Re: [PATCH 1/5] locking: Add rwsem_is_write_locked()

From: Matthew Wilcox
Date: Tue Sep 12 2023 - 08:29:07 EST


On Tue, Sep 12, 2023 at 11:03:42AM +0200, Peter Zijlstra wrote:
> If not, then sure we can do this; it's not like I managed to get rid of
> muteX_is_locked() -- and I actually tried at some point :/
>
> And just now I grepped for it, and look what I find:
>
> drivers/hid/hid-nintendo.c: if (unlikely(mutex_is_locked(&ctlr->output_mutex))) {
> drivers/nvdimm/btt.c: if (mutex_is_locked(&arena->err_lock)
>
> And there's more :-(

Are these actually abuse? I looked at these two, and they both seem to
be asking "Does somebody else currently have this mutex?" rather than
"Do I have this mutex?".