Re: [PATCH v3 3/4] 9p: Set default negative dentry retention time for cache=loose

From: Christian Schoenebeck

Date: Wed Mar 04 2026 - 07:55:14 EST


On Friday, 27 February 2026 08:56:54 CET Remi Pommarel wrote:
> For cache=loose mounts, set the default negative dentry cache retention
> time to 24 hours.
>
> Signed-off-by: Remi Pommarel <repk@xxxxxxxxxxxx>
> ---
> fs/9p/v9fs.c | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/fs/9p/v9fs.c b/fs/9p/v9fs.c
> index a26bd9070786..d14f6eda94d6 100644
> --- a/fs/9p/v9fs.c
> +++ b/fs/9p/v9fs.c
> @@ -24,6 +24,9 @@
> #include "v9fs_vfs.h"
> #include "cache.h"
>
> +/* cache=loose default negative dentry retention time is 24hours */
> +#define CACHE_LOOSE_NDENTRY_TMOUT_DEFAULT (24 * 60 * 60 * 1000)
> +

Come on, really worth to save 4 characters here as well? :)

Whatever:

Reviewed-by: Christian Schoenebeck <linux_oss@xxxxxxxxxxxxx>

> static DEFINE_SPINLOCK(v9fs_sessionlist_lock);
> static LIST_HEAD(v9fs_sessionlist);
> struct kmem_cache *v9fs_inode_cache;
> @@ -440,6 +443,13 @@ static void v9fs_apply_options(struct v9fs_session_info
> *v9ses, v9ses->uid = ctx->session_opts.uid;
> v9ses->session_lock_timeout = ctx->session_opts.session_lock_timeout;
> v9ses->ndentry_timeout_ms = ctx->session_opts.ndentry_timeout_ms;
> +
> + /* If negative dentry timeout has not been overriden set default for
> + * cache=loose
> + */
> + if (!(v9ses->flags & V9FS_NDENTRY_TMOUT_SET) &&
> + (v9ses->cache & CACHE_LOOSE))
> + v9ses->ndentry_timeout_ms = CACHE_LOOSE_NDENTRY_TMOUT_DEFAULT;
> }
>
> /**