Re: [RFC PATCH v3 0/9] Suppress negative dentry

[Amir Goldstein <amir73il@gmail.com>]

On Fri, May 15, 2020 at 10:21 AM Chengguang Xu <cgxu519@mykernel.net> wrote:
>
> This series adds a new lookup flag LOOKUP_DONTCACHE_NEGATIVE
> to indicate to drop negative dentry in slow path of lookup.
>
> In overlayfs, negative dentries in upper/lower layers are useless
> after construction of overlayfs' own dentry, so in order to
> effectively reclaim those dentries, specify LOOKUP_DONTCACHE_NEGATIVE
> flag when doing lookup in upper/lower layers.
>
> Patch 1 adds flag LOOKUP_DONTCACHE_NEGATIVE and related logic in vfs layer.
> Patch 2 does lookup optimazation for overlayfs.
> Patch 3-9 just adjusts function argument when calling
> lookup_positive_unlocked() and lookup_one_len_unlocked().

Hmm you cannot do that, build must not be broken mid series.
When Miklos said split he meant to patch 1 and 2.
Patch 1 must convert all callers to the new argument list,
at which point all overlayfs calls are with 0 flags.

Once that's done, you may add:
Reviewed-by: Amir Goldstein <amir73il@gmail.com>

Thanks,
Amir.