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>
diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index 8adb6b5..cea11c8 100644
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -391,43 +391,12 @@
#endif
};
-typedef pte_t make_pte_t(pteval_t);
-typedef pmd_t make_pmd_t(pmdval_t);
-typedef pud_t make_pud_t(pudval_t);
-typedef pgd_t make_pgd_t(pgdval_t);
-
-typedef pteval_t pte_val_t(pte_t);
-typedef pmdval_t pmd_val_t(pmd_t);
-typedef pudval_t pud_val_t(pud_t);
-typedef pgdval_t pgd_val_t(pgd_t);
-
-
#if defined(CONFIG_X86_32) && !defined(CONFIG_X86_PAE)
/* 32-bit pagetable entries */
-#define paravirt_native_make_pte (make_pte_t *)_paravirt_ident_32
-#define paravirt_native_pte_val (pte_val_t *)_paravirt_ident_32
-
-#define paravirt_native_make_pmd (make_pmd_t *)_paravirt_ident_32
-#define paravirt_native_pmd_val (pmd_val_t *)_paravirt_ident_32
-
-#define paravirt_native_make_pud (make_pud_t *)_paravirt_ident_32
-#define paravirt_native_pud_val (pud_val_t *)_paravirt_ident_32
-
-#define paravirt_native_make_pgd (make_pgd_t *)_paravirt_ident_32
-#define paravirt_native_pgd_val (pgd_val_t *)_paravirt_ident_32
+#define PTE_IDENT __PV_IS_CALLEE_SAVE(_paravirt_ident_32)
#else
/* 64-bit pagetable entries */
-#define paravirt_native_make_pte (make_pte_t *)_paravirt_ident_64
-#define paravirt_native_pte_val (pte_val_t *)_paravirt_ident_64
-
-#define paravirt_native_make_pmd (make_pmd_t *)_paravirt_ident_64
-#define paravirt_native_pmd_val (pmd_val_t *)_paravirt_ident_64
-
-#define paravirt_native_make_pud (make_pud_t *)_paravirt_ident_64
-#define paravirt_native_pud_val (pud_val_t *)_paravirt_ident_64
-
-#define paravirt_native_make_pgd (make_pgd_t *)_paravirt_ident_64
-#define paravirt_native_pgd_val (pgd_val_t *)_paravirt_ident_64
+#define PTE_IDENT __PV_IS_CALLEE_SAVE(_paravirt_ident_64)
#endif
struct pv_mmu_ops pv_mmu_ops = {
@@ -481,21 +450,23 @@
.pmd_clear = native_pmd_clear,
#endif
.set_pud = native_set_pud,
- .pmd_val = paravirt_native_pmd_val,
- .make_pmd = paravirt_native_make_pmd,
+
+ .pmd_val = PTE_IDENT,
+ .make_pmd = PTE_IDENT,
#if PAGETABLE_LEVELS == 4
- .pud_val = paravirt_native_pud_val,
- .make_pud = paravirt_native_make_pud,
+ .pud_val = PTE_IDENT,
+ .make_pud = PTE_IDENT,
+
.set_pgd = native_set_pgd,
#endif
#endif /* PAGETABLE_LEVELS >= 3 */
- .pte_val = paravirt_native_pte_val,
- .pgd_val = paravirt_native_pgd_val,
+ .pte_val = PTE_IDENT,
+ .pgd_val = PTE_IDENT,
- .make_pte = paravirt_native_make_pte,
- .make_pgd = paravirt_native_make_pgd,
+ .make_pte = PTE_IDENT,
+ .make_pgd = PTE_IDENT,
.dup_mmap = paravirt_nop,
.exit_mmap = paravirt_nop,