RCU_BH 671 include/linux/rcupdate.h __acquire(RCU_BH); RCU_BH 687 include/linux/rcupdate.h __release(RCU_BH); RCU_BH 2510 net/ipv6/ip6_fib.c __acquires(RCU_BH) RCU_BH 2534 net/ipv6/ip6_fib.c __releases(RCU_BH)