2018-04-10 12:33:31

by Jia-Ju Bai

[permalink] [raw]
Subject: [PATCH 6/6] staging: rtl8192u: Replace mdelay with usleep_range in dm_TXPowerTrackingCallback_TSSI

dm_TXPowerTrackingCallback_TSSI() is never called in atomic context.

dm_TXPowerTrackingCallback_TSSI() is only called by
dm_txpower_trackingcallback(), which is set a parameter of
INIT_DELAYED_WORK() in rtl8192_init_priv_task().

Despite never getting called from atomic context,
dm_TXPowerTrackingCallback_TSSI() 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/staging/rtl8192u/r8192U_dm.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/rtl8192u/r8192U_dm.c b/drivers/staging/rtl8192u/r8192U_dm.c
index e6f8d1d..51b2516 100644
--- a/drivers/staging/rtl8192u/r8192U_dm.c
+++ b/drivers/staging/rtl8192u/r8192U_dm.c
@@ -538,13 +538,13 @@ static void dm_TXPowerTrackingCallback_TSSI(struct net_device *dev)
rtStatus = SendTxCommandPacket(dev, &tx_cmd, 12);
if (rtStatus == RT_STATUS_FAILURE)
RT_TRACE(COMP_POWER_TRACKING, "Set configuration with tx cmd queue fail!\n");
- mdelay(1);
+ usleep_range(1000, 2000);
/*DbgPrint("hi, vivi, strange\n");*/
for (i = 0; i <= 30; i++) {
read_nic_byte(dev, 0x1ba, &Pwr_Flag);

if (Pwr_Flag == 0) {
- mdelay(1);
+ usleep_range(1000, 2000);
continue;
}
read_nic_word(dev, 0x13c, &Avg_TSSI_Meas);
--
1.9.1