linux-kernel - [PATCH 1/5] x86: Move enabling of PSE and PGE out of init_memory

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Date:	Fri, 24 Aug 2012 18:55:12 -0500
From:	Jacob Shin <jacob.shin@....com>
To:	X86-ML <x86@...nel.org>
CC:	LKML <linux-kernel@...r.kernel.org>,
	"H. Peter Anvin" <hpa@...or.com>, Yinghai Lu <yinghai@...nel.org>,
	Tejun Heo <tj@...nel.org>, Dave Young <dyoung@...hat.com>,
	Chao Wang <chaowang@...hat.com>,
	Vivek Goyal <vgoyal@...hat.com>,
	Andreas Herrmann <andreas.herrmann3@....com>,
	Borislav Petkov <borislav.petkov@....com>,
	Jacob Shin <jacob.shin@....com>
Subject: [PATCH 1/5] x86: Move enabling of PSE and PGE out of init_memory_mapping

Depending on the platform, init_memory_mapping() may be called multiple
times. Move it out to setup_arch() to avoid writing to cr4 on every call.

Signed-off-by: Jacob Shin <jacob.shin@....com>
---
 arch/x86/kernel/setup.c |   10 ++++++++++
 arch/x86/mm/init.c      |   10 ----------
 2 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index f4b9b80..751e020 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -913,6 +913,16 @@ void __init setup_arch(char **cmdline_p)
 
 	init_gbpages();
 
+	/* Enable PSE if available */
+	if (cpu_has_pse)
+		set_in_cr4(X86_CR4_PSE);
+
+	/* Enable PGE if available */
+	if (cpu_has_pge) {
+		set_in_cr4(X86_CR4_PGE);
+		__supported_pte_mask |= _PAGE_GLOBAL;
+	}
+
 	/* max_pfn_mapped is updated here */
 	max_low_pfn_mapped = init_memory_mapping(0, max_low_pfn<<PAGE_SHIFT);
 	max_pfn_mapped = max_low_pfn_mapped;
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index e0e6990..2f07e09 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -149,16 +149,6 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
 	use_gbpages = direct_gbpages;
 #endif
 
-	/* Enable PSE if available */
-	if (cpu_has_pse)
-		set_in_cr4(X86_CR4_PSE);
-
-	/* Enable PGE if available */
-	if (cpu_has_pge) {
-		set_in_cr4(X86_CR4_PGE);
-		__supported_pte_mask |= _PAGE_GLOBAL;
-	}
-
 	if (use_gbpages)
 		page_size_mask |= 1 << PG_LEVEL_1G;
 	if (use_pse)
-- 
1.7.9.5


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