From: Paul E. McKenney Date: Tue, 29 May 2012 06:57:46 +0000 (-0700) Subject: rcu: Move _rcu_barrier()'s rcu_head structures to rcu_data structures X-Git-Tag: upstream/snapshot3+hdmi~7040^2^2~14 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=06668efa9180f4824fe846a8ff96338c18646bc7;p=platform%2Fadaptation%2Frenesas_rcar%2Frenesas_kernel.git rcu: Move _rcu_barrier()'s rcu_head structures to rcu_data structures In order for multiple flavors of RCU to each concurrently run one rcu_barrier(), each flavor needs its own per-CPU set of rcu_head structures. This commit therefore moves _rcu_barrier()'s set of per-CPU rcu_head structures from per-CPU variables to the existing per-CPU and per-RCU-flavor rcu_data structures. Signed-off-by: Paul E. McKenney Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- diff --git a/kernel/rcutree.c b/kernel/rcutree.c index 00c518f..1e55259 100644 --- a/kernel/rcutree.c +++ b/kernel/rcutree.c @@ -157,7 +157,6 @@ unsigned long rcutorture_vernum; /* State information for rcu_barrier() and friends. */ -static DEFINE_PER_CPU(struct rcu_head, rcu_barrier_head) = {NULL}; static atomic_t rcu_barrier_cpu_count; static DEFINE_MUTEX(rcu_barrier_mutex); static struct completion rcu_barrier_completion; @@ -2282,12 +2281,11 @@ static void rcu_barrier_callback(struct rcu_head *notused) */ static void rcu_barrier_func(void *type) { - int cpu = smp_processor_id(); - struct rcu_head *head = &per_cpu(rcu_barrier_head, cpu); struct rcu_state *rsp = type; + struct rcu_data *rdp = __this_cpu_ptr(rsp->rda); atomic_inc(&rcu_barrier_cpu_count); - rsp->call(head, rcu_barrier_callback); + rsp->call(&rdp->barrier_head, rcu_barrier_callback); } /* diff --git a/kernel/rcutree.h b/kernel/rcutree.h index 049896a..586d93c 100644 --- a/kernel/rcutree.h +++ b/kernel/rcutree.h @@ -314,6 +314,9 @@ struct rcu_data { unsigned long n_rp_need_fqs; unsigned long n_rp_need_nothing; + /* 6) _rcu_barrier() callback. */ + struct rcu_head barrier_head; + int cpu; struct rcu_state *rsp; };