rcu: Convert ACCESS_ONCE() to READ_ONCE() and WRITE_ONCE()

This commit moves from the old ACCESS_ONCE() API to the new READ_ONCE()
and WRITE_ONCE() APIs.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck:  Updated to include kernel/torture.c as suggested by Jason Low. ]

7 files changed, 169 insertions, 168 deletions

diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 8dbe27611ec3..a67ef6ff86b0 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -1413,7 +1413,7 @@ static int rcu_torture_barrier_cbs(void *arg)
         do {
                 wait_event(barrier_cbs_wq[myid],
                            (newphase =
-                            ACCESS_ONCE(barrier_phase)) != lastphase ||
+                            READ_ONCE(barrier_phase)) != lastphase ||
                            torture_must_stop());
                 lastphase = newphase;
                 smp_mb(); /* ensure barrier_phase load before ->call(). */
diff --git a/kernel/rcu/srcu.c b/kernel/rcu/srcu.c
index cad76e76b4e7..fb33d35ee0b7 100644
--- a/kernel/rcu/srcu.c
+++ b/kernel/rcu/srcu.c
@@ -151,7 +151,7 @@ static unsigned long srcu_readers_seq_idx(struct srcu_struct *sp, int idx)
         unsigned long t;
 
         for_each_possible_cpu(cpu) {
-                t = ACCESS_ONCE(per_cpu_ptr(sp->per_cpu_ref, cpu)->seq[idx]);
+                t = READ_ONCE(per_cpu_ptr(sp->per_cpu_ref, cpu)->seq[idx]);
                 sum += t;
         }
         return sum;
@@ -168,7 +168,7 @@ static unsigned long srcu_readers_active_idx(struct srcu_struct *sp, int idx)
         unsigned long t;
 
         for_each_possible_cpu(cpu) {
-                t = ACCESS_ONCE(per_cpu_ptr(sp->per_cpu_ref, cpu)->c[idx]);
+                t = READ_ONCE(per_cpu_ptr(sp->per_cpu_ref, cpu)->c[idx]);
                 sum += t;
         }
         return sum;
@@ -265,8 +265,8 @@ static int srcu_readers_active(struct srcu_struct *sp)
         unsigned long sum = 0;
 
         for_each_possible_cpu(cpu) {
-                sum += ACCESS_ONCE(per_cpu_ptr(sp->per_cpu_ref, cpu)->c[0]);
-                sum += ACCESS_ONCE(per_cpu_ptr(sp->per_cpu_ref, cpu)->c[1]);
+                sum += READ_ONCE(per_cpu_ptr(sp->per_cpu_ref, cpu)->c[0]);
+                sum += READ_ONCE(per_cpu_ptr(sp->per_cpu_ref, cpu)->c[1]);
         }
         return sum;
 }
@@ -296,7 +296,7 @@ int __srcu_read_lock(struct srcu_struct *sp)
 {
         int idx;
 
-        idx = ACCESS_ONCE(sp->completed) & 0x1;
+        idx = READ_ONCE(sp->completed) & 0x1;
         preempt_disable();
         __this_cpu_inc(sp->per_cpu_ref->c[idx]);
         smp_mb(); /* B */  /* Avoid leaking the critical section. */
diff --git a/kernel/rcu/tiny_plugin.h b/kernel/rcu/tiny_plugin.h
index f94e209a10d6..e492a5253e0f 100644
--- a/kernel/rcu/tiny_plugin.h
+++ b/kernel/rcu/tiny_plugin.h
@@ -144,16 +144,17 @@ static void check_cpu_stall(struct rcu_ctrlblk *rcp)
                 return;
         rcp->ticks_this_gp++;
         j = jiffies;
-        js = ACCESS_ONCE(rcp->jiffies_stall);
+        js = READ_ONCE(rcp->jiffies_stall);
         if (rcp->rcucblist && ULONG_CMP_GE(j, js)) {
                 pr_err("INFO: %s stall on CPU (%lu ticks this GP) idle=%llx (t=%lu jiffies q=%ld)\n",
                        rcp->name, rcp->ticks_this_gp, DYNTICK_TASK_EXIT_IDLE,
                        jiffies - rcp->gp_start, rcp->qlen);
                 dump_stack();
-                ACCESS_ONCE(rcp->jiffies_stall) = jiffies +
-                        3 * rcu_jiffies_till_stall_check() + 3;
+                WRITE_ONCE(rcp->jiffies_stall,
+                           jiffies + 3 * rcu_jiffies_till_stall_check() + 3);
         } else if (ULONG_CMP_GE(j, js)) {
-                ACCESS_ONCE(rcp->jiffies_stall) = jiffies + rcu_jiffies_till_stall_check();
+                WRITE_ONCE(rcp->jiffies_stall,
+                           jiffies + rcu_jiffies_till_stall_check());
         }
 }
 
@@ -161,7 +162,8 @@ static void reset_cpu_stall_ticks(struct rcu_ctrlblk *rcp)
 {
         rcp->ticks_this_gp = 0;
         rcp->gp_start = jiffies;
-        ACCESS_ONCE(rcp->jiffies_stall) = jiffies + rcu_jiffies_till_stall_check();
+        WRITE_ONCE(rcp->jiffies_stall,
+                   jiffies + rcu_jiffies_till_stall_check());
 }
 
 static void check_cpu_stalls(void)
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 8cf7304b2867..0628df155970 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -191,17 +191,17 @@ unsigned long rcutorture_vernum;
  */
 unsigned long rcu_rnp_online_cpus(struct rcu_node *rnp)
 {
-        return ACCESS_ONCE(rnp->qsmaskinitnext);
+        return READ_ONCE(rnp->qsmaskinitnext);
 }
 
 /*
- * Return true if an RCU grace period is in progress.  The ACCESS_ONCE()s
+ * Return true if an RCU grace period is in progress.  The READ_ONCE()s
  * permit this function to be invoked without holding the root rcu_node
  * structure's ->lock, but of course results can be subject to change.
  */
 static int rcu_gp_in_progress(struct rcu_state *rsp)
 {
-        return ACCESS_ONCE(rsp->completed) != ACCESS_ONCE(rsp->gpnum);
+        return READ_ONCE(rsp->completed) != READ_ONCE(rsp->gpnum);
 }
 
 /*
@@ -278,8 +278,8 @@ static void rcu_momentary_dyntick_idle(void)
                 if (!(resched_mask & rsp->flavor_mask))
                         continue;
                 smp_mb(); /* rcu_sched_qs_mask before cond_resched_completed. */
-                if (ACCESS_ONCE(rdp->mynode->completed) !=
-                    ACCESS_ONCE(rdp->cond_resched_completed))
+                if (READ_ONCE(rdp->mynode->completed) !=
+                    READ_ONCE(rdp->cond_resched_completed))
                         continue;
 
                 /*
@@ -491,9 +491,9 @@ void rcutorture_get_gp_data(enum rcutorture_type test_type, int *flags,
                 break;
         }
         if (rsp != NULL) {
-                *flags = ACCESS_ONCE(rsp->gp_flags);
-                *gpnum = ACCESS_ONCE(rsp->gpnum);
-                *completed = ACCESS_ONCE(rsp->completed);
+                *flags = READ_ONCE(rsp->gp_flags);
+                *gpnum = READ_ONCE(rsp->gpnum);
+                *completed = READ_ONCE(rsp->completed);
                 return;
         }
         *flags = 0;
@@ -539,10 +539,10 @@ static struct rcu_node *rcu_get_root(struct rcu_state *rsp)
 static int rcu_future_needs_gp(struct rcu_state *rsp)
 {
         struct rcu_node *rnp = rcu_get_root(rsp);
-        int idx = (ACCESS_ONCE(rnp->completed) + 1) & 0x1;
+        int idx = (READ_ONCE(rnp->completed) + 1) & 0x1;
         int *fp = &rnp->need_future_gp[idx];
 
