Files
scylladb/utils/coarse_steady_clock.hh
Avi Kivity fcb8d040e8 treewide: use Software Package Data Exchange (SPDX) license identifiers
Instead of lengthy blurbs, switch to single-line, machine-readable
standardized (https://spdx.dev) license identifiers. The Linux kernel
switched long ago, so there is strong precedent.

Three cases are handled: AGPL-only, Apache-only, and dual licensed.
For the latter case, I chose (AGPL-3.0-or-later and Apache-2.0),
reasoning that our changes are extensive enough to apply our license.

The changes we applied mechanically with a script, except to
licenses/README.md.

Closes #9937
2022-01-18 12:15:18 +01:00

38 lines
908 B
C++

/*
* Copyright (C) 2021-present ScyllaDB
*/
/*
* SPDX-License-Identifier: AGPL-3.0-or-later
*/
#pragma once
// A coarser and faster version of std::steady_clock, using
// CLOCK_MONOTONIC_COARSE instead of CLOCK_MONOTONIC.
//
// Intended for measuring time taken by synchronous code paths (where
// seastar::lowres_clock is not suitable).
#include <chrono>
#include <ctime>
namespace utils {
struct coarse_steady_clock {
using duration = std::chrono::nanoseconds;
using rep = duration::rep;
using period = duration::period;
using time_point = std::chrono::time_point<coarse_steady_clock, duration>;
static constexpr bool is_steady = true;
static time_point now() noexcept {
timespec tp;
clock_gettime(CLOCK_MONOTONIC_COARSE, &tp);
return time_point(std::chrono::seconds(tp.tv_sec) + std::chrono::nanoseconds(tp.tv_nsec));
};
};
};