diff options
| -rw-r--r-- | arch/x86/xen/mmu_pv.c | 24 |
1 files changed, 17 insertions, 7 deletions
diff --git a/arch/x86/xen/mmu_pv.c b/arch/x86/xen/mmu_pv.c index d2d6980c66b3..7b366e252e03 100644 --- a/arch/x86/xen/mmu_pv.c +++ b/arch/x86/xen/mmu_pv.c @@ -1194,6 +1194,13 @@ static void __init xen_pagetable_p2m_setup(void) static void __init xen_pagetable_init(void) { + /* + * The majority of further PTE writes is to pagetables already + * announced as such to Xen. Hence it is more efficient to use + * hypercalls for these updates. + */ + pv_ops.mmu.set_pte = __xen_set_pte; + paging_init(); xen_post_allocator_init(); @@ -1423,10 +1430,18 @@ static void xen_pgd_free(struct mm_struct *mm, pgd_t *pgd) * * Many of these PTE updates are done on unpinned and writable pages * and doing a hypercall for these is unnecessary and expensive. At - * this point it is not possible to tell if a page is pinned or not, - * so always write the PTE directly and rely on Xen trapping and + * this point it is rarely possible to tell if a page is pinned, so + * mostly write the PTE directly and rely on Xen trapping and * emulating any updates as necessary. */ +static void __init xen_set_pte_init(pte_t *ptep, pte_t pte) +{ + if (unlikely(is_early_ioremap_ptep(ptep))) + __xen_set_pte(ptep, pte); + else + native_set_pte(ptep, pte); +} + __visible pte_t xen_make_pte_init(pteval_t pte) { unsigned long pfn; @@ -1448,11 +1463,6 @@ __visible pte_t xen_make_pte_init(pteval_t pte) } PV_CALLEE_SAVE_REGS_THUNK(xen_make_pte_init); -static void __init xen_set_pte_init(pte_t *ptep, pte_t pte) -{ - __xen_set_pte(ptep, pte); -} - /* Early in boot, while setting up the initial pagetable, assume everything is pinned. */ static void __init xen_alloc_pte_init(struct mm_struct *mm, unsigned long pfn) |