| Message ID | 20230214184606.510551-3-mizhang@google.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Overhauling amx_test | expand |
On Tue, Feb 14, 2023 at 06:46:01PM +0000, Mingwei Zhang wrote: >After the execution of __tilerelease(), AMX component will be in INIT >state. Therefore, execution of XSAVEC saving the AMX state into memory will >cause the xstate_bv[18] cleared in xheader. However, the xcomp_bv[18] will >remain set. Fix the error in comment. Also, update xsavec() to XSAVEC >because xcomp_bv[18] is set due to the instruction, not the function. >Finally, use XTILEDATA instead 'bit 18' in comments. > >Cc: Jim Mattson <jmattson@google.com> >Cc: Venkatesh Srinivas <venkateshs@google.com> >Cc: Aaron Lewis <aaronlewis@google.com> >Signed-off-by: Mingwei Zhang <mizhang@google.com> >--- > tools/testing/selftests/kvm/x86_64/amx_test.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > >diff --git a/tools/testing/selftests/kvm/x86_64/amx_test.c b/tools/testing/selftests/kvm/x86_64/amx_test.c >index d506821a5a26..aac727ff7cf8 100644 >--- a/tools/testing/selftests/kvm/x86_64/amx_test.c >+++ b/tools/testing/selftests/kvm/x86_64/amx_test.c >@@ -190,7 +190,10 @@ static void __attribute__((__flatten__)) guest_code(struct tile_config *amx_cfg, > GUEST_SYNC(4); > __tilerelease(); > GUEST_SYNC(5); >- /* bit 18 not in the XCOMP_BV after xsavec() */ >+ /* >+ * After XSAVEC, XTILEDATA is cleared in the xstate_bv but is set in >+ * the xcomp_bv. >+ */ > xstate->header.xstate_bv = XFEATURE_MASK_XTILEDATA; > __xsavec(xstate, XFEATURE_MASK_XTILEDATA); > GUEST_ASSERT(!(xstate->header.xstate_bv & XFEATURE_MASK_XTILEDATA)); maybe it would be better to add another GUEST_ASSERT() to enforce that XTILEDATA is set in the xcomp_bv. >-- >2.39.1.581.gbfd45094c4-goog >
On Sun, Feb 19, 2023, Chao Gao wrote: > On Tue, Feb 14, 2023 at 06:46:01PM +0000, Mingwei Zhang wrote: > >After the execution of __tilerelease(), AMX component will be in INIT > >state. Therefore, execution of XSAVEC saving the AMX state into memory will > >cause the xstate_bv[18] cleared in xheader. However, the xcomp_bv[18] will > >remain set. Fix the error in comment. Also, update xsavec() to XSAVEC > >because xcomp_bv[18] is set due to the instruction, not the function. > >Finally, use XTILEDATA instead 'bit 18' in comments. > > > >Cc: Jim Mattson <jmattson@google.com> > >Cc: Venkatesh Srinivas <venkateshs@google.com> > >Cc: Aaron Lewis <aaronlewis@google.com> > >Signed-off-by: Mingwei Zhang <mizhang@google.com> > >--- > > tools/testing/selftests/kvm/x86_64/amx_test.c | 5 ++++- > > 1 file changed, 4 insertions(+), 1 deletion(-) > > > >diff --git a/tools/testing/selftests/kvm/x86_64/amx_test.c b/tools/testing/selftests/kvm/x86_64/amx_test.c > >index d506821a5a26..aac727ff7cf8 100644 > >--- a/tools/testing/selftests/kvm/x86_64/amx_test.c > >+++ b/tools/testing/selftests/kvm/x86_64/amx_test.c > >@@ -190,7 +190,10 @@ static void __attribute__((__flatten__)) guest_code(struct tile_config *amx_cfg, > > GUEST_SYNC(4); > > __tilerelease(); > > GUEST_SYNC(5); > >- /* bit 18 not in the XCOMP_BV after xsavec() */ > >+ /* > >+ * After XSAVEC, XTILEDATA is cleared in the xstate_bv but is set in > >+ * the xcomp_bv. > >+ */ > > xstate->header.xstate_bv = XFEATURE_MASK_XTILEDATA; > > __xsavec(xstate, XFEATURE_MASK_XTILEDATA); > > GUEST_ASSERT(!(xstate->header.xstate_bv & XFEATURE_MASK_XTILEDATA)); > > maybe it would be better to add another GUEST_ASSERT() to enforce that > XTILEDATA is set in the xcomp_bv. yeah. The check has been added in the 6th patch of the series, but I think it is hard to see. I will reorder the change next to this one in the next version. > > >-- > >2.39.1.581.gbfd45094c4-goog > >
diff --git a/tools/testing/selftests/kvm/x86_64/amx_test.c b/tools/testing/selftests/kvm/x86_64/amx_test.c index d506821a5a26..aac727ff7cf8 100644 --- a/tools/testing/selftests/kvm/x86_64/amx_test.c +++ b/tools/testing/selftests/kvm/x86_64/amx_test.c @@ -190,7 +190,10 @@ static void __attribute__((__flatten__)) guest_code(struct tile_config *amx_cfg, GUEST_SYNC(4); __tilerelease(); GUEST_SYNC(5); - /* bit 18 not in the XCOMP_BV after xsavec() */ + /* + * After XSAVEC, XTILEDATA is cleared in the xstate_bv but is set in + * the xcomp_bv. + */ xstate->header.xstate_bv = XFEATURE_MASK_XTILEDATA; __xsavec(xstate, XFEATURE_MASK_XTILEDATA); GUEST_ASSERT(!(xstate->header.xstate_bv & XFEATURE_MASK_XTILEDATA));
After the execution of __tilerelease(), AMX component will be in INIT state. Therefore, execution of XSAVEC saving the AMX state into memory will cause the xstate_bv[18] cleared in xheader. However, the xcomp_bv[18] will remain set. Fix the error in comment. Also, update xsavec() to XSAVEC because xcomp_bv[18] is set due to the instruction, not the function. Finally, use XTILEDATA instead 'bit 18' in comments. Cc: Jim Mattson <jmattson@google.com> Cc: Venkatesh Srinivas <venkateshs@google.com> Cc: Aaron Lewis <aaronlewis@google.com> Signed-off-by: Mingwei Zhang <mizhang@google.com> --- tools/testing/selftests/kvm/x86_64/amx_test.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)