Merge branch 'slab/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux

* 'slab/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux:
  tools, slub: Fix off-by-one buffer corruption after readlink() call
  slub: Discard slab page when node partial > minimum partial number
  slub: correct comments error for per cpu partial
  mm: restrict access to slab files under procfs and sysfs
  slub: Code optimization in get_partial_node()
  slub: doc: update the slabinfo.c file path
  slub: explicitly document position of inserting slab to partial list
  slub: update slabinfo tools to report per cpu partial list statistics
  slub: per cpu cache for partial pages
  slub: return object pointer from get_partial() / new_slab().
  slub: pass kmem_cache_cpu pointer to get_partial()
  slub: Prepare inuse field in new_slab()
  slub: Remove useless statements in __slab_alloc
  slub: free slabs without holding locks
  slub: use print_hex_dump
  slab: use print_hex_dump

Documentation/vm/00-INDEX

@@ -30,8 +30,6 @@ page_migration
 	- description of page migration in NUMA systems.
 pagemap.txt
 	- pagemap, from the userspace perspective
-slabinfo.c
-	- source code for a tool to get reports about slabs.
 slub.txt
 	- a short users guide for SLUB.
 unevictable-lru.txt

include/linux/mm_types.h

@@ -79,9 +79,21 @@ struct page {
 	};
 
 	/* Third double word block */
+	union {
 		struct list_head lru;	/* Pageout list, eg. active_list
 					 * protected by zone->lru_lock !
 					 */
+		struct {		/* slub per cpu partial pages */
+			struct page *next;	/* Next partial slab */
+#ifdef CONFIG_64BIT
+			int pages;	/* Nr of partial slabs left */
+			int pobjects;	/* Approximate # of objects */
+#else
+			short int pages;
+			short int pobjects;
+#endif
+		};
+	};
 
 	/* Remainder is not double word aligned */
 	union {

include/linux/slub_def.h

@@ -36,12 +36,15 @@ enum stat_item {
 	ORDER_FALLBACK,		/* Number of times fallback was necessary */
 	CMPXCHG_DOUBLE_CPU_FAIL,/* Failure of this_cpu_cmpxchg_double */
 	CMPXCHG_DOUBLE_FAIL,	/* Number of times that cmpxchg double did not match */
+	CPU_PARTIAL_ALLOC,	/* Used cpu partial on alloc */
+	CPU_PARTIAL_FREE,	/* USed cpu partial on free */
 	NR_SLUB_STAT_ITEMS };
 
 struct kmem_cache_cpu {
 	void **freelist;	/* Pointer to next available object */
 	unsigned long tid;	/* Globally unique transaction id */
 	struct page *page;	/* The slab from which we are allocating */
+	struct page *partial;	/* Partially allocated frozen slabs */
 	int node;		/* The node of the page (or -1 for debug) */
 #ifdef CONFIG_SLUB_STATS
 	unsigned stat[NR_SLUB_STAT_ITEMS];
@@ -79,6 +82,7 @@ struct kmem_cache {
 	int size;		/* The size of an object including meta data */
 	int objsize;		/* The size of an object without meta data */
 	int offset;		/* Free pointer offset. */
+	int cpu_partial;	/* Number of per cpu partial objects to keep around */
 	struct kmem_cache_order_objects oo;
 
 	/* Allocation and freeing of slabs */

mm/slab.c

@@ -1851,15 +1851,15 @@ static void dump_line(char *data, int offset, int limit)
 	unsigned char error = 0;
 	int bad_count = 0;
 
