xen: condense everything onto xen_set_pte
xen_set_pte_at and xen_clear_pte are essentially identical to
xen_set_pte, so just make them all common.
When batched set_pte and pte_clear are the same, but the unbatch operation
must be different: they need to update the two halves of the pte in
different order.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index fb3e92e..11d7ef0 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -108,12 +108,6 @@
u32 prot_commit;
u32 prot_commit_batched;
-
- u32 set_pte_at;
- u32 set_pte_at_batched;
- u32 set_pte_at_pinned;
- u32 set_pte_at_current;
- u32 set_pte_at_kernel;
} mmu_stats;
static u8 zero_stats;
@@ -334,26 +328,37 @@
set_pte_vaddr(vaddr, mfn_pte(mfn, flags));
}
+static bool xen_batched_set_pte(pte_t *ptep, pte_t pteval)
+{
+ struct mmu_update u;
+
+ if (paravirt_get_lazy_mode() != PARAVIRT_LAZY_MMU)
+ return false;
+
+ xen_mc_batch();
+
+ u.ptr = virt_to_machine(ptep).maddr | MMU_NORMAL_PT_UPDATE;
+ u.val = pte_val_ma(pteval);
+ xen_extend_mmu_update(&u);
+
+ xen_mc_issue(PARAVIRT_LAZY_MMU);
+
+ return true;
+}
+
+void xen_set_pte(pte_t *ptep, pte_t pteval)
+{
+ ADD_STATS(pte_update, 1);
+// ADD_STATS(pte_update_pinned, xen_page_pinned(ptep));
+
+ if (!xen_batched_set_pte(ptep, pteval))
+ native_set_pte(ptep, pteval);
+}
+
void xen_set_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t pteval)
{
- ADD_STATS(set_pte_at, 1);
-// ADD_STATS(set_pte_at_pinned, xen_page_pinned(ptep));
- ADD_STATS(set_pte_at_current, mm == current->mm);
- ADD_STATS(set_pte_at_kernel, mm == &init_mm);
-
- if(paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU) {
- struct mmu_update u;
-
- xen_mc_batch();
-
- u.ptr = virt_to_machine(ptep).maddr | MMU_NORMAL_PT_UPDATE;
- u.val = pte_val_ma(pteval);
- xen_extend_mmu_update(&u);
-
- xen_mc_issue(PARAVIRT_LAZY_MMU);
- } else
- native_set_pte(ptep, pteval);
+ xen_set_pte(ptep, pteval);
}
pte_t xen_ptep_modify_prot_start(struct mm_struct *mm,
@@ -611,21 +616,6 @@
xen_set_pud_hyper(ptr, val);
}
-void xen_set_pte(pte_t *ptep, pte_t pte)
-{
- ADD_STATS(pte_update, 1);
-// ADD_STATS(pte_update_pinned, xen_page_pinned(ptep));
- ADD_STATS(pte_update_batched, paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU);
-
-#ifdef CONFIG_X86_PAE
- ptep->pte_high = pte.pte_high;
- smp_wmb();
- ptep->pte_low = pte.pte_low;
-#else
- *ptep = pte;
-#endif
-}
-
#ifdef CONFIG_X86_PAE
void xen_set_pte_atomic(pte_t *ptep, pte_t pte)
{
@@ -634,9 +624,8 @@
void xen_pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
- ptep->pte_low = 0;
- smp_wmb(); /* make sure low gets written first */
- ptep->pte_high = 0;
+ if (!xen_batched_set_pte(ptep, native_make_pte(0)))
+ native_pte_clear(mm, addr, ptep);
}
void xen_pmd_clear(pmd_t *pmdp)
@@ -2452,14 +2441,6 @@
xen_debugfs_create_u32_array("mmu_update_histo", 0444, d_mmu_debug,
mmu_stats.mmu_update_histo, 20);
- debugfs_create_u32("set_pte_at", 0444, d_mmu_debug, &mmu_stats.set_pte_at);
- debugfs_create_u32("set_pte_at_batched", 0444, d_mmu_debug,
- &mmu_stats.set_pte_at_batched);
- debugfs_create_u32("set_pte_at_current", 0444, d_mmu_debug,
- &mmu_stats.set_pte_at_current);
- debugfs_create_u32("set_pte_at_kernel", 0444, d_mmu_debug,
- &mmu_stats.set_pte_at_kernel);
-
debugfs_create_u32("prot_commit", 0444, d_mmu_debug, &mmu_stats.prot_commit);
debugfs_create_u32("prot_commit_batched", 0444, d_mmu_debug,
&mmu_stats.prot_commit_batched);