-        return ACCESS_ONCE(*fp);
+        return READ_ONCE(*fp);
 }
 
 /*
@@ -565,7 +565,7 @@ cpu_needs_another_gp(struct rcu_state *rsp, struct rcu_data *rdp)
                 return 1;  /* Yes, this CPU has newly registered callbacks. */
         for (i = RCU_WAIT_TAIL; i < RCU_NEXT_TAIL; i++)
                 if (rdp->nxttail[i - 1] != rdp->nxttail[i] &&
-                    ULONG_CMP_LT(ACCESS_ONCE(rsp->completed),
+                    ULONG_CMP_LT(READ_ONCE(rsp->completed),
                                  rdp->nxtcompleted[i]))
                         return 1;  /* Yes, CBs for future grace period. */
         return 0; /* No grace period needed. */
@@ -1011,9 +1011,9 @@ static int dyntick_save_progress_counter(struct rcu_data *rdp,
                 trace_rcu_fqs(rdp->rsp->name, rdp->gpnum, rdp->cpu, TPS("dti"));
                 return 1;
         } else {
-                if (ULONG_CMP_LT(ACCESS_ONCE(rdp->gpnum) + ULONG_MAX / 4,
+                if (ULONG_CMP_LT(READ_ONCE(rdp->gpnum) + ULONG_MAX / 4,
                                  rdp->mynode->gpnum))
-                        ACCESS_ONCE(rdp->gpwrap) = true;
+                        WRITE_ONCE(rdp->gpwrap, true);
                 return 0;
         }
 }
@@ -1093,12 +1093,12 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp,
         if (ULONG_CMP_GE(jiffies,
                          rdp->rsp->gp_start + jiffies_till_sched_qs) ||
             ULONG_CMP_GE(jiffies, rdp->rsp->jiffies_resched)) {
-                if (!(ACCESS_ONCE(*rcrmp) & rdp->rsp->flavor_mask)) {
-                        ACCESS_ONCE(rdp->cond_resched_completed) =
-                                ACCESS_ONCE(rdp->mynode->completed);
+                if (!(READ_ONCE(*rcrmp) & rdp->rsp->flavor_mask)) {
+                        WRITE_ONCE(rdp->cond_resched_completed,
+                                   READ_ONCE(rdp->mynode->completed));
                         smp_mb(); /* ->cond_resched_completed before *rcrmp. */
-                        ACCESS_ONCE(*rcrmp) =
-                                ACCESS_ONCE(*rcrmp) + rdp->rsp->flavor_mask;
+                        WRITE_ONCE(*rcrmp,
+                                   READ_ONCE(*rcrmp) + rdp->rsp->flavor_mask);
                         resched_cpu(rdp->cpu);  /* Force CPU into scheduler. */
                         rdp->rsp->jiffies_resched += 5; /* Enable beating. */
                 } else if (ULONG_CMP_GE(jiffies, rdp->rsp->jiffies_resched)) {
@@ -1119,9 +1119,9 @@ static void record_gp_stall_check_time(struct rcu_state *rsp)
         rsp->gp_start = j;
         smp_wmb(); /* Record start time before stall time. */
         j1 = rcu_jiffies_till_stall_check();
-        ACCESS_ONCE(rsp->jiffies_stall) = j + j1;
+        WRITE_ONCE(rsp->jiffies_stall, j + j1);
         rsp->jiffies_resched = j + j1 / 2;
-        rsp->n_force_qs_gpstart = ACCESS_ONCE(rsp->n_force_qs);
+        rsp->n_force_qs_gpstart = READ_ONCE(rsp->n_force_qs);
 }
 
 /*
@@ -1133,7 +1133,7 @@ static void rcu_check_gp_kthread_starvation(struct rcu_state *rsp)
         unsigned long j;
 
         j = jiffies;
-        gpa = ACCESS_ONCE(rsp->gp_activity);
+        gpa = READ_ONCE(rsp->gp_activity);
         if (j - gpa > 2 * HZ)
                 pr_err("%s kthread starved for %ld jiffies!\n",
                        rsp->name, j - gpa);
@@ -1173,12 +1173,13 @@ static void print_other_cpu_stall(struct rcu_state *rsp, unsigned long gpnum)
         /* Only let one CPU complain about others per time interval. */
 
         raw_spin_lock_irqsave(&rnp->lock, flags);
-        delta = jiffies - ACCESS_ONCE(rsp->jiffies_stall);
+        delta = jiffies - READ_ONCE(rsp->jiffies_stall);
         if (delta < RCU_STALL_RAT_DELAY || !rcu_gp_in_progress(rsp)) {
                 raw_spin_unlock_irqrestore(&rnp->lock, flags);
                 return;
         }
-        ACCESS_ONCE(rsp->jiffies_stall) = jiffies + 3 * rcu_jiffies_till_stall_check() + 3;
+        WRITE_ONCE(rsp->jiffies_stall,
+                   jiffies + 3 * rcu_jiffies_till_stall_check() + 3);
         raw_spin_unlock_irqrestore(&rnp->lock, flags);
 
         /*
@@ -1212,12 +1213,12 @@ static void print_other_cpu_stall(struct rcu_state *rsp, unsigned long gpnum)
         if (ndetected) {
                 rcu_dump_cpu_stacks(rsp);
         } else {
-                if (ACCESS_ONCE(rsp->gpnum) != gpnum ||
-                    ACCESS_ONCE(rsp->completed) == gpnum) {
+                if (READ_ONCE(rsp->gpnum) != gpnum ||
+                    READ_ONCE(rsp->completed) == gpnum) {
                         pr_err("INFO: Stall ended before state dump start\n");
                 } else {
                         j = jiffies;
-                        gpa = ACCESS_ONCE(rsp->gp_activity);
+                        gpa = READ_ONCE(rsp->gp_activity);
                         pr_err("All QSes seen, last %s kthread activity %ld (%ld-%ld), jiffies_till_next_fqs=%ld, root ->qsmask %#lx\n",
                                rsp->name, j - gpa, j, gpa,
                                jiffies_till_next_fqs,
@@ -1262,9 +1263,9 @@ static void print_cpu_stall(struct rcu_state *rsp)
         rcu_dump_cpu_stacks(rsp);
 
         raw_spin_lock_irqsave(&rnp->lock, flags);
-        if (ULONG_CMP_GE(jiffies, ACCESS_ONCE(rsp->jiffies_stall)))
-                ACCESS_ONCE(rsp->jiffies_stall) = jiffies +
-                                     3 * rcu_jiffies_till_stall_check() + 3;
+        if (ULONG_CMP_GE(jiffies, READ_ONCE(rsp->jiffies_stall)))
+                WRITE_ONCE(rsp->jiffies_stall,
+                           jiffies + 3 * rcu_jiffies_till_stall_check() + 3);
         raw_spin_unlock_irqrestore(&rnp->lock, flags);
 
         /*
@@ -1307,20 +1308,20 @@ static void check_cpu_stall(struct rcu_state *rsp, struct rcu_data *rdp)
          * Given this check, comparisons of jiffies, rsp->jiffies_stall,
          * and rsp->gp_start suffice to forestall false positives.
          */
-        gpnum = ACCESS_ONCE(rsp->gpnum);
+        gpnum = READ_ONCE(rsp->gpnum);
         smp_rmb(); /* Pick up ->gpnum first... */
-        js = ACCESS_ONCE(rsp->jiffies_stall);
+        js = READ_ONCE(rsp->jiffies_stall);
         smp_rmb(); /* ...then ->jiffies_stall before the rest... */
-        gps = ACCESS_ONCE(rsp->gp_start);
+        gps = READ_ONCE(rsp->gp_start);
         smp_rmb(); /* ...and finally ->gp_start before ->completed. */
-        completed = ACCESS_ONCE(rsp->completed);
+        completed = READ_ONCE(rsp->completed);
         if (ULONG_CMP_GE(completed, gpnum) ||
             ULONG_CMP_LT(j, js) ||
             ULONG_CMP_GE(gps, js))
                 return; /* No stall or GP completed since entering function. */
         rnp = rdp->mynode;
         if (rcu_gp_in_progress(rsp) &&
-            (ACCESS_ONCE(rnp->qsmask) & rdp->grpmask)) {
+            (READ_ONCE(rnp->qsmask) & rdp->grpmask)) {
 
                 /* We haven't checked in, so go dump stack. */
                 print_cpu_stall(rsp);
@@ -1347,7 +1348,7 @@ void rcu_cpu_stall_reset(void)
         struct rcu_state *rsp;
 
         for_each_rcu_flavor(rsp)
-                ACCESS_ONCE(rsp->jiffies_stall) = jiffies + ULONG_MAX / 2;
+                WRITE_ONCE(rsp->jiffies_stall, jiffies + ULONG_MAX / 2);
 }
 
