Re: [PATCH] jbd2: Make barrier messages less scary

[Eric Sandeen <sandeen@redhat.com>]

Ted Ts'o wrote:
> On Mon, Jul 26, 2010 at 02:42:13PM -0500, Eric Sandeen wrote:
>> Saying things like "sync failed" when a device does
>> not support barriers makes users slightly more worried than
>> they need to be; rather than talking about sync failures,
>> let's just state the barrier-based facts.
>>
>> Signed-off-by: Eric Sandeen <sandeen@redhat.com>
>> ---
>>
>> diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c
>> index 75716d3..3d15b28 100644
>> --- a/fs/jbd2/commit.c
>> +++ b/fs/jbd2/commit.c
>> @@ -150,8 +150,8 @@ static int journal_submit_commit_record(journal_t *journal,
>>  	 */
>>  	if (ret == -EOPNOTSUPP && barrier_done) {
>>  		printk(KERN_WARNING
>> -		       "JBD: barrier-based sync failed on %s - "
>> -		       "disabling barriers\n", journal->j_devname);
>> +		       "JBD2: Disabling barriers on %s, "
>> +		       "not supported by device\n", journal->j_devname);
>>  		spin_lock(&journal->j_state_lock);
>>  		journal->j_flags &= ~JBD2_BARRIER;
>>  		spin_unlock(&journal->j_state_lock);
>> @@ -180,8 +180,8 @@ retry:
>>  	wait_on_buffer(bh);
>>  	if (buffer_eopnotsupp(bh) && (journal->j_flags & JBD2_BARRIER)) {
>>  		printk(KERN_WARNING
>> -		       "JBD2: wait_on_commit_record: sync failed on %s - "
>> -		       "disabling barriers\n", journal->j_devname);
>> +		       "JBD2: %s: barriers no longer supported on %s - "
>> +		       "disabling barriers\n", __func__, journal->j_devname);
> 
> Any reason this message has "no longer supported" as opposed to the
> "not supported by device" printed above?

Hm.  In the non-async case, we'd have already tested it in journal_submit_commit_record,
right, and if we failed here, they got lost somehow.

But in the async case, this is the first test we'd get... so maybe
it should just use the same message as the first.

-Eric

> 						- Ted