Re: [PATCH] nfs: pnfs: use GFP_ATOMIC under spin lock

From: Trond Myklebust
Date: Mon Jun 29 2020 - 17:02:31 EST


On Mon, 2020-06-29 at 14:21 +0800, Xu Wang wrote:
> A spin lock is taken here so we should use GFP_ATOMIC.
>
> Signed-off-by: Xu Wang <vulab@xxxxxxxxxxx>
> ---
> fs/nfs/pnfs.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
> index dd2e14f5875d..d84c1b7b71d2 100644
> --- a/fs/nfs/pnfs.c
> +++ b/fs/nfs/pnfs.c
> @@ -2170,7 +2170,7 @@ _pnfs_grab_empty_layout(struct inode *ino,
> struct nfs_open_context *ctx)
> struct pnfs_layout_hdr *lo;
>
> spin_lock(&ino->i_lock);
> - lo = pnfs_find_alloc_layout(ino, ctx, GFP_KERNEL);
> + lo = pnfs_find_alloc_layout(ino, ctx, GFP_ATOMIC);
> if (!lo)
> goto out_unlock;
> if (!test_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags))

NACK. Please read the code before sending yet another one of these
pointless patches.

--
Trond Myklebust
Linux NFS client maintainer, Hammerspace
trond.myklebust@xxxxxxxxxxxxxxx