Subject: [PATCH v2 1/4] powerpc/mm: update ptep_set_access_flag to not do full mm tlb flush

From: "Aneesh Kumar K.V" <[email-masked]>
Date: Mon, 14 Nov 2016 20:41:25 +0530

When we are updating pte, we just need to flush the tlb mapping for
that pte. Right now we do a full mm flush because we don't track page
size. Update the interface to track the page size and use that to
do the right tlb flush.

Signed-off-by: Aneesh Kumar K.V <[email-masked]>
---
 arch/powerpc/include/asm/book3s/32/pgtable.h |  4 +++-
 arch/powerpc/include/asm/book3s/64/pgtable.h |  7 +++++--
 arch/powerpc/include/asm/book3s/64/radix.h   | 14 +++++++-------
 arch/powerpc/include/asm/nohash/32/pgtable.h |  4 +++-
 arch/powerpc/include/asm/nohash/64/pgtable.h |  4 +++-
 arch/powerpc/mm/pgtable-book3s64.c           |  3 ++-
 arch/powerpc/mm/pgtable-radix.c              | 16 ++++++++++++++++
 arch/powerpc/mm/pgtable.c                    | 10 ++++++++--
 arch/powerpc/mm/tlb-radix.c                  | 15 ---------------
 9 files changed, 47 insertions(+), 30 deletions(-)

diff --git a/arch/powerpc/include/asm/book3s/32/pgtable.h b/arch/powerpc/include/asm/book3s/32/pgtable.h
index 6b8b2d57fdc8..0713626e9189 100644
--- a/arch/powerpc/include/asm/book3s/32/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/32/pgtable.h
@@ -224,7 +224,9 @@ static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,

 static inline void __ptep_set_access_flags(struct mm_struct *mm,
-					   pte_t *ptep, pte_t entry)
+					   pte_t *ptep, pte_t entry,
+					   unsigned long address,
+					   unsigned long pg_sz)
 {
 	unsigned long set = pte_val(entry) &
 		(_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW | _PAGE_EXEC);
diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
index 86870c11917b..46d739457d68 100644
--- a/arch/powerpc/include/asm/book3s/64/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
@@ -580,10 +580,13 @@ static inline bool check_pte_access(unsigned long access, unsigned long ptev)
  */
 
 static inline void __ptep_set_access_flags(struct mm_struct *mm,
-					   pte_t *ptep, pte_t entry)
+					   pte_t *ptep, pte_t entry,
+					   unsigned long address,
+					   unsigned long pg_sz)
 {
 	if (radix_enabled())
-		return radix__ptep_set_access_flags(mm, ptep, entry);
+		return radix__ptep_set_access_flags(mm, ptep, entry,
+						    address, pg_sz);
 	return hash__ptep_set_access_flags(ptep, entry);
 }
 
diff --git a/arch/powerpc/include/asm/book3s/64/radix.h b/arch/powerpc/include/asm/book3s/64/radix.h
index 2a46dea8e1b1..279b2f68e00f 100644
--- a/arch/powerpc/include/asm/book3s/64/radix.h
+++ b/arch/powerpc/include/asm/book3s/64/radix.h
@@ -110,6 +110,7 @@
 #define RADIX_PUD_TABLE_SIZE	(sizeof(pud_t) << RADIX_PUD_INDEX_SIZE)
 #define RADIX_PGD_TABLE_SIZE	(sizeof(pgd_t) << RADIX_PGD_INDEX_SIZE)
 
+extern int radix_get_mmu_psize(unsigned long pg_sz);
 static inline unsigned long __radix_pte_update(pte_t *ptep, unsigned long clr,
 					       unsigned long set)
 {
@@ -167,7 +168,9 @@ static inline unsigned long radix__pte_update(struct mm_struct *mm,
  * function doesn't need to invalidate tlb.
  */
 static inline void radix__ptep_set_access_flags(struct mm_struct *mm,
-						pte_t *ptep, pte_t entry)
+						pte_t *ptep, pte_t entry,
+						unsigned long address,
+						unsigned long pg_sz)
 {
 
 	unsigned long set = pte_val(entry) & (_PAGE_DIRTY | _PAGE_ACCESSED |
@@ -175,6 +178,7 @@ static inline void radix__ptep_set_access_flags(struct mm_struct *mm,
 
 	if (cpu_has_feature(CPU_FTR_POWER9_DD1)) {
 
+		int psize;
 		unsigned long old_pte, new_pte;
 
 		old_pte = __radix_pte_update(ptep, ~0, 0);
@@ -183,12 +187,8 @@ static inline void radix__ptep_set_access_flags(struct mm_struct *mm,
 		 * new value of pte
 		 */
 		new_pte = old_pte | set;
-
-		/*
-		 * For now let's do heavy pid flush
-		 * radix__flush_tlb_page_psize(mm, addr, mmu_virtual_psize);
-		 */
-		radix__flush_tlb_mm(mm);
+		psize = radix_get_mmu_psize(pg_sz);
+		radix__flush_tlb_page_psize(mm, address, psize);
 
