/*************************************************************************** * Copyright (C) 2008 by Sindre AamÄs * * aamas@stud.ntnu.no * * * * This program is free software; you can redistribute it and/or modify * * it under the terms of the GNU General Public License version 2 as * * published by the Free Software Foundation. * * * * This program is distributed in the hope that it will be useful, * * but WITHOUT ANY WARRANTY; without even the implied warranty of * * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * * GNU General Public License version 2 for more details. * * * * You should have received a copy of the GNU General Public License * * version 2 along with this program; if not, write to the * * Free Software Foundation, Inc., * * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * ***************************************************************************/ #include "adaptivesleep.h" usec_t AdaptiveSleep::sleepUntil(usec_t base, usec_t inc) { usec_t now = getusecs(); usec_t diff = now - base; if (diff >= inc) return diff - inc; diff = inc - diff; if (diff > oversleep + oversleepVar) { diff -= oversleep + oversleepVar; usecsleep(diff); const usec_t ideal = now + diff; now = getusecs(); { usec_t curOversleep = now - ideal; if (negate(curOversleep) < curOversleep) curOversleep = 0; oversleepVar = (oversleepVar * 15 + (curOversleep < oversleep ? oversleep - curOversleep : curOversleep - oversleep) + 8) >> 4; oversleep = (oversleep * 15 + curOversleep + 8) >> 4; } noSleep = 60; } else if (--noSleep == 0) { noSleep = 60; oversleep = oversleepVar = 0; } while (now - base < inc) now = getusecs(); return 0; }