linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: js1304@gmail.com
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Lameter <cl@linux.com>,
	Pekka Enberg <penberg@kernel.org>,
	David Rientjes <rientjes@google.com>,
	Jesper Dangaard Brouer <brouer@redhat.com>,
	Vlastimil Babka <vbabka@suse.cz>,
	linux-mm@kvack.org, linux-kernel@vger.kernel.org,
	Joonsoo Kim <iamjoonsoo.kim@lge.com>
Subject: [PATCH v2 06/17] mm/slab: clean up DEBUG_PAGEALLOC processing code
Date: Fri, 26 Feb 2016 15:01:13 +0900	[thread overview]
Message-ID: <1456466484-3442-7-git-send-email-iamjoonsoo.kim@lge.com> (raw)
In-Reply-To: <1456466484-3442-1-git-send-email-iamjoonsoo.kim@lge.com>

From: Joonsoo Kim <iamjoonsoo.kim@lge.com>

Currently, open code for checking DEBUG_PAGEALLOC cache is spread to some
sites.  It makes code unreadable and hard to change.  This patch clean-up
these code.  Following patch will change the criteria for DEBUG_PAGEALLOC
cache so this clean-up will help it, too.

v2: fix build with CONFIG_DEBUG_PAGEALLOC=n by Andrew

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
 include/linux/mm.h | 12 ++++---
 mm/slab.c          | 97 +++++++++++++++++++++++++++---------------------------
 2 files changed, 57 insertions(+), 52 deletions(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 516e149..7c6d47d 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2194,14 +2194,18 @@ kernel_map_pages(struct page *page, int numpages, int enable)
 }
 #ifdef CONFIG_HIBERNATION
 extern bool kernel_page_present(struct page *page);
-#endif /* CONFIG_HIBERNATION */
-#else
+#endif	/* CONFIG_HIBERNATION */
+#else	/* CONFIG_DEBUG_PAGEALLOC */
 static inline void
 kernel_map_pages(struct page *page, int numpages, int enable) {}
 #ifdef CONFIG_HIBERNATION
 static inline bool kernel_page_present(struct page *page) { return true; }
-#endif /* CONFIG_HIBERNATION */
-#endif
+#endif	/* CONFIG_HIBERNATION */
+static inline bool debug_pagealloc_enabled(void)
+{
+	return false;
+}
+#endif	/* CONFIG_DEBUG_PAGEALLOC */
 
 #ifdef __HAVE_ARCH_GATE_AREA
 extern struct vm_area_struct *get_gate_vma(struct mm_struct *mm);
diff --git a/mm/slab.c b/mm/slab.c
index 8bca9be..3142ec3 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -1661,6 +1661,14 @@ static void kmem_rcu_free(struct rcu_head *head)
 }
 
 #if DEBUG
+static bool is_debug_pagealloc_cache(struct kmem_cache *cachep)
+{
+	if (debug_pagealloc_enabled() && OFF_SLAB(cachep) &&
+		(cachep->size % PAGE_SIZE) == 0)
+		return true;
+
+	return false;
+}
 
 #ifdef CONFIG_DEBUG_PAGEALLOC
 static void store_stackinfo(struct kmem_cache *cachep, unsigned long *addr,
@@ -1694,6 +1702,23 @@ static void store_stackinfo(struct kmem_cache *cachep, unsigned long *addr,
 	}
 	*addr++ = 0x87654321;
 }
+
+static void slab_kernel_map(struct kmem_cache *cachep, void *objp,
+				int map, unsigned long caller)
+{
+	if (!is_debug_pagealloc_cache(cachep))
+		return;
+
+	if (caller)
+		store_stackinfo(cachep, objp, caller);
+
+	kernel_map_pages(virt_to_page(objp), cachep->size / PAGE_SIZE, map);
+}
+
+#else
+static inline void slab_kernel_map(struct kmem_cache *cachep, void *objp,
+				int map, unsigned long caller) {}
+
 #endif
 
 static void poison_obj(struct kmem_cache *cachep, void *addr, unsigned char val)
@@ -1772,6 +1797,9 @@ static void check_poison_obj(struct kmem_cache *cachep, void *objp)
 	int size, i;
 	int lines = 0;
 
+	if (is_debug_pagealloc_cache(cachep))
+		return;
+
 	realobj = (char *)objp + obj_offset(cachep);
 	size = cachep->object_size;
 
