block: don't take lock on changing ra_pages

There's no need to take queue_lock or kernel_lock when modifying
bdi->ra_pages. So remove them. Also remove out of date comment for
queue_max_sectors_store().

Signed-off-by: Wu Fengguang <wfg@linux.intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This commit is contained in:
Wu Fengguang 2008-11-25 09:08:39 +01:00 committed by Jens Axboe
parent 4236469099
commit 7c239517d9
3 changed files with 1 additions and 10 deletions

View file

@ -88,9 +88,7 @@ queue_ra_store(struct request_queue *q, const char *page, size_t count)
unsigned long ra_kb;
ssize_t ret = queue_var_store(&ra_kb, page, count);
spin_lock_irq(q->queue_lock);
q->backing_dev_info.ra_pages = ra_kb >> (PAGE_CACHE_SHIFT - 10);
spin_unlock_irq(q->queue_lock);
return ret;
}
@ -117,10 +115,7 @@ queue_max_sectors_store(struct request_queue *q, const char *page, size_t count)
if (max_sectors_kb > max_hw_sectors_kb || max_sectors_kb < page_kb)
return -EINVAL;
/*
* Take the queue lock to update the readahead and max_sectors
* values synchronously:
*/
spin_lock_irq(q->queue_lock);
q->max_sectors = max_sectors_kb << 1;
spin_unlock_irq(q->queue_lock);

View file

@ -774,9 +774,7 @@ long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
bdi = blk_get_backing_dev_info(bdev);
if (bdi == NULL)
return -ENOTTY;
lock_kernel();
bdi->ra_pages = (arg * 512) / PAGE_CACHE_SIZE;
unlock_kernel();
return 0;
case BLKGETSIZE:
size = bdev->bd_inode->i_size;

View file

@ -323,9 +323,7 @@ int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
bdi = blk_get_backing_dev_info(bdev);
if (bdi == NULL)
return -ENOTTY;
lock_kernel();
bdi->ra_pages = (arg * 512) / PAGE_CACHE_SIZE;
unlock_kernel();
return 0;
case BLKBSZSET:
/* set the logical block size */