diff options
Diffstat (limited to 'arch/x86/include/asm/tlbflush.h')
| -rw-r--r-- | arch/x86/include/asm/tlbflush.h | 21 |
1 files changed, 16 insertions, 5 deletions
diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h index 511bf5fae8b8..6690cd3fc8b1 100644 --- a/arch/x86/include/asm/tlbflush.h +++ b/arch/x86/include/asm/tlbflush.h @@ -148,6 +148,22 @@ static inline unsigned long build_cr3_noflush(pgd_t *pgd, u16 asid) #define __flush_tlb_one_user(addr) __native_flush_tlb_one_user(addr) #endif +static inline bool tlb_defer_switch_to_init_mm(void) +{ + /* + * If we have PCID, then switching to init_mm is reasonably + * fast. If we don't have PCID, then switching to init_mm is + * quite slow, so we try to defer it in the hopes that we can + * avoid it entirely. The latter approach runs the risk of + * receiving otherwise unnecessary IPIs. + * + * This choice is just a heuristic. The tlb code can handle this + * function returning true or false regardless of whether we have + * PCID. + */ + return !static_cpu_has(X86_FEATURE_PCID); +} + struct tlb_context { u64 ctx_id; u64 tlb_gen; @@ -538,9 +554,4 @@ extern void arch_tlbbatch_flush(struct arch_tlbflush_unmap_batch *batch); native_flush_tlb_others(mask, info) #endif -extern void tlb_flush_remove_tables(struct mm_struct *mm); -extern void tlb_flush_remove_tables_local(void *arg); - -#define HAVE_TLB_FLUSH_REMOVE_TABLES - #endif /* _ASM_X86_TLBFLUSH_H */ |