@@ -1837,17 +1865,8 @@ static void slab_destroy_debugcheck(struct kmem_cache *cachep,
 		void *objp = index_to_obj(cachep, page, i);
 
 		if (cachep->flags & SLAB_POISON) {
-#ifdef CONFIG_DEBUG_PAGEALLOC
-			if (debug_pagealloc_enabled() &&
-				cachep->size % PAGE_SIZE == 0 &&
-					OFF_SLAB(cachep))
-				kernel_map_pages(virt_to_page(objp),
-					cachep->size / PAGE_SIZE, 1);
-			else
-				check_poison_obj(cachep, objp);
-#else
 			check_poison_obj(cachep, objp);
-#endif
+			slab_kernel_map(cachep, objp, 1, 0);
 		}
 		if (cachep->flags & SLAB_RED_ZONE) {
 			if (*dbg_redzone1(cachep, objp) != RED_INACTIVE)
@@ -2226,16 +2245,6 @@ __kmem_cache_create (struct kmem_cache *cachep, unsigned long flags)
 	if (flags & CFLGS_OFF_SLAB) {
 		/* really off slab. No need for manual alignment */
 		freelist_size = calculate_freelist_size(cachep->num, 0);
-
-#ifdef CONFIG_PAGE_POISONING
-		/* If we're going to use the generic kernel_map_pages()
-		 * poisoning, then it's going to smash the contents of
-		 * the redzone and userword anyhow, so switch them off.
-		 */
-		if (debug_pagealloc_enabled() &&
-			size % PAGE_SIZE == 0 && flags & SLAB_POISON)
-			flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER);
-#endif
 	}
 
 	cachep->colour_off = cache_line_size();
@@ -2251,7 +2260,19 @@ __kmem_cache_create (struct kmem_cache *cachep, unsigned long flags)
 	cachep->size = size;
 	cachep->reciprocal_buffer_size = reciprocal_value(size);
 
-	if (flags & CFLGS_OFF_SLAB) {
+#if DEBUG
+	/*
+	 * If we're going to use the generic kernel_map_pages()
+	 * poisoning, then it's going to smash the contents of
+	 * the redzone and userword anyhow, so switch them off.
+	 */
+	if (IS_ENABLED(CONFIG_PAGE_POISONING) &&
+		(cachep->flags & SLAB_POISON) &&
+		is_debug_pagealloc_cache(cachep))
+		cachep->flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER);
+#endif
+
+	if (OFF_SLAB(cachep)) {
 		cachep->freelist_cache = kmalloc_slab(freelist_size, 0u);
 		/*
 		 * This is a possibility for one of the kmalloc_{dma,}_caches.
@@ -2475,9 +2496,6 @@ static void cache_init_objs(struct kmem_cache *cachep,
 	for (i = 0; i < cachep->num; i++) {
 		void *objp = index_to_obj(cachep, page, i);
 #if DEBUG
-		/* need to poison the objs? */
-		if (cachep->flags & SLAB_POISON)
-			poison_obj(cachep, objp, POISON_FREE);
 		if (cachep->flags & SLAB_STORE_USER)
 			*dbg_userword(cachep, objp) = NULL;
 
@@ -2501,10 +2519,11 @@ static void cache_init_objs(struct kmem_cache *cachep,
 				slab_error(cachep, "constructor overwrote the"
 					   " start of an object");
 		}
-		if ((cachep->size % PAGE_SIZE) == 0 &&
-			    OFF_SLAB(cachep) && cachep->flags & SLAB_POISON)
-			kernel_map_pages(virt_to_page(objp),
-					 cachep->size / PAGE_SIZE, 0);
+		/* need to poison the objs? */
+		if (cachep->flags & SLAB_POISON) {
+			poison_obj(cachep, objp, POISON_FREE);
+			slab_kernel_map(cachep, objp, 0, 0);
+		}
 #else
 		if (cachep->ctor)
 			cachep->ctor(objp);
@@ -2716,18 +2735,8 @@ static void *cache_free_debugcheck(struct kmem_cache *cachep, void *objp,
 
