diff options
Diffstat (limited to 'tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/preempt.c')
-rw-r--r-- | tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/preempt.c | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/preempt.c b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/preempt.c new file mode 100644 index 000000000000..4f1b068e9b7a --- /dev/null +++ b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/preempt.c @@ -0,0 +1,78 @@ +#include <config.h> + +#include "preempt.h" + +#include "assume.h" +#include "locks.h" + +/* Support NR_CPUS of at most 64 */ +#define CPU_PREEMPTION_LOCKS_INIT0 LOCK_IMPL_INITIALIZER +#define CPU_PREEMPTION_LOCKS_INIT1 \ + CPU_PREEMPTION_LOCKS_INIT0, CPU_PREEMPTION_LOCKS_INIT0 +#define CPU_PREEMPTION_LOCKS_INIT2 \ + CPU_PREEMPTION_LOCKS_INIT1, CPU_PREEMPTION_LOCKS_INIT1 +#define CPU_PREEMPTION_LOCKS_INIT3 \ + CPU_PREEMPTION_LOCKS_INIT2, CPU_PREEMPTION_LOCKS_INIT2 +#define CPU_PREEMPTION_LOCKS_INIT4 \ + CPU_PREEMPTION_LOCKS_INIT3, CPU_PREEMPTION_LOCKS_INIT3 +#define CPU_PREEMPTION_LOCKS_INIT5 \ + CPU_PREEMPTION_LOCKS_INIT4, CPU_PREEMPTION_LOCKS_INIT4 + +/* + * Simulate disabling preemption by locking a particular cpu. NR_CPUS + * should be the actual number of cpus, not just the maximum. + */ +struct lock_impl cpu_preemption_locks[NR_CPUS] = { + CPU_PREEMPTION_LOCKS_INIT0 +#if (NR_CPUS - 1) & 1 + , CPU_PREEMPTION_LOCKS_INIT0 +#endif +#if (NR_CPUS - 1) & 2 + , CPU_PREEMPTION_LOCKS_INIT1 +#endif +#if (NR_CPUS - 1) & 4 + , CPU_PREEMPTION_LOCKS_INIT2 +#endif +#if (NR_CPUS - 1) & 8 + , CPU_PREEMPTION_LOCKS_INIT3 +#endif +#if (NR_CPUS - 1) & 16 + , CPU_PREEMPTION_LOCKS_INIT4 +#endif +#if (NR_CPUS - 1) & 32 + , CPU_PREEMPTION_LOCKS_INIT5 +#endif +}; + +#undef CPU_PREEMPTION_LOCKS_INIT0 +#undef CPU_PREEMPTION_LOCKS_INIT1 +#undef CPU_PREEMPTION_LOCKS_INIT2 +#undef CPU_PREEMPTION_LOCKS_INIT3 +#undef CPU_PREEMPTION_LOCKS_INIT4 +#undef CPU_PREEMPTION_LOCKS_INIT5 + +__thread int thread_cpu_id; +__thread int preempt_disable_count; + +void preempt_disable(void) +{ + BUG_ON(preempt_disable_count < 0 || preempt_disable_count == INT_MAX); + + if (preempt_disable_count++) + return; + + thread_cpu_id = nondet_int(); + assume(thread_cpu_id >= 0); + assume(thread_cpu_id < NR_CPUS); + lock_impl_lock(&cpu_preemption_locks[thread_cpu_id]); +} + +void preempt_enable(void) +{ + BUG_ON(preempt_disable_count < 1); + + if (--preempt_disable_count) + return; + + lock_impl_unlock(&cpu_preemption_locks[thread_cpu_id]); +} |