 /*
@@ -1457,7 +1458,7 @@ rcu_start_future_gp(struct rcu_node *rnp, struct rcu_data *rdp,
          * doing some extra useless work.
          */
         if (rnp->gpnum != rnp->completed ||
-            ACCESS_ONCE(rnp_root->gpnum) != ACCESS_ONCE(rnp_root->completed)) {
+            READ_ONCE(rnp_root->gpnum) != READ_ONCE(rnp_root->completed)) {
                 rnp->need_future_gp[c & 0x1]++;
                 trace_rcu_future_gp(rnp, rdp, c, TPS("Startedleaf"));
                 goto out;
@@ -1542,7 +1543,7 @@ static int rcu_future_gp_cleanup(struct rcu_state *rsp, struct rcu_node *rnp)
 static void rcu_gp_kthread_wake(struct rcu_state *rsp)
 {
         if (current == rsp->gp_kthread ||
-            !ACCESS_ONCE(rsp->gp_flags) ||
+            !READ_ONCE(rsp->gp_flags) ||
             !rsp->gp_kthread)
                 return;
         wake_up(&rsp->gp_wq);
@@ -1677,7 +1678,7 @@ static bool __note_gp_changes(struct rcu_state *rsp, struct rcu_node *rnp,
 
         /* Handle the ends of any preceding grace periods first. */
         if (rdp->completed == rnp->completed &&
-            !unlikely(ACCESS_ONCE(rdp->gpwrap))) {
+            !unlikely(READ_ONCE(rdp->gpwrap))) {
 
                 /* No grace period end, so just accelerate recent callbacks. */
                 ret = rcu_accelerate_cbs(rsp, rnp, rdp);
@@ -1692,7 +1693,7 @@ static bool __note_gp_changes(struct rcu_state *rsp, struct rcu_node *rnp,
                 trace_rcu_grace_period(rsp->name, rdp->gpnum, TPS("cpuend"));
         }
 
-        if (rdp->gpnum != rnp->gpnum || unlikely(ACCESS_ONCE(rdp->gpwrap))) {
+        if (rdp->gpnum != rnp->gpnum || unlikely(READ_ONCE(rdp->gpwrap))) {
                 /*
                  * If the current grace period is waiting for this CPU,
                  * set up to detect a quiescent state, otherwise don't
@@ -1704,7 +1705,7 @@ static bool __note_gp_changes(struct rcu_state *rsp, struct rcu_node *rnp,
                 rdp->rcu_qs_ctr_snap = __this_cpu_read(rcu_qs_ctr);
                 rdp->qs_pending = !!(rnp->qsmask & rdp->grpmask);
                 zero_cpu_stall_ticks(rdp);
-                ACCESS_ONCE(rdp->gpwrap) = false;
+                WRITE_ONCE(rdp->gpwrap, false);
         }
         return ret;
 }
@@ -1717,9 +1718,9 @@ static void note_gp_changes(struct rcu_state *rsp, struct rcu_data *rdp)
 
         local_irq_save(flags);
         rnp = rdp->mynode;
-        if ((rdp->gpnum == ACCESS_ONCE(rnp->gpnum) &&
-             rdp->completed == ACCESS_ONCE(rnp->completed) &&
-             !unlikely(ACCESS_ONCE(rdp->gpwrap))) || /* w/out lock. */
+        if ((rdp->gpnum == READ_ONCE(rnp->gpnum) &&
+             rdp->completed == READ_ONCE(rnp->completed) &&
+             !unlikely(READ_ONCE(rdp->gpwrap))) || /* w/out lock. */
             !raw_spin_trylock(&rnp->lock)) { /* irqs already off, so later. */
                 local_irq_restore(flags);
                 return;
@@ -1740,15 +1741,15 @@ static int rcu_gp_init(struct rcu_state *rsp)
         struct rcu_data *rdp;
         struct rcu_node *rnp = rcu_get_root(rsp);
 
-        ACCESS_ONCE(rsp->gp_activity) = jiffies;
+        WRITE_ONCE(rsp->gp_activity, jiffies);
         raw_spin_lock_irq(&rnp->lock);
         smp_mb__after_unlock_lock();
-        if (!ACCESS_ONCE(rsp->gp_flags)) {
+        if (!READ_ONCE(rsp->gp_flags)) {
                 /* Spurious wakeup, tell caller to go back to sleep.  */
                 raw_spin_unlock_irq(&rnp->lock);
                 return 0;
         }
-        ACCESS_ONCE(rsp->gp_flags) = 0; /* Clear all flags: New grace period. */
+        WRITE_ONCE(rsp->gp_flags, 0); /* Clear all flags: New grace period. */
 
         if (WARN_ON_ONCE(rcu_gp_in_progress(rsp))) {
                 /*
@@ -1834,9 +1835,9 @@ static int rcu_gp_init(struct rcu_state *rsp)
                 rdp = this_cpu_ptr(rsp->rda);
                 rcu_preempt_check_blocked_tasks(rnp);
                 rnp->qsmask = rnp->qsmaskinit;
-                ACCESS_ONCE(rnp->gpnum) = rsp->gpnum;
+                WRITE_ONCE(rnp->gpnum, rsp->gpnum);
                 if (WARN_ON_ONCE(rnp->completed != rsp->completed))
-                        ACCESS_ONCE(rnp->completed) = rsp->completed;
+                        WRITE_ONCE(rnp->completed, rsp->completed);
                 if (rnp == rdp->mynode)
                         (void)__note_gp_changes(rsp, rnp, rdp);
                 rcu_preempt_boost_start_gp(rnp);
@@ -1845,7 +1846,7 @@ static int rcu_gp_init(struct rcu_state *rsp)
                                             rnp->grphi, rnp->qsmask);
                 raw_spin_unlock_irq(&rnp->lock);
                 cond_resched_rcu_qs();
-                ACCESS_ONCE(rsp->gp_activity) = jiffies;
+                WRITE_ONCE(rsp->gp_activity, jiffies);
                 if (gp_init_delay > 0 &&
                     !(rsp->gpnum % (rcu_num_nodes * PER_RCU_NODE_PERIOD)))
                         schedule_timeout_uninterruptible(gp_init_delay);
@@ -1864,7 +1865,7 @@ static int rcu_gp_fqs(struct rcu_state *rsp, int fqs_state_in)
         unsigned long maxj;
         struct rcu_node *rnp = rcu_get_root(rsp);
 
-        ACCESS_ONCE(rsp->gp_activity) = jiffies;
+        WRITE_ONCE(rsp->gp_activity, jiffies);
         rsp->n_force_qs++;
         if (fqs_state == RCU_SAVE_DYNTICK) {
                 /* Collect dyntick-idle snapshots. */
@@ -1882,11 +1883,11 @@ static int rcu_gp_fqs(struct rcu_state *rsp, int fqs_state_in)
                 force_qs_rnp(rsp, rcu_implicit_dynticks_qs, &isidle, &maxj);
         }
         /* Clear flag to prevent immediate re-entry. */
-        if (ACCESS_ONCE(rsp->gp_flags) & RCU_GP_FLAG_FQS) {
+        if (READ_ONCE(rsp->gp_flags) & RCU_GP_FLAG_FQS) {
                 raw_spin_lock_irq(&rnp->lock);
                 smp_mb__after_unlock_lock();
-                ACCESS_ONCE(rsp->gp_flags) =
-                        ACCESS_ONCE(rsp->gp_flags) & ~RCU_GP_FLAG_FQS;
+                WRITE_ONCE(rsp->gp_flags,
+                           READ_ONCE(rsp->gp_flags) & ~RCU_GP_FLAG_FQS);
                 raw_spin_unlock_irq(&rnp->lock);
         }
         return fqs_state;
@@ -1903,7 +1904,7 @@ static void rcu_gp_cleanup(struct rcu_state *rsp)
         struct rcu_data *rdp;
         struct rcu_node *rnp = rcu_get_root(rsp);
 
