On Fri, 26 Aug 2022 10:49:44 +0200 Nico Boehr <nrb@xxxxxxxxxxxxx> wrote: > On migration, we expect the guest clock value to be preserved. Add a > test to verify this: > - advance the guest TOD by much more than we need to migrate > - migrate the guest > - get the guest TOD > > After migration, assert the guest TOD value is at least the value we set > before migration. > > Signed-off-by: Nico Boehr <nrb@xxxxxxxxxxxxx> > --- > s390x/Makefile | 1 + > s390x/migration-sck.c | 45 +++++++++++++++++++++++++++++++++++++++++++ > s390x/unittests.cfg | 4 ++++ > 3 files changed, 50 insertions(+) > create mode 100644 s390x/migration-sck.c > > diff --git a/s390x/Makefile b/s390x/Makefile > index efd5e0c13102..be8e647bb35f 100644 > --- a/s390x/Makefile > +++ b/s390x/Makefile > @@ -34,6 +34,7 @@ tests += $(TEST_DIR)/migration.elf > tests += $(TEST_DIR)/pv-attest.elf > tests += $(TEST_DIR)/migration-cmm.elf > tests += $(TEST_DIR)/migration-skey.elf > +tests += $(TEST_DIR)/migration-sck.elf > > pv-tests += $(TEST_DIR)/pv-diags.elf > > diff --git a/s390x/migration-sck.c b/s390x/migration-sck.c > new file mode 100644 > index 000000000000..701d33f9db5a > --- /dev/null > +++ b/s390x/migration-sck.c > @@ -0,0 +1,45 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > +/* > + * SET CLOCK migration tests > + * > + * Copyright IBM Corp. 2022 > + * > + * Authors: > + * Nico Boehr <nrb@xxxxxxxxxxxxx> > + */ > + > +#include <libcflat.h> > +#include <asm/time.h> > +#include <bitops.h> > + > +static void test_sck_migration(void) > +{ > + uint64_t now_before_set = 0, now_after_migration, time_to_set, time_to_advance; > + int cc; > + > + stckf(&now_before_set); > + > + /* Advance the clock by a lot more than we might ever need to migrate (60s) */ maybe give an even bigger value, just to be really sure. like 600s > + time_to_advance = (60ULL * 1000ULL * 1000ULL << STCK_SHIFT_US); you can do * 1000000, and you don't need ULL everywhere; use the braces to help humans understand what's going on: time_to_advance = (600ULL * 1000000) << STCK_SHIFT_US; > + time_to_set = now_before_set + time_to_advance; > + > + cc = sck(&time_to_set); > + report(!cc, "setting clock succeeded"); > + > + puts("Please migrate me, then press return\n"); > + (void)getchar(); > + > + cc = stckf(&now_after_migration); > + report(!cc, "clock still set"); > + > + report(now_after_migration >= time_to_set, "TOD clock value preserved"); > +} > + > +int main(void) > +{ > + report_prefix_push("migration-sck"); > + > + test_sck_migration(); > + report_prefix_pop(); > + return report_summary(); > +} > diff --git a/s390x/unittests.cfg b/s390x/unittests.cfg > index f7b1fc3dbca1..808e8a28ba96 100644 > --- a/s390x/unittests.cfg > +++ b/s390x/unittests.cfg > @@ -185,3 +185,7 @@ groups = migration > [migration-skey] > file = migration-skey.elf > groups = migration > + > +[migration-sck] > +file = migration-sck.elf > +groups = migration