On Tue, Mar 30, 2021 at 08:09:46PM +0800, tanghui20 wrote: > > > 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. And have you measured an actual speed difference for that? I would be amazed if you could... thanks, greg k-h