[v2,08/13] mm: page_alloc: split out DEBUG_PAGEALLOC

Message ID 20230516063821.121844-9-wangkefeng.wang@huawei.com
State New
Headers
Series mm: page_alloc: misc cleanup and refector |

Commit Message

Kefeng Wang May 16, 2023, 6:38 a.m. UTC
  Move DEBUG_PAGEALLOC related functions into a single file to
reduce a bit of page_alloc.c.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
---
 include/linux/mm.h    | 76 ++++++++++++++++++++++++++++---------------
 mm/Makefile           |  1 +
 mm/debug_page_alloc.c | 59 +++++++++++++++++++++++++++++++++
 mm/page_alloc.c       | 69 ---------------------------------------
 4 files changed, 109 insertions(+), 96 deletions(-)
 create mode 100644 mm/debug_page_alloc.c
  

Comments

Andrew Morton May 16, 2023, 10:22 p.m. UTC | #1
On Tue, 16 May 2023 14:38:16 +0800 Kefeng Wang <wangkefeng.wang@huawei.com> wrote:

> DEBUG_PAGEALLOC
>
>  mm/debug_page_alloc.c | 59 +++++++++++++++++++++++++++++++++
>  mm/page_alloc.c       | 69 ---------------------------------------

and

FAIL_PAGE_ALLOC

We're irritatingly inconsistent about whether there's an underscore.

akpm:/usr/src/25> grep page_alloc mm/*c|wc -l
49
akpm:/usr/src/25> grep pagealloc mm/*c|wc -l 
28
  
Kefeng Wang May 18, 2023, 1:35 a.m. UTC | #2
On 2023/5/17 6:22, Andrew Morton wrote:
> On Tue, 16 May 2023 14:38:16 +0800 Kefeng Wang <wangkefeng.wang@huawei.com> wrote:
> 
>> DEBUG_PAGEALLOC
>>
>>   mm/debug_page_alloc.c | 59 +++++++++++++++++++++++++++++++++
>>   mm/page_alloc.c       | 69 ---------------------------------------
> 
> and
> 
> FAIL_PAGE_ALLOC
> 
> We're irritatingly inconsistent about whether there's an underscore.
> 
> akpm:/usr/src/25> grep page_alloc mm/*c|wc -l
> 49
> akpm:/usr/src/25> grep pagealloc mm/*c|wc -l
> 28

All the 28 pagealloc naming is from DEBUG_PAGEALLOC feature, they chould
be changed to page_alloc except the cmdline, but it will lead to long
function name and don't gain too much advantage, so keep unchange?

$ grep pagealloc mm/*c
mm/debug_page_alloc.c:bool _debug_pagealloc_enabled_early __read_mostly
mm/debug_page_alloc.c:EXPORT_SYMBOL(_debug_pagealloc_enabled_early);
mm/debug_page_alloc.c:DEFINE_STATIC_KEY_FALSE(_debug_pagealloc_enabled);
mm/debug_page_alloc.c:EXPORT_SYMBOL(_debug_pagealloc_enabled);
mm/debug_page_alloc.c:static int __init early_debug_pagealloc(char *buf)
mm/debug_page_alloc.c:	return kstrtobool(buf, 
&_debug_pagealloc_enabled_early);
mm/debug_page_alloc.c:early_param("debug_pagealloc", early_debug_pagealloc);
mm/memory_hotplug.c:	 * Freeing the page with debug_pagealloc enabled 
will try to unmap it,
mm/memory_hotplug.c:	debug_pagealloc_map_pages(page, 1 << order);
mm/mm_init.c:	      debug_pagealloc_enabled())) {
mm/mm_init.c:	if (debug_pagealloc_enabled()) {
mm/mm_init.c:		static_branch_enable(&_debug_pagealloc_enabled);
mm/page_alloc.c:	 * page becomes unavailable via debug_pagealloc or 
arch_free_page.
mm/page_alloc.c:	debug_pagealloc_unmap_pages(page, 1 << order);
mm/page_alloc.c:	debug_pagealloc_map_pages(page, 1 << order);
mm/page_poison.c:		pr_err("pagealloc: single bit error\n");
mm/page_poison.c:		pr_err("pagealloc: memory corruption\n");
mm/page_poison.c:	dump_page(page, "pagealloc: corrupted page details");
mm/slab.c:static inline bool is_debug_pagealloc_cache(struct kmem_cache 
*cachep)
mm/slab.c:	return debug_pagealloc_enabled_static() && OFF_SLAB(cachep) &&
mm/slab.c:	if (!is_debug_pagealloc_cache(cachep))
mm/slab.c:	if (is_debug_pagealloc_cache(cachep))
mm/slab.c:	 * To activate debug pagealloc, off-slab management is necessary
mm/slab.c:	if (debug_pagealloc_enabled_static() && (flags & SLAB_POISON) &&
mm/slab.c:		is_debug_pagealloc_cache(cachep))
mm/slub.c:	if (!debug_pagealloc_enabled_static())
mm/vmalloc.c:	if (debug_pagealloc_enabled_static())
mm/vmalloc.c:	if (debug_pagealloc_enabled_static())



