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Remove duplicated code for reading control registers

PATCH In review Glauber de Oliveira Costa 1 participant 2 messages Mar 13, 2007 1 message not in the archive

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Glauber de Oliveira Costa

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#0 lore raw

PATCH 1/1 Remove duplicated code for reading control registers

Tiny cleanup:

In x86_64, the same functions for reading cr3 and writing cr{3,4} are defined in tlbflush.h and system.h, whith just a name change. The only difference is the clobbering of memory, which seems a safe, and even needed change for the write_cr4. This patch removes the duplicate. write_cr3() is moved to system.h for consistency.

Signed-off-by Glauber de Oliveira Costa <[email protected]>
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Glauber de Oliveira Costa
Red Hat Inc.
"Free as in Freedom"

A message that is not in the archive (sent off-list or not yet received): [email protected]

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#2 lore raw
Quoted 4 lines · Randy.Dunlap
Quoted 2 lines · Glauber de Oliveira Costa

Tiny cleanup:

Quoted 8 lines
Quoted 5 lines

In x86_64, the same functions for reading cr3 and writing cr{3,4} are defined in tlbflush.h and system.h, whith just a name change. The only difference is the clobbering of memory, which seems a safe, and even needed change for the write_cr4. This patch removes the duplicate. write_cr3() is moved to system.h for consistency.

missing patch.....

thanks. Attached now

Signature · 3 lines
Glauber de Oliveira Costa
Red Hat Inc.
"Free as in Freedom"

---

 include/asm-x86_64/system.h   |    7 ++++++-
 include/asm-x86_64/tlbflush.h |   33 +++++----------------------------
 2 files changed, 11 insertions(+), 29 deletions(-)

2d19cf472903fa4c9e763301b7b1cc0fa53bd023

include/asm-x86_64/system.h +6 -1
index bd376bc..91b461d 100644
@@ -89,6 +89,11 @@ static inline unsigned long read_cr3(voi
 	return cr3;
 } 
 
+static inline void write_cr3(unsigned long val)
+{ 
+	asm volatile("movq %0,%%cr3" :: "r" (val) : "memory");
+} 
+
 static inline unsigned long read_cr4(void)
 { 
 	unsigned long cr4;

@@ -98,7 +103,7 @@ static inline unsigned long read_cr4(voi
 
 static inline void write_cr4(unsigned long val)
 { 
-	asm volatile("movq %0,%%cr4" :: "r" (val));
+	asm volatile("movq %0,%%cr4" :: "r" (val) : "memory");
 } 
 
 #define stts() write_cr0(8 | read_cr0())
include/asm-x86_64/tlbflush.h +5 -28
index 983bd29..512401b 100644
@@ -3,41 +3,18 @@
 
 #include <linux/mm.h>
 #include <asm/processor.h>
-
-static inline unsigned long get_cr3(void)
-{
-	unsigned long cr3;
-	asm volatile("mov %%cr3,%0" : "=r" (cr3));
-	return cr3;
-}
-
-static inline void set_cr3(unsigned long cr3)
-{
-	asm volatile("mov %0,%%cr3" :: "r" (cr3) : "memory");
-}
+#include <asm/system.h>
 
 static inline void __flush_tlb(void)
 {
-	set_cr3(get_cr3());
-}
-
-static inline unsigned long get_cr4(void)
-{
-	unsigned long cr4;
-	asm volatile("mov %%cr4,%0" : "=r" (cr4));
-	return cr4;
-}
-
-static inline void set_cr4(unsigned long cr4)
-{
-	asm volatile("mov %0,%%cr4" :: "r" (cr4) : "memory");
+	write_cr3(read_cr3());
 }
 
 static inline void __flush_tlb_all(void)
 {
-	unsigned long cr4 = get_cr4();
-	set_cr4(cr4 & ~X86_CR4_PGE);	/* clear PGE */
-	set_cr4(cr4);			/* write old PGE again and flush TLBs */
+	unsigned long cr4 = read_cr4();
+	write_cr4(cr4 & ~X86_CR4_PGE);	/* clear PGE */
+	write_cr4(cr4);			/* write old PGE again and flush TLBs */
 }
 
 #define __flush_tlb_one(addr) \
Signature · 1 line
1.1.3