mpd/src/thread/Slack.hxx
2023-03-06 14:59:48 +01:00

38 lines
885 B
C++

// SPDX-License-Identifier: GPL-2.0-or-later
// Copyright The Music Player Daemon Project
#ifndef MPD_THREAD_SLACK_HXX
#define MPD_THREAD_SLACK_HXX
#include "config.h"
#include <chrono>
#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
}
template<class Rep, class Period>
static inline auto
SetThreadTimerSlack(const std::chrono::duration<Rep,Period> &slack) noexcept
{
SetThreadTimerSlackNS(std::chrono::duration_cast<std::chrono::nanoseconds>(slack).count());
}
#endif