>
  
Andrew Morton May 18, 2023, 2:10 a.m. UTC | #3
On Thu, 18 May 2023 09:35:29 +0800 Kefeng Wang <wangkefeng.wang@huawei.com> wrote:

> > We're irritatingly inconsistent about whether there's an underscore.
> > 
> > akpm:/usr/src/25> grep page_alloc mm/*c|wc -l
> > 49
> > akpm:/usr/src/25> grep pagealloc mm/*c|wc -l
> > 28
> 
> All the 28 pagealloc naming is from DEBUG_PAGEALLOC feature, they chould
> be changed to page_alloc except the cmdline, but it will lead to long
> function name and don't gain too much advantage, so keep unchange?

Sure, it's probably not the worst thing in there.  I was just having
a moan.
  

Patch

diff --git a/include/linux/mm.h b/include/linux/mm.h
index db3f66ed2f32..d3241f4ac903 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -3485,9 +3485,58 @@  static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages)
 	if (debug_pagealloc_enabled_static())
 		__kernel_map_pages(page, numpages, 0);
 }
+
+extern unsigned int _debug_guardpage_minorder;
+DECLARE_STATIC_KEY_FALSE(_debug_guardpage_enabled);
+
+static inline unsigned int debug_guardpage_minorder(void)
+{
+	return _debug_guardpage_minorder;
+}
+
+static inline bool debug_guardpage_enabled(void)
+{
+	return static_branch_unlikely(&_debug_guardpage_enabled);
+}
+
+static inline bool page_is_guard(struct page *page)
+{
+	if (!debug_guardpage_enabled())
+		return false;
+
+	return PageGuard(page);
+}
+
+bool __set_page_guard(struct zone *zone, struct page *page, unsigned int order,
+		      int migratetype);
+static inline bool set_page_guard(struct zone *zone, struct page *page,
+				  unsigned int order, int migratetype)
+{
+	if (!debug_guardpage_enabled())
+		return false;
+	return __set_page_guard(zone, page, order, migratetype);
+}
+
+void __clear_page_guard(struct zone *zone, struct page *page, unsigned int order,
+			int migratetype);
+static inline void clear_page_guard(struct zone *zone, struct page *page,
+				    unsigned int order, int migratetype)
+{
+	if (!debug_guardpage_enabled())
+		return;
+	__clear_page_guard(zone, page, order, migratetype);
+}
+
 #else	/* CONFIG_DEBUG_PAGEALLOC */
 static inline void debug_pagealloc_map_pages(struct page *page, int numpages) {}
 static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages) {}
+static inline unsigned int debug_guardpage_minorder(void) { return 0; }
+static inline bool debug_guardpage_enabled(void) { return false; }
+static inline bool page_is_guard(struct page *page) { return false; }
+static inline bool set_page_guard(struct zone *zone, struct page *page,
+			unsigned int order, int migratetype) { return false; }
+static inline void clear_page_guard(struct zone *zone, struct page *page,
+				unsigned int order, int migratetype) {}
 #endif	/* CONFIG_DEBUG_PAGEALLOC */
 
