On 5/6/2024 11:35 AM, Reinette Chatre wrote: ... > diff --git a/tools/testing/selftests/kvm/x86_64/apic_bus_clock_test.c b/tools/testing/selftests/kvm/x86_64/apic_bus_clock_test.c > new file mode 100644 > index 000000000000..56eb686144c6 > --- /dev/null > +++ b/tools/testing/selftests/kvm/x86_64/apic_bus_clock_test.c > @@ -0,0 +1,166 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Test configure of APIC bus frequency. > + * > + * Copyright (c) 2024 Intel Corporation > + * > + * To verify if the APIC bus frequency can be configured this, test starts > + * by setting the TSC frequency in KVM, and then: > + * For every APIC timer frequency supported: > + * * In the guest: > + * * * Start the APIC timer by programming the APIC TMICT (initial count > + * register) to the largest value possible to guarantee that it will > + * not expire during the test, > + * * * Wait for a known duration based on previously set TSC frequency, > + * * * Stop the timer and read the APIC TMCCT (current count) register to > + * determine the count at that time (TMCCT is loaded from TMICT when > + * TMICT is programmed and then starts counting down). > + * * In the host: > + * * * Determine if the APIC counts close to configured APIC bus frequency > + * while taking into account how the APIC timer frequency was modified > + * using the APIC TDCR (divide configuration register). > + */ > +#define _GNU_SOURCE /* for program_invocation_short_name */ As reported in [1] this #define is no longer needed after commit 730cfa45b5f4 ("KVM: selftests: Define _GNU_SOURCE for all selftests code"). This will be fixed in next version of this series. Reinette [1] https://lore.kernel.org/oe-kbuild/202405181535.WFKy4EwQ-lkp@xxxxxxxxx/