Re: nfsd grace period open owners

[Bryan Schumaker <bjschuma@netapp.com>]

On 09/28/2011 02:23 PM, J. Bruce Fields wrote:
> On Wed, Sep 28, 2011 at 02:06:16PM -0400, Bryan Schumaker wrote:
>> Hi Bruce,
>>
>> I'm updating my fault injection patches to work with your recent stateid changes, and I had a question about something I'm seeing on the server.  When I reboot the server it will enter a grace period and reply to any OPEN requests from the client with NFSERR_GRACE.  I used Wireshark to see that NFSERR_GRACE is returned 12 times before the open succeeds, so 13 OPEN requests total.  When I send the command to forget all open owners I find that 13 open owners have been forgotten, but I only expecting to find 1.  Is this what you would expect the server to do?
> 
> Huh.  No, that doesn't sound right.  A failed open doesn't confirm the
> openowner, and I don't think there's any reason to keep around an
> unconfirmed openowner.

Makes sense to me.

> 
> Out of curiosity, is the client using a different openowner for each
> open?

Yeah, looks like the client is using a different one for each attempt.

- Bryan

> 
> --b.
> 
>>
>> I've pasted the code I use to count and delete open owners below.  The variable "num" has the value 0, so all open owners should be deleted.
>>
>> - Bryan
>>
>> static int nfsd_forget_n_openowners(u64 num)
>> {
>> 	int i, count = 0;
>> 	struct nfs4_stateowner *sop, *next;
>>
>> 	for (i = 0; i < OPEN_OWNER_HASH_SIZE; i++) {
>> 		list_for_each_entry_safe(sop, next, &open_ownerstr_hashtbl[i], so_strhash) {
>> 			release_openowner(openowner(sop));
>> 			if (++count == num)
>> 				return count;
>> 		}
>> 	}
>> 	return count;
>> }
>>
>> void nfsd_forget_openowners(u64 num)
>> {
>> 	int count;
>>
>> 	nfs4_lock_state();
>> 	count = nfsd_forget_n_openowners(num);
>> 	nfs4_unlock_state();
>>
>> 	printk(KERN_INFO "%s %s Forgot %d open owners", __FILE__, __func__, count);
>> }