-	printk(KERN_ERR "%03x:", offset);
+	printk(KERN_ERR "%03x: ", offset);
 	for (i = 0; i < limit; i++) {
 		if (data[offset + i] != POISON_FREE) {
 			error = data[offset + i];
 			bad_count++;
 		}
-		printk(" %02x", (unsigned char)data[offset + i]);
 	}
-	printk("\n");
+	print_hex_dump(KERN_CONT, "", 0, 16, 1,
+			&data[offset], limit, 1);
 
 	if (bad_count == 1) {
 		error ^= POISON_FREE;
@@ -3039,14 +3039,9 @@ static void check_slabp(struct kmem_cache *cachep, struct slab *slabp)
 		printk(KERN_ERR "slab: Internal list corruption detected in "
 				"cache '%s'(%d), slabp %p(%d). Hexdump:\n",
 			cachep->name, cachep->num, slabp, slabp->inuse);
-		for (i = 0;
-		     i < sizeof(*slabp) + cachep->num * sizeof(kmem_bufctl_t);
-		     i++) {
-			if (i % 16 == 0)
-				printk("\n%03x:", i);
-			printk(" %02x", ((unsigned char *)slabp)[i]);
-		}
-		printk("\n");
+		print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 16, 1, slabp,
+			sizeof(*slabp) + cachep->num * sizeof(kmem_bufctl_t),
+			1);
 		BUG();
 	}
 }
@@ -4584,7 +4579,7 @@ static const struct file_operations proc_slabstats_operations = {
 
 static int __init slab_proc_init(void)
 {
-	proc_create("slabinfo",S_IWUSR|S_IRUGO,NULL,&proc_slabinfo_operations);
+	proc_create("slabinfo",S_IWUSR|S_IRUSR,NULL,&proc_slabinfo_operations);
 #ifdef CONFIG_DEBUG_SLAB_LEAK
 	proc_create("slab_allocators", 0, NULL, &proc_slabstats_operations);
 #endif

tools/slub/slabinfo.c

@@ -42,6 +42,7 @@ struct slabinfo {
 	unsigned long deactivate_remote_frees, order_fallback;
 	unsigned long cmpxchg_double_cpu_fail, cmpxchg_double_fail;
 	unsigned long alloc_node_mismatch, deactivate_bypass;
+	unsigned long cpu_partial_alloc, cpu_partial_free;
 	int numa[MAX_NODES];
 	int numa_partial[MAX_NODES];
 } slabinfo[MAX_SLABS];
@@ -455,6 +456,11 @@ static void slab_stats(struct slabinfo *s)
 		s->alloc_from_partial * 100 / total_alloc,
 		s->free_remove_partial * 100 / total_free);
 
+	printf("Cpu partial list     %8lu %8lu %3lu %3lu\n",
+		s->cpu_partial_alloc, s->cpu_partial_free,
+		s->cpu_partial_alloc * 100 / total_alloc,
+		s->cpu_partial_free * 100 / total_free);
+
 	printf("RemoteObj/SlabFrozen %8lu %8lu %3lu %3lu\n",
 		s->deactivate_remote_frees, s->free_frozen,
 		s->deactivate_remote_frees * 100 / total_alloc,
@@ -1145,7 +1151,7 @@ static void read_slab_dir(void)
 		switch (de->d_type) {
 		   case DT_LNK:
 			alias->name = strdup(de->d_name);
-			count = readlink(de->d_name, buffer, sizeof(buffer));
+			count = readlink(de->d_name, buffer, sizeof(buffer)-1);
 
 			if (count < 0)
 				fatal("Cannot read symlink %s\n", de->d_name);
@@ -1209,6 +1215,8 @@ static void read_slab_dir(void)
 			slab->order_fallback = get_obj("order_fallback");
 			slab->cmpxchg_double_cpu_fail = get_obj("cmpxchg_double_cpu_fail");
 			slab->cmpxchg_double_fail = get_obj("cmpxchg_double_fail");
+			slab->cpu_partial_alloc = get_obj("cpu_partial_alloc");
+			slab->cpu_partial_free = get_obj("cpu_partial_free");
 			slab->alloc_node_mismatch = get_obj("alloc_node_mismatch");
 			slab->deactivate_bypass = get_obj("deactivate_bypass");
 			chdir("..");