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// SPDX-License-Identifier: GPL-2.0 //! Time related primitives.//!//! This module contains the kernel APIs related to time and timers that//! have been ported or wrapped for usage by Rust code in the kernel.//!//! C header: [`include/linux/jiffies.h`](srctree/include/linux/jiffies.h).//! C header: [`include/linux/ktime.h`](srctree/include/linux/ktime.h). /// The number of nanoseconds per millisecond.pub const NSEC_PER_MSEC: i64 = bindings::NSEC_PER_MSEC as i64; /// The time unit of Linux kernel. One jiffy equals (1/HZ) second.pub type Jiffies = crate::ffi::c_ulong; /// The millisecond time unit.pub type Msecs = crate::ffi::c_uint; /// Converts milliseconds to jiffies.#[inline]pub fn msecs_to_jiffies(msecs: Msecs) -> Jiffies {    // SAFETY: The `__msecs_to_jiffies` function is always safe to call no    // matter what the argument is.    unsafe { bindings::__msecs_to_jiffies(msecs) }} /// A Rust wrapper around a `ktime_t`.#[repr(transparent)]#[derive(Copy, Clone)]pub struct Ktime {    inner: bindings::ktime_t,} impl Ktime {    /// Create a `Ktime` from a raw `ktime_t`.    #[inline]    pub fn from_raw(inner: bindings::ktime_t) -> Self {        Self { inner }    }     /// Get the current time using `CLOCK_MONOTONIC`.    #[inline]    pub fn ktime_get() -> Self {        // SAFETY: It is always safe to call `ktime_get` outside of NMI context.        Self::from_raw(unsafe { bindings::ktime_get() })    }     /// Divide the number of nanoseconds by a compile-time constant.    #[inline]    fn divns_constant<const DIV: i64>(self) -> i64 {        self.to_ns() / DIV    }     /// Returns the number of nanoseconds.    #[inline]    pub fn to_ns(self) -> i64 {        self.inner    }     /// Returns the number of milliseconds.    #[inline]    pub fn to_ms(self) -> i64 {        self.divns_constant::<NSEC_PER_MSEC>()    }} /// Returns the number of milliseconds between two ktimes.#[inline]pub fn ktime_ms_delta(later: Ktime, earlier: Ktime) -> i64 {    (later - earlier).to_ms()} impl core::ops::Sub for Ktime {    type Output = Ktime;     #[inline]    fn sub(self, other: Ktime) -> Ktime {        Self {            inner: self.inner - other.inner,        }    }}