* kprobes, tracepoints) to prevent deadlocks on map operations as any of
* these events can happen inside a region which holds a map bucket lock
* and can deadlock on it.
- *
- * Use the preemption safe inc/dec variants on RT because migrate disable
- * is preemptible on RT and preemption in the middle of the RMW operation
- * might lead to inconsistent state. Use the raw variants for non RT
- * kernels as migrate_disable() maps to preempt_disable() so the slightly
- * more expensive save operation can be avoided.
*/
static inline void bpf_disable_instrumentation(void)
{
migrate_disable();
- if (IS_ENABLED(CONFIG_PREEMPT_RT))
- this_cpu_inc(bpf_prog_active);
- else
- __this_cpu_inc(bpf_prog_active);
+ this_cpu_inc(bpf_prog_active);
}
static inline void bpf_enable_instrumentation(void)
{
- if (IS_ENABLED(CONFIG_PREEMPT_RT))
- this_cpu_dec(bpf_prog_active);
- else
- __this_cpu_dec(bpf_prog_active);
+ this_cpu_dec(bpf_prog_active);
migrate_enable();
}
* This uses migrate_disable/enable() explicitly to document that the
* invocation of a BPF program does not require reentrancy protection
* against a BPF program which is invoked from a preempting task.
- *
- * For non RT enabled kernels migrate_disable/enable() maps to
- * preempt_disable/enable(), i.e. it disables also preemption.
*/
static inline u32 bpf_prog_run_pin_on_cpu(const struct bpf_prog *prog,
const void *ctx)