[PATCH] add kmalloc_node, inline cleanup

The patch makes the following function calls available to allocate memory
on a specific node without changing the basic operation of the slab
allocator:

kmem_cache_alloc_node(kmem_cache_t *cachep, unsigned int flags, int node);
kmalloc_node(size_t size, unsigned int flags, int node);

in a similar way to the existing node-blind functions:

kmem_cache_alloc(kmem_cache_t *cachep, unsigned int flags);
kmalloc(size, flags);

kmem_cache_alloc_node was changed to pass flags and the node information
through the existing layers of the slab allocator (which lead to some minor
rearrangements). The functions at the lowest layer (kmem_getpages,
cache_grow) are already node aware. Also __alloc_percpu can call
kmalloc_node now.

Performance measurements (using the pageset localization patch) yields:

w/o patches:
Tasks jobs/min jti jobs/min/task real cpu
1 484.27 100 484.2736 12.02 1.97 Wed Mar 30 20:50:43 2005
100 25170.83 91 251.7083 23.12 150.10 Wed Mar 30 20:51:06 2005
200 34601.66 84 173.0083 33.64 294.14 Wed Mar 30 20:51:40 2005
300 37154.47 86 123.8482 46.99 436.56 Wed Mar 30 20:52:28 2005
400 39839.82 80 99.5995 58.43 580.46 Wed Mar 30 20:53:27 2005
500 40036.32 79 80.0726 72.68 728.60 Wed Mar 30 20:54:40 2005
600 44074.21 79 73.4570 79.23 872.10 Wed Mar 30 20:55:59 2005
700 44016.60 78 62.8809 92.56 1015.84 Wed Mar 30 20:57:32 2005
800 40411.05 80 50.5138 115.22 1161.13 Wed Mar 30 20:59:28 2005
900 42298.56 79 46.9984 123.83 1303.42 Wed Mar 30 21:01:33 2005
1000 40955.05 80 40.9551 142.11 1441.92 Wed Mar 30 21:03:55 2005

with pageset localization and slab API patches:
Tasks jobs/min jti jobs/min/task real cpu
1 484.19 100 484.1930 12.02 1.98 Wed Mar 30 21:10:18 2005
100 27428.25 92 274.2825 21.22 149.79 Wed Mar 30 21:10:40 2005
200 37228.94 86 186.1447 31.27 293.49 Wed Mar 30 21:11:12 2005
300 41725.42 85 139.0847 41.84 434.10 Wed Mar 30 21:11:54 2005
400 43032.22 82 107.5805 54.10 582.06 Wed Mar 30 21:12:48 2005
500 42211.23 83 84.4225 68.94 722.61 Wed Mar 30 21:13:58 2005
600 40084.49 82 66.8075 87.12 873.11 Wed Mar 30 21:15:25 2005
700 44169.30 79 63.0990 92.24 1008.77 Wed Mar 30 21:16:58 2005
800 43097.94 79 53.8724 108.03 1155.88 Wed Mar 30 21:18:47 2005
900 41846.75 79 46.4964 125.17 1303.38 Wed Mar 30 21:20:52 2005
1000 40247.85 79 40.2478 144.60 1442.21 Wed Mar 30 21:23:17 2005

Signed-off-by: Christoph Lameter <[e-mail]>
Signed-off-by: Manfred Spraul <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

include/linux/slab.h

···
 extern int kmem_cache_destroy(kmem_cache_t *);
 extern int kmem_cache_shrink(kmem_cache_t *);
 extern void *kmem_cache_alloc(kmem_cache_t *, unsigned int __nocast);
-#ifdef CONFIG_NUMA
-extern void *kmem_cache_alloc_node(kmem_cache_t *, int);
-#else
-static inline void *kmem_cache_alloc_node(kmem_cache_t *cachep, int node)
-{
-	return kmem_cache_alloc(cachep, GFP_KERNEL);
-}
-#endif
 extern void kmem_cache_free(kmem_cache_t *, void *);
 extern unsigned int kmem_cache_size(kmem_cache_t *);
+extern kmem_cache_t *kmem_find_general_cachep(size_t size, int gfpflags);
 
