[PATCH 3/3] kselftest/arm64: Validate that changing one VL type does not affect another

From: Mark Brown
Date: Thu Jul 13 2023 - 16:12:01 EST


On a system with both SVE and SME when we change one of the VLs this should
not result in a change in the other VL. Add a check that this is in fact
the case to vec-syscfg.

Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
tools/testing/selftests/arm64/fp/vec-syscfg.c | 22 +++++++++++++++++++++-
1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/arm64/fp/vec-syscfg.c b/tools/testing/selftests/arm64/fp/vec-syscfg.c
index 58ea4bde5be7..5f648b97a06f 100644
--- a/tools/testing/selftests/arm64/fp/vec-syscfg.c
+++ b/tools/testing/selftests/arm64/fp/vec-syscfg.c
@@ -554,7 +554,8 @@ static void prctl_set_onexec(struct vec_data *data)
/* For each VQ verify that setting via prctl() does the right thing */
static void prctl_set_all_vqs(struct vec_data *data)
{
- int ret, vq, vl, new_vl;
+ int ret, vq, vl, new_vl, i;
+ int orig_vls[ARRAY_SIZE(vec_data)];
int errors = 0;

if (!data->min_vl || !data->max_vl) {
@@ -563,6 +564,9 @@ static void prctl_set_all_vqs(struct vec_data *data)
return;
}

+ for (i = 0; i < ARRAY_SIZE(vec_data); i++)
+ orig_vls[i] = vec_data[i].rdvl();
+
for (vq = SVE_VQ_MIN; vq <= SVE_VQ_MAX; vq++) {
vl = sve_vl_from_vq(vq);

@@ -585,6 +589,22 @@ static void prctl_set_all_vqs(struct vec_data *data)
errors++;
}

+ /* Did any other VLs change? */
+ for (i = 0; i < ARRAY_SIZE(vec_data); i++) {
+ if (&vec_data[i] == data)
+ continue;
+
+ if (!(getauxval(vec_data[i].hwcap_type) & vec_data[i].hwcap))
+ continue;
+
+ if (vec_data[i].rdvl() != orig_vls[i]) {
+ ksft_print_msg("%s VL changed from %d to %d\n",
+ vec_data[i].name, orig_vls[i],
+ vec_data[i].rdvl());
+ errors++;
+ }
+ }
+
/* Was that the VL we asked for? */
if (new_vl == vl)
continue;

--
2.30.2