-        ACCESS_ONCE(rsp->gp_activity) = jiffies;
+        WRITE_ONCE(rsp->gp_activity, jiffies);
         raw_spin_lock_irq(&rnp->lock);
         smp_mb__after_unlock_lock();
         gp_duration = jiffies - rsp->gp_start;
@@ -1934,7 +1935,7 @@ static void rcu_gp_cleanup(struct rcu_state *rsp)
                 smp_mb__after_unlock_lock();
                 WARN_ON_ONCE(rcu_preempt_blocked_readers_cgp(rnp));
                 WARN_ON_ONCE(rnp->qsmask);
-                ACCESS_ONCE(rnp->completed) = rsp->gpnum;
+                WRITE_ONCE(rnp->completed, rsp->gpnum);
                 rdp = this_cpu_ptr(rsp->rda);
                 if (rnp == rdp->mynode)
                         needgp = __note_gp_changes(rsp, rnp, rdp) || needgp;
@@ -1942,7 +1943,7 @@ static void rcu_gp_cleanup(struct rcu_state *rsp)
                 nocb += rcu_future_gp_cleanup(rsp, rnp);
                 raw_spin_unlock_irq(&rnp->lock);
                 cond_resched_rcu_qs();
-                ACCESS_ONCE(rsp->gp_activity) = jiffies;
+                WRITE_ONCE(rsp->gp_activity, jiffies);
         }
         rnp = rcu_get_root(rsp);
         raw_spin_lock_irq(&rnp->lock);
@@ -1950,16 +1951,16 @@ static void rcu_gp_cleanup(struct rcu_state *rsp)
         rcu_nocb_gp_set(rnp, nocb);
 
         /* Declare grace period done. */
-        ACCESS_ONCE(rsp->completed) = rsp->gpnum;
+        WRITE_ONCE(rsp->completed, rsp->gpnum);
         trace_rcu_grace_period(rsp->name, rsp->completed, TPS("end"));
         rsp->fqs_state = RCU_GP_IDLE;
         rdp = this_cpu_ptr(rsp->rda);
         /* Advance CBs to reduce false positives below. */
         needgp = rcu_advance_cbs(rsp, rnp, rdp) || needgp;
         if (needgp || cpu_needs_another_gp(rsp, rdp)) {
-                ACCESS_ONCE(rsp->gp_flags) = RCU_GP_FLAG_INIT;
+                WRITE_ONCE(rsp->gp_flags, RCU_GP_FLAG_INIT);
                 trace_rcu_grace_period(rsp->name,
-                                       ACCESS_ONCE(rsp->gpnum),
+                                       READ_ONCE(rsp->gpnum),
                                        TPS("newreq"));
         }
         raw_spin_unlock_irq(&rnp->lock);
@@ -1983,20 +1984,20 @@ static int __noreturn rcu_gp_kthread(void *arg)
                 /* Handle grace-period start. */
                 for (;;) {
                         trace_rcu_grace_period(rsp->name,
-                                               ACCESS_ONCE(rsp->gpnum),
+                                               READ_ONCE(rsp->gpnum),
                                                TPS("reqwait"));
                         rsp->gp_state = RCU_GP_WAIT_GPS;
                         wait_event_interruptible(rsp->gp_wq,
-                                                 ACCESS_ONCE(rsp->gp_flags) &
+                                                 READ_ONCE(rsp->gp_flags) &
                                                  RCU_GP_FLAG_INIT);
                         /* Locking provides needed memory barrier. */
                         if (rcu_gp_init(rsp))
                                 break;
                         cond_resched_rcu_qs();
-                        ACCESS_ONCE(rsp->gp_activity) = jiffies;
+                        WRITE_ONCE(rsp->gp_activity, jiffies);
                         WARN_ON(signal_pending(current));
                         trace_rcu_grace_period(rsp->name,
-                                               ACCESS_ONCE(rsp->gpnum),
+                                               READ_ONCE(rsp->gpnum),
                                                TPS("reqwaitsig"));
                 }
 
@@ -2012,39 +2013,39 @@ static int __noreturn rcu_gp_kthread(void *arg)
                         if (!ret)
                                 rsp->jiffies_force_qs = jiffies + j;
                         trace_rcu_grace_period(rsp->name,
-                                               ACCESS_ONCE(rsp->gpnum),
+                                               READ_ONCE(rsp->gpnum),
                                                TPS("fqswait"));
                         rsp->gp_state = RCU_GP_WAIT_FQS;
                         ret = wait_event_interruptible_timeout(rsp->gp_wq,
-                                        ((gf = ACCESS_ONCE(rsp->gp_flags)) &
+                                        ((gf = READ_ONCE(rsp->gp_flags)) &
                                          RCU_GP_FLAG_FQS) ||
-                                        (!ACCESS_ONCE(rnp->qsmask) &&
+                                        (!READ_ONCE(rnp->qsmask) &&
                                          !rcu_preempt_blocked_readers_cgp(rnp)),
                                         j);
                         /* Locking provides needed memory barriers. */
                         /* If grace period done, leave loop. */
-                        if (!ACCESS_ONCE(rnp->qsmask) &&
+                        if (!READ_ONCE(rnp->qsmask) &&
                             !rcu_preempt_blocked_readers_cgp(rnp))
                                 break;
                         /* If time for quiescent-state forcing, do it. */
                         if (ULONG_CMP_GE(jiffies, rsp->jiffies_force_qs) ||
                             (gf & RCU_GP_FLAG_FQS)) {
                                 trace_rcu_grace_period(rsp->name,
-                                                       ACCESS_ONCE(rsp->gpnum),
+                                                       READ_ONCE(rsp->gpnum),
                                                        TPS("fqsstart"));
                                 fqs_state = rcu_gp_fqs(rsp, fqs_state);
                                 trace_rcu_grace_period(rsp->name,
-                                                       ACCESS_ONCE(rsp->gpnum),
+                                                       READ_ONCE(rsp->gpnum),
                                                        TPS("fqsend"));
                                 cond_resched_rcu_qs();
-                                ACCESS_ONCE(rsp->gp_activity) = jiffies;
+                                WRITE_ONCE(rsp->gp_activity, jiffies);
                         } else {
                                 /* Deal with stray signal. */
                                 cond_resched_rcu_qs();
-                                ACCESS_ONCE(rsp->gp_activity) = jiffies;
+                                WRITE_ONCE(rsp->gp_activity, jiffies);
                                 WARN_ON(signal_pending(current));
                                 trace_rcu_grace_period(rsp->name,
-                                                       ACCESS_ONCE(rsp->gpnum),
+                                                       READ_ONCE(rsp->gpnum),
                                                        TPS("fqswaitsig"));
                         }
                         j = jiffies_till_next_fqs;
@@ -2086,8 +2087,8 @@ rcu_start_gp_advanced(struct rcu_state *rsp, struct rcu_node *rnp,
                  */
                 return false;
         }
-        ACCESS_ONCE(rsp->gp_flags) = RCU_GP_FLAG_INIT;
-        trace_rcu_grace_period(rsp->name, ACCESS_ONCE(rsp->gpnum),
+        WRITE_ONCE(rsp->gp_flags, RCU_GP_FLAG_INIT);
+        trace_rcu_grace_period(rsp->name, READ_ONCE(rsp->gpnum),
                                TPS("newreq"));
 
         /*
@@ -2359,7 +2360,7 @@ rcu_send_cbs_to_orphanage(int cpu, struct rcu_state *rsp,
                 rsp->qlen += rdp->qlen;
                 rdp->n_cbs_orphaned += rdp->qlen;
                 rdp->qlen_lazy = 0;
-                ACCESS_ONCE(rdp->qlen) = 0;
+                WRITE_ONCE(rdp->qlen, 0);
         }
 
         /*
@@ -2580,7 +2581,7 @@ static void rcu_do_batch(struct rcu_state *rsp, struct rcu_data *rdp)
         /* If no callbacks are ready, just return. */
         if (!cpu_has_callbacks_ready_to_invoke(rdp)) {
                 trace_rcu_batch_start(rsp->name, rdp->qlen_lazy, rdp->qlen, 0);
-                trace_rcu_batch_end(rsp->name, 0, !!ACCESS_ONCE(rdp->nxtlist),
+                trace_rcu_batch_end(rsp->name, 0, !!READ_ONCE(rdp->nxtlist),
                                     need_resched(), is_idle_task(current),
                                     rcu_is_callbacks_kthread());
                 return;
@@ -2636,7 +2637,7 @@ static void rcu_do_batch(struct rcu_state *rsp, struct rcu_data *rdp)
         }
         smp_mb(); /* List handling before counting for rcu_barrier(). */
         rdp->qlen_lazy -= count_lazy;
-        ACCESS_ONCE(rdp->qlen) = rdp->qlen - count;
+        WRITE_ONCE(rdp->qlen, rdp->qlen - count);
         rdp->n_cbs_invoked += count;
 
