#ifndef _PERF_PSTACK_#define _PERF_PSTACK_ struct pstack;struct pstack *pstack__new(unsigned short max_nr_entries);void pstack__delete(struct pstack *self);bool pstack__empty(const struct pstack *self);void pstack__remove(struct pstack *self, void *key);void pstack__push(struct pstack *self, void *key);void *pstack__pop(struct pstack *self); #endif /* _PERF_PSTACK_ */