[PATCH] x86/mm: drop unused argument sync_global_pgds()

[PATCH] x86/mm: drop unused argument sync_global_pgds()

[Kirill A. Shutemov]

There's no users that wants sync_global_pgd(.remove=1) sinc af2cf278ef4f
("x86/mm/hotplug: Don't remove PGD entries in remove_pagetable()").

Let's drop 'remove'.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
---
 arch/x86/include/asm/pgtable_64.h |  3 +--
 arch/x86/mm/fault.c               |  2 +-
 arch/x86/mm/init_64.c             | 25 ++++++-------------------
 3 files changed, 8 insertions(+), 22 deletions(-)

diff --git a/arch/x86/include/asm/pgtable_64.h b/arch/x86/include/asm/pgtable_64.h
index 1cc82ece9ac1..62b775926045 100644
--- a/arch/x86/include/asm/pgtable_64.h
+++ b/arch/x86/include/asm/pgtable_64.h
@@ -116,8 +116,7 @@ static inline void native_pgd_clear(pgd_t *pgd)
 	native_set_pgd(pgd, native_make_pgd(0));
 }
 
-extern void sync_global_pgds(unsigned long start, unsigned long end,
-			     int removed);
+extern void sync_global_pgds(unsigned long start, unsigned long end);
 
 /*
  * Conversion functions: convert a page and protection to a page entry,
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index dc8023060456..7e316a0e7fc9 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -413,7 +413,7 @@ out:
 
 void vmalloc_sync_all(void)
 {
-	sync_global_pgds(VMALLOC_START & PGDIR_MASK, VMALLOC_END, 0);
+	sync_global_pgds(VMALLOC_START & PGDIR_MASK, VMALLOC_END);
 }
 
 /*
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 14b9dd71d9e8..164a478fd349 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -89,10 +89,10 @@ static int __init nonx32_setup(char *str)
 __setup("noexec32=", nonx32_setup);
 
 /*
- * When memory was added/removed make sure all the processes MM have
+ * When memory was added make sure all the processes MM have
  * suitable PGD entries in the local PGD level page.
  */
-void sync_global_pgds(unsigned long start, unsigned long end, int removed)
+void sync_global_pgds(unsigned long start, unsigned long end)
 {
 	unsigned long address;
 
@@ -100,14 +100,6 @@ void sync_global_pgds(unsigned long start, unsigned long end, int removed)
 		const pgd_t *pgd_ref = pgd_offset_k(address);
 		struct page *page;
 
-		/*
-		 * When it is called after memory hot remove, pgd_none()
-		 * returns true. In this case (removed == 1), we must clear
-		 * the PGD entries in the local PGD level page.
-		 */
-		if (pgd_none(*pgd_ref) && !removed)
-			continue;
-
 		spin_lock(&pgd_lock);
 		list_for_each_entry(page, &pgd_list, lru) {
 			pgd_t *pgd;
@@ -122,13 +114,8 @@ void sync_global_pgds(unsigned long start, unsigned long end, int removed)
 				BUG_ON(pgd_page_vaddr(*pgd)
 				       != pgd_page_vaddr(*pgd_ref));
 
-			if (removed) {
-				if (pgd_none(*pgd_ref) && !pgd_none(*pgd))
-					pgd_clear(pgd);
-			} else {
-				if (pgd_none(*pgd))
-					set_pgd(pgd, *pgd_ref);
-			}
+                        if (pgd_none(*pgd))
+                            set_pgd(pgd, *pgd_ref);
 
 			spin_unlock(pgt_lock);
 		}
@@ -596,7 +583,7 @@ kernel_physical_mapping_init(unsigned long paddr_start,
 	}
 
 	if (pgd_changed)
-		sync_global_pgds(vaddr_start, vaddr_end - 1, 0);
+		sync_global_pgds(vaddr_start, vaddr_end - 1);
 
 	__flush_tlb_all();
 
@@ -1239,7 +1226,7 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
 	} else
 		err = vmemmap_populate_basepages(start, end, node);
 	if (!err)
-		sync_global_pgds(start, end - 1, 0);
+		sync_global_pgds(start, end - 1);
 	return err;
 }
 
-- 
2.10.2

Re: [PATCH] x86/mm: drop unused argument sync_global_pgds()

[Thomas Gleixner]

On Mon, 12 Dec 2016, Kirill A. Shutemov wrote:

> There's no users that wants sync_global_pgd(.remove=1) sinc af2cf278ef4f
> ("x86/mm/hotplug: Don't remove PGD entries in remove_pagetable()").
> 
> Let's drop 'remove'.

The argument is named 'removed' ....

