From 77583d0c191f2897c2a44cbbce0c4dec050fb3ae Mon Sep 17 00:00:00 2001
From: Ingo Molnar <mingo@elte.hu>
Date: Fri, 3 Jul 2009 08:30:13 -0500
Subject: [PATCH] mm-memory-rt

commit 8a56ce758d645882ffbc920efd1d409c4ff83641 in tip.

On RT this is not a critical code path. It's preemptible so we go for
the PREEMPT=n case as well.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/mm/memory.c b/mm/memory.c
index 09e4b1b..3e88b30 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -974,10 +974,13 @@ static unsigned long unmap_page_range(struct mmu_gather *tlb,
 	return addr;
 }
 
-#ifdef CONFIG_PREEMPT
+#if defined(CONFIG_PREEMPT) && !defined(CONFIG_PREEMPT_RT)
 # define ZAP_BLOCK_SIZE	(8 * PAGE_SIZE)
 #else
-/* No preempt: go for improved straight-line efficiency */
+/*
+ * No preempt: go for improved straight-line efficiency
+ * on PREEMPT_RT this is not a critical latency-path.
+ */
 # define ZAP_BLOCK_SIZE	(1024 * PAGE_SIZE)
 #endif
 
-- 
1.7.1.1