2 * Copyright (c) 2012 Konstantin Belousov <kib@FreeBSD.org>
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
34 #include <machine/atomic.h>
35 #include "libc_private.h"
38 tc_delta(const struct vdso_timehands *th)
41 return ((__vdso_gettc(th) - th->th_offset_count) &
46 binuptime(struct bintime *bt, struct vdso_timekeep *tk, int abs)
48 struct vdso_timehands *th;
56 * XXXKIB. The load of tk->tk_current should use
57 * atomic_load_acq_32 to provide load barrier. But
58 * since tk points to r/o mapped page, x86
59 * implementation of atomic_load_acq faults.
61 curr = tk->tk_current;
63 th = &tk->tk_th[curr];
64 if (th->th_algo != VDSO_TH_ALGO_1)
68 bintime_addx(bt, th->th_scale * tc_delta(th));
70 bintime_add(bt, &th->th_boottime);
73 * Barrier for load of both tk->tk_current and th->th_gen.
76 } while (curr != tk->tk_current || gen == 0 || gen != th->th_gen);
80 static struct vdso_timekeep *tk;
82 #pragma weak __vdso_gettimeofday
84 __vdso_gettimeofday(struct timeval *tv, struct timezone *tz)
92 error = __vdso_gettimekeep(&tk);
93 if (error != 0 || tk == NULL)
96 if (tk->tk_ver != VDSO_TK_VER_CURR)
98 error = binuptime(&bt, tk, 1);
101 bintime2timeval(&bt, tv);
105 #pragma weak __vdso_clock_gettime
107 __vdso_clock_gettime(clockid_t clock_id, struct timespec *ts)
113 error = _elf_aux_info(AT_TIMEKEEP, &tk, sizeof(tk));
114 if (error != 0 || tk == NULL)
117 if (tk->tk_ver != VDSO_TK_VER_CURR)
121 case CLOCK_REALTIME_PRECISE:
122 case CLOCK_REALTIME_FAST:
126 case CLOCK_MONOTONIC:
127 case CLOCK_MONOTONIC_PRECISE:
128 case CLOCK_MONOTONIC_FAST:
130 case CLOCK_UPTIME_PRECISE:
131 case CLOCK_UPTIME_FAST:
137 error = binuptime(&bt, tk, abs);
140 bintime2timespec(&bt, ts);
141 if (clock_id == CLOCK_SECOND)