Re: [PATCH] crypto: hisilicon - check if debugfs opened

[tanghui20]

On 2021/3/28 23:09, Greg KH wrote:
> On Sat, Mar 27, 2021 at 04:33:00PM +0800, Hui Tang wrote:
> > 'xx_debugfs_init' check if debugfs opened.
> >
> > Signed-off-by: Hui Tang <tanghui20@xxxxxxxxxx>
> > ---
> >  drivers/crypto/hisilicon/hpre/hpre_main.c | 5 ++++-
> >  drivers/crypto/hisilicon/qm.c             | 3 +++
> >  drivers/crypto/hisilicon/sec2/sec_main.c  | 5 ++++-
> >  drivers/crypto/hisilicon/zip/zip_main.c   | 3 +++
> >  4 files changed, 14 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/crypto/hisilicon/hpre/hpre_main.c b/drivers/crypto/hisilicon/hpre/hpre_main.c
> > index c7ab06d..f2605c4 100644
> > --- a/drivers/crypto/hisilicon/hpre/hpre_main.c
> > +++ b/drivers/crypto/hisilicon/hpre/hpre_main.c
> > @@ -779,6 +779,9 @@ static int hpre_debugfs_init(struct hisi_qm *qm)
> >  	struct device *dev = &qm->pdev->dev;
> >  	int ret;
> >
> > +	if (!debugfs_initialized())
> > +		return -ENOENT;
>
> Why?  What does this help with?  Why does the code care if debugfs is
> running or not?
When !CONFIG_DEBUG_FS, there is no problem if debugfs is not checked,
but if checking debugfs, a series of stub functions of debugfs can be
skipped and 'xx_debugfs_init' will be return immediately.

Thanks.