diff options
| author | Tejun Heo <tj@kernel.org> | 2008-09-03 08:53:37 +0200 |
|---|---|---|
| committer | Jens Axboe <jens.axboe@oracle.com> | 2008-10-09 08:56:04 +0200 |
| commit | 2ac3cee5298a247b2774f3319b28a05f588c3f0e (patch) | |
| tree | e297bbd502f1a8a52436358c5184f7de1cb43f56 /block/genhd.c | |
| parent | ac65ece4eee10b03ac29ee925cadc179dc810bab (diff) | |
| download | lwn-2ac3cee5298a247b2774f3319b28a05f588c3f0e.tar.gz lwn-2ac3cee5298a247b2774f3319b28a05f588c3f0e.zip | |
block: don't grab block_class_lock unnecessarily
block_class_lock protects major_names array and bdev_map and doesn't
have anything to do with block class devices. Don't grab them while
iterating over block class devices.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Diffstat (limited to 'block/genhd.c')
| -rw-r--r-- | block/genhd.c | 28 |
1 files changed, 9 insertions, 19 deletions
diff --git a/block/genhd.c b/block/genhd.c index 0be95135c404..9eb8b3e212c1 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -283,9 +283,7 @@ static int printk_partition(struct device *dev, void *data) */ void __init printk_all_partitions(void) { - mutex_lock(&block_class_lock); class_for_each_device(&block_class, NULL, NULL, printk_partition); - mutex_unlock(&block_class_lock); } #ifdef CONFIG_PROC_FS @@ -305,17 +303,15 @@ static int find_start(struct device *dev, void *data) static void *part_start(struct seq_file *part, loff_t *pos) { struct device *dev; - loff_t k = *pos; + loff_t n = *pos; - if (!k) + if (!n) part->private = (void *)1LU; /* tell show to print header */ - mutex_lock(&block_class_lock); - dev = class_find_device(&block_class, NULL, &k, find_start); - if (dev) { - put_device(dev); + dev = class_find_device(&block_class, NULL, &n, find_start); + if (dev) return dev_to_disk(dev); - } + return NULL; } @@ -341,7 +337,6 @@ static void *part_next(struct seq_file *part, void *v, loff_t *pos) static void part_stop(struct seq_file *part, void *v) { - mutex_unlock(&block_class_lock); } static int show_partition(struct seq_file *part, void *v) @@ -583,14 +578,12 @@ static struct device_type disk_type = { static void *diskstats_start(struct seq_file *part, loff_t *pos) { struct device *dev; - loff_t k = *pos; + loff_t n = *pos; - mutex_lock(&block_class_lock); - dev = class_find_device(&block_class, NULL, &k, find_start); - if (dev) { - put_device(dev); + dev = class_find_device(&block_class, NULL, &n, find_start); + if (dev) return dev_to_disk(dev); - } + return NULL; } @@ -610,7 +603,6 @@ static void *diskstats_next(struct seq_file *part, void *v, loff_t *pos) static void diskstats_stop(struct seq_file *part, void *v) { - mutex_unlock(&block_class_lock); } static int diskstats_show(struct seq_file *s, void *v) @@ -729,7 +721,6 @@ dev_t blk_lookup_devt(const char *name, int part) dev_t devt = MKDEV(0, 0); struct find_block find; - mutex_lock(&block_class_lock); find.name = name; find.part = part; dev = class_find_device(&block_class, NULL, &find, match_id); @@ -738,7 +729,6 @@ dev_t blk_lookup_devt(const char *name, int part) devt = MKDEV(MAJOR(dev->devt), MINOR(dev->devt) + part); } - mutex_unlock(&block_class_lock); return devt; } |