Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752532AbcDKGTA (ORCPT ); Mon, 11 Apr 2016 02:19:00 -0400 Received: from mga01.intel.com ([192.55.52.88]:10158 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752282AbcDKGSn (ORCPT ); Mon, 11 Apr 2016 02:18:43 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.24,462,1455004800"; d="scan'208";a="929706689" From: Yuyang Du To: peterz@infradead.org, mingo@kernel.org, linux-kernel@vger.kernel.org Cc: bsegall@google.com, pjt@google.com, morten.rasmussen@arm.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, juri.lelli@arm.com, Yuyang Du Subject: [PATCH 3/4] sched/fair: Modify accumulated sums for load/util averages Date: Mon, 11 Apr 2016 06:36:04 +0800 Message-Id: <1460327765-18024-4-git-send-email-yuyang.du@intel.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1460327765-18024-1-git-send-email-yuyang.du@intel.com> References: <1460327765-18024-1-git-send-email-yuyang.du@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2721 Lines: 92 After we dropped the incomplete period, the current period should be a complete "past" period, since all period boundaries, in the past or in the future, are predetermined. With incomplete current period: | | | | | -------------------* ^ ^ | | current With this patch: | | | | | -------------------* ^ ^ | | current So, the precomputed sums in __accumulated_sum_N[] and __accumulated_sum_N32[] should be updated accordingly. Update the script to generate the constants: print " #: inv_N sum_N" print "-----------------------" y = (0.5)**(1/32.0) x = 2**32 xx = 1024 for i in range(0, 32): if i == 0: x = x-1 else: x = x*y xx = int(xx*y + 1024) print "%2d: %#x %8d" % (i, int(x), int(xx)) print " #: sum_N32" print "------------" xxx = xx for i in range(0, 11): if i == 0: xxx = xx else: xxx = xxx/2 + xx print "%2d: %8d" % (i, xxx) Signed-off-by: Yuyang Du --- kernel/sched/fair.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 68273e8..49e9f1a 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -666,7 +666,7 @@ static unsigned long task_h_load(struct task_struct *p); */ #define LOAD_AVG_PERIOD 32 #define LOAD_AVG_MAX 47742 /* maximum possible load avg */ -#define LOAD_AVG_MAX_N 345 /* number of full periods to produce LOAD_AVG_MAX */ +#define LOAD_AVG_MAX_N 347 /* number of full periods to produce LOAD_AVG_MAX */ /* Give new sched_entity start runnable values to heavy its load in infant time */ void init_entity_runnable_average(struct sched_entity *se) @@ -2591,9 +2591,9 @@ static const u32 __decay_inv_multiply_N[] = { * over-estimates when re-combining. */ static const u32 __accumulated_sum_N[] = { - 0, 1002, 1982, 2941, 3880, 4798, 5697, 6576, 7437, 8279, 9103, - 9909,10698,11470,12226,12966,13690,14398,15091,15769,16433,17082, - 17718,18340,18949,19545,20128,20698,21256,21802,22336,22859,23371, + 0, 1024, 2026, 3006, 3965, 4904, 5822, 6721, 7600, 8461, 9303, + 10127,10933,11722,12494,13250,13990,14714,15422,16115,16793,17457, + 18106,18742,19364,19973,20569,21152,21722,22280,22826,23360,23883, }; /* @@ -2601,8 +2601,8 @@ static const u32 __accumulated_sum_N[] = { * lower integers. */ static const u32 __accumulated_sum_N32[] = { - 0, 23371, 35056, 40899, 43820, 45281, - 46011, 46376, 46559, 46650, 46696, 46719, + 0, 23883, 35824, 41795, 44780, 46273, + 47019, 47392, 47579, 47672, 47719, 47742, }; /* -- 2.1.4