sxgbe_sw_reset() is never called in atomic context.
sxgbe_sw_reset() is only called by sxgbe_drv_probe(), which is
only called by sxgbe_platform_probe().
sxgbe_platform_probe() is set as ".probe" in struct platform_driver.
This function is not called in atomic context.
Despite never getting called from atomic context, sxgbe_sw_reset()
calls mdelay() to busily wait.
This is not necessary and can be replaced with usleep_range() to
avoid busy waiting.
This is found by a static analysis tool named DCNS written by myself.
And I also manually check it.
Signed-off-by: Jia-Ju Bai <[email protected]>
---
drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c b/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
index 89831ad..99cd586 100644
--- a/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
+++ b/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
@@ -2038,7 +2038,7 @@ static int sxgbe_sw_reset(void __iomem *addr)
if (!(readl(addr + SXGBE_DMA_MODE_REG) &
SXGBE_DMA_SOFT_RESET))
break;
- mdelay(10);
+ usleep(10000, 11000);
}
if (retry_count < 0)
--
1.9.1
Hi Jia-Ju,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on net-next/master]
[also build test ERROR on v4.16 next-20180411]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Jia-Ju-Bai/net-samsung-sxgbe-Replace-mdelay-with-usleep_range-in-sxgbe_sw_reset/20180411-225900
config: i386-randconfig-x019-201814 (attached as .config)
compiler: gcc-7 (Debian 7.3.0-1) 7.3.0
reproduce:
# save the attached .config to linux build tree
make ARCH=i386
All errors (new ones prefixed by >>):
drivers/net//ethernet/samsung/sxgbe/sxgbe_main.c: In function 'sxgbe_sw_reset':
>> drivers/net//ethernet/samsung/sxgbe/sxgbe_main.c:2039:3: error: implicit declaration of function 'usleep'; did you mean 'ssleep'? [-Werror=implicit-function-declaration]
usleep(10000, 11000);
^~~~~~
ssleep
cc1: some warnings being treated as errors
vim +2039 drivers/net//ethernet/samsung/sxgbe/sxgbe_main.c
2029
2030 static int sxgbe_sw_reset(void __iomem *addr)
2031 {
2032 int retry_count = 10;
2033
2034 writel(SXGBE_DMA_SOFT_RESET, addr + SXGBE_DMA_MODE_REG);
2035 while (retry_count--) {
2036 if (!(readl(addr + SXGBE_DMA_MODE_REG) &
2037 SXGBE_DMA_SOFT_RESET))
2038 break;
> 2039 usleep(10000, 11000);
2040 }
2041
2042 if (retry_count < 0)
2043 return -EBUSY;
2044
2045 return 0;
2046 }
2047
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
Hi Jia-Ju,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on net-next/master]
[also build test ERROR on v4.16 next-20180411]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Jia-Ju-Bai/net-samsung-sxgbe-Replace-mdelay-with-usleep_range-in-sxgbe_sw_reset/20180411-225900
config: i386-randconfig-s1-201814 (attached as .config)
compiler: gcc-6 (Debian 6.4.0-9) 6.4.0 20171026
reproduce:
# save the attached .config to linux build tree
make ARCH=i386
All errors (new ones prefixed by >>):
drivers/net//ethernet/samsung/sxgbe/sxgbe_main.c: In function 'sxgbe_sw_reset':
>> drivers/net//ethernet/samsung/sxgbe/sxgbe_main.c:2039:3: error: implicit declaration of function 'usleep' [-Werror=implicit-function-declaration]
usleep(10000, 11000);
^~~~~~
cc1: some warnings being treated as errors
vim +/usleep +2039 drivers/net//ethernet/samsung/sxgbe/sxgbe_main.c
2029
2030 static int sxgbe_sw_reset(void __iomem *addr)
2031 {
2032 int retry_count = 10;
2033
2034 writel(SXGBE_DMA_SOFT_RESET, addr + SXGBE_DMA_MODE_REG);
2035 while (retry_count--) {
2036 if (!(readl(addr + SXGBE_DMA_MODE_REG) &
2037 SXGBE_DMA_SOFT_RESET))
2038 break;
> 2039 usleep(10000, 11000);
2040 }
2041
2042 if (retry_count < 0)
2043 return -EBUSY;
2044
2045 return 0;
2046 }
2047
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation