Pull perf/kprobes updates from Thomas Gleixner:
 "Make kretprobes lockless to avoid the rp->lock performance and
  potential lock ordering issues"

* tag 'perf-kprobes-2020-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/atomics: Regenerate the atomics-check SHA1's
  kprobes: Replace rp->free_instance with freelist
  freelist: Implement lockless freelist
  asm-generic/atomic: Add try_cmpxchg() fallbacks
  kprobes: Remove kretprobe hash
  llist: Add nonatomic __llist_add() and __llist_dell_all()