 #ifdef __HAVE_ARCH_GATE_AREA
@@ -3725,33 +3774,6 @@  static inline bool vma_is_special_huge(const struct vm_area_struct *vma)
 
 #endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLBFS */
 
-#ifdef CONFIG_DEBUG_PAGEALLOC
-extern unsigned int _debug_guardpage_minorder;
-DECLARE_STATIC_KEY_FALSE(_debug_guardpage_enabled);
-
-static inline unsigned int debug_guardpage_minorder(void)
-{
-	return _debug_guardpage_minorder;
-}
-
-static inline bool debug_guardpage_enabled(void)
-{
-	return static_branch_unlikely(&_debug_guardpage_enabled);
-}
-
-static inline bool page_is_guard(struct page *page)
-{
-	if (!debug_guardpage_enabled())
-		return false;
-
-	return PageGuard(page);
-}
-#else
-static inline unsigned int debug_guardpage_minorder(void) { return 0; }
-static inline bool debug_guardpage_enabled(void) { return false; }
-static inline bool page_is_guard(struct page *page) { return false; }
-#endif /* CONFIG_DEBUG_PAGEALLOC */
-
 #if MAX_NUMNODES > 1
 void __init setup_nr_node_ids(void);
 #else
diff --git a/mm/Makefile b/mm/Makefile
index 0eec4bc72d3f..678530a07326 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -124,6 +124,7 @@  obj-$(CONFIG_SECRETMEM) += secretmem.o
 obj-$(CONFIG_CMA_SYSFS) += cma_sysfs.o
 obj-$(CONFIG_USERFAULTFD) += userfaultfd.o
 obj-$(CONFIG_IDLE_PAGE_TRACKING) += page_idle.o
+obj-$(CONFIG_DEBUG_PAGEALLOC) += debug_page_alloc.o
 obj-$(CONFIG_DEBUG_PAGE_REF) += debug_page_ref.o
 obj-$(CONFIG_DAMON) += damon/
 obj-$(CONFIG_HARDENED_USERCOPY) += usercopy.o
diff --git a/mm/debug_page_alloc.c b/mm/debug_page_alloc.c
new file mode 100644
index 000000000000..f9d145730fd1
--- /dev/null
+++ b/mm/debug_page_alloc.c
@@ -0,0 +1,59 @@ 
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/mm.h>
+#include <linux/page-isolation.h>
+
+unsigned int _debug_guardpage_minorder;
+
+bool _debug_pagealloc_enabled_early __read_mostly
+			= IS_ENABLED(CONFIG_DEBUG_PAGEALLOC_ENABLE_DEFAULT);
+EXPORT_SYMBOL(_debug_pagealloc_enabled_early);
+DEFINE_STATIC_KEY_FALSE(_debug_pagealloc_enabled);
+EXPORT_SYMBOL(_debug_pagealloc_enabled);
+
+DEFINE_STATIC_KEY_FALSE(_debug_guardpage_enabled);
+
+static int __init early_debug_pagealloc(char *buf)
+{
+	return kstrtobool(buf, &_debug_pagealloc_enabled_early);
+}
+early_param("debug_pagealloc", early_debug_pagealloc);
+
+static int __init debug_guardpage_minorder_setup(char *buf)
+{
+	unsigned long res;
+
+	if (kstrtoul(buf, 10, &res) < 0 ||  res > MAX_ORDER / 2) {
+		pr_err("Bad debug_guardpage_minorder value\n");
+		return 0;
+	}
+	_debug_guardpage_minorder = res;
+	pr_info("Setting debug_guardpage_minorder to %lu\n", res);
+	return 0;
+}
+early_param("debug_guardpage_minorder", debug_guardpage_minorder_setup);
+
+bool __set_page_guard(struct zone *zone, struct page *page, unsigned int order,
+		      int migratetype)
+{
+	if (order >= debug_guardpage_minorder())
+		return false;
+
+	__SetPageGuard(page);
+	INIT_LIST_HEAD(&page->buddy_list);
+	set_page_private(page, order);
+	/* Guard pages are not available for any usage */
+	if (!is_migrate_isolate(migratetype))
+		__mod_zone_freepage_state(zone, -(1 << order), migratetype);
+
+	return true;
+}
+
+void __clear_page_guard(struct zone *zone, struct page *page, unsigned int order,
+		      int migratetype)
+{
+	__ClearPageGuard(page);
+
+	set_page_private(page, 0);
+	if (!is_migrate_isolate(migratetype))
+		__mod_zone_freepage_state(zone, (1 << order), migratetype);
+}
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 8d4e803cec44..dc9820466377 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -664,75 +664,6 @@  void destroy_large_folio(struct folio *folio)
 	compound_page_dtors[dtor](&folio->page);
 }
 
