page fault scalability patch V10: [7/7] s/390 atomic pte operations

Christoph Lameter
2004-10-15T19:08:22Z

Changelog
* Provide atomic pte operations for s390

Signed-off-by: Christoph Lameter <clameter@sgi.com>

Index: linux-2.6.9-rc4/include/asm-s390/pgtable.h
=================================--- linux-2.6.9-rc4.orig/include/asm-s390/pgtable.h 2004-10-10 19:58:24.000000000 -0700
+++ linux-2.6.9-rc4/include/asm-s390/pgtable.h 2004-10-14 12:22:14.000000000 -0700
@@ -567,6 +567,17 @@
return pte;
}

+#define ptep_xchg_flush(__vma, __address, __ptep, __pteval) \
+({ \
+ struct mm_struct *__mm = __vma->vm_mm; \
+ pte_t __pte; \
+ spin_lock(&__mm->page_table_lock); \
+ __pte = ptep_clear_flush(__vma, __address, __ptep); \
+ set_pte(__ptep, __pteval); \
+ spin_unlock(&__mm->page_table_lock); \
+ __pte; \
+})
+
static inline void ptep_set_wrprotect(pte_t *ptep)
{
pte_t old_pte = *ptep;
@@ -778,6 +789,19 @@

#define kern_addr_valid(addr) (1)

+/* Atomic PTE operations */
+#define __HAVE_ARCH_ATOMIC_TABLE_OPS
+
+static inline pte_t ptep_xchg(struct mm_struct *mm, unsigned long address, pte_t *ptep, pte_t pteval)
+{
+ return __pte(xchg(ptep, pte_val(pteval)));
+}
+
+static inline int ptep_cmpxchg (struct mm_struct *mm, unsigned long address, pte_t *ptep, pte_t oldval, pte_t newval)
+{
+ return cmpxchg(ptep, pte_val(oldval), pte_val(newval)) = pte_val(oldval);
+}
+
/*
* No page table caches to initialise
*/
@@ -791,6 +815,7 @@
#define __HAVE_ARCH_PTEP_CLEAR_DIRTY_FLUSH
#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
#define __HAVE_ARCH_PTEP_CLEAR_FLUSH
+#define __HAVE_ARCH_PTEP_XCHG_FLUSH
#define __HAVE_ARCH_PTEP_SET_WRPROTECT
#define __HAVE_ARCH_PTEP_MKDIRTY
#define __HAVE_ARCH_PTE_SAME
Index: linux-2.6.9-rc4/include/asm-s390/pgalloc.h
=================================--- linux-2.6.9-rc4.orig/include/asm-s390/pgalloc.h 2004-10-10 19:58:06.000000000 -0700
+++ linux-2.6.9-rc4/include/asm-s390/pgalloc.h 2004-10-14 12:22:14.000000000 -0700
@@ -97,6 +97,10 @@
pgd_val(*pgd) = _PGD_ENTRY | __pa(pmd);
}

+static inline int pgd_test_and_populate(struct mm_struct *mm, pdg_t *pgd, pmd_t *pmd)
+{
+ return cmpxchg(pgd, _PAGE_TABLE_INV, _PGD_ENTRY | __pa(pmd)) = _PAGE_TABLE_INV;
+}
#endif /* __s390x__ */

static inline void
@@ -119,6 +123,18 @@
pmd_populate_kernel(mm, pmd, (pte_t *)((page-mem_map) << PAGE_SHIFT));
}

+static inline int
+pmd_test_and_populate(struct mm_struct *mm, pmd_t *pmd, struct page *page)
+{
+ int rc;
+ spin_lock(&mm->page_table_lock);
+
+ rc=pte_same(*pmd, _PAGE_INVALID_EMPTY);
+ if (rc) pmd_populate(mm, pmd, page);
+ spin_unlock(&mm->page_table_lock);
+ return rc;
+}
+
/*
* page table entry allocation/free routines.
*/