arm, thp: remove infrastructure for handling splitting PMDs
With new refcounting we don't need to mark PMDs splitting. Let's drop
code to handle this.
pmdp_splitting_flush() is not needed too: on splitting PMD we will do
pmdp_clear_flush() + set_pte_at(). pmdp_clear_flush() will do IPI as
needed for fast_gup.
[arnd@arndb.de: fix unterminated ifdef in header file]
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h
index a745a2a..59d1457 100644
--- a/arch/arm/include/asm/pgtable-3level.h
+++ b/arch/arm/include/asm/pgtable-3level.h
@@ -88,7 +88,6 @@
#define L_PMD_SECT_VALID (_AT(pmdval_t, 1) << 0)
#define L_PMD_SECT_DIRTY (_AT(pmdval_t, 1) << 55)
-#define L_PMD_SECT_SPLITTING (_AT(pmdval_t, 1) << 56)
#define L_PMD_SECT_NONE (_AT(pmdval_t, 1) << 57)
#define L_PMD_SECT_RDONLY (_AT(pteval_t, 1) << 58)
@@ -232,13 +231,6 @@
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
#define pmd_trans_huge(pmd) (pmd_val(pmd) && !pmd_table(pmd))
-#define pmd_trans_splitting(pmd) (pmd_isset((pmd), L_PMD_SECT_SPLITTING))
-
-#ifdef CONFIG_HAVE_RCU_TABLE_FREE
-#define __HAVE_ARCH_PMDP_SPLITTING_FLUSH
-void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address,
- pmd_t *pmdp);
-#endif
#endif
#define PMD_BIT_FUNC(fn,op) \
@@ -246,7 +238,6 @@
PMD_BIT_FUNC(wrprotect, |= L_PMD_SECT_RDONLY);
PMD_BIT_FUNC(mkold, &= ~PMD_SECT_AF);
-PMD_BIT_FUNC(mksplitting, |= L_PMD_SECT_SPLITTING);
PMD_BIT_FUNC(mkwrite, &= ~L_PMD_SECT_RDONLY);
PMD_BIT_FUNC(mkdirty, |= L_PMD_SECT_DIRTY);
PMD_BIT_FUNC(mkyoung, |= PMD_SECT_AF);
diff --git a/arch/arm/lib/uaccess_with_memcpy.c b/arch/arm/lib/uaccess_with_memcpy.c
index 588bbc2..6bd1089 100644
--- a/arch/arm/lib/uaccess_with_memcpy.c
+++ b/arch/arm/lib/uaccess_with_memcpy.c
@@ -52,14 +52,13 @@
*
* Lock the page table for the destination and check
* to see that it's still huge and whether or not we will
- * need to fault on write, or if we have a splitting THP.
+ * need to fault on write.
*/
if (unlikely(pmd_thp_or_huge(*pmd))) {
ptl = ¤t->mm->page_table_lock;
spin_lock(ptl);
if (unlikely(!pmd_thp_or_huge(*pmd)
- || pmd_hugewillfault(*pmd)
- || pmd_trans_splitting(*pmd))) {
+ || pmd_hugewillfault(*pmd))) {
spin_unlock(ptl);
return 0;
}
diff --git a/arch/arm/mm/flush.c b/arch/arm/mm/flush.c
index 1ec8e75..c2acebb 100644
--- a/arch/arm/mm/flush.c
+++ b/arch/arm/mm/flush.c
@@ -415,18 +415,3 @@
*/
__cpuc_flush_dcache_area(page_address(page), PAGE_SIZE);
}
-
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-#ifdef CONFIG_HAVE_RCU_TABLE_FREE
-void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address,
- pmd_t *pmdp)
-{
- pmd_t pmd = pmd_mksplitting(*pmdp);
- VM_BUG_ON(address & ~PMD_MASK);
- set_pmd_at(vma->vm_mm, address, pmdp, pmd);
-
- /* dummy IPI to serialise against fast_gup */
- kick_all_cpus_sync();
-}
-#endif /* CONFIG_HAVE_RCU_TABLE_FREE */
-#endif /* CONFIG_TRANSPARENT_HUGEPAGE */