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 Also remove out of date comment for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>
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index 21e275d..a29cb78 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -88,9 +88,7 @@
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 @@
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);