 /* Size description struct for general caches. */
 struct cache_sizes {
···
 extern void *kcalloc(size_t, size_t, unsigned int __nocast);
 extern void kfree(const void *);
 extern unsigned int ksize(const void *);
+
+#ifdef CONFIG_NUMA
+extern void *kmem_cache_alloc_node(kmem_cache_t *, int flags, int node);
+extern void *kmalloc_node(size_t size, int flags, int node);
+#else
+static inline void *kmem_cache_alloc_node(kmem_cache_t *cachep, int flags, int node)
+{
+	return kmem_cache_alloc(cachep, flags);
+}
+static inline void *kmalloc_node(size_t size, int flags, int node)
+{
+	return kmalloc(size, flags);
+}
+#endif
 
 extern int FASTCALL(kmem_cache_reap(int));
 extern int FASTCALL(kmem_ptr_validate(kmem_cache_t *cachep, void *ptr));

mm/slab.c

···
 	return cachep->array[smp_processor_id()];
 }
 
-static inline kmem_cache_t *kmem_find_general_cachep(size_t size, int gfpflags)
+static inline kmem_cache_t *__find_general_cachep(size_t size, int gfpflags)
 {
 	struct cache_sizes *csizep = malloc_sizes;
 
···
 		return csizep->cs_dmacachep;
 	return csizep->cs_cachep;
 }
+
+kmem_cache_t *kmem_find_general_cachep(size_t size, int gfpflags)
+{
+	return __find_general_cachep(size, gfpflags);
+}
+EXPORT_SYMBOL(kmem_find_general_cachep);
 
 /* Cal the num objs, wastage, and bytes left over for a given slab size. */
 static void cache_estimate(unsigned long gfporder, size_t size, size_t align,
···
 	int memsize = sizeof(void*)*entries+sizeof(struct array_cache);
 	struct array_cache *nc = NULL;
 
-	if (cpu != -1) {
-		kmem_cache_t *cachep;
-		cachep = kmem_find_general_cachep(memsize, GFP_KERNEL);
-		if (cachep)
-			nc = kmem_cache_alloc_node(cachep, cpu_to_node(cpu));
-	}
-	if (!nc)
+	if (cpu == -1)
 		nc = kmalloc(memsize, GFP_KERNEL);
+	else
+		nc = kmalloc_node(memsize, GFP_KERNEL, cpu_to_node(cpu));
+
 	if (nc) {
 		nc->avail = 0;
 		nc->limit = entries;
···
  * and can sleep. And it will allocate memory on the given node, which
  * can improve the performance for cpu bound structures.
  */
-void *kmem_cache_alloc_node(kmem_cache_t *cachep, int nodeid)
+void *kmem_cache_alloc_node(kmem_cache_t *cachep, int flags, int nodeid)
 {
 	int loop;
 	void *objp;
···
 		spin_unlock_irq(&cachep->spinlock);
 
 		local_irq_disable();
-		if (!cache_grow(cachep, GFP_KERNEL, nodeid)) {
+		if (!cache_grow(cachep, flags, nodeid)) {
 			local_irq_enable();
 			return NULL;
 		}
···
 }
 EXPORT_SYMBOL(kmem_cache_alloc_node);
 
+void *kmalloc_node(size_t size, int flags, int node)
+{
+	kmem_cache_t *cachep;
+
+	cachep = kmem_find_general_cachep(size, flags);
+	if (unlikely(cachep == NULL))
+		return NULL;
+	return kmem_cache_alloc_node(cachep, flags, node);
+}
+EXPORT_SYMBOL(kmalloc_node);
 #endif
 
 /**
···
 {
 	kmem_cache_t *cachep;
 
-	cachep = kmem_find_general_cachep(size, flags);
+	/* If you want to save a few bytes .text space: replace
+	 * __ with kmem_.
+	 * Then kmalloc uses the uninlined functions instead of the inline
+	 * functions.
+	 */
+	cachep = __find_general_cachep(size, flags);
 	if (unlikely(cachep == NULL))
 		return NULL;
 	return __cache_alloc(cachep, flags);
···
 	for (i = 0; i < NR_CPUS; i++) {
 		if (!cpu_possible(i))
 			continue;
-		pdata->ptrs[i] = kmem_cache_alloc_node(
-				kmem_find_general_cachep(size, GFP_KERNEL),
-				cpu_to_node(i));
+		pdata->ptrs[i] = kmalloc_node(size, GFP_KERNEL,
+						cpu_to_node(i));
 
 		if (!pdata->ptrs[i])
 			goto unwind_oom;