         /* Reinstate batch limit if we have worked down the excess. */
@@ -2793,7 +2794,7 @@ static void force_quiescent_state(struct rcu_state *rsp)
         /* Funnel through hierarchy to reduce memory contention. */
         rnp = __this_cpu_read(rsp->rda->mynode);
         for (; rnp != NULL; rnp = rnp->parent) {
-                ret = (ACCESS_ONCE(rsp->gp_flags) & RCU_GP_FLAG_FQS) ||
+                ret = (READ_ONCE(rsp->gp_flags) & RCU_GP_FLAG_FQS) ||
                       !raw_spin_trylock(&rnp->fqslock);
                 if (rnp_old != NULL)
                         raw_spin_unlock(&rnp_old->fqslock);
@@ -2809,13 +2810,12 @@ static void force_quiescent_state(struct rcu_state *rsp)
         raw_spin_lock_irqsave(&rnp_old->lock, flags);
         smp_mb__after_unlock_lock();
         raw_spin_unlock(&rnp_old->fqslock);
-        if (ACCESS_ONCE(rsp->gp_flags) & RCU_GP_FLAG_FQS) {
+        if (READ_ONCE(rsp->gp_flags) & RCU_GP_FLAG_FQS) {
                 rsp->n_force_qs_lh++;
                 raw_spin_unlock_irqrestore(&rnp_old->lock, flags);
                 return;  /* Someone beat us to it. */
         }
-        ACCESS_ONCE(rsp->gp_flags) =
-                ACCESS_ONCE(rsp->gp_flags) | RCU_GP_FLAG_FQS;
+        WRITE_ONCE(rsp->gp_flags, READ_ONCE(rsp->gp_flags) | RCU_GP_FLAG_FQS);
         raw_spin_unlock_irqrestore(&rnp_old->lock, flags);
         rcu_gp_kthread_wake(rsp);
 }
@@ -2881,7 +2881,7 @@ static void rcu_process_callbacks(struct softirq_action *unused)
  */
 static void invoke_rcu_callbacks(struct rcu_state *rsp, struct rcu_data *rdp)
 {
-        if (unlikely(!ACCESS_ONCE(rcu_scheduler_fully_active)))
+        if (unlikely(!READ_ONCE(rcu_scheduler_fully_active)))
                 return;
         if (likely(!rsp->boost)) {
                 rcu_do_batch(rsp, rdp);
@@ -2972,7 +2972,7 @@ __call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu),
         WARN_ON_ONCE((unsigned long)head & 0x1); /* Misaligned rcu_head! */
         if (debug_rcu_head_queue(head)) {
                 /* Probable double call_rcu(), so leak the callback. */
-                ACCESS_ONCE(head->func) = rcu_leak_callback;
+                WRITE_ONCE(head->func, rcu_leak_callback);
                 WARN_ONCE(1, "__call_rcu(): Leaked duplicate callback\n");
                 return;
         }
@@ -3011,7 +3011,7 @@ __call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu),
                 if (!likely(rdp->nxtlist))
                         init_default_callback_list(rdp);
         }
-        ACCESS_ONCE(rdp->qlen) = rdp->qlen + 1;
+        WRITE_ONCE(rdp->qlen, rdp->qlen + 1);
         if (lazy)
                 rdp->qlen_lazy++;
         else
@@ -3450,14 +3450,14 @@ static int __rcu_pending(struct rcu_state *rsp, struct rcu_data *rdp)
         }
 
         /* Has another RCU grace period completed?  */
-        if (ACCESS_ONCE(rnp->completed) != rdp->completed) { /* outside lock */
+        if (READ_ONCE(rnp->completed) != rdp->completed) { /* outside lock */
                 rdp->n_rp_gp_completed++;
                 return 1;
         }
 
         /* Has a new RCU grace period started? */
-        if (ACCESS_ONCE(rnp->gpnum) != rdp->gpnum ||
-            unlikely(ACCESS_ONCE(rdp->gpwrap))) { /* outside lock */
+        if (READ_ONCE(rnp->gpnum) != rdp->gpnum ||
+            unlikely(READ_ONCE(rdp->gpwrap))) { /* outside lock */
                 rdp->n_rp_gp_started++;
                 return 1;
         }
@@ -3564,7 +3564,7 @@ static void _rcu_barrier(struct rcu_state *rsp)
 {
         int cpu;
         struct rcu_data *rdp;
-        unsigned long snap = ACCESS_ONCE(rsp->n_barrier_done);
+        unsigned long snap = READ_ONCE(rsp->n_barrier_done);
         unsigned long snap_done;
 
         _rcu_barrier_trace(rsp, "Begin", -1, snap);
@@ -3606,10 +3606,10 @@ static void _rcu_barrier(struct rcu_state *rsp)
 
         /*
          * Increment ->n_barrier_done to avoid duplicate work.  Use
-         * ACCESS_ONCE() to prevent the compiler from speculating
+         * WRITE_ONCE() to prevent the compiler from speculating
          * the increment to precede the early-exit check.
          */
-        ACCESS_ONCE(rsp->n_barrier_done) = rsp->n_barrier_done + 1;
+        WRITE_ONCE(rsp->n_barrier_done, rsp->n_barrier_done + 1);
         WARN_ON_ONCE((rsp->n_barrier_done & 0x1) != 1);
         _rcu_barrier_trace(rsp, "Inc1", -1, rsp->n_barrier_done);
         smp_mb(); /* Order ->n_barrier_done increment with below mechanism. */
@@ -3645,7 +3645,7 @@ static void _rcu_barrier(struct rcu_state *rsp)
                                 __call_rcu(&rdp->barrier_head,
                                            rcu_barrier_callback, rsp, cpu, 0);
                         }
-                } else if (ACCESS_ONCE(rdp->qlen)) {
+                } else if (READ_ONCE(rdp->qlen)) {
                         _rcu_barrier_trace(rsp, "OnlineQ", cpu,
                                            rsp->n_barrier_done);
                         smp_call_function_single(cpu, rcu_barrier_func, rsp, 1);
@@ -3665,7 +3665,7 @@ static void _rcu_barrier(struct rcu_state *rsp)
 
         /* Increment ->n_barrier_done to prevent duplicate work. */
         smp_mb(); /* Keep increment after above mechanism. */
-        ACCESS_ONCE(rsp->n_barrier_done) = rsp->n_barrier_done + 1;
+        WRITE_ONCE(rsp->n_barrier_done, rsp->n_barrier_done + 1);
         WARN_ON_ONCE((rsp->n_barrier_done & 0x1) != 0);
         _rcu_barrier_trace(rsp, "Inc2", -1, rsp->n_barrier_done);
         smp_mb(); /* Keep increment before caller's subsequent code. */
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 8c0ec0f5a027..58b1ebdc4387 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -570,7 +570,7 @@ static int rcu_preempted_readers_exp(struct rcu_node *rnp)
 static int sync_rcu_preempt_exp_done(struct rcu_node *rnp)
 {
         return !rcu_preempted_readers_exp(rnp) &&
-               ACCESS_ONCE(rnp->expmask) == 0;
+               READ_ONCE(rnp->expmask) == 0;
 }
 
 /*
@@ -716,7 +716,7 @@ void synchronize_rcu_expedited(void)
         int trycount = 0;
 
         smp_mb(); /* Caller's modifications seen first by other CPUs. */
-        snap = ACCESS_ONCE(sync_rcu_preempt_exp_count) + 1;
+        snap = READ_ONCE(sync_rcu_preempt_exp_count) + 1;
         smp_mb(); /* Above access cannot bleed into critical section. */
 
         /*
@@ -740,7 +740,7 @@ void synchronize_rcu_expedited(void)
          */
         while (!mutex_trylock(&sync_rcu_preempt_exp_mutex)) {
                 if (ULONG_CMP_LT(snap,
-                    ACCESS_ONCE(sync_rcu_preempt_exp_count))) {
+                    READ_ONCE(sync_rcu_preempt_exp_count))) {
                         put_online_cpus();
                         goto mb_ret; /* Others did our work for us. */
                 }
@@ -752,7 +752,7 @@ void synchronize_rcu_expedited(void)
                         return;
                 }
         }
-        if (ULONG_CMP_LT(snap, ACCESS_ONCE(sync_rcu_preempt_exp_count))) {
+        if (ULONG_CMP_LT(snap, READ_ONCE(sync_rcu_preempt_exp_count))) {
                 put_online_cpus();
                 goto unlock_mb_ret; /* Others did our work for us. */
         }
@@ -780,8 +780,7 @@ void synchronize_rcu_expedited(void)
 
