Re: [PATCH] nfsd: decrease cl_cb_inflight if fail to queue cb_work

[Benjamin Coddington <bcodding@redhat.com>]

On 21 Feb 2025, at 9:58, Jeff Layton wrote:

> On Fri, 2025-02-21 at 09:46 -0500, Benjamin Coddington wrote:
>> On 21 Feb 2025, at 9:37, Jeff Layton wrote:
>>
>>> On Fri, 2025-02-21 at 09:06 -0500, Benjamin Coddington wrote:
>>>> On 18 Feb 2025, at 9:40, Jeff Layton wrote:
>>>
>>> lease_breaking() is only checked when want_write is false. IOW, if
>>> you're breaking the lease for write, then lm_break is always called.
>>>
>>> Is that a bug or a feature? I'm not sure, but it's been that way since
>>> ~2011.
>>
>> Yeah.. why?
>>
>> Thanks I missed that detail when I refreshed my memory of it just now.
>> Seems like you'd want to avoid constantly calling lm_break for both cases,
>> spamming the lock manager adds nothing.  2 cents.
>>
>
> Sorry, it doesn't get called every time. If want_write is called then
> we _do_ check FL_UNLOCK_PENDING. IOW, you can get a downgrade attempt
> first, and then a full unlock request later.
>
> nfsd doesn't do downgrades. It recalls the object either way. So,
> ignoring subsequent lm_break calls is the right thing to do, I think.

Got it, thanks for clarifying this behavior for me!

Ben