Re: [PATCH 2/4] Staging: ks7010: hostif: Fix multiple use of arguments in SME queue macros.

From: Greg KH
Date: Mon Feb 19 2018 - 12:09:10 EST


On Fri, Feb 16, 2018 at 06:25:01PM -0800, Quytelda Kahja wrote:
> Use GCC extensions to prevent macro arguments from accidentally being evaluated
> multiple times when the macro is called.
>
> Signed-off-by: Quytelda Kahja <quytelda@xxxxxxxxxxx>
> ---
> drivers/staging/ks7010/ks_hostif.c | 19 +++++++++++++------
> 1 file changed, 13 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/staging/ks7010/ks_hostif.c b/drivers/staging/ks7010/ks_hostif.c
> index 975dbbb3abd0..30c9592b3a00 100644
> --- a/drivers/staging/ks7010/ks_hostif.c
> +++ b/drivers/staging/ks7010/ks_hostif.c
> @@ -22,12 +22,19 @@
> #include <net/iw_handler.h> /* New driver API */
>
> /* macro */
> -#define inc_smeqhead(priv) \
> - (priv->sme_i.qhead = (priv->sme_i.qhead + 1) % SME_EVENT_BUFF_SIZE)
> -#define inc_smeqtail(priv) \
> - (priv->sme_i.qtail = (priv->sme_i.qtail + 1) % SME_EVENT_BUFF_SIZE)
> -#define cnt_smeqbody(priv) \
> - (((priv->sme_i.qtail + SME_EVENT_BUFF_SIZE) - (priv->sme_i.qhead)) % SME_EVENT_BUFF_SIZE)
> +#define inc_smeqhead(priv) \
> + ({ typeof(priv) priv_ = (priv); \
> + unsigned int next_qhead = priv_->sme_i.qhead + 1; \
> + priv_->sme_i.qhead = next_qhead % SME_EVENT_BUFF_SIZE; })

No need, just make these real functions please.

thanks,

greg k-h