 	set_obj_status(page, objnr, OBJECT_FREE);
 	if (cachep->flags & SLAB_POISON) {
-#ifdef CONFIG_DEBUG_PAGEALLOC
-		if (debug_pagealloc_enabled() &&
-			(cachep->size % PAGE_SIZE) == 0 && OFF_SLAB(cachep)) {
-			store_stackinfo(cachep, objp, caller);
-			kernel_map_pages(virt_to_page(objp),
-					 cachep->size / PAGE_SIZE, 0);
-		} else {
-			poison_obj(cachep, objp, POISON_FREE);
-		}
-#else
 		poison_obj(cachep, objp, POISON_FREE);
-#endif
+		slab_kernel_map(cachep, objp, 0, caller);
 	}
 	return objp;
 }
@@ -2862,16 +2871,8 @@ static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep,
 	if (!objp)
 		return objp;
 	if (cachep->flags & SLAB_POISON) {
-#ifdef CONFIG_DEBUG_PAGEALLOC
-		if (debug_pagealloc_enabled() &&
-			(cachep->size % PAGE_SIZE) == 0 && OFF_SLAB(cachep))
-			kernel_map_pages(virt_to_page(objp),
-					 cachep->size / PAGE_SIZE, 1);
-		else
-			check_poison_obj(cachep, objp);
-#else
 		check_poison_obj(cachep, objp);
-#endif
+		slab_kernel_map(cachep, objp, 1, 0);
 		poison_obj(cachep, objp, POISON_INUSE);
 	}
 	if (cachep->flags & SLAB_STORE_USER)
-- 
1.9.1

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

  parent reply	other threads:[~2016-02-26  6:01 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-02-26  6:01 [PATCH v2 00/17] mm/slab: introduce new freed objects management way, OBJFREELIST_SLAB js1304
2016-02-26  6:01 ` [PATCH v2 01/17] mm/slab: fix stale code comment js1304
2016-02-26  6:01 ` [PATCH v2 02/17] mm/slab: remove useless structure define js1304
2016-02-26  6:01 ` [PATCH v2 03/17] mm/slab: remove the checks for slab implementation bug js1304
2016-02-26 16:05   ` Christoph Lameter
2016-02-26  6:01 ` [PATCH v2 04/17] mm/slab: activate debug_pagealloc in SLAB when it is actually enabled js1304
2016-02-26 16:06   ` Christoph Lameter
2016-02-26  6:01 ` [PATCH v2 05/17] mm/slab: use more appropriate condition check for debug_pagealloc js1304
2016-02-26 16:08   ` Christoph Lameter
2016-02-26  6:01 ` js1304 [this message]
2016-02-26  6:01 ` [PATCH v2 07/17] mm/slab: alternative implementation for DEBUG_SLAB_LEAK js1304
2016-02-26  6:01 ` [PATCH v2 08/17] mm/slab: remove object status buffer " js1304
2016-02-26  6:01 ` [PATCH v2 09/17] mm/slab: put the freelist at the end of slab page js1304
2016-02-26  6:01 ` [PATCH v2 10/17] mm/slab: align cache size first before determination of OFF_SLAB candidate js1304
2016-02-26  6:01 ` [PATCH v2 11/17] mm/slab: clean up cache type determination js1304
2016-02-26  6:01 ` [PATCH v2 12/17] mm/slab: do not change cache size if debug pagealloc isn't possible js1304
2016-02-26 16:13   ` Christoph Lameter
2016-02-26 17:02     ` Joonsoo Kim
2016-02-26  6:01 ` [PATCH v2 13/17] mm/slab: make criteria for off slab determination robust and simple js1304
2016-02-26  6:01 ` [PATCH v2 14/17] mm/slab: factor out slab list fixup code js1304
2016-02-26  6:01 ` [PATCH v2 15/17] mm/slab: factor out debugging initialization in cache_init_objs() js1304
2016-02-26  6:01 ` [PATCH v2 16/17] mm/slab: introduce new slab management type, OBJFREELIST_SLAB js1304
2016-02-26 16:21   ` Christoph Lameter
2016-02-26 17:06     ` Joonsoo Kim
2016-02-26  6:01 ` [PATCH v2 17/17] mm/slab: avoid returning values by reference js1304
2016-02-26 16:22   ` Christoph Lameter

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1456466484-3442-7-git-send-email-iamjoonsoo.kim@lge.com \
    --to=js1304@gmail.com \
    --cc=akpm@linux-foundation.org \
    --cc=brouer@redhat.com \
    --cc=cl@linux.com \
    --cc=iamjoonsoo.kim@lge.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=penberg@kernel.org \
    --cc=rientjes@google.com \
    --cc=vbabka@suse.cz \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox