IEEE1394(r1168): Add on a mempool for packet allocation, in addition to the kmem_cache.

drivers/ieee1394/ieee1394_core.c

@@ -31,6 +31,7 @@
 #include <linux/moduleparam.h>
 #include <linux/bitops.h>
 #include <linux/kdev_t.h>
+#include <linux/mempool.h>
 #include <asm/byteorder.h>
 #include <asm/semaphore.h>
 
@@ -56,6 +57,7 @@ MODULE_PARM_DESC(disable_nodemgr, "Disable nodemgr functionality.");
 MODULE_LICENSE("GPL");
 
 static kmem_cache_t *hpsb_packet_cache;
+static mempool_t *hpsb_packet_mempool;
 
 /* Some globals used */
 const char *hpsb_speedto_str[] = { "S100", "S200", "S400", "S800", "S1600", "S3200" };
@@ -92,7 +94,7 @@ static void queue_packet_complete(struct hpsb_packet *packet);
 void hpsb_set_packet_complete_task(struct hpsb_packet *packet,
 				   void (*routine)(void *), void *data)
 {
-	BUG_ON(packet->complete_routine != NULL);
+	WARN_ON(packet->complete_routine != NULL);
 	packet->complete_routine = routine;
 	packet->complete_data = data;
 	return;
@@ -123,14 +125,15 @@ struct hpsb_packet *hpsb_alloc_packet(size_t data_size)
         struct hpsb_packet *packet = NULL;
         void *data = NULL;
 
-        packet = kmem_cache_alloc(hpsb_packet_cache, GFP_ATOMIC);
+	packet = mempool_alloc(hpsb_packet_mempool, GFP_ATOMIC);
         if (packet == NULL)
                 return NULL;
 
         if (data_size) {
+		data_size = (data_size + 3) & ~3;
                 data = kmalloc(data_size + 8, GFP_ATOMIC);
                 if (data == NULL) {
-			kmem_cache_free(hpsb_packet_cache, packet);
+			mempool_free(packet, hpsb_packet_mempool);
                         return NULL;
                 }
 
@@ -152,7 +155,7 @@ void hpsb_free_packet(struct hpsb_packet *packet)
 {
 	if (packet && atomic_dec_and_test(&packet->refcnt)) {
 		kfree(packet->data);
-		kmem_cache_free(hpsb_packet_cache, packet);
+		mempool_free(packet, hpsb_packet_mempool);
 	}
 }
 
@@ -1065,7 +1068,14 @@ static int __init ieee1394_init(void)
 	devfs_mk_dir("ieee1394");
 
 	hpsb_packet_cache = kmem_cache_create("hpsb_packet", sizeof(struct hpsb_packet),
-					      0, 0, hpsb_packet_ctor, NULL);
+					      0, SLAB_HWCACHE_ALIGN, hpsb_packet_ctor, NULL);
+	/* Our memory pool keeps 32 packets allocated at all times. The
+	 * default callbacks use the hpsb_packet_cache for the allocation,
+	 * and the hpsb_packet_ctor call back makes sure that the packets
+	 * are setup properly. Smooooth. */
+	hpsb_packet_mempool = mempool_create(32, mempool_alloc_slab,
+					       mempool_free_slab,
+					       hpsb_packet_cache);
 
 	bus_register(&ieee1394_bus_type);
 	for (i = 0; fw_bus_attrs[i]; i++)
@@ -1102,6 +1112,7 @@ static void __exit ieee1394_cleanup(void)
 		wait_for_completion(&khpsbpkt_complete);
 	}
 
+	mempool_destroy(hpsb_packet_mempool);
 	kmem_cache_destroy(hpsb_packet_cache);
 
 	unregister_chrdev_region(IEEE1394_CORE_DEV, 256);