From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Boyd Subject: Re: mmotm 2013-08-27-16-51 uploaded Date: Wed, 28 Aug 2013 11:42:20 -0700 Message-ID: <20130828184218.GB19754@codeaurora.org> References: <20130827235227.99DB95A41D6@corp2gmr1-2.hot.corp.google.com> <521D494F.1010507@codeaurora.org> <20130827182616.f9396ed6.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20130827182616.f9396ed6.akpm@linux-foundation.org> Sender: owner-linux-mm@kvack.org To: Andrew Morton Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-next@vger.kernel.org, voice.shen@atmel.com, Russell King - ARM Linux List-Id: linux-next.vger.kernel.org On 08/27, Andrew Morton wrote: > On Tue, 27 Aug 2013 17:50:23 -0700 Stephen Boyd wrote: > > > On 08/27/13 16:52, akpm@linux-foundation.org wrote: > > > * kernel-time-sched_clockc-correct-the-comparison-parameter-of-mhz.patch > > > > > > > I believe Russell nacked this change[1]? This should probably be dropped > > unless there's been more discussion. Or maybe reworked into a comment in > > the code that doesn't lead to the same change again. > > > > [1] https://lkml.org/lkml/2013/8/7/95 > > Well OK, but the code looks totally wrong. Care to send a comment patch > so the next confused person doesn't "fix" it? Sure, how about this? ---8<---- From: Stephen Boyd Subject: [PATCH] sched_clock: Document 4Mhz vs 1Mhz decision Bo Shen sent a patch to change this to 1Mhz instead of 4Mhz but according to Russell King the use of 4Mhz was intentional. Add a comment to this effect so that others don't try to change the code as well. Signed-off-by: Stephen Boyd --- kernel/time/sched_clock.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/kernel/time/sched_clock.c b/kernel/time/sched_clock.c index a326f27..1e9e298 100644 --- a/kernel/time/sched_clock.c +++ b/kernel/time/sched_clock.c @@ -128,6 +128,10 @@ void __init setup_sched_clock(u32 (*read)(void), int bits, unsigned long rate) clocks_calc_mult_shift(&cd.mult, &cd.shift, rate, NSEC_PER_SEC, 0); r = rate; + /* + * Use 4MHz instead of 1MHz so that things like 1.832Mhz show as + * 1832Khz + */ if (r >= 4000000) { r /= 1000000; r_unit = 'M'; -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, hosted by The Linux Foundation -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org