2015-05-25 06:26:38

by Nicholas Mc Guire

Subject: [PATCH V2] irda: use msecs_to_jiffies for conversion to jiffies

API compliance scanning with coccinelle flagged:
./net/irda/timer.c:63:35-37: use of msecs_to_jiffies probably perferable

Converting milliseconds to jiffies by "val * HZ / 1000" technically
is not a clean solution as it does not handle all corner cases correctly.
By changing the conversion to use msecs_to_jiffies(val) conversion is
correct in all cases. Further the () around the arithmetic expression
was dropped.

Patch was compile tested for x86_64_defconfig + CONFIG_IRDA=m

Patch is against 4.1-rc4 (localversion-next is -next-20150522)

Signed-off-by: Nicholas Mc Guire <[email protected]>
---

V2: botched prefix in the subject line updated to irda: thanks
to David Miller <[email protected]>

Should the Status note at the top of the file be updated ? it seems
the file has been marked experimental since at least 1999 ?

net/irda/timer.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/irda/timer.c b/net/irda/timer.c
index 0c4c115..f2280f7 100644
--- a/net/irda/timer.c
+++ b/net/irda/timer.c
@@ -60,8 +60,8 @@ void irlap_start_query_timer(struct irlap_cb *self, int S, int s)
* to avoid messing with for incoming connections requests and
* to accommodate devices that perform discovery slower than us.
* Jean II */
- timeout = ((sysctl_slot_timeout * HZ / 1000) * (S - s)
- + XIDEXTRA_TIMEOUT + SMALLBUSY_TIMEOUT);
+ timeout = msecs_to_jiffies(sysctl_slot_timeout) * (S - s)
+ + XIDEXTRA_TIMEOUT + SMALLBUSY_TIMEOUT;

/* Set or re-set the timer. We reset the timer for each received
* discovery query, which allow us to automatically adjust to
--
1.7.10.4

2015-05-25 21:46:43

by David Miller

Subject: Re: [PATCH V2] irda: use msecs_to_jiffies for conversion to jiffies

From: Nicholas Mc Guire <[email protected]>
Date: Mon, 25 May 2015 08:16:50 +0200

> API compliance scanning with coccinelle flagged:
> ./net/irda/timer.c:63:35-37: use of msecs_to_jiffies probably perferable
>
> Converting milliseconds to jiffies by "val * HZ / 1000" technically
> is not a clean solution as it does not handle all corner cases correctly.
> By changing the conversion to use msecs_to_jiffies(val) conversion is
> correct in all cases. Further the () around the arithmetic expression
> was dropped.
>
> Patch was compile tested for x86_64_defconfig + CONFIG_IRDA=m
>
> Patch is against 4.1-rc4 (localversion-next is -next-20150522)
>
> Signed-off-by: Nicholas Mc Guire <[email protected]>

Applied, thank you.