Add a new selftests that validates some edge cases related to the virtual arch-timer, for example: - timers across counter roll-overs. - moving counters ahead and behind pending timers. - having the same timer condition firing multiple times. The tests run while checking the state of the IRQs (e.g., pending when they are supposed to be) and stressing things a bit by waiting for interrupts while: re-scheduling the vcpu (with sched_yield()), by migrating the vcpu between cores, or by sleeping in userspace (with usleep()). The first commit adds a timer utility function. The second commit adds some sanity checks and basic tests for the timer. The third commit adds the actual edge case tests (like forcing rollovers). v3 ->v4: - Fix is_cpu_online to also check whether the cpu is allowed to run the current process (on top of being online). Renamed is_cpu_online() to is_cpu_eligible_to_run(). [Sean] v2 -> v3: https://lore.kernel.org/kvmarm/20220322172319.2943101-1-ricarkol@xxxxxxxxxx/ - Add missing isb when polling for IRQ being handled. [Oliver, Marc] - Wait for a counter pass by polling on it (instead of the previous isb). [Oliver, Marc] - Edits in some comments. [Oliver] - Dropping the msecs_to_usecs macro. [Oliver] - Skipping test if desired pcpus are not online. This needed adding a library function (is_cpu_online). [Oliver] v1 -> v2: https://lore.kernel.org/kvmarm/20220317045127.124602-1-ricarkol@xxxxxxxxxx/ - Remove the checks for timers firing within some margin; only leave the checks for timers not firing ahead of time. Also remove the tests that depend on timers firing within some margin. [Oliver, Marc] - Collect R-b tag from Oliver (first commit). [Oliver] - Multiple nits: replace wfi_ functions with wait_, reduce use of macros, drop typedefs, use IAR_SPURIOUS from header, move some comments functions to top. [Oliver] - Don't fail if the test has a single cpu available. [Oliver] - Don't fail if there's no GICv3 available. [Oliver] v1: https://lore.kernel.org/kvmarm/20220302172144.2734258-1-ricarkol@xxxxxxxxxx/ Ricardo Koller (4): KVM: arm64: selftests: add timer_get_tval() lib function KVM: selftests: add is_cpu_eligible_to_run() utility function KVM: arm64: selftests: add arch_timer_edge_cases KVM: arm64: selftests: add edge cases tests into arch_timer_edge_cases tools/testing/selftests/kvm/.gitignore | 1 + tools/testing/selftests/kvm/Makefile | 1 + .../kvm/aarch64/arch_timer_edge_cases.c | 904 ++++++++++++++++++ .../kvm/include/aarch64/arch_timer.h | 18 +- .../testing/selftests/kvm/include/test_util.h | 2 + tools/testing/selftests/kvm/lib/test_util.c | 20 +- 6 files changed, 944 insertions(+), 2 deletions(-) create mode 100644 tools/testing/selftests/kvm/aarch64/arch_timer_edge_cases.c -- 2.35.1.1094.g7c7d902a7c-goog
