From: Paul E. McKenney Date: Fri, 16 Jan 2015 22:01:21 +0000 (-0800) Subject: rcu: Consolidate offline-CPU callback initialization X-Git-Tag: v4.1-rc1~145^2~2^2^5~17 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=b33078b6098148c3efdacc907249a247c9d5491e;p=karo-tx-linux.git rcu: Consolidate offline-CPU callback initialization Currently, both rcu_cleanup_dead_cpu() and rcu_send_cbs_to_orphanage() initialize the outgoing CPU's callback list. However, only rcu_cleanup_dead_cpu() invokes rcu_send_cbs_to_orphanage(), and it does so unconditionally, which means that only one of these initializations is required. This commit therefore consolidates the callback-list initialization with the rest of the callback handling in rcu_send_cbs_to_orphanage(). Signed-off-by: Paul E. McKenney --- diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 48d640ca1a05..8e020c59ecfd 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -2256,8 +2256,12 @@ rcu_send_cbs_to_orphanage(int cpu, struct rcu_state *rsp, rsp->orphan_donetail = rdp->nxttail[RCU_DONE_TAIL]; } - /* Finally, initialize the rcu_data structure's list to empty. */ + /* + * Finally, initialize the rcu_data structure's list to empty and + * disallow further callbacks on this CPU. + */ init_callback_list(rdp); + rdp->nxttail[RCU_NEXT_TAIL] = NULL; } /* @@ -2398,9 +2402,6 @@ static void rcu_cleanup_dead_cpu(int cpu, struct rcu_state *rsp) WARN_ONCE(rdp->qlen != 0 || rdp->nxtlist != NULL, "rcu_cleanup_dead_cpu: Callbacks on offline CPU %d: qlen=%lu, nxtlist=%p\n", cpu, rdp->qlen, rdp->nxtlist); - init_callback_list(rdp); - /* Disallow further callbacks on this CPU. */ - rdp->nxttail[RCU_NEXT_TAIL] = NULL; mutex_unlock(&rsp->onoff_mutex); }