>  /*
> - * When memory was added/removed make sure all the processes MM have
> + * When memory was added make sure all the processes MM have
>   * suitable PGD entries in the local PGD level page.
>   */
> -void sync_global_pgds(unsigned long start, unsigned long end, int removed)
> +void sync_global_pgds(unsigned long start, unsigned long end)
>  {
>  	unsigned long address;
>  
> @@ -100,14 +100,6 @@ void sync_global_pgds(unsigned long start, unsigned long end, int removed)
>  		const pgd_t *pgd_ref = pgd_offset_k(address);
>  		struct page *page;
>  
> -		/*
> -		 * When it is called after memory hot remove, pgd_none()
> -		 * returns true. In this case (removed == 1), we must clear
> -		 * the PGD entries in the local PGD level page.
> -		 */
> -		if (pgd_none(*pgd_ref) && !removed)
> -			continue;
> -

Errm. This continues, when pgd_none(*pgd_ref) is true AND removed is false,
i.e. that is NOT the removed == true case which you are aiming to drop.

> +                        if (pgd_none(*pgd))
> +                            set_pgd(pgd, *pgd_ref);

This is whitespace damaged in several ways.

Thanks,

	tglx

[PATCHv2] x86/mm: drop unused argument sync_global_pgds()

[Kirill A. Shutemov]

There's no users that want sync_global_pgd(.remove=1) since af2cf278ef4f
("x86/mm/hotplug: Don't remove PGD entries in remove_pagetable()").

Let's drop 'removed'.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
---
 arch/x86/include/asm/pgtable_64.h |  3 +--
 arch/x86/mm/fault.c               |  2 +-
 arch/x86/mm/init_64.c             | 24 +++++++-----------------
 3 files changed, 9 insertions(+), 20 deletions(-)

diff --git a/arch/x86/include/asm/pgtable_64.h b/arch/x86/include/asm/pgtable_64.h
index 1cc82ece9ac1..62b775926045 100644
--- a/arch/x86/include/asm/pgtable_64.h
+++ b/arch/x86/include/asm/pgtable_64.h
@@ -116,8 +116,7 @@ static inline void native_pgd_clear(pgd_t *pgd)
 	native_set_pgd(pgd, native_make_pgd(0));
 }
 
-extern void sync_global_pgds(unsigned long start, unsigned long end,
-			     int removed);
+extern void sync_global_pgds(unsigned long start, unsigned long end);
 
 /*
  * Conversion functions: convert a page and protection to a page entry,
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index dc8023060456..7e316a0e7fc9 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -413,7 +413,7 @@ out:
 
 void vmalloc_sync_all(void)
 {
-	sync_global_pgds(VMALLOC_START & PGDIR_MASK, VMALLOC_END, 0);
+	sync_global_pgds(VMALLOC_START & PGDIR_MASK, VMALLOC_END);
 }
 
 /*
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 14b9dd71d9e8..963895f9af7f 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -89,10 +89,10 @@ static int __init nonx32_setup(char *str)
 __setup("noexec32=", nonx32_setup);
 
 /*
- * When memory was added/removed make sure all the processes MM have
+ * When memory was added make sure all the processes MM have
  * suitable PGD entries in the local PGD level page.
  */
-void sync_global_pgds(unsigned long start, unsigned long end, int removed)
+void sync_global_pgds(unsigned long start, unsigned long end)
 {
 	unsigned long address;
 
@@ -100,12 +100,7 @@ void sync_global_pgds(unsigned long start, unsigned long end, int removed)
 		const pgd_t *pgd_ref = pgd_offset_k(address);
 		struct page *page;
 
-		/*
-		 * When it is called after memory hot remove, pgd_none()
-		 * returns true. In this case (removed == 1), we must clear
-		 * the PGD entries in the local PGD level page.
-		 */
-		if (pgd_none(*pgd_ref) && !removed)
+		if (pgd_none(*pgd_ref))
 			continue;
 
 		spin_lock(&pgd_lock);
@@ -122,13 +117,8 @@ void sync_global_pgds(unsigned long start, unsigned long end, int removed)
 				BUG_ON(pgd_page_vaddr(*pgd)
 				       != pgd_page_vaddr(*pgd_ref));
 
-			if (removed) {
-				if (pgd_none(*pgd_ref) && !pgd_none(*pgd))
-					pgd_clear(pgd);
-			} else {
-				if (pgd_none(*pgd))
-					set_pgd(pgd, *pgd_ref);
-			}
+			if (pgd_none(*pgd))
+				set_pgd(pgd, *pgd_ref);
 
 			spin_unlock(pgt_lock);
 		}
@@ -596,7 +586,7 @@ kernel_physical_mapping_init(unsigned long paddr_start,
 	}
 
 	if (pgd_changed)
-		sync_global_pgds(vaddr_start, vaddr_end - 1, 0);
+		sync_global_pgds(vaddr_start, vaddr_end - 1);
 
