2022-02-20 20:47:49

by Junwen Wu

Subject: [PATCH] net: ksz884x: use time_before in netdev_open for compatibility

use time_before instead of direct compare for compatibility

Signed-off-by: wudaemon <[email protected]>
---
drivers/net/ethernet/micrel/ksz884x.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/micrel/ksz884x.c b/drivers/net/ethernet/micrel/ksz884x.c
index d024983815da..fd3cb9ce438f 100644
--- a/drivers/net/ethernet/micrel/ksz884x.c
+++ b/drivers/net/ethernet/micrel/ksz884x.c
@@ -5428,7 +5428,7 @@ static int netdev_open(struct net_device *dev)
if (rc)
return rc;
for (i = 0; i < hw->mib_port_cnt; i++) {
- if (next_jiffies < jiffies)
+ if (time_before(next_jiffies, jiffies))
next_jiffies = jiffies + HZ * 2;
else
next_jiffies += HZ * 1;
--
2.25.1

2022-02-23 01:42:21

by Jakub Kicinski

Subject: Re: [PATCH] net: ksz884x: use time_before in netdev_open for compatibility

On Sun, 20 Feb 2022 12:21:01 +0000 wudaemon wrote:
> use time_before instead of direct compare for compatibility
>
> Signed-off-by: wudaemon <[email protected]>
> ---
> drivers/net/ethernet/micrel/ksz884x.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/micrel/ksz884x.c b/drivers/net/ethernet/micrel/ksz884x.c
> index d024983815da..fd3cb9ce438f 100644
> --- a/drivers/net/ethernet/micrel/ksz884x.c
> +++ b/drivers/net/ethernet/micrel/ksz884x.c
> @@ -5428,7 +5428,7 @@ static int netdev_open(struct net_device *dev)
> if (rc)
> return rc;
> for (i = 0; i < hw->mib_port_cnt; i++) {
> - if (next_jiffies < jiffies)
> + if (time_before(next_jiffies, jiffies))
> next_jiffies = jiffies + HZ * 2;
> else
> next_jiffies += HZ * 1;

I think this code is trying to space out the updates in time.
So neither way of doing the comparison seems great.
It'd be better to remove the static next_jiffies variable,
and just do something more akin to what mib_read_work() does
in open() as well.

2022-02-24 16:45:31

by Jakub Kicinski

Subject: Re: [PATCH] net: ksz884x: use time_before in netdev_open for compatibility

On Thu, 24 Feb 2022 22:16:28 +0800 (CST) 吴俊文 wrote:
> Hi ,Jakub .I have changed my patch as your advise as follows:
> diff --git a/drivers/net/ethernet/micrel/ksz884x.c b/drivers/net/ethernet/micrel/ksz884x.c index 7dc451f..443d7bc 100644 --- a/drivers/net/ethernet/micrel/ksz884x.c +++ b/drivers/net/ethernet/micrel/ksz884x.c @@ -5301,7 +5301,6 @@ static irqreturn_t netdev_intr(int irq, void *dev_id) * Linux network device functions */ -static unsigned long next_jiffies; #ifdef CONFIG_NET_POLL_CONTROLLER static void netdev_netpoll(struct net_device *dev) @@ -5492,7 +5491,7 @@ static int netdev_open(struct net_device *dev) int i; int p; int rc = 0; - + unsigned long next_jiffies=0 priv->multicast = 0; priv->promiscuous = 0; @@ -5506,7 +5505,7 @@ static int netdev_open(struct net_device *dev) if (rc) return rc; for (i = 0; i < hw->mib_port_cnt; i++) { - if (next_jiffies < jiffies) + if (time_before(next_jiffies, jiffies)) next_jiffies = jiffies + HZ * 2; else next_jiffies += HZ * 1; @@ -6642,7 +6641,7 @@ static void mib_read_work(struct work_struct *work) struct ksz_port_mib *mib; int i; - next_jiffies = jiffies; + unsigned long next_jiffies = jiffies; for (i = 0; i < hw->mib_port_cnt; i++) { mib = &hw->port_mib[i];
>
> Do you have any other advise ?Thanks

Sorry your patch got scrambled into a single line and encoded with HTML.
Feel free to post it with git as [PATCH v2] and we'll take it from
there.