rcu: Convert to raw_spinlocks

The spinlocks in rcutree need to be real spinlocks in
preempt-rt. Convert them to raw_spinlocks.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
LKML-Reference: <1266887105-1528-18-git-send-email-paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 23 insertions, 23 deletions

diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h
index a82566696b0b..a8b2e834fd3a 100644
--- a/kernel/rcutree_plugin.h
+++ b/kernel/rcutree_plugin.h
@@ -111,7 +111,7 @@ static void rcu_preempt_note_context_switch(int cpu)
                 /* Possibly blocking in an RCU read-side critical section. */
                 rdp = rcu_preempt_state.rda[cpu];
                 rnp = rdp->mynode;
-                spin_lock_irqsave(&rnp->lock, flags);
+                raw_spin_lock_irqsave(&rnp->lock, flags);
                 t->rcu_read_unlock_special |= RCU_READ_UNLOCK_BLOCKED;
                 t->rcu_blocked_node = rnp;
 
@@ -132,7 +132,7 @@ static void rcu_preempt_note_context_switch(int cpu)
                 WARN_ON_ONCE(!list_empty(&t->rcu_node_entry));
                 phase = (rnp->gpnum + !(rnp->qsmask & rdp->grpmask)) & 0x1;
                 list_add(&t->rcu_node_entry, &rnp->blocked_tasks[phase]);
-                spin_unlock_irqrestore(&rnp->lock, flags);
+                raw_spin_unlock_irqrestore(&rnp->lock, flags);
         }
 
         /*
@@ -189,7 +189,7 @@ static void rcu_report_unblock_qs_rnp(struct rcu_node *rnp, unsigned long flags)
         struct rcu_node *rnp_p;
 
         if (rnp->qsmask != 0 || rcu_preempted_readers(rnp)) {
-                spin_unlock_irqrestore(&rnp->lock, flags);
+                raw_spin_unlock_irqrestore(&rnp->lock, flags);
                 return;  /* Still need more quiescent states! */
         }
 
@@ -206,8 +206,8 @@ static void rcu_report_unblock_qs_rnp(struct rcu_node *rnp, unsigned long flags)
 
         /* Report up the rest of the hierarchy. */
         mask = rnp->grpmask;
-        spin_unlock(&rnp->lock);        /* irqs remain disabled. */
-        spin_lock(&rnp_p->lock);        /* irqs already disabled. */
+        raw_spin_unlock(&rnp->lock);    /* irqs remain disabled. */
+        raw_spin_lock(&rnp_p->lock);    /* irqs already disabled. */
         rcu_report_qs_rnp(mask, &rcu_preempt_state, rnp_p, flags);
 }
 
@@ -257,10 +257,10 @@ static void rcu_read_unlock_special(struct task_struct *t)
                  */
                 for (;;) {
                         rnp = t->rcu_blocked_node;
-                        spin_lock(&rnp->lock);  /* irqs already disabled. */
+                        raw_spin_lock(&rnp->lock);  /* irqs already disabled. */
                         if (rnp == t->rcu_blocked_node)
                                 break;
-                        spin_unlock(&rnp->lock);  /* irqs remain disabled. */
+                        raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */
                 }
                 empty = !rcu_preempted_readers(rnp);
                 empty_exp = !rcu_preempted_readers_exp(rnp);
@@ -274,7 +274,7 @@ static void rcu_read_unlock_special(struct task_struct *t)
                  * Note that rcu_report_unblock_qs_rnp() releases rnp->lock.
                  */
                 if (empty)
-                        spin_unlock_irqrestore(&rnp->lock, flags);
+                        raw_spin_unlock_irqrestore(&rnp->lock, flags);
                 else
                         rcu_report_unblock_qs_rnp(rnp, flags);
 
@@ -324,12 +324,12 @@ static void rcu_print_task_stall(struct rcu_node *rnp)
         struct task_struct *t;
 
         if (rcu_preempted_readers(rnp)) {
-                spin_lock_irqsave(&rnp->lock, flags);
+                raw_spin_lock_irqsave(&rnp->lock, flags);
                 phase = rnp->gpnum & 0x1;
                 lp = &rnp->blocked_tasks[phase];
                 list_for_each_entry(t, lp, rcu_node_entry)
                         printk(" P%d", t->pid);
-                spin_unlock_irqrestore(&rnp->lock, flags);
+                raw_spin_unlock_irqrestore(&rnp->lock, flags);
         }
 }
 
