x86/paravirt: use callee-saved convention for pte_val/make_pte/etc

Impact: Optimization

In the native case, pte_val, make_pte, etc are all just identity
functions, so there's no need to clobber a lot of registers over them.

(This changes the 32-bit callee-save calling convention to return both
EAX and EDX so functions can return 64-bit values.)

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

1 files changed, 39 insertions, 39 deletions

diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index beb10ecdbe67..2d098b78bc10 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -19,7 +19,7 @@
 #define CLBR_ANY  ((1 << 4) - 1)
 
 #define CLBR_ARG_REGS   (CLBR_EAX | CLBR_EDX | CLBR_ECX)
-#define CLBR_RET_REG    (CLBR_EAX)
+#define CLBR_RET_REG    (CLBR_EAX | CLBR_EDX)
 #define CLBR_SCRATCH    (0)
 #else
 #define CLBR_RAX  CLBR_EAX
@@ -308,11 +308,11 @@ struct pv_mmu_ops {
         void (*ptep_modify_prot_commit)(struct mm_struct *mm, unsigned long addr,
                                         pte_t *ptep, pte_t pte);
 
-        pteval_t (*pte_val)(pte_t);
-        pte_t (*make_pte)(pteval_t pte);
+        struct paravirt_callee_save pte_val;
+        struct paravirt_callee_save make_pte;
 
-        pgdval_t (*pgd_val)(pgd_t);
-        pgd_t (*make_pgd)(pgdval_t pgd);
+        struct paravirt_callee_save pgd_val;
+        struct paravirt_callee_save make_pgd;
 
 #if PAGETABLE_LEVELS >= 3
 #ifdef CONFIG_X86_PAE
@@ -327,12 +327,12 @@ struct pv_mmu_ops {
 
         void (*set_pud)(pud_t *pudp, pud_t pudval);
 
-        pmdval_t (*pmd_val)(pmd_t);
-        pmd_t (*make_pmd)(pmdval_t pmd);
+        struct paravirt_callee_save pmd_val;
+        struct paravirt_callee_save make_pmd;
 
 #if PAGETABLE_LEVELS == 4
-        pudval_t (*pud_val)(pud_t);
-        pud_t (*make_pud)(pudval_t pud);
+        struct paravirt_callee_save pud_val;
+        struct paravirt_callee_save make_pud;
 
         void (*set_pgd)(pgd_t *pudp, pgd_t pgdval);
 #endif  /* PAGETABLE_LEVELS == 4 */
@@ -1155,13 +1155,13 @@ static inline pte_t __pte(pteval_t val)
         pteval_t ret;
 
         if (sizeof(pteval_t) > sizeof(long))
-                ret = PVOP_CALL2(pteval_t,
-                                 pv_mmu_ops.make_pte,
-                                 val, (u64)val >> 32);
+                ret = PVOP_CALLEE2(pteval_t,
+                                   pv_mmu_ops.make_pte,
+                                   val, (u64)val >> 32);
         else
-                ret = PVOP_CALL1(pteval_t,
-                                 pv_mmu_ops.make_pte,
-                                 val);
+                ret = PVOP_CALLEE1(pteval_t,
+                                   pv_mmu_ops.make_pte,
+                                   val);
 
         return (pte_t) { .pte = ret };
 }
@@ -1171,11 +1171,11 @@ static inline pteval_t pte_val(pte_t pte)
         pteval_t ret;
 
         if (sizeof(pteval_t) > sizeof(long))
-                ret = PVOP_CALL2(pteval_t, pv_mmu_ops.pte_val,
-                                 pte.pte, (u64)pte.pte >> 32);
+                ret = PVOP_CALLEE2(pteval_t, pv_mmu_ops.pte_val,
+                                   pte.pte, (u64)pte.pte >> 32);
         else
-                ret = PVOP_CALL1(pteval_t, pv_mmu_ops.pte_val,
-                                 pte.pte);
+                ret = PVOP_CALLEE1(pteval_t, pv_mmu_ops.pte_val,
+                                   pte.pte);
 
