rcu: Need to update rnp->gpnum if preemptable RCU is to be reliable

[pandora-kernel.git] / kernel / rcutree.c

diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index 6b11b07..c634a92 100644 (file)
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -632,6 +632,7 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
        /* Special-case the common single-level case. */
        if (NUM_RCU_NODES == 1) {
                rnp->qsmask = rnp->qsmaskinit;
+               rnp->gpnum = rsp->gpnum;
                rsp->signaled = RCU_SIGNAL_INIT; /* force_quiescent_state OK. */
                spin_unlock_irqrestore(&rnp->lock, flags);
                return;
@@ -657,8 +658,10 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
         */
 
        rnp_end = rsp->level[NUM_RCU_LVLS - 1];
-       for (rnp_cur = &rsp->node[0]; rnp_cur < rnp_end; rnp_cur++)
+       for (rnp_cur = &rsp->node[0]; rnp_cur < rnp_end; rnp_cur++) {
                rnp_cur->qsmask = rnp_cur->qsmaskinit;
+               rnp->gpnum = rsp->gpnum;
+       }
 
        /*
         * Now set up the leaf nodes.  Here we must be careful.  First,
@@ -679,6 +682,7 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
        for (; rnp_cur < rnp_end; rnp_cur++) {
                spin_lock(&rnp_cur->lock);      /* irqs already disabled. */
                rnp_cur->qsmask = rnp_cur->qsmaskinit;
+               rnp->gpnum = rsp->gpnum;
                spin_unlock(&rnp_cur->lock);    /* irqs already disabled. */
        }