         /* Clean up and exit. */
         smp_mb(); /* ensure expedited GP seen before counter increment. */
-        ACCESS_ONCE(sync_rcu_preempt_exp_count) =
-                                        sync_rcu_preempt_exp_count + 1;
+        WRITE_ONCE(sync_rcu_preempt_exp_count, sync_rcu_preempt_exp_count + 1);
 unlock_mb_ret:
         mutex_unlock(&sync_rcu_preempt_exp_mutex);
 mb_ret:
@@ -994,8 +993,8 @@ static int rcu_boost(struct rcu_node *rnp)
         struct task_struct *t;
         struct list_head *tb;
 
-        if (ACCESS_ONCE(rnp->exp_tasks) == NULL &&
-            ACCESS_ONCE(rnp->boost_tasks) == NULL)
+        if (READ_ONCE(rnp->exp_tasks) == NULL &&
+            READ_ONCE(rnp->boost_tasks) == NULL)
                 return 0;  /* Nothing left to boost. */
 
         raw_spin_lock_irqsave(&rnp->lock, flags);
@@ -1048,8 +1047,8 @@ static int rcu_boost(struct rcu_node *rnp)
         rt_mutex_lock(&rnp->boost_mtx);
         rt_mutex_unlock(&rnp->boost_mtx);  /* Then keep lockdep happy. */
 
-        return ACCESS_ONCE(rnp->exp_tasks) != NULL ||
-               ACCESS_ONCE(rnp->boost_tasks) != NULL;
+        return READ_ONCE(rnp->exp_tasks) != NULL ||
+               READ_ONCE(rnp->boost_tasks) != NULL;
 }
 
 /*
@@ -1462,7 +1461,7 @@ static bool __maybe_unused rcu_try_advance_all_cbs(void)
                  * callbacks not yet ready to invoke.
                  */
                 if ((rdp->completed != rnp->completed ||
-                     unlikely(ACCESS_ONCE(rdp->gpwrap))) &&
+                     unlikely(READ_ONCE(rdp->gpwrap))) &&
                     rdp->nxttail[RCU_DONE_TAIL] != rdp->nxttail[RCU_NEXT_TAIL])
                         note_gp_changes(rsp, rdp);
 
@@ -1534,7 +1533,7 @@ static void rcu_prepare_for_idle(void)
         int tne;
 
         /* Handle nohz enablement switches conservatively. */
-        tne = ACCESS_ONCE(tick_nohz_active);
+        tne = READ_ONCE(tick_nohz_active);
         if (tne != rdtp->tick_nohz_enabled_snap) {
                 if (rcu_cpu_has_callbacks(NULL))
                         invoke_rcu_core(); /* force nohz to see update. */
@@ -1760,7 +1759,7 @@ static void print_cpu_stall_info(struct rcu_state *rsp, int cpu)
                atomic_read(&rdtp->dynticks) & 0xfff,
                rdtp->dynticks_nesting, rdtp->dynticks_nmi_nesting,
                rdp->softirq_snap, kstat_softirqs_cpu(RCU_SOFTIRQ, cpu),
-               ACCESS_ONCE(rsp->n_force_qs) - rsp->n_force_qs_gpstart,
+               READ_ONCE(rsp->n_force_qs) - rsp->n_force_qs_gpstart,
                fast_no_hz);
 }
 
@@ -1898,11 +1897,11 @@ static void wake_nocb_leader(struct rcu_data *rdp, bool force)
 {
         struct rcu_data *rdp_leader = rdp->nocb_leader;
 
-        if (!ACCESS_ONCE(rdp_leader->nocb_kthread))
+        if (!READ_ONCE(rdp_leader->nocb_kthread))
                 return;
-        if (ACCESS_ONCE(rdp_leader->nocb_leader_sleep) || force) {
+        if (READ_ONCE(rdp_leader->nocb_leader_sleep) || force) {
                 /* Prior smp_mb__after_atomic() orders against prior enqueue. */
-                ACCESS_ONCE(rdp_leader->nocb_leader_sleep) = false;
+                WRITE_ONCE(rdp_leader->nocb_leader_sleep, false);
                 wake_up(&rdp_leader->nocb_wq);
         }
 }
@@ -1934,14 +1933,14 @@ static bool rcu_nocb_cpu_needs_barrier(struct rcu_state *rsp, int cpu)
         ret = atomic_long_read(&rdp->nocb_q_count);
 
 #ifdef CONFIG_PROVE_RCU
-        rhp = ACCESS_ONCE(rdp->nocb_head);
+        rhp = READ_ONCE(rdp->nocb_head);
         if (!rhp)
-                rhp = ACCESS_ONCE(rdp->nocb_gp_head);
+                rhp = READ_ONCE(rdp->nocb_gp_head);
         if (!rhp)
-                rhp = ACCESS_ONCE(rdp->nocb_follower_head);
+                rhp = READ_ONCE(rdp->nocb_follower_head);
 
         /* Having no rcuo kthread but CBs after scheduler starts is bad! */
-        if (!ACCESS_ONCE(rdp->nocb_kthread) && rhp &&
+        if (!READ_ONCE(rdp->nocb_kthread) && rhp &&
             rcu_scheduler_fully_active) {
                 /* RCU callback enqueued before CPU first came online??? */
                 pr_err("RCU: Never-onlined no-CBs CPU %d has CB %p\n",
@@ -1975,12 +1974,12 @@ static void __call_rcu_nocb_enqueue(struct rcu_data *rdp,
         atomic_long_add(rhcount, &rdp->nocb_q_count);
         /* rcu_barrier() relies on ->nocb_q_count add before xchg. */
         old_rhpp = xchg(&rdp->nocb_tail, rhtp);
-        ACCESS_ONCE(*old_rhpp) = rhp;
+        WRITE_ONCE(*old_rhpp, rhp);
         atomic_long_add(rhcount_lazy, &rdp->nocb_q_count_lazy);
         smp_mb__after_atomic(); /* Store *old_rhpp before _wake test. */
 
         /* If we are not being polled and there is a kthread, awaken it ... */
-        t = ACCESS_ONCE(rdp->nocb_kthread);
+        t = READ_ONCE(rdp->nocb_kthread);
         if (rcu_nocb_poll || !t) {
                 trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu,
                                     TPS("WakeNotPoll"));
@@ -2118,7 +2117,7 @@ static void rcu_nocb_wait_gp(struct rcu_data *rdp)
         for (;;) {
                 wait_event_interruptible(
                         rnp->nocb_gp_wq[c & 0x1],
-                        (d = ULONG_CMP_GE(ACCESS_ONCE(rnp->completed), c)));
+                        (d = ULONG_CMP_GE(READ_ONCE(rnp->completed), c)));
                 if (likely(d))
                         break;
                 WARN_ON(signal_pending(current));
@@ -2145,7 +2144,7 @@ wait_again:
         if (!rcu_nocb_poll) {
                 trace_rcu_nocb_wake(my_rdp->rsp->name, my_rdp->cpu, "Sleep");
                 wait_event_interruptible(my_rdp->nocb_wq,
-                                !ACCESS_ONCE(my_rdp->nocb_leader_sleep));
+                                !READ_ONCE(my_rdp->nocb_leader_sleep));
                 /* Memory barrier handled by smp_mb() calls below and repoll. */
         } else if (firsttime) {
                 firsttime = false; /* Don't drown trace log with "Poll"! */
@@ -2159,12 +2158,12 @@ wait_again:
          */
         gotcbs = false;
         for (rdp = my_rdp; rdp; rdp = rdp->nocb_next_follower) {
-                rdp->nocb_gp_head = ACCESS_ONCE(rdp->nocb_head);
+                rdp->nocb_gp_head = READ_ONCE(rdp->nocb_head);
                 if (!rdp->nocb_gp_head)
                         continue;  /* No CBs here, try next follower. */
 
