Re: [PATCH v5 3/6] perf test: Add a test for the new Arm CPU ID comparison behavior
From: James Clark
Date: Wed Aug 16 2023 - 05:15:30 EST
On 15/08/2023 10:47, John Garry wrote:
> 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@xxxxxxx>
>> ---
>> 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()?
>
That's how I started, but Ian suggested to move it to an arch specific
folder because that's what it was testing.
We could still add test__cpuid_match() in the x86 folder rather than
adding it with #ifdefs, but I don't think it needs to be done here
because I haven't touched the x86 code.
> 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