[PATCH] i386: PARAVIRT: drop unused ptep_get_and_clear

In shadow mode hypervisors, ptep_get_and_clear achieves the desired
purpose of keeping the shadows in sync by issuing a native_get_and_clear,
followed by a call to pte_update, which indicates the PTE has been
modified.

Direct mode hypervisors (Xen) have no need for this anyway, and will trap
the update using writable pagetables.

This means no hypervisor makes use of ptep_get_and_clear; there is no
reason to have it in the paravirt-ops structure.  Change confusing
terminology about raw vs. native functions into consistent use of
native_pte_xxx for operations which do not invoke paravirt-ops.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andi Kleen <ak@suse.de>

diff --git a/arch/i386/kernel/paravirt.c b/arch/i386/kernel/paravirt.c
index 596f382c641ce0f5cb59f9e5182019a36b35c505..c4850ddd6a9d26d313752d04662dae5c2ead0ee1 100644 (file)
--- a/arch/i386/kernel/paravirt.c
+++ b/arch/i386/kernel/paravirt.c
@@ -315,8 +315,6 @@ struct paravirt_ops paravirt_ops = {
        .pte_update = paravirt_nop,
        .pte_update_defer = paravirt_nop,
 
-       .ptep_get_and_clear = native_ptep_get_and_clear,
-
 #ifdef CONFIG_HIGHPTE
        .kmap_atomic_pte = kmap_atomic,
 #endif

diff --git a/include/asm-i386/paravirt.h b/include/asm-i386/paravirt.h
index 2ba18963e114e881c8559921308dfbc739dc442e..e2e7f98723c57fac6c3f45c797a1a7a1060df45a 100644 (file)
--- a/include/asm-i386/paravirt.h
+++ b/include/asm-i386/paravirt.h
@@ -188,8 +188,6 @@ struct paravirt_ops
        void (*pte_update_defer)(struct mm_struct *mm,
                                 unsigned long addr, pte_t *ptep);
 
-       pte_t (*ptep_get_and_clear)(pte_t *ptep);
-
 #ifdef CONFIG_HIGHPTE
        void *(*kmap_atomic_pte)(struct page *page, enum km_type type);
 #endif
@@ -859,12 +857,8 @@ static inline void pmd_clear(pmd_t *pmdp)
        PVOP_VCALL1(pmd_clear, pmdp);
 }
 
-static inline pte_t raw_ptep_get_and_clear(pte_t *p)
-{
-       unsigned long long val = PVOP_CALL1(unsigned long long, ptep_get_and_clear, p);
-       return (pte_t) { val, val >> 32 };
-}
 #else  /* !CONFIG_X86_PAE */
+
 static inline pte_t __pte(unsigned long val)
 {
        return (pte_t) { PVOP_CALL1(unsigned long, make_pte, val) };
@@ -900,11 +894,6 @@ static inline void set_pmd(pmd_t *pmdp, pmd_t pmdval)
 {
        PVOP_VCALL2(set_pmd, pmdp, pmdval.pud.pgd.pgd);
 }
-
-static inline pte_t raw_ptep_get_and_clear(pte_t *p)
-{
-       return (pte_t) { PVOP_CALL1(unsigned long, ptep_get_and_clear, p) };
-}
 #endif /* CONFIG_X86_PAE */
 
 #define  __HAVE_ARCH_ENTER_LAZY_CPU_MODE

diff --git a/include/asm-i386/pgtable.h b/include/asm-i386/pgtable.h
index befc697821e59f9490db1e1369651aab53f90d57..e7ddd2341309782ad67541707ff668c274e93d7e 100644 (file)
--- a/include/asm-i386/pgtable.h
+++ b/include/asm-i386/pgtable.h
@@ -267,8 +267,6 @@ extern void vmalloc_sync_all(void);
  */
 #define pte_update(mm, addr, ptep)             do { } while (0)
 #define pte_update_defer(mm, addr, ptep)       do { } while (0)
-
-#define raw_ptep_get_and_clear(xp)     native_ptep_get_and_clear(xp)
 #endif
 
 /*
@@ -335,7 +333,7 @@ do {                                                                        \
 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
 static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
 {
-       pte_t pte = raw_ptep_get_and_clear(ptep);
+       pte_t pte = native_ptep_get_and_clear(ptep);
        pte_update(mm, addr, ptep);
        return pte;
 }