                 /* Move callbacks to wait-for-GP list, which is empty. */
-                ACCESS_ONCE(rdp->nocb_head) = NULL;
+                WRITE_ONCE(rdp->nocb_head, NULL);
                 rdp->nocb_gp_tail = xchg(&rdp->nocb_tail, &rdp->nocb_head);
                 gotcbs = true;
         }
@@ -2184,7 +2183,7 @@ wait_again:
                 my_rdp->nocb_leader_sleep = true;
                 smp_mb();  /* Ensure _sleep true before scan. */
                 for (rdp = my_rdp; rdp; rdp = rdp->nocb_next_follower)
-                        if (ACCESS_ONCE(rdp->nocb_head)) {
+                        if (READ_ONCE(rdp->nocb_head)) {
                                 /* Found CB, so short-circuit next wait. */
                                 my_rdp->nocb_leader_sleep = false;
                                 break;
@@ -2205,7 +2204,7 @@ wait_again:
 
         /* Each pass through the following loop wakes a follower, if needed. */
         for (rdp = my_rdp; rdp; rdp = rdp->nocb_next_follower) {
-                if (ACCESS_ONCE(rdp->nocb_head))
+                if (READ_ONCE(rdp->nocb_head))
                         my_rdp->nocb_leader_sleep = false;/* No need to sleep.*/
                 if (!rdp->nocb_gp_head)
                         continue; /* No CBs, so no need to wake follower. */
@@ -2241,7 +2240,7 @@ static void nocb_follower_wait(struct rcu_data *rdp)
                         trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu,
                                             "FollowerSleep");
                         wait_event_interruptible(rdp->nocb_wq,
-                                                 ACCESS_ONCE(rdp->nocb_follower_head));
+                                                 READ_ONCE(rdp->nocb_follower_head));
                 } else if (firsttime) {
                         /* Don't drown trace log with "Poll"! */
                         firsttime = false;
@@ -2282,10 +2281,10 @@ static int rcu_nocb_kthread(void *arg)
                         nocb_follower_wait(rdp);
 
                 /* Pull the ready-to-invoke callbacks onto local list. */
-                list = ACCESS_ONCE(rdp->nocb_follower_head);
+                list = READ_ONCE(rdp->nocb_follower_head);
                 BUG_ON(!list);
                 trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, "WokeNonEmpty");
-                ACCESS_ONCE(rdp->nocb_follower_head) = NULL;
+                WRITE_ONCE(rdp->nocb_follower_head, NULL);
                 tail = xchg(&rdp->nocb_follower_tail, &rdp->nocb_follower_head);
 
                 /* Each pass through the following loop invokes a callback. */
@@ -2324,7 +2323,7 @@ static int rcu_nocb_kthread(void *arg)
 /* Is a deferred wakeup of rcu_nocb_kthread() required? */
 static int rcu_nocb_need_deferred_wakeup(struct rcu_data *rdp)
 {
-        return ACCESS_ONCE(rdp->nocb_defer_wakeup);
+        return READ_ONCE(rdp->nocb_defer_wakeup);
 }
 
 /* Do a deferred wakeup of rcu_nocb_kthread(). */
@@ -2334,8 +2333,8 @@ static void do_nocb_deferred_wakeup(struct rcu_data *rdp)
 
         if (!rcu_nocb_need_deferred_wakeup(rdp))
                 return;
-        ndw = ACCESS_ONCE(rdp->nocb_defer_wakeup);
-        ACCESS_ONCE(rdp->nocb_defer_wakeup) = RCU_NOGP_WAKE_NOT;
+        ndw = READ_ONCE(rdp->nocb_defer_wakeup);
+        WRITE_ONCE(rdp->nocb_defer_wakeup, RCU_NOGP_WAKE_NOT);
         wake_nocb_leader(rdp, ndw == RCU_NOGP_WAKE_FORCE);
         trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, TPS("DeferredWake"));
 }
@@ -2448,7 +2447,7 @@ static void rcu_spawn_one_nocb_kthread(struct rcu_state *rsp, int cpu)
         t = kthread_run(rcu_nocb_kthread, rdp_spawn,
                         "rcuo%c/%d", rsp->abbr, cpu);
         BUG_ON(IS_ERR(t));
-        ACCESS_ONCE(rdp_spawn->nocb_kthread) = t;
+        WRITE_ONCE(rdp_spawn->nocb_kthread, t);
 }
 
 /*
@@ -2663,7 +2662,7 @@ static void rcu_sysidle_enter(int irq)
 
         /* Record start of fully idle period. */
         j = jiffies;
-        ACCESS_ONCE(rdtp->dynticks_idle_jiffies) = j;
+        WRITE_ONCE(rdtp->dynticks_idle_jiffies, j);
         smp_mb__before_atomic();
         atomic_inc(&rdtp->dynticks_idle);
         smp_mb__after_atomic();
@@ -2681,7 +2680,7 @@ static void rcu_sysidle_enter(int irq)
  */
 void rcu_sysidle_force_exit(void)
 {
-        int oldstate = ACCESS_ONCE(full_sysidle_state);
+        int oldstate = READ_ONCE(full_sysidle_state);
         int newoldstate;
 
         /*
@@ -2794,7 +2793,7 @@ static void rcu_sysidle_check_cpu(struct rcu_data *rdp, bool *isidle,
         smp_mb(); /* Read counters before timestamps. */
 
         /* Pick up timestamps. */
-        j = ACCESS_ONCE(rdtp->dynticks_idle_jiffies);
+        j = READ_ONCE(rdtp->dynticks_idle_jiffies);
         /* If this CPU entered idle more recently, update maxj timestamp. */
         if (ULONG_CMP_LT(*maxj, j))
                 *maxj = j;
@@ -2831,11 +2830,11 @@ static unsigned long rcu_sysidle_delay(void)
 static void rcu_sysidle(unsigned long j)
 {
         /* Check the current state. */
-        switch (ACCESS_ONCE(full_sysidle_state)) {
+        switch (READ_ONCE(full_sysidle_state)) {
         case RCU_SYSIDLE_NOT:
 
                 /* First time all are idle, so note a short idle period. */
-                ACCESS_ONCE(full_sysidle_state) = RCU_SYSIDLE_SHORT;
+                WRITE_ONCE(full_sysidle_state, RCU_SYSIDLE_SHORT);
                 break;
 
         case RCU_SYSIDLE_SHORT:
@@ -2873,7 +2872,7 @@ static void rcu_sysidle_cancel(void)
 {
         smp_mb();
         if (full_sysidle_state > RCU_SYSIDLE_SHORT)
-                ACCESS_ONCE(full_sysidle_state) = RCU_SYSIDLE_NOT;
+                WRITE_ONCE(full_sysidle_state, RCU_SYSIDLE_NOT);
 }
 
 /*
@@ -2925,7 +2924,7 @@ static void rcu_sysidle_cb(struct rcu_head *rhp)
         smp_mb();  /* grace period precedes setting inuse. */
 
         rshp = container_of(rhp, struct rcu_sysidle_head, rh);
-        ACCESS_ONCE(rshp->inuse) = 0;
+        WRITE_ONCE(rshp->inuse, 0);
 }
 
 /*
@@ -2936,7 +2935,7 @@ static void rcu_sysidle_cb(struct rcu_head *rhp)
 bool rcu_sys_is_idle(void)
 {
         static struct rcu_sysidle_head rsh;
-        int rss = ACCESS_ONCE(full_sysidle_state);
+        int rss = READ_ONCE(full_sysidle_state);
 
         if (WARN_ON_ONCE(smp_processor_id() != tick_do_timer_cpu))
                 return false;
@@ -2964,7 +2963,7 @@ bool rcu_sys_is_idle(void)
                         }
                         rcu_sysidle_report(rcu_state_p, isidle, maxj, false);
                         oldrss = rss;
-                        rss = ACCESS_ONCE(full_sysidle_state);
+                        rss = READ_ONCE(full_sysidle_state);
                 }
         }
 
