/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved.
*/
#include "lint.h"
#include "thr_uberdata.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <atomic.h>
#include <sys/clock.h>
#include <sys/time.h>
#include <sys/hrt.h>
extern void *gethrt(void);
/*
* Pointer to data to compute hrtime from TSCP.
*/
volatile hrt_t *hrt = NULL;
/*
* Get a pointer to high resolution time data via gethrt() fast trap.
* This is called the first time a process calls either gethrtime(3C) or
* gettimeofday(3C).
*/
volatile hrt_t *
map_hrt(void)
{
hrt_t *new;
new = (hrt_t *)gethrt();
if (new == NULL)
return (NULL);
/*
* hrt must be atomically updated to prevent another thread from
* reading a partial update.
*/
atomic_swap_ptr((volatile void *)&hrt, (void *)new);
return (hrt);
}