 	__flush_tlb_all();
 
@@ -1239,7 +1229,7 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
 	} else
 		err = vmemmap_populate_basepages(start, end, node);
 	if (!err)
-		sync_global_pgds(start, end - 1, 0);
+		sync_global_pgds(start, end - 1);
 	return err;
 }
 
-- 
2.10.2

[tip:x86/urgent] x86/mm: Drop unused argument 'removed' from sync_global_pgds()

[tip-bot for Kirill A. Shutemov]

Commit-ID:  5372e155a28f56122eb10db56d4130f481a89cd7
Gitweb:     http://git.kernel.org/tip/5372e155a28f56122eb10db56d4130f481a89cd7
Author:     Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
AuthorDate: Thu, 15 Dec 2016 02:44:03 +0300
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Thu, 15 Dec 2016 12:46:07 +0100

x86/mm: Drop unused argument 'removed' from sync_global_pgds()

Since commit af2cf278ef4f ("x86/mm/hotplug: Don't remove PGD entries in
remove_pagetable()") there are no callers of sync_global_pgds() which set
the 'removed' argument to 1.

Remove the argument and the related conditionals in the function.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Link: http://lkml.kernel.org/r/20161214234403.137556-1-kirill.shutemov@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

---
 arch/x86/include/asm/pgtable_64.h |  3 +--
 arch/x86/mm/fault.c               |  2 +-
 arch/x86/mm/init_64.c             | 24 +++++++-----------------
 3 files changed, 9 insertions(+), 20 deletions(-)

diff --git a/arch/x86/include/asm/pgtable_64.h b/arch/x86/include/asm/pgtable_64.h
index 1cc82ec..62b77592 100644
--- a/arch/x86/include/asm/pgtable_64.h
+++ b/arch/x86/include/asm/pgtable_64.h
@@ -116,8 +116,7 @@ static inline void native_pgd_clear(pgd_t *pgd)
 	native_set_pgd(pgd, native_make_pgd(0));
 }
 
-extern void sync_global_pgds(unsigned long start, unsigned long end,
-			     int removed);
+extern void sync_global_pgds(unsigned long start, unsigned long end);
 
 /*
  * Conversion functions: convert a page and protection to a page entry,
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 17c55a5..e3254ca 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -413,7 +413,7 @@ out:
 
 void vmalloc_sync_all(void)
 {
-	sync_global_pgds(VMALLOC_START & PGDIR_MASK, VMALLOC_END, 0);
+	sync_global_pgds(VMALLOC_START & PGDIR_MASK, VMALLOC_END);
 }
 
 /*
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 14b9dd7..963895f 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -89,10 +89,10 @@ static int __init nonx32_setup(char *str)
 __setup("noexec32=", nonx32_setup);
 
 /*
- * When memory was added/removed make sure all the processes MM have
+ * When memory was added make sure all the processes MM have
  * suitable PGD entries in the local PGD level page.
  */
-void sync_global_pgds(unsigned long start, unsigned long end, int removed)
+void sync_global_pgds(unsigned long start, unsigned long end)
 {
 	unsigned long address;
 
@@ -100,12 +100,7 @@ void sync_global_pgds(unsigned long start, unsigned long end, int removed)
 		const pgd_t *pgd_ref = pgd_offset_k(address);
 		struct page *page;
 
-		/*
-		 * When it is called after memory hot remove, pgd_none()
-		 * returns true. In this case (removed == 1), we must clear
-		 * the PGD entries in the local PGD level page.
-		 */
-		if (pgd_none(*pgd_ref) && !removed)
+		if (pgd_none(*pgd_ref))
 			continue;
 
 		spin_lock(&pgd_lock);
@@ -122,13 +117,8 @@ void sync_global_pgds(unsigned long start, unsigned long end, int removed)
 				BUG_ON(pgd_page_vaddr(*pgd)
 				       != pgd_page_vaddr(*pgd_ref));
 
-			if (removed) {
-				if (pgd_none(*pgd_ref) && !pgd_none(*pgd))
-					pgd_clear(pgd);
-			} else {
-				if (pgd_none(*pgd))
-					set_pgd(pgd, *pgd_ref);
-			}
+			if (pgd_none(*pgd))
+				set_pgd(pgd, *pgd_ref);
 
 			spin_unlock(pgt_lock);
 		}
@@ -596,7 +586,7 @@ kernel_physical_mapping_init(unsigned long paddr_start,
 	}
 
 	if (pgd_changed)
-		sync_global_pgds(vaddr_start, vaddr_end - 1, 0);
+		sync_global_pgds(vaddr_start, vaddr_end - 1);
 
 	__flush_tlb_all();
 
@@ -1239,7 +1229,7 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
 	} else
 		err = vmemmap_populate_basepages(start, end, node);
 	if (!err)
-		sync_global_pgds(start, end - 1, 0);
+		sync_global_pgds(start, end - 1);
 	return err;
 }