xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

btrfs: track exclusive filesystem operation in flags

Browse Source 
There are several operations, usually started from ioctls, that cannot
run concurrently. The status is tracked in
mutually_exclusive_operation_running as an atomic_t. We can easily track
the status as one of the per-filesystem flag bits with same
synchronization guarantees.

The conversion replaces:

* atomic_xchg(..., 1)    ->   test_and_set_bit(FLAG, ...)
* atomic_set(..., 0)     ->   clear_bit(FLAG, ...)

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
David Sterba
2017-03-28 14:44:21 +02:00
parent 48a89bc4f2
commit 171938e528
4 changed files with 25 additions and 26 deletions
Download Patch File Download Diff File Expand all files Collapse all files

5
fs/btrfs/dev-replace.c
View File

@@ -784,8 +784,7 @@ int btrfs_resume_dev_replace_async(struct btrfs_fs_info *fs_info)
}
btrfs_dev_replace_unlock(dev_replace, 1);
WARN_ON(atomic_xchg(
&fs_info->mutually_exclusive_operation_running, 1));
WARN_ON(test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags));
task = kthread_run(btrfs_dev_replace_kthread, fs_info, "btrfs-devrepl");
return PTR_ERR_OR_ZERO(task);
}
@@ -814,7 +813,7 @@ static int btrfs_dev_replace_kthread(void *data)
(unsigned int)progress);
}
btrfs_dev_replace_continue_on_mount(fs_info);
atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
return 0;
}