linux-kernel - Re: [PATCH v7 3/8] time: Remove duplicated code in ktime_get_raw_and

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Message-ID: <20160216075210.GA2461@localhost.localdomain>
Date:	Tue, 16 Feb 2016 08:52:10 +0100
From:	Richard Cochran <richardcochran@...il.com>
To:	"Christopher S. Hall" <christopher.s.hall@...el.com>
Cc:	tglx@...utronix.de, mingo@...hat.com, john.stultz@...aro.org,
	hpa@...or.com, jeffrey.t.kirsher@...el.com, x86@...nel.org,
	linux-kernel@...r.kernel.org, intel-wired-lan@...ts.osuosl.org,
	netdev@...r.kernel.org, kevin.b.stanton@...el.com,
	kevin.j.clarke@...el.com
Subject: Re: [PATCH v7 3/8] time: Remove duplicated code in
 ktime_get_raw_and_real()

On Fri, Feb 12, 2016 at 12:25:24PM -0800, Christopher S. Hall wrote:
> The code in ktime_get_snapshot() is a superset of the code in
> ktime_get_raw_and_real() code. Further, ktime_get_raw_and_real() is
> called only by the PPS code, pps_get_ts(). Consolidate the
> pps_get_ts() code into a single function calling ktime_get_snapshot()
> and eliminate ktime_get_raw_and_real(). A side effect of this is that
> the raw and real results of pps_get_ts() correspond to exactly the
> same clock cycle. Previously these values represented separate reads
> of the system clock.

Nice improvement.

> @@ -888,6 +888,8 @@ void ktime_get_snapshot(struct system_time_snapshot *systime_snapshot)
>  	s64 nsec_real;
>  	cycle_t now;
>  
> +	WARN_ON(timekeeping_suspended);
...
> -	WARN_ON_ONCE(timekeeping_suspended);

Is this change intentional?

Thanks,
Richard