KVM: arm64: selftests: Remove a duplicate register listing in set_id_regs

Currently we list the main set of registers with bits we test three
times, once in the test_regs array which is used at runtime, once in the
guest code and once in a list of ARRAY_SIZE() operations we use to tell
kselftest how many tests we plan to execute. This is needlessly fiddly,
when adding new registers as the test_cnt calculation is formatted with
two registers per line. Instead count the number of bitfields in the
register arrays at runtime.

The existing code subtracts ARRAY_SIZE(test_regs) from the number of
tests to account for the terminating FTR_REG_END entries in the per
register arrays, the new code accounts for this when enumerating.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>

Author: broonie

tools/testing/selftests/kvm/arm64/set_id_regs.c

@@ -753,7 +753,7 @@ int main(void)
 	struct kvm_vm *vm;
 	bool aarch64_only;
 	uint64_t val, el0;
-	int test_cnt;
+	int test_cnt, i, j;
 
 	TEST_REQUIRE(kvm_has_cap(KVM_CAP_ARM_SUPPORTED_REG_MASK_RANGES));
 	TEST_REQUIRE(kvm_has_cap(KVM_CAP_ARM_WRITABLE_IMP_ID_REGS));
@@ -772,13 +772,10 @@ int main(void)
 
 	ksft_print_header();
 
-	test_cnt = ARRAY_SIZE(ftr_id_aa64dfr0_el1) + ARRAY_SIZE(ftr_id_dfr0_el1) +
-		   ARRAY_SIZE(ftr_id_aa64isar0_el1) + ARRAY_SIZE(ftr_id_aa64isar1_el1) +
-		   ARRAY_SIZE(ftr_id_aa64isar2_el1) + ARRAY_SIZE(ftr_id_aa64pfr0_el1) +
-		   ARRAY_SIZE(ftr_id_aa64pfr1_el1) + ARRAY_SIZE(ftr_id_aa64mmfr0_el1) +
-		   ARRAY_SIZE(ftr_id_aa64mmfr1_el1) + ARRAY_SIZE(ftr_id_aa64mmfr2_el1) +
-		   ARRAY_SIZE(ftr_id_aa64mmfr3_el1) + ARRAY_SIZE(ftr_id_aa64zfr0_el1) -
-		   ARRAY_SIZE(test_regs) + 3 + MPAM_IDREG_TEST + MTE_IDREG_TEST;
+	test_cnt = 3 + MPAM_IDREG_TEST + MTE_IDREG_TEST;
+	for (i = 0; i < ARRAY_SIZE(test_regs); i++)
+		for (j = 0; test_regs[i].ftr_bits[j].type != FTR_END; j++)
+			test_cnt++;
 
 	ksft_set_plan(test_cnt);