From: Dave Hansen In preparation to adding additional PCID flushing, abstract the loading of a new ASID into CR3. [ Peterz: Split out from big combo patch ] Signed-off-by: Dave Hansen Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Thomas Gleixner --- arch/x86/mm/tlb.c | 22 ++++++++++++++++++++-- 1 file changed, 20 insertions(+), 2 deletions(-) --- a/arch/x86/mm/tlb.c +++ b/arch/x86/mm/tlb.c @@ -100,6 +100,24 @@ static void choose_new_asid(struct mm_st *need_flush = true; } +static void load_new_mm_cr3(pgd_t *pgdir, u16 new_asid, bool need_flush) +{ + unsigned long new_mm_cr3; + + if (need_flush) { + new_mm_cr3 = build_cr3(pgdir, new_asid); + } else { + new_mm_cr3 = build_cr3_noflush(pgdir, new_asid); + } + + /* + * Caution: many callers of this function expect + * that load_cr3() is serializing and orders TLB + * fills with respect to the mm_cpumask writes. + */ + write_cr3(new_mm_cr3); +} + void leave_mm(int cpu) { struct mm_struct *loaded_mm = this_cpu_read(cpu_tlbstate.loaded_mm); @@ -230,7 +248,7 @@ void switch_mm_irqs_off(struct mm_struct if (need_flush) { this_cpu_write(cpu_tlbstate.ctxs[new_asid].ctx_id, next->context.ctx_id); this_cpu_write(cpu_tlbstate.ctxs[new_asid].tlb_gen, next_tlb_gen); - write_cr3(build_cr3(next->pgd, new_asid)); + load_new_mm_cr3(next->pgd, new_asid, true); /* * NB: This gets called via leave_mm() in the idle path @@ -243,7 +261,7 @@ void switch_mm_irqs_off(struct mm_struct trace_tlb_flush_rcuidle(TLB_FLUSH_ON_TASK_SWITCH, TLB_FLUSH_ALL); } else { /* The new ASID is already up to date. */ - write_cr3(build_cr3_noflush(next->pgd, new_asid)); + load_new_mm_cr3(next->pgd, new_asid, false); /* See above wrt _rcuidle. */ trace_tlb_flush_rcuidle(TLB_FLUSH_ON_TASK_SWITCH, 0);