Re: [PATCH v2 06/50] primitives for maintaining persisitency

James Bottomley
2025-10-28T12:38:02Z

On Tue, 2025-10-28 at 00:45 +0000, Al Viro wrote:
[...]
> +void d_make_discardable(struct dentry *dentry)
> +{
> + spin_lock(&dentry->d_lock);
> + dentry->d_flags &= ~DCACHE_PERSISTENT;
> + dentry->d_lockref.count--;
> + rcu_read_lock();
> + finish_dput(dentry);
> +}
> +EXPORT_SYMBOL(d_make_discardable);

I was going to ask why you don't have a WARN_ON if the dentry is not
persistent here. Fortunately I read the next patch which gives the
explanation and saw that you do do this in patch 50. For those of us
who have a very linear way of reading and responding to patches, it
would have been helpful to put a comment at the top saying something
like persistency will be checked when all callers are converted, which
you can replace in patch 50.

Regards,

James