a/tools/perf/arch/arm64/tests/arch-tests.c b/tools/perf/arch/arm64/tests/arch-tests.c
> index ad16b4f8f63e..74932e72c727 100644
> --- a/tools/perf/arch/arm64/tests/arch-tests.c
> +++ b/tools/perf/arch/arm64/tests/arch-tests.c
> @@ -3,9 +3,13 @@
>   #include "tests/tests.h"
>   #include "arch-tests.h"
>   
> +
> +DEFINE_SUITE("arm64 CPUID matching", cpuid_match);
> +
>   struct test_suite *arch_tests[] = {
>   #ifdef HAVE_DWARF_UNWIND_SUPPORT
>   	&suite__dwarf_unwind,
>   #endif
> +	&suite__cpuid_match,
>   	NULL,
>   };
> diff --git a/tools/perf/arch/arm64/tests/cpuid-match.c b/tools/perf/arch/arm64/tests/cpuid-match.c
> new file mode 100644
> index 000000000000..af0871b54ae7
> --- /dev/null
> +++ b/tools/perf/arch/arm64/tests/cpuid-match.c
> @@ -0,0 +1,38 @@
> +// SPDX-License-Identifier: GPL-2.0
> +#include <linux/compiler.h>
> +
> +#include "arch-tests.h"
> +#include "tests/tests.h"
> +#include "util/header.h"
> +
> +int test__cpuid_match(struct test_suite *test __maybe_unused,
> +			     int subtest __maybe_unused)
> +{
> +	/* midr with no leading zeros matches */
> +	if (strcmp_cpuid_str("0x410fd0c0", "0x00000000410fd0c0"))
> +		return -1;
> +	/* Upper case matches */
> +	if (strcmp_cpuid_str("0x410fd0c0", "0x00000000410FD0C0"))
> +		return -1;
> +	/* r0p0 = r0p0 matches */
> +	if (strcmp_cpuid_str("0x00000000410fd480", "0x00000000410fd480"))
> +		return -1;
> +	/* r0p1 > r0p0 matches */
> +	if (strcmp_cpuid_str("0x00000000410fd480", "0x00000000410fd481"))
> +		return -1;
> +	/* r1p0 > r0p0 matches*/
> +	if (strcmp_cpuid_str("0x00000000410fd480", "0x00000000411fd480"))
> +		return -1;
> +	/* r0p0 < r0p1 doesn't match */
> +	if (!strcmp_cpuid_str("0x00000000410fd481", "0x00000000410fd480"))
> +		return -1;
> +	/* r0p0 < r1p0 doesn't match */
> +	if (!strcmp_cpuid_str("0x00000000411fd480", "0x00000000410fd480"))
> +		return -1;
> +	/* Different CPU doesn't match */
> +	if (!strcmp_cpuid_str("0x00000000410fd4c0", "0x00000000430f0af0"))
> +		return -1;
> +
> +	return 0;
> +}
> +

Would it be possible to put this in core test code, since x86 also 
supports strcmp_cpuid_str()?

Maybe we would have an structure per arch of cpuids and expected 
results, like

struct cpuid_match {
	char *cpuid1;
	char *cpuid1;
	int expected_result;
};


#ifdef ARM64
  cpuid_match_array[] = {
	{"0x410fd0c0", "0x00000000410FD0C0", -1},
	{"0x00000000410fd480", "0x00000000410fd480", -1},
	...
	{} /* sentinel */

};
#else if defined(X86)
  cpuid_match_array[] = {
	{....}
	...
	{} /* sentinel */

};
#else
/* no support */
#endif

Thanks,
John