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/*
* Copyright 2003-2018 The Music Player Daemon Project
* http://www.musicpd.org
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* 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 for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef MPD_THREAD_SLACK_HXX
#define MPD_THREAD_SLACK_HXX
#include "config.h"
#ifdef HAVE_PRCTL
#include <sys/prctl.h>
#endif
/**
* Set the current thread's timer slack to the specified number of
* nanoseconds (requires Linux 2.6.28). This allows the kernel to
* merge multiple wakeups, which is a trick to save energy.
*/
static inline void
SetThreadTimerSlackNS(unsigned long slack_ns) noexcept
{
#if defined(HAVE_PRCTL) && defined(PR_SET_TIMERSLACK)
prctl(PR_SET_TIMERSLACK, slack_ns, 0, 0, 0);
#else
(void)slack_ns;
#endif
}
static inline void
SetThreadTimerSlackUS(unsigned long slack_us) noexcept
{
SetThreadTimerSlackNS(slack_us * 1000ul);
}
static inline void
SetThreadTimerSlackMS(unsigned long slack_ms) noexcept
{
SetThreadTimerSlackNS(slack_ms * 1000000ul);
}
#endif