         return ret;
 }
@@ -1185,11 +1185,11 @@ static inline pgd_t __pgd(pgdval_t val)
         pgdval_t ret;
 
         if (sizeof(pgdval_t) > sizeof(long))
-                ret = PVOP_CALL2(pgdval_t, pv_mmu_ops.make_pgd,
-                                 val, (u64)val >> 32);
+                ret = PVOP_CALLEE2(pgdval_t, pv_mmu_ops.make_pgd,
+                                   val, (u64)val >> 32);
         else
-                ret = PVOP_CALL1(pgdval_t, pv_mmu_ops.make_pgd,
-                                 val);
+                ret = PVOP_CALLEE1(pgdval_t, pv_mmu_ops.make_pgd,
+                                   val);
 
         return (pgd_t) { ret };
 }
@@ -1199,11 +1199,11 @@ static inline pgdval_t pgd_val(pgd_t pgd)
         pgdval_t ret;
 
         if (sizeof(pgdval_t) > sizeof(long))
-                ret =  PVOP_CALL2(pgdval_t, pv_mmu_ops.pgd_val,
-                                  pgd.pgd, (u64)pgd.pgd >> 32);
+                ret =  PVOP_CALLEE2(pgdval_t, pv_mmu_ops.pgd_val,
+                                    pgd.pgd, (u64)pgd.pgd >> 32);
         else
-                ret =  PVOP_CALL1(pgdval_t, pv_mmu_ops.pgd_val,
-                                  pgd.pgd);
+                ret =  PVOP_CALLEE1(pgdval_t, pv_mmu_ops.pgd_val,
+                                    pgd.pgd);
 
         return ret;
 }
@@ -1267,11 +1267,11 @@ static inline pmd_t __pmd(pmdval_t val)
         pmdval_t ret;
 
         if (sizeof(pmdval_t) > sizeof(long))
-                ret = PVOP_CALL2(pmdval_t, pv_mmu_ops.make_pmd,
-                                 val, (u64)val >> 32);
+                ret = PVOP_CALLEE2(pmdval_t, pv_mmu_ops.make_pmd,
+                                   val, (u64)val >> 32);
         else
-                ret = PVOP_CALL1(pmdval_t, pv_mmu_ops.make_pmd,
-                                 val);
+                ret = PVOP_CALLEE1(pmdval_t, pv_mmu_ops.make_pmd,
+                                   val);
 
         return (pmd_t) { ret };
 }
@@ -1281,11 +1281,11 @@ static inline pmdval_t pmd_val(pmd_t pmd)
         pmdval_t ret;
 
         if (sizeof(pmdval_t) > sizeof(long))
-                ret =  PVOP_CALL2(pmdval_t, pv_mmu_ops.pmd_val,
-                                  pmd.pmd, (u64)pmd.pmd >> 32);
+                ret =  PVOP_CALLEE2(pmdval_t, pv_mmu_ops.pmd_val,
+                                    pmd.pmd, (u64)pmd.pmd >> 32);
         else
-                ret =  PVOP_CALL1(pmdval_t, pv_mmu_ops.pmd_val,
-                                  pmd.pmd);
+                ret =  PVOP_CALLEE1(pmdval_t, pv_mmu_ops.pmd_val,
+                                    pmd.pmd);
 
         return ret;
 }
@@ -1307,11 +1307,11 @@ static inline pud_t __pud(pudval_t val)
         pudval_t ret;
 
         if (sizeof(pudval_t) > sizeof(long))
-                ret = PVOP_CALL2(pudval_t, pv_mmu_ops.make_pud,
-                                 val, (u64)val >> 32);
+                ret = PVOP_CALLEE2(pudval_t, pv_mmu_ops.make_pud,
+                                   val, (u64)val >> 32);
         else
-                ret = PVOP_CALL1(pudval_t, pv_mmu_ops.make_pud,
-                                 val);
+                ret = PVOP_CALLEE1(pudval_t, pv_mmu_ops.make_pud,
+                                   val);
 
         return (pud_t) { ret };
 }