From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932457Ab1AKRYP (ORCPT ); Tue, 11 Jan 2011 12:24:15 -0500 Received: from e7.ny.us.ibm.com ([32.97.182.137]:59439 "EHLO e7.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754023Ab1AKRYN (ORCPT ); Tue, 11 Jan 2011 12:24:13 -0500 Subject: Re: [PATCH] clocks_calc_mult_shift(): rename minsec argument according to actual usage From: john stultz To: Nicolas Pitre , Thomas Gleixner Cc: lkml In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Date: Tue, 11 Jan 2011 09:24:04 -0800 Message-ID: <1294766644.3441.9.camel@work-vm> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 Content-Transfer-Encoding: 7bit X-Content-Scanned: Fidelis XPS MAILER Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2011-01-11 at 12:18 -0500, Nicolas Pitre wrote: > The minsec argument to clocks_calc_mult_shift() is misnamed. It is used > to clamp the magnitude of the mult factor so that a multiplication with > any value in the given range won't overflow a 64 bit result. Let's > rename it to match the actual usage. > > Signed-off-by: Nicolas Pitre Acked-by: John Stultz Thomas, mind picking this up for 2.6.38? thanks -john > diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c > index c18d7ef..8588abc 100644 > --- a/kernel/time/clocksource.c > +++ b/kernel/time/clocksource.c > @@ -113,7 +113,7 @@ EXPORT_SYMBOL_GPL(timecounter_cyc2time); > * @shift: pointer to shift variable > * @from: frequency to convert from > * @to: frequency to convert to > - * @minsec: guaranteed runtime conversion range in seconds > + * @maxsec: guaranteed runtime conversion range in seconds > * > * The function evaluates the shift/mult pair for the scaled math > * operations of clocksources and clockevents. > @@ -122,7 +122,7 @@ EXPORT_SYMBOL_GPL(timecounter_cyc2time); > * NSEC_PER_SEC == 1GHz and @from is the counter frequency. For clock > * event @to is the counter frequency and @from is NSEC_PER_SEC. > * > - * The @minsec conversion range argument controls the time frame in > + * The @maxsec conversion range argument controls the time frame in > * seconds which must be covered by the runtime conversion with the > * calculated mult and shift factors. This guarantees that no 64bit > * overflow happens when the input value of the conversion is > @@ -131,7 +131,7 @@ EXPORT_SYMBOL_GPL(timecounter_cyc2time); > * factors. > */ > void > -clocks_calc_mult_shift(u32 *mult, u32 *shift, u32 from, u32 to, u32 minsec) > +clocks_calc_mult_shift(u32 *mult, u32 *shift, u32 from, u32 to, u32 maxsec) > { > u64 tmp; > u32 sft, sftacc= 32; > @@ -140,7 +140,7 @@ clocks_calc_mult_shift(u32 *mult, u32 *shift, u32 from, u32 to, u32 minsec) > * Calculate the shift factor which is limiting the conversion > * range: > */ > - tmp = ((u64)minsec * from) >> 32; > + tmp = ((u64)maxsec * from) >> 32; > while (tmp) { > tmp >>=1; > sftacc--;