blkio: Add more debug-only per-cgroup stats

[safe/jmp/linux-2.6] / block / elevator.c

diff --git a/block/elevator.c b/block/elevator.c
index a847046..5e73459 100644 (file)
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -154,10 +154,7 @@ static struct elevator_type *elevator_get(const char *name)
 
                spin_unlock(&elv_list_lock);
 
-               if (!strcmp(name, "anticipatory"))
-                       sprintf(elv, "as-iosched");
-               else
-                       sprintf(elv, "%s-iosched", name);
+               snprintf(elv, sizeof(elv), "%s-iosched", name);
 
                request_module("%s", elv);
                spin_lock(&elv_list_lock);
@@ -193,10 +190,7 @@ static int __init elevator_setup(char *str)
         * Be backwards-compatible with previous kernels, so users
         * won't get the wrong elevator.
         */
-       if (!strcmp(str, "as"))
-               strcpy(chosen_elevator, "anticipatory");
-       else
-               strncpy(chosen_elevator, str, sizeof(chosen_elevator) - 1);
+       strncpy(chosen_elevator, str, sizeof(chosen_elevator) - 1);
        return 1;
 }
 
@@ -480,6 +474,15 @@ int elv_merge(struct request_queue *q, struct request **req, struct bio *bio)
        int ret;
 
        /*
+        * Levels of merges:
+        *      nomerges:  No merges at all attempted
+        *      noxmerges: Only simple one-hit cache try
+        *      merges:    All merge tries attempted
+        */
+       if (blk_queue_nomerges(q))
+               return ELEVATOR_NO_MERGE;
+
+       /*
         * First try one-hit cache.
         */
        if (q->last_merge) {
@@ -490,7 +493,7 @@ int elv_merge(struct request_queue *q, struct request **req, struct bio *bio)
                }
        }
 
-       if (blk_queue_nomerges(q))
+       if (blk_queue_noxmerges(q))
                return ELEVATOR_NO_MERGE;
 
        /*
@@ -536,6 +539,15 @@ void elv_merge_requests(struct request_queue *q, struct request *rq,
        q->last_merge = rq;
 }
 
+void elv_bio_merged(struct request_queue *q, struct request *rq,
+                       struct bio *bio)
+{
+       struct elevator_queue *e = q->elevator;
+
+       if (e->ops->elevator_bio_merged_fn)
+               e->ops->elevator_bio_merged_fn(q, rq, bio);
+}
+
 void elv_requeue_request(struct request_queue *q, struct request *rq)
 {
        /*
@@ -889,7 +901,7 @@ elv_attr_store(struct kobject *kobj, struct attribute *attr,
        return error;
 }
 
-static struct sysfs_ops elv_sysfs_ops = {
+static const struct sysfs_ops elv_sysfs_ops = {
        .show   = elv_attr_show,
        .store  = elv_attr_store,
 };