[PATCH UPDATED 02/11] blkcg: __blkg_lookup_create() doesn't need radix preload

Tejun Heo
2012-04-27T21:18:33Z

There's no point in calling radix_tree_preload() if preloading doesn't
use more permissible GFP mask. Drop preloading from
__blkg_lookup_create().

While at it, drop sparse locking annotation which no longer applies.

v2: Vivek pointed out the odd preload usage. Instead of updating,
just drop it.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
---
We don't need preloading at all. Just drop it. git branch updated
accordingly. All patches apply as-is.

Thanks.

block/blk-cgroup.c | 10 +---------
1 files changed, 1 insertions(+), 9 deletions(-)

diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 4ab7420..af61db0 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -177,7 +177,6 @@ EXPORT_SYMBOL_GPL(blkg_lookup);

static struct blkcg_gq *__blkg_lookup_create(struct blkcg *blkcg,
struct request_queue *q)
- __releases(q->queue_lock) __acquires(q->queue_lock)
{
struct blkcg_gq *blkg;
int ret;
@@ -203,10 +202,6 @@ static struct blkcg_gq *__blkg_lookup_create(struct blkcg *blkcg,
goto err_put;

/* insert */
- ret = radix_tree_preload(GFP_ATOMIC);
- if (ret)
- goto err_free;
-
spin_lock(&blkcg->lock);
ret = radix_tree_insert(&blkcg->blkg_tree, q->id, blkg);
if (likely(!ret)) {
@@ -215,14 +210,11 @@ static struct blkcg_gq *__blkg_lookup_create(struct blkcg *blkcg,
}
spin_unlock(&blkcg->lock);

- radix_tree_preload_end();
-
if (!ret)
return blkg;
-err_free:
- blkg_free(blkg);
err_put:
css_put(&blkcg->css);
+ blkg_free(blkg);
return ERR_PTR(ret);
}

--
1.7.7.3