srcu: Remove superfluous sdp->srcu_lock_count zero filling

Because alloc_percpu() zeroes out the allocated memory, there is no need
to zero-fill newly allocated per-CPU memory.  This commit therefore removes
the loop zeroing the ->srcu_lock_count and ->srcu_unlock_count arrays
from init_srcu_struct_nodes().  This is the only use of that function's
is_static parameter, which this commit also removes.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Neeraj Upadhyay <neeraju@codeaurora.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Uladzislau Rezki <urezki@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c
index e26547b34ad33c6b7d075fcd8b0930f036f76804..3414aff2a4b0fc812c94d748649f1d0586bfbdec 100644 (file)
--- a/kernel/rcu/srcutree.c
+++ b/kernel/rcu/srcutree.c
@@ -80,7 +80,7 @@ do {                                                                  \
  * srcu_read_unlock() running against them.  So if the is_static parameter
  * is set, don't initialize ->srcu_lock_count[] and ->srcu_unlock_count[].
  */
-static void init_srcu_struct_nodes(struct srcu_struct *ssp, bool is_static)
+static void init_srcu_struct_nodes(struct srcu_struct *ssp)
 {
        int cpu;
        int i;
@@ -148,14 +148,6 @@ static void init_srcu_struct_nodes(struct srcu_struct *ssp, bool is_static)
                timer_setup(&sdp->delay_work, srcu_delay_timer, 0);
                sdp->ssp = ssp;
                sdp->grpmask = 1 << (cpu - sdp->mynode->grplo);
-               if (is_static)
-                       continue;
-
-               /* Dynamically allocated, better be no srcu_read_locks()! */
-               for (i = 0; i < ARRAY_SIZE(sdp->srcu_lock_count); i++) {
-                       sdp->srcu_lock_count[i] = 0;
-                       sdp->srcu_unlock_count[i] = 0;
-               }
        }
 }
 
@@ -179,7 +171,7 @@ static int init_srcu_struct_fields(struct srcu_struct *ssp, bool is_static)
                ssp->sda = alloc_percpu(struct srcu_data);
        if (!ssp->sda)
                return -ENOMEM;
-       init_srcu_struct_nodes(ssp, is_static);
+       init_srcu_struct_nodes(ssp);
        ssp->srcu_gp_seq_needed_exp = 0;
        ssp->srcu_last_gp_end = ktime_get_mono_fast_ns();
        smp_store_release(&ssp->srcu_gp_seq_needed, 0); /* Init done. */