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From: Andreas Schwab <schwab@linux-m68k.org>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.cz>, Arnd Bergmann <arnd@arndb.de>,
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        Martin Schwidefsky <schwidefsky@de.ibm.com>
Subject: Re: [resend PATCH for 3.2] procfs: do not confuse jiffies with cputime64_t
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X-Yow: I'm pretending that we're all watching PHIL SILVERS
 instead of RICARDO MONTALBAN!
Date: Thu, 22 Dec 2011 01:20:48 +0100
In-Reply-To: <20111221155922.1d5688a6.akpm@linux-foundation.org> (Andrew
	Morton's message of "Wed, 21 Dec 2011 15:59:22 -0800")
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Andrew Morton <akpm@linux-foundation.org> writes:

> On Thu, 22 Dec 2011 00:55:07 +0100
> Andreas Schwab <schwab@linux-m68k.org> wrote:
>
>> Andrew Morton <akpm@linux-foundation.org> writes:
>> 
>> > Also, in include/asm-generic/cputime.h we have:
>> >
>> > #define usecs_to_cputime64(__msecs)	nsecs_to_jiffies64((__msecs) * 1000)
>> >
>> > But it would be neater to have used nsecs_to_cputime64(), surely.
>> 
>> The procfs interface wants to convert usecs to cputime64, but generic
>> cputime does not have usecs_to_jiffies64.  Once someone writes the
>> latter it can be used here.
>> 
>
> That doesn't address my suggestion.
>
> I'm saying that this:
>
> #define usecs_to_cputime64(__msecs)	nsecs_to_jiffies64((__msecs) * 1000)
>
> should have instead been
>
> #define usecs_to_cputime64(__msecs)	nsecs_to_cputime64((__msecs) * 1000)

It follows the style of the exitsting definitions.  Generic cputime does
not differentiate between jiffies and cputime, so adding a layer of
indirection only here does not increase clarity, IMHO.

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."