diff options
| author | Nick Kossifidis <mickflemm@gmail.com> | 2011-11-25 18:40:31 (GMT) |
|---|---|---|
| committer | John W. Linville <linville@tuxdriver.com> | 2011-11-28 19:44:23 (GMT) |
| commit | 9a3916910548e419f4da438406f84af9e05f72eb (patch) | |
| tree | 2b40d8c0eb5467cddb7a8fda615bb4343cd1614f | |
| parent | b4cfb5d574cd9e23e41462061941f6ac68a41c80 (diff) | |
| download | linux-fsl-qoriq-9a3916910548e419f4da438406f84af9e05f72eb.tar.xz | |
ath5k: Optimize ath5k_cw_validate
Optimize ath5k_cw_validate by using the classic (X & (X - 1)) == 0
check to see if a number is power of 2.
v2: Use functions from log2.h instead
Signed-off-by: Nick Kossifidis <mickflemm@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
| -rw-r--r-- | drivers/net/wireless/ath/ath5k/qcu.c | 17 |
1 files changed, 13 insertions, 4 deletions
diff --git a/drivers/net/wireless/ath/ath5k/qcu.c b/drivers/net/wireless/ath/ath5k/qcu.c index e50e64d..30b50f9 100644 --- a/drivers/net/wireless/ath/ath5k/qcu.c +++ b/drivers/net/wireless/ath/ath5k/qcu.c @@ -23,6 +23,7 @@ Queue Control Unit, DCF Control Unit Functions #include "ath5k.h" #include "reg.h" #include "debug.h" +#include <linux/log2.h> /** * DOC: Queue Control Unit (QCU)/DCF Control Unit (DCU) functions @@ -108,13 +109,21 @@ ath5k_hw_release_tx_queue(struct ath5k_hw *ah, unsigned int queue) static u16 ath5k_cw_validate(u16 cw_req) { - u32 cw = 1; cw_req = min(cw_req, (u16)1023); - while (cw < cw_req) - cw = (cw << 1) | 1; + /* Check if cw_req + 1 a power of 2 */ + if (is_power_of_2(cw_req + 1)) + return cw_req; - return cw; + /* Check if cw_req is a power of 2 */ + if (is_power_of_2(cw_req)) + return cw_req - 1; + + /* If none of the above is correct + * find the closest power of 2 */ + cw_req = (u16) roundup_pow_of_two(cw_req) - 1; + + return cw_req; } /** |