From 0c3292ca8025c5aef44dc389ac3a6bf4a325e0be Mon Sep 17 00:00:00 2001 From: Nadav Amit Date: Fri, 24 Nov 2017 19:29:06 -0800 Subject: [PATCH] x86/tlb: Refactor CR4 setting and shadow write Refactor the write to CR4 and its shadow value. This is done in preparation for the addition of an assertion to check that IRQs are disabled during CR4 update. No functional change. Signed-off-by: Nadav Amit Signed-off-by: Thomas Gleixner Cc: nadav.amit@gmail.com Cc: Andy Lutomirski Cc: linux-edac@vger.kernel.org Link: https://lkml.kernel.org/r/20171125032907.2241-2-namit@vmware.com --- arch/x86/include/asm/tlbflush.h | 24 +++++++++++------------- 1 file changed, 11 insertions(+), 13 deletions(-) diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h index 509046cfa5ce..e736f7f0ba92 100644 --- a/arch/x86/include/asm/tlbflush.h +++ b/arch/x86/include/asm/tlbflush.h @@ -173,17 +173,20 @@ static inline void cr4_init_shadow(void) this_cpu_write(cpu_tlbstate.cr4, __read_cr4()); } +static inline void __cr4_set(unsigned long cr4) +{ + this_cpu_write(cpu_tlbstate.cr4, cr4); + __write_cr4(cr4); +} + /* Set in this cpu's CR4. */ static inline void cr4_set_bits(unsigned long mask) { unsigned long cr4; cr4 = this_cpu_read(cpu_tlbstate.cr4); - if ((cr4 | mask) != cr4) { - cr4 |= mask; - this_cpu_write(cpu_tlbstate.cr4, cr4); - __write_cr4(cr4); - } + if ((cr4 | mask) != cr4) + __cr4_set(cr4 | mask); } /* Clear in this cpu's CR4. */ @@ -192,11 +195,8 @@ static inline void cr4_clear_bits(unsigned long mask) unsigned long cr4; cr4 = this_cpu_read(cpu_tlbstate.cr4); - if ((cr4 & ~mask) != cr4) { - cr4 &= ~mask; - this_cpu_write(cpu_tlbstate.cr4, cr4); - __write_cr4(cr4); - } + if ((cr4 & ~mask) != cr4) + __cr4_set(cr4 & ~mask); } static inline void cr4_toggle_bits(unsigned long mask) @@ -204,9 +204,7 @@ static inline void cr4_toggle_bits(unsigned long mask) unsigned long cr4; cr4 = this_cpu_read(cpu_tlbstate.cr4); - cr4 ^= mask; - this_cpu_write(cpu_tlbstate.cr4, cr4); - __write_cr4(cr4); + __cr4_set(cr4 ^ mask); } /* Read the CR4 shadow. */ -- 2.45.2