Remove duplicated code for reading control registers From: Glauber de Oliveira Costa On Tue, Mar 13, 2007 at 05:33:09AM -0700, Randy.Dunlap wrote: > On Tue, 13 Mar 2007, Glauber de Oliveira Costa wrote: > > > 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. > > missing patch..... > thanks. Attached now -- Glauber de Oliveira Costa Red Hat Inc. "Free as in Freedom" Signed-off-by: Andi Kleen --- include/asm-x86_64/system.h | 7 ++++++- include/asm-x86_64/tlbflush.h | 33 +++++---------------------------- 2 files changed, 11 insertions(+), 29 deletions(-) 2d19cf472903fa4c9e763301b7b1cc0fa53bd023 Index: linux/include/asm-x86_64/system.h =================================================================== --- linux.orig/include/asm-x86_64/system.h +++ linux/include/asm-x86_64/system.h @@ -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()) Index: linux/include/asm-x86_64/tlbflush.h =================================================================== --- linux.orig/include/asm-x86_64/tlbflush.h +++ linux/include/asm-x86_64/tlbflush.h @@ -3,41 +3,18 @@ #include #include - -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 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) \