 		__radix_pte_update(ptep, 0, new_pte);
 	} else
diff --git a/arch/powerpc/include/asm/nohash/32/pgtable.h b/arch/powerpc/include/asm/nohash/32/pgtable.h
index c219ef7be53b..24ee66bf7223 100644
--- a/arch/powerpc/include/asm/nohash/32/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/32/pgtable.h
@@ -268,7 +268,9 @@ static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,

 static inline void __ptep_set_access_flags(struct mm_struct *mm,
-					   pte_t *ptep, pte_t entry)
+					   pte_t *ptep, pte_t entry,
+					   unsigned long address,
+					   unsigned long pg_sz)
 {
 	unsigned long set = pte_val(entry) &
 		(_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW | _PAGE_EXEC);
diff --git a/arch/powerpc/include/asm/nohash/64/pgtable.h b/arch/powerpc/include/asm/nohash/64/pgtable.h
index 653a1838469d..86d49dc60ec6 100644
--- a/arch/powerpc/include/asm/nohash/64/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/64/pgtable.h
@@ -301,7 +301,9 @@ static inline void pte_clear(struct mm_struct *mm, unsigned long addr,
  * function doesn't need to flush the hash entry
  */
 static inline void __ptep_set_access_flags(struct mm_struct *mm,
-					   pte_t *ptep, pte_t entry)
+					   pte_t *ptep, pte_t entry,
+					   unsigned long address,
+					   unsigned long pg_sz)
 {
 	unsigned long bits = pte_val(entry) &
 		(_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW | _PAGE_EXEC);
diff --git a/arch/powerpc/mm/pgtable-book3s64.c b/arch/powerpc/mm/pgtable-book3s64.c
index f4f437cbabf1..5c7c501b7cae 100644
--- a/arch/powerpc/mm/pgtable-book3s64.c
+++ b/arch/powerpc/mm/pgtable-book3s64.c
@@ -35,7 +35,8 @@ int pmdp_set_access_flags(struct vm_area_struct *vma, unsigned long address,
 #endif
 	changed = !pmd_same(*(pmdp), entry);
 	if (changed) {
-		__ptep_set_access_flags(vma->vm_mm, pmdp_ptep(pmdp), pmd_pte(entry));
+		__ptep_set_access_flags(vma->vm_mm, pmdp_ptep(pmdp), pmd_pte(entry),
+					address, HPAGE_PMD_SIZE);
 		flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
 	}
 	return changed;
diff --git a/arch/powerpc/mm/pgtable-radix.c b/arch/powerpc/mm/pgtable-radix.c
index ed7bddc456b7..6b1ffc449158 100644
--- a/arch/powerpc/mm/pgtable-radix.c
+++ b/arch/powerpc/mm/pgtable-radix.c
@@ -222,6 +222,22 @@ static int __init get_idx_from_shift(unsigned int shift)
 	return idx;
 }
 
+int radix_get_mmu_psize(unsigned long page_size)
+{
+	int psize;
+
+	if (page_size == (1UL << mmu_psize_defs[mmu_virtual_psize].shift))
+		psize = mmu_virtual_psize;
+	else if (page_size == (1UL << mmu_psize_defs[MMU_PAGE_2M].shift))
+		psize = MMU_PAGE_2M;
+	else if (page_size == (1UL << mmu_psize_defs[MMU_PAGE_1G].shift))
+		psize = MMU_PAGE_1G;
+	else
+		return -1;
+	return psize;
+}
+
+
 static int __init radix_dt_scan_page_sizes(unsigned long node,
 					   const char *uname, int depth,
 					   void *data)
diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c
index 911fdfb63ec1..a9ec0d8f1bcf 100644
--- a/arch/powerpc/mm/pgtable.c
+++ b/arch/powerpc/mm/pgtable.c
@@ -219,12 +219,18 @@ int ptep_set_access_flags(struct vm_area_struct *vma, unsigned long address,
 			  pte_t *ptep, pte_t entry, int dirty)
 {
 	int changed;
+	unsigned long pg_sz;
+
 	entry = set_access_flags_filter(entry, vma, dirty);
 	changed = !pte_same(*(ptep), entry);
 	if (changed) {
-		if (!is_vm_hugetlb_page(vma))
+		if (!is_vm_hugetlb_page(vma)) {
+			pg_sz = PAGE_SIZE;
 			assert_pte_locked(vma->vm_mm, address);
-		__ptep_set_access_flags(vma->vm_mm, ptep, entry);
+		} else
+			pg_sz = huge_page_size(hstate_vma(vma));
+		__ptep_set_access_flags(vma->vm_mm, ptep, entry,
+					address, pg_sz);
 		flush_tlb_page(vma, address);
 	}
 	return changed;
diff --git a/arch/powerpc/mm/tlb-radix.c b/arch/powerpc/mm/tlb-radix.c
index 0e49ec541ab5..0b923c37cd30 100644
--- a/arch/powerpc/mm/tlb-radix.c
+++ b/arch/powerpc/mm/tlb-radix.c
@@ -278,21 +278,6 @@ void radix__flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
 }
 EXPORT_SYMBOL(radix__flush_tlb_range);
 
-static int radix_get_mmu_psize(int page_size)
-{
-	int psize;
-
-	if (page_size == (1UL << mmu_psize_defs[mmu_virtual_psize].shift))
-		psize = mmu_virtual_psize;
-	else if (page_size == (1UL << mmu_psize_defs[MMU_PAGE_2M].shift))
-		psize = MMU_PAGE_2M;
-	else if (page_size == (1UL << mmu_psize_defs[MMU_PAGE_1G].shift))
-		psize = MMU_PAGE_1G;
-	else
-		return -1;
-	return psize;
-}
-
 void radix__tlb_flush(struct mmu_gather *tlb)
 {
 	int psize = 0;
-- 
2.10.2