clock.c File Reference

Implementations of functions in clock.h. More...

#include "clock.h"
#include "low_level_platform.h"

Functions
void	clock_sync_add_offset (instant_t *t)
	Add the current clock synchronization offset to a specified timestamp.
void	clock_sync_subtract_offset (instant_t *t)
	Subtract the clock synchronization offset from a timestamp.
int	lf_clock_gettime (instant_t *now)
int	lf_clock_interruptable_sleep_until_locked (environment_t *env, instant_t wakeup_time)
int	lf_clock_cond_timedwait (lf_cond_t *cond, instant_t wakeup_time)

Detailed Description

Implementations of functions in clock.h.

Author

Erling Jellum

Copyright

(c) 2020-2024, The University of California at Berkeley. License: BSD 2-clause

Function Documentation

clock_sync_add_offset()

void clock_sync_add_offset

(

instant_t *

t

)

Add the current clock synchronization offset to a specified timestamp.

Parameters

t	Pointer to the timestamp to which to add the offset.

clock_sync_subtract_offset()

void clock_sync_subtract_offset

(

instant_t *

t

)

Subtract the clock synchronization offset from a timestamp.

Parameters

t	The timestamp from which to subtract the current clock sync offset.

lf_clock_cond_timedwait()

int lf_clock_cond_timedwait	(	lf_cond_t *	cond,
		instant_t	wakeup_time )

Block the calling thread on the condition variable until it is signaled or until wakeup_time is reached. Before calling the appropriate function in the platform API, the wakeup_time will be translated into the correct timescale by removing any clock synchronization offset.

Returns

0 on success, LF_TIMEOUT on timeout, platform-specific error otherwise.

lf_clock_gettime()

int lf_clock_gettime

(

instant_t *

now

)

Retrieve the current physical time from the platform API. This adds any clock synchronization offset and guarantees monotonicity. Specifically, each returned value will be at least one nanosecond larger than any previously returned time.

Parameters

now	A pointer to the location in which to store the result.

Returns

0 on success, -1 on failure to read the platform clock.

lf_clock_interruptable_sleep_until_locked()

int lf_clock_interruptable_sleep_until_locked	(	environment_t *	env,
		instant_t	wakeup_time )

Block the calling thread until wakeup_time is reached or the thread is interrupted by an asynchronous scheduling. This is used by the single-threaded runtime. Before calling the appropriate function in the platform API, the wakeup_time will be translated into the correct timescale by removing any clock synchronization offset.

Returns

0 on success or -1 if interrupted.