commit 80d02085d99039b3b7f3a73c8896226b0cb1ba07
author Paul E. McKenney <paulmck@linux.vnet.ibm.com> Thu May 12 01:08:07 2011 -0700
committer Ingo Molnar <mingo@elte.hu> Thu May 19 23:25:29 2011 +0200
tree c310902423ecb00effadcb59c60cbf118d4037cb
parent 11c476f31a0fabc6e604da5b09a6590b57c3fb20

Revert "rcu: Decrease memory-barrier usage based on semi-formal proof"

This reverts commit e59fb3120becfb36b22ddb8bd27d065d3cdca499.

This reversion was due to (extreme) boot-time slowdowns on SPARC seen by
Yinghai Lu and on x86 by Ingo
.
This is a non-trivial reversion due to intervening commits.

Conflicts:

	Documentation/RCU/trace.txt
	kernel/rcutree.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>

kernel/rcutree_trace.c

diff --git a/kernel/rcutree_trace.c b/kernel/rcutree_trace.c
index 9678cc3..aa0fd72 100644
--- a/kernel/rcutree_trace.c
+++ b/kernel/rcutree_trace.c
@@ -69,10 +69,10 @@
 		   rdp->passed_quiesc, rdp->passed_quiesc_completed,
 		   rdp->qs_pending);
 #ifdef CONFIG_NO_HZ
-	seq_printf(m, " dt=%d/%d/%d df=%lu",
-		   atomic_read(&rdp->dynticks->dynticks),
+	seq_printf(m, " dt=%d/%d dn=%d df=%lu",
+		   rdp->dynticks->dynticks,
 		   rdp->dynticks->dynticks_nesting,
-		   rdp->dynticks->dynticks_nmi_nesting,
+		   rdp->dynticks->dynticks_nmi,
 		   rdp->dynticks_fqs);
 #endif /* #ifdef CONFIG_NO_HZ */
 	seq_printf(m, " of=%lu ri=%lu", rdp->offline_fqs, rdp->resched_ipi);
@@ -141,9 +141,9 @@
 		   rdp->qs_pending);
 #ifdef CONFIG_NO_HZ
 	seq_printf(m, ",%d,%d,%d,%lu",
-		   atomic_read(&rdp->dynticks->dynticks),
+		   rdp->dynticks->dynticks,
 		   rdp->dynticks->dynticks_nesting,
-		   rdp->dynticks->dynticks_nmi_nesting,
+		   rdp->dynticks->dynticks_nmi,
 		   rdp->dynticks_fqs);
 #endif /* #ifdef CONFIG_NO_HZ */
 	seq_printf(m, ",%lu,%lu", rdp->offline_fqs, rdp->resched_ipi);
@@ -167,7 +167,7 @@
 {
 	seq_puts(m, "\"CPU\",\"Online?\",\"c\",\"g\",\"pq\",\"pqc\",\"pq\",");
 #ifdef CONFIG_NO_HZ
-	seq_puts(m, "\"dt\",\"dt nesting\",\"dt NMI nesting\",\"df\",");
+	seq_puts(m, "\"dt\",\"dt nesting\",\"dn\",\"df\",");
 #endif /* #ifdef CONFIG_NO_HZ */
 	seq_puts(m, "\"of\",\"ri\",\"ql\",\"b\",\"ci\",\"co\",\"ca\"\n");
 #ifdef CONFIG_TREE_PREEMPT_RCU