Re: [RFC] fs: Avoid to use lockdep information if it's turned off

[David Sterba]

On Thu, Nov 12, 2020 at 11:22:12AM +0800, Boqun Feng wrote:
> For the "BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low!" warning, do you see
> that every time when you run xfstests and don't see other lockdep
> splats? If so, that means we reach the limitation of number of lockdep
> hlock chains, and we should fix that.

It's not every time and depends on the release, eg. I found no reports
in a sample log for 5.7..5.9, while there are many for 5.2..5.6 and
5.10, every 2nd or 3rd run.

[    0.185150] ... MAX_LOCKDEP_SUBCLASSES:  8
[    0.186202] ... MAX_LOCK_DEPTH:          48
[    0.187286] ... MAX_LOCKDEP_KEYS:        8192
[    0.188404] ... CLASSHASH_SIZE:          4096
[    0.189519] ... MAX_LOCKDEP_ENTRIES:     32768
[    0.190672] ... MAX_LOCKDEP_CHAINS:      65536
[    0.191814] ... CHAINHASH_SIZE:          32768