From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org (ozlabs.org [IPv6:2401:3900:2:1::2]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3yblFr4pLTzDqpF for ; Tue, 14 Nov 2017 22:12:00 +1100 (AEDT) In-Reply-To: <20170823185841.25286-1-svaidy@linux.vnet.ibm.com> To: Vaidyanathan Srinivasan From: Michael Ellerman Cc: Michael Neuling , linuxppc-dev@lists.ozlabs.org, Anton Blanchard Subject: Re: powerpc/powernv/idle: Round up latency and residency values Message-Id: <3yblFr32fbz9t0F@ozlabs.org> Date: Tue, 14 Nov 2017 22:12:00 +1100 (AEDT) List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, 2017-08-23 at 18:58:41 UTC, Vaidyanathan Srinivasan wrote: > On PowerNV platforms, firmware provides exit latency and > target residency for each of the idle states in nano > seconds. Cpuidle framework expects the values in micro > seconds. Round up to nearest micro seconds to avoid errors > in cases where the values are defined as fractional micro > seconds. > > Default idle state of 'snooze' has exit latency of zero. If > other states have fractional micro second exit latency, they > would get rounded down to zero micro second and make cpuidle > framework choose deeper idle state when snooze loop is the > right choice. > > Reported-by: Anton Blanchard > Signed-off-by: Vaidyanathan Srinivasan > Reviewed-by: Gautham R. Shenoy Applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/8d4e10e9ed9450e18fbbf6a8872be0 cheers