| Message ID | 1460665047-24907-1-git-send-email-jacob.e.keller@intel.com |
|---|---|
| State | Accepted |
| Delegated to: | Jeff Kirsher |
| Headers | show |
On Thu, 2016-04-14 at 13:17 -0700, Jacob Keller wrote: > The FM10K_MAX_DATA_PER_TXD is really just using a bitshift as a power > of > 2 operation in an efficient manner. We shouldn't represent this as a > BIT() > because that obscures the intention of the operation. > > Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> > --- > drivers/net/ethernet/intel/fm10k/fm10k.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/net/ethernet/intel/fm10k/fm10k.h > b/drivers/net/ethernet/intel/fm10k/fm10k.h > index fcf106e545c5..e98b86bf0ca1 100644 > --- a/drivers/net/ethernet/intel/fm10k/fm10k.h > +++ b/drivers/net/ethernet/intel/fm10k/fm10k.h > @@ -406,7 +406,7 @@ static inline u16 fm10k_desc_unused(struct > fm10k_ring *ring) > (&(((union fm10k_rx_desc *)((R)->desc))[i])) > > #define FM10K_MAX_TXD_PWR 14 > -#define FM10K_MAX_DATA_PER_TXD BIT(FM10K_MAX_TXD_PWR) > +#define FM10K_MAX_DATA_PER_TXD (1u << FM10K_MAX_TXD_PWR) > > /* Tx Descriptors needed, worst case */ > #define TXD_USE_COUNT(S) DIV_ROUND_UP((S), > FM10K_MAX_DATA_PER_TXD) Note: this *will* cause a checkpatch warning, but as per discussion with Alex, I think this is a false positive. I don't know if there is a good way to fix it? Perhaps we could introduce some sort of "power of 2" macro that would leave in a single place, but I really don't know if that makes a lot of sense. I also am not sure how to make checkpatch.pl avoid the complaints for specific cases such as this. Thanks, Jake
-----Original Message----- From: Intel-wired-lan [mailto:intel-wired-lan-bounces@lists.osuosl.org] On Behalf Of Jacob Keller Sent: Thursday, April 14, 2016 1:17 PM To: Intel Wired LAN <intel-wired-lan@lists.osuosl.org> Subject: [Intel-wired-lan] [PATCH] fm10k: don't use BIT() macro where the value isn't a bitmask The FM10K_MAX_DATA_PER_TXD is really just using a bitshift as a power of 2 operation in an efficient manner. We shouldn't represent this as a BIT() because that obscures the intention of the operation. Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> --- Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
diff --git a/drivers/net/ethernet/intel/fm10k/fm10k.h b/drivers/net/ethernet/intel/fm10k/fm10k.h index fcf106e545c5..e98b86bf0ca1 100644 --- a/drivers/net/ethernet/intel/fm10k/fm10k.h +++ b/drivers/net/ethernet/intel/fm10k/fm10k.h @@ -406,7 +406,7 @@ static inline u16 fm10k_desc_unused(struct fm10k_ring *ring) (&(((union fm10k_rx_desc *)((R)->desc))[i])) #define FM10K_MAX_TXD_PWR 14 -#define FM10K_MAX_DATA_PER_TXD BIT(FM10K_MAX_TXD_PWR) +#define FM10K_MAX_DATA_PER_TXD (1u << FM10K_MAX_TXD_PWR) /* Tx Descriptors needed, worst case */ #define TXD_USE_COUNT(S) DIV_ROUND_UP((S), FM10K_MAX_DATA_PER_TXD)
The FM10K_MAX_DATA_PER_TXD is really just using a bitshift as a power of 2 operation in an efficient manner. We shouldn't represent this as a BIT() because that obscures the intention of the operation. Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> --- drivers/net/ethernet/intel/fm10k/fm10k.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)