From 174ba50915b08dcfd07c8b5fb795b46a165fa09a Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Fri, 27 May 2011 10:03:58 -0400 Subject: [PATCH] Btrfs: use the device_list_mutex during write_dev_supers write_dev_supers was changed to use RCU to protect the list of devices, but it was then sleeping while it actually wrote the supers. This fixes it to just use the mutex, since we really don't any concurrency in write_dev_supers anyway. Signed-off-by: Chris Mason --- fs/btrfs/disk-io.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index b2588a552658..98b6a71decba 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -2310,7 +2310,7 @@ int write_all_supers(struct btrfs_root *root, int max_mirrors) sb = &root->fs_info->super_for_commit; dev_item = &sb->dev_item; - rcu_read_lock(); + mutex_lock(&root->fs_info->fs_devices->device_list_mutex); head = &root->fs_info->fs_devices->devices; list_for_each_entry_rcu(dev, head, dev_list) { if (!dev->bdev) { @@ -2355,7 +2355,7 @@ int write_all_supers(struct btrfs_root *root, int max_mirrors) if (ret) total_errors++; } - rcu_read_unlock(); + mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); if (total_errors > max_errors) { printk(KERN_ERR "btrfs: %d errors while writing supers\n", total_errors); -- 2.11.0