@@ -400,11 +400,11 @@ static int rcu_preempt_offline_tasks(struct rcu_state *rsp,
                 lp_root = &rnp_root->blocked_tasks[i];
                 while (!list_empty(lp)) {
                         tp = list_entry(lp->next, typeof(*tp), rcu_node_entry);
-                        spin_lock(&rnp_root->lock); /* irqs already disabled */
+                        raw_spin_lock(&rnp_root->lock); /* irqs already disabled */
                         list_del(&tp->rcu_node_entry);
                         tp->rcu_blocked_node = rnp_root;
                         list_add(&tp->rcu_node_entry, lp_root);
-                        spin_unlock(&rnp_root->lock); /* irqs remain disabled */
+                        raw_spin_unlock(&rnp_root->lock); /* irqs remain disabled */
                 }
         }
         return retval;
@@ -528,7 +528,7 @@ static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp)
         unsigned long flags;
         unsigned long mask;
 
-        spin_lock_irqsave(&rnp->lock, flags);
+        raw_spin_lock_irqsave(&rnp->lock, flags);
         for (;;) {
                 if (!sync_rcu_preempt_exp_done(rnp))
                         break;
@@ -537,12 +537,12 @@ static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp)
                         break;
                 }
                 mask = rnp->grpmask;
-                spin_unlock(&rnp->lock); /* irqs remain disabled */
+                raw_spin_unlock(&rnp->lock); /* irqs remain disabled */
                 rnp = rnp->parent;
-                spin_lock(&rnp->lock); /* irqs already disabled */
+                raw_spin_lock(&rnp->lock); /* irqs already disabled */
                 rnp->expmask &= ~mask;
         }
-        spin_unlock_irqrestore(&rnp->lock, flags);
+        raw_spin_unlock_irqrestore(&rnp->lock, flags);
 }
 
 /*
@@ -557,11 +557,11 @@ sync_rcu_preempt_exp_init(struct rcu_state *rsp, struct rcu_node *rnp)
 {
         int must_wait;
 
-        spin_lock(&rnp->lock); /* irqs already disabled */
+        raw_spin_lock(&rnp->lock); /* irqs already disabled */
         list_splice_init(&rnp->blocked_tasks[0], &rnp->blocked_tasks[2]);
         list_splice_init(&rnp->blocked_tasks[1], &rnp->blocked_tasks[3]);
         must_wait = rcu_preempted_readers_exp(rnp);
-        spin_unlock(&rnp->lock); /* irqs remain disabled */
+        raw_spin_unlock(&rnp->lock); /* irqs remain disabled */
         if (!must_wait)
                 rcu_report_exp_rnp(rsp, rnp);
 }
@@ -606,13 +606,13 @@ void synchronize_rcu_expedited(void)
         /* force all RCU readers onto blocked_tasks[]. */
         synchronize_sched_expedited();
 
-        spin_lock_irqsave(&rsp->onofflock, flags);
+        raw_spin_lock_irqsave(&rsp->onofflock, flags);
 
         /* Initialize ->expmask for all non-leaf rcu_node structures. */
         rcu_for_each_nonleaf_node_breadth_first(rsp, rnp) {
-                spin_lock(&rnp->lock); /* irqs already disabled. */
+                raw_spin_lock(&rnp->lock); /* irqs already disabled. */
                 rnp->expmask = rnp->qsmaskinit;
-                spin_unlock(&rnp->lock); /* irqs remain disabled. */
+                raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */
         }
 
         /* Snapshot current state of ->blocked_tasks[] lists. */
@@ -621,7 +621,7 @@ void synchronize_rcu_expedited(void)
         if (NUM_RCU_NODES > 1)
                 sync_rcu_preempt_exp_init(rsp, rcu_get_root(rsp));
 
-        spin_unlock_irqrestore(&rsp->onofflock, flags);
+        raw_spin_unlock_irqrestore(&rsp->onofflock, flags);
 
         /* Wait for snapshotted ->blocked_tasks[] lists to drain. */
         rnp = rcu_get_root(rsp);
@@ -756,7 +756,7 @@ static int rcu_preempted_readers(struct rcu_node *rnp)
 /* Because preemptible RCU does not exist, no quieting of tasks. */
 static void rcu_report_unblock_qs_rnp(struct rcu_node *rnp, unsigned long flags)
 {
-        spin_unlock_irqrestore(&rnp->lock, flags);
+        raw_spin_unlock_irqrestore(&rnp->lock, flags);
 }
 
 #endif /* #ifdef CONFIG_HOTPLUG_CPU */