@@ -3048,7 +3047,7 @@ static bool rcu_nohz_full_cpu(struct rcu_state *rsp)
 #ifdef CONFIG_NO_HZ_FULL
         if (tick_nohz_full_cpu(smp_processor_id()) &&
             (!rcu_gp_in_progress(rsp) ||
-             ULONG_CMP_LT(jiffies, ACCESS_ONCE(rsp->gp_start) + HZ)))
+             ULONG_CMP_LT(jiffies, READ_ONCE(rsp->gp_start) + HZ)))
                 return 1;
 #endif /* #ifdef CONFIG_NO_HZ_FULL */
         return 0;
@@ -3077,7 +3076,7 @@ static void rcu_bind_gp_kthread(void)
 static void rcu_dynticks_task_enter(void)
 {
 #if defined(CONFIG_TASKS_RCU) && defined(CONFIG_NO_HZ_FULL)
-        ACCESS_ONCE(current->rcu_tasks_idle_cpu) = smp_processor_id();
+        WRITE_ONCE(current->rcu_tasks_idle_cpu, smp_processor_id());
 #endif /* #if defined(CONFIG_TASKS_RCU) && defined(CONFIG_NO_HZ_FULL) */
 }
 
@@ -3085,6 +3084,6 @@ static void rcu_dynticks_task_enter(void)
 static void rcu_dynticks_task_exit(void)
 {
 #if defined(CONFIG_TASKS_RCU) && defined(CONFIG_NO_HZ_FULL)
-        ACCESS_ONCE(current->rcu_tasks_idle_cpu) = -1;
+        WRITE_ONCE(current->rcu_tasks_idle_cpu, -1);
 #endif /* #if defined(CONFIG_TASKS_RCU) && defined(CONFIG_NO_HZ_FULL) */
 }
diff --git a/kernel/rcu/tree_trace.c b/kernel/rcu/tree_trace.c
index f92361efd0f5..3ea7ffc7d5c4 100644
--- a/kernel/rcu/tree_trace.c
+++ b/kernel/rcu/tree_trace.c
@@ -277,7 +277,7 @@ static void print_one_rcu_state(struct seq_file *m, struct rcu_state *rsp)
         seq_printf(m, "nfqs=%lu/nfqsng=%lu(%lu) fqlh=%lu oqlen=%ld/%ld\n",
                    rsp->n_force_qs, rsp->n_force_qs_ngp,
                    rsp->n_force_qs - rsp->n_force_qs_ngp,
-                   ACCESS_ONCE(rsp->n_force_qs_lh), rsp->qlen_lazy, rsp->qlen);
+                   READ_ONCE(rsp->n_force_qs_lh), rsp->qlen_lazy, rsp->qlen);
         for (rnp = &rsp->node[0]; rnp - &rsp->node[0] < rcu_num_nodes; rnp++) {
                 if (rnp->level != level) {
                         seq_puts(m, "\n");
@@ -323,8 +323,8 @@ static void show_one_rcugp(struct seq_file *m, struct rcu_state *rsp)
         struct rcu_node *rnp = &rsp->node[0];
 
         raw_spin_lock_irqsave(&rnp->lock, flags);
-        completed = ACCESS_ONCE(rsp->completed);
-        gpnum = ACCESS_ONCE(rsp->gpnum);
+        completed = READ_ONCE(rsp->completed);
+        gpnum = READ_ONCE(rsp->gpnum);
         if (completed == gpnum)
                 gpage = 0;
         else
diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c
index 1f133350da01..afaecb7a799a 100644
--- a/kernel/rcu/update.c
+++ b/kernel/rcu/update.c
@@ -150,14 +150,14 @@ void __rcu_read_unlock(void)
                 barrier();  /* critical section before exit code. */
                 t->rcu_read_lock_nesting = INT_MIN;
                 barrier();  /* assign before ->rcu_read_unlock_special load */
-                if (unlikely(ACCESS_ONCE(t->rcu_read_unlock_special.s)))
+                if (unlikely(READ_ONCE(t->rcu_read_unlock_special.s)))
                         rcu_read_unlock_special(t);
                 barrier();  /* ->rcu_read_unlock_special load before assign */
                 t->rcu_read_lock_nesting = 0;
         }
 #ifdef CONFIG_PROVE_LOCKING
         {
-                int rrln = ACCESS_ONCE(t->rcu_read_lock_nesting);
+                int rrln = READ_ONCE(t->rcu_read_lock_nesting);
 
                 WARN_ON_ONCE(rrln < 0 && rrln > INT_MIN / 2);
         }
@@ -389,17 +389,17 @@ module_param(rcu_cpu_stall_timeout, int, 0644);
 
 int rcu_jiffies_till_stall_check(void)
 {
-        int till_stall_check = ACCESS_ONCE(rcu_cpu_stall_timeout);
+        int till_stall_check = READ_ONCE(rcu_cpu_stall_timeout);
 
         /*
          * Limit check must be consistent with the Kconfig limits
          * for CONFIG_RCU_CPU_STALL_TIMEOUT.
          */
         if (till_stall_check < 3) {
-                ACCESS_ONCE(rcu_cpu_stall_timeout) = 3;
+                WRITE_ONCE(rcu_cpu_stall_timeout, 3);
                 till_stall_check = 3;
         } else if (till_stall_check > 300) {
-                ACCESS_ONCE(rcu_cpu_stall_timeout) = 300;
+                WRITE_ONCE(rcu_cpu_stall_timeout, 300);
                 till_stall_check = 300;
         }
         return till_stall_check * HZ + RCU_STALL_DELAY_DELTA;
@@ -550,12 +550,12 @@ static void check_holdout_task(struct task_struct *t,
 {
         int cpu;
 
-        if (!ACCESS_ONCE(t->rcu_tasks_holdout) ||
-            t->rcu_tasks_nvcsw != ACCESS_ONCE(t->nvcsw) ||
-            !ACCESS_ONCE(t->on_rq) ||
+        if (!READ_ONCE(t->rcu_tasks_holdout) ||
+            t->rcu_tasks_nvcsw != READ_ONCE(t->nvcsw) ||
+            !READ_ONCE(t->on_rq) ||
             (IS_ENABLED(CONFIG_NO_HZ_FULL) &&
              !is_idle_task(t) && t->rcu_tasks_idle_cpu >= 0)) {
-                ACCESS_ONCE(t->rcu_tasks_holdout) = false;
+                WRITE_ONCE(t->rcu_tasks_holdout, false);
                 list_del_init(&t->rcu_tasks_holdout_list);
                 put_task_struct(t);
                 return;
@@ -639,11 +639,11 @@ static int __noreturn rcu_tasks_kthread(void *arg)
                  */
                 rcu_read_lock();
                 for_each_process_thread(g, t) {
-                        if (t != current && ACCESS_ONCE(t->on_rq) &&
+                        if (t != current && READ_ONCE(t->on_rq) &&
                             !is_idle_task(t)) {
                                 get_task_struct(t);
-                                t->rcu_tasks_nvcsw = ACCESS_ONCE(t->nvcsw);
-                                ACCESS_ONCE(t->rcu_tasks_holdout) = true;
+                                t->rcu_tasks_nvcsw = READ_ONCE(t->nvcsw);
+                                WRITE_ONCE(t->rcu_tasks_holdout, true);
                                 list_add(&t->rcu_tasks_holdout_list,
                                          &rcu_tasks_holdouts);
                         }
@@ -672,7 +672,7 @@ static int __noreturn rcu_tasks_kthread(void *arg)
                         struct task_struct *t1;
 
                         schedule_timeout_interruptible(HZ);
-                        rtst = ACCESS_ONCE(rcu_task_stall_timeout);
+                        rtst = READ_ONCE(rcu_task_stall_timeout);
                         needreport = rtst > 0 &&
                                      time_after(jiffies, lastreport + rtst);
                         if (needreport)
@@ -728,7 +728,7 @@ static void rcu_spawn_tasks_kthread(void)
         static struct task_struct *rcu_tasks_kthread_ptr;
         struct task_struct *t;
 
-        if (ACCESS_ONCE(rcu_tasks_kthread_ptr)) {
+        if (READ_ONCE(rcu_tasks_kthread_ptr)) {
                 smp_mb(); /* Ensure caller sees full kthread. */
                 return;
         }
@@ -740,7 +740,7 @@ static void rcu_spawn_tasks_kthread(void)
         t = kthread_run(rcu_tasks_kthread, NULL, "rcu_tasks_kthread");
         BUG_ON(IS_ERR(t));
         smp_mb(); /* Ensure others see full kthread. */
-        ACCESS_ONCE(rcu_tasks_kthread_ptr) = t;
+        WRITE_ONCE(rcu_tasks_kthread_ptr, t);
         mutex_unlock(&rcu_tasks_kthread_mutex);
 }