filter_event
static bool is_filter_entry_match(u64 filter_event, u64 umask)
u64 mask = filter_event >> (KVM_PMU_MASKED_ENTRY_UMASK_MASK_SHIFT - 8);
u64 match = filter_event & KVM_PMU_MASKED_ENTRY_UMASK_MATCH;
int filter_event(void *data, const struct perf_dlfilter_sample *sample, void *ctx);
d->filter_event = dlsym(d->handle, "filter_event");
ret = d->filter_event(d->data, &d_sample, d);
int (*filter_event)(void *data,
if (!d || !d->filter_event)