+ timekeeping-use-time_is_before_jiffies-instead-of-open-coding-it.patch added to -mm tree

+ timekeeping-use-time_is_before_jiffies-instead-of-open-coding-it.patch added to -mm tree

[Andrew Morton]

The patch titled
     Subject: timekeeping: use time_is_before_jiffies() instead of open coding it
has been added to the -mm tree.  Its filename is
     timekeeping-use-time_is_before_jiffies-instead-of-open-coding-it.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/timekeeping-use-time_is_before_jiffies-instead-of-open-coding-it.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/timekeeping-use-time_is_before_jiffies-instead-of-open-coding-it.patch

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------------------------------------------------------
From: Wang Qing <wangqing@vivo.com>
Subject: timekeeping: use time_is_before_jiffies() instead of open coding it

Use the helper function time_is_{before,after}_jiffies() to improve code
readability.

Link: https://lkml.kernel.org/r/1650621172-66967-10-git-send-email-wangqing@vivo.com
Signed-off-by: Wang Qing <wangqing@vivo.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 kernel/time/timekeeping.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/kernel/time/timekeeping.c~timekeeping-use-time_is_before_jiffies-instead-of-open-coding-it
+++ a/kernel/time/timekeeping.c
@@ -216,7 +216,7 @@ static void timekeeping_check_update(str
 	}
 
 	if (tk->underflow_seen) {
-		if (jiffies - tk->last_warning > WARNING_FREQ) {
+		if (time_is_before_jiffies(tk->last_warning + WARNING_FREQ)) {
 			printk_deferred("WARNING: Underflow in clocksource '%s' observed, time update ignored.\n", name);
 			printk_deferred("         Please report this, consider using a different clocksource, if possible.\n");
 			printk_deferred("         Your kernel is probably still fine.\n");
@@ -226,7 +226,7 @@ static void timekeeping_check_update(str
 	}
 
 	if (tk->overflow_seen) {
-		if (jiffies - tk->last_warning > WARNING_FREQ) {
+		if (time_is_before_jiffies(tk->last_warning + WARNING_FREQ)) {
 			printk_deferred("WARNING: Overflow in clocksource '%s' observed, time update capped.\n", name);
 			printk_deferred("         Please report this, consider using a different clocksource, if possible.\n");
 			printk_deferred("         Your kernel is probably still fine.\n");
_

Patches currently in -mm which might be from wangqing@vivo.com are

block-xen-use-time_is_before_eq_jiffies-instead-of-open-coding-it.patch
gpu-drm-i915-use-time_is_after_jiffies-instead-of-open-coding-it.patch
gpu-drm-radeon-use-time_is_before_jiffies-instead-of-open-coding-it.patch
hid-use-time_is_after_jiffies-instead-of-open-coding-it.patch
md-use-time_is_before_eq_jiffies-instead-of-open-coding-it.patch
net-wireless-marvell-use-time_is_before_jiffies-instead-of-open-coding-it.patch
scsi-bfa-use-time_is_before_jiffies-instead-of-open-coding-it.patch
timekeeping-use-time_is_before_jiffies-instead-of-open-coding-it.patch
net-decnet-use-time_is_before_jiffies-instead-of-open-coding-it.patch

Re: + timekeeping-use-time_is_before_jiffies-instead-of-open-coding-it.patch added to -mm tree

[Thomas Gleixner]

On Fri, Apr 22 2022 at 13:37, Andrew Morton wrote:
> From: Wang Qing <wangqing@vivo.com>
> Subject: timekeeping: use time_is_before_jiffies() instead of open coding it
>
> Use the helper function time_is_{before,after}_jiffies() to improve code
> readability.
>
> Link: https://lkml.kernel.org/r/1650621172-66967-10-git-send-email-wangqing@vivo.com
> Signed-off-by: Wang Qing <wangqing@vivo.com>
> Cc: John Stultz <john.stultz@linaro.org>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Stephen Boyd <sboyd@kernel.org>
> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
> ---
>
>  kernel/time/timekeeping.c |    4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> --- a/kernel/time/timekeeping.c~timekeeping-use-time_is_before_jiffies-instead-of-open-coding-it
> +++ a/kernel/time/timekeeping.c
> @@ -216,7 +216,7 @@ static void timekeeping_check_update(str
>  	}
>  
>  	if (tk->underflow_seen) {
> -		if (jiffies - tk->last_warning > WARNING_FREQ) {
> +		if (time_is_before_jiffies(tk->last_warning + WARNING_FREQ)) {

I have a hard time to see how this improves anything. The least thing it
improves is readability.

Yeah, I know some script told so....

Thanks,

        tglx