2018-01-26 15:29:44

by Jia-Ju Bai

[permalink] [raw]
Subject: [PATCH 1/3] block: mtip32xx: Replace mdelay with msleep in mtip_hw_init

After checking all possible call chains to mtip_hw_init() here,
my tool finds that this function is never called in atomic context,
namely never in an interrupt handler or holding a spinlock.
And mtip_hw_init() calls kzalloc_node(GFP_KERNEL) that can sleep,
so it indicates that mtip_hw_init() can call functions that can sleep.
Thus mdelay can be replaced with msleep to avoid busy wait.

This is found by a static analysis tool named DCNS written by myself.

Signed-off-by: Jia-Ju Bai <[email protected]>
---
drivers/block/mtip32xx/mtip32xx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
index b8af735..1d8ace6 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -3069,7 +3069,7 @@ static int mtip_hw_init(struct driver_data *dd)
timeout = jiffies + msecs_to_jiffies(30000);
while (((readl(dd->port->mmio + PORT_SCR_STAT) & 0x0F) != 0x03) &&
time_before(jiffies, timeout)) {
- mdelay(100);
+ msleep(100);
}
if (unlikely(mtip_check_surprise_removal(dd->pdev))) {
timetaken = jiffies - timetaken;
--
1.7.9.5