Re: [PATCH] btrfs: remove BUG_ON in btrfs_rm_dev_replace_free_srcdev()

[Anand Jain <anand.jain@oracle.com>]

On 10/16/2017 10:45 PM, David Sterba wrote:
> On Thu, Oct 12, 2017 at 05:00:41PM +0800, Anand Jain wrote:
>> That was only an extra check to tackle few bugs around this
>> area, now its save to remove it.
>>
>> Signed-off-by: Anand Jain <anand.jain@oracle.com>
>> ---
>>   fs/btrfs/volumes.c | 8 ++------
>>   1 file changed, 2 insertions(+), 6 deletions(-)
>>
>> diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
>> index 332e00e72b86..0a5251a34d58 100644
>> --- a/fs/btrfs/volumes.c
>> +++ b/fs/btrfs/volumes.c
>> @@ -2015,16 +2015,12 @@ void btrfs_rm_dev_replace_free_srcdev(struct btrfs_fs_info *fs_info,
>>   	}
>>   
>>   	btrfs_close_bdev(srcdev);
>> -
>>   	call_rcu(&srcdev->rcu, free_device);
>>   
>>   	/*
>> -	 * unless fs_devices is seed fs, num_devices shouldn't go
>> -	 * zero
>> +	 * If this is no devs we rather delete the fs_devices
>> +	 * which is true in case of single device seeding fs.
> 
> Can you please rephrase the first part of the comment? I'm not sure I
> understand what it's trying to say.
> 
>>   	 */
>> -	BUG_ON(!fs_devices->num_devices && !fs_devices->seeding);
> 
> I think we could still keep the check as an ASSERT.

  OK. I have fixed these in V2.

Thanks, Anand

>> -
>> -	/* if this is no devs we rather delete the fs_devices */
>>   	if (!fs_devices->num_devices) {
>>   		struct btrfs_fs_devices *tmp_fs_devices;
>>