diff options
Diffstat (limited to 'arch/x86/mm')
| -rw-r--r-- | arch/x86/mm/tlb.c | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c index 06116480c343..d548b98e5a49 100644 --- a/arch/x86/mm/tlb.c +++ b/arch/x86/mm/tlb.c @@ -23,6 +23,7 @@ #else # define STATIC_NOPV static # define __flush_tlb_local native_flush_tlb_local +# define __flush_tlb_global native_flush_tlb_global #endif /* @@ -891,6 +892,46 @@ unsigned long __get_current_cr3_fast(void) EXPORT_SYMBOL_GPL(__get_current_cr3_fast); /* + * Flush everything + */ +STATIC_NOPV void native_flush_tlb_global(void) +{ + unsigned long cr4, flags; + + if (static_cpu_has(X86_FEATURE_INVPCID)) { + /* + * Using INVPCID is considerably faster than a pair of writes + * to CR4 sandwiched inside an IRQ flag save/restore. + * + * Note, this works with CR4.PCIDE=0 or 1. + */ + invpcid_flush_all(); + return; + } + + /* + * Read-modify-write to CR4 - protect it from preemption and + * from interrupts. (Use the raw variant because this code can + * be called from deep inside debugging code.) + */ + raw_local_irq_save(flags); + + cr4 = this_cpu_read(cpu_tlbstate.cr4); + /* toggle PGE */ + native_write_cr4(cr4 ^ X86_CR4_PGE); + /* write old PGE again and flush TLBs */ + native_write_cr4(cr4); + + raw_local_irq_restore(flags); +} + +void flush_tlb_global(void) +{ + __flush_tlb_global(); +} +EXPORT_SYMBOL_GPL(flush_tlb_global); + +/* * Flush the entire current user mapping */ STATIC_NOPV void native_flush_tlb_local(void) |