-#ifdef CONFIG_DEBUG_PAGEALLOC
-unsigned int _debug_guardpage_minorder;
-
-bool _debug_pagealloc_enabled_early __read_mostly
-			= IS_ENABLED(CONFIG_DEBUG_PAGEALLOC_ENABLE_DEFAULT);
-EXPORT_SYMBOL(_debug_pagealloc_enabled_early);
-DEFINE_STATIC_KEY_FALSE(_debug_pagealloc_enabled);
-EXPORT_SYMBOL(_debug_pagealloc_enabled);
-
-DEFINE_STATIC_KEY_FALSE(_debug_guardpage_enabled);
-
-static int __init early_debug_pagealloc(char *buf)
-{
-	return kstrtobool(buf, &_debug_pagealloc_enabled_early);
-}
-early_param("debug_pagealloc", early_debug_pagealloc);
-
-static int __init debug_guardpage_minorder_setup(char *buf)
-{
-	unsigned long res;
-
-	if (kstrtoul(buf, 10, &res) < 0 ||  res > MAX_ORDER / 2) {
-		pr_err("Bad debug_guardpage_minorder value\n");
-		return 0;
-	}
-	_debug_guardpage_minorder = res;
-	pr_info("Setting debug_guardpage_minorder to %lu\n", res);
-	return 0;
-}
-early_param("debug_guardpage_minorder", debug_guardpage_minorder_setup);
-
-static inline bool set_page_guard(struct zone *zone, struct page *page,
-				unsigned int order, int migratetype)
-{
-	if (!debug_guardpage_enabled())
-		return false;
-
-	if (order >= debug_guardpage_minorder())
-		return false;
-
-	__SetPageGuard(page);
-	INIT_LIST_HEAD(&page->buddy_list);
-	set_page_private(page, order);
-	/* Guard pages are not available for any usage */
-	if (!is_migrate_isolate(migratetype))
-		__mod_zone_freepage_state(zone, -(1 << order), migratetype);
-
-	return true;
-}
-
-static inline void clear_page_guard(struct zone *zone, struct page *page,
-				unsigned int order, int migratetype)
-{
-	if (!debug_guardpage_enabled())
-		return;
-
-	__ClearPageGuard(page);
-
-	set_page_private(page, 0);
-	if (!is_migrate_isolate(migratetype))
-		__mod_zone_freepage_state(zone, (1 << order), migratetype);
-}
-#else
-static inline bool set_page_guard(struct zone *zone, struct page *page,
-			unsigned int order, int migratetype) { return false; }
-static inline void clear_page_guard(struct zone *zone, struct page *page,
-				unsigned int order, int migratetype) {}
-#endif
-
 static inline void set_buddy_order(struct page *page, unsigned int order)
 {
 	set_page_private(page, order);