diff --git a/lib/libc/sys/__vdso_gettimeofday.c b/lib/libc/sys/__vdso_gettimeofday.c index c1457a54d37e..cf1400cdf291 100644 --- a/lib/libc/sys/__vdso_gettimeofday.c +++ b/lib/libc/sys/__vdso_gettimeofday.c @@ -1,199 +1,199 @@ /*- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * * Copyright (c) 2012 Konstantin Belousov * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include "libc_private.h" static int tc_delta(const struct vdso_timehands *th, u_int *delta) { int error; u_int tc; error = __vdso_gettc(th, &tc); if (error == 0) *delta = (tc - th->th_offset_count) & th->th_counter_mask; return (error); } /* * Calculate the absolute or boot-relative time from the * machine-specific fast timecounter and the published timehands * structure read from the shared page. * * The lockless reading scheme is similar to the one used to read the * in-kernel timehands, see sys/kern/kern_tc.c:binuptime(). This code * is based on the kernel implementation. */ static int binuptime(struct bintime *bt, struct vdso_timekeep *tk, bool abs) { struct vdso_timehands *th; uint32_t curr, gen; uint64_t scale, x; u_int delta, scale_bits; int error; do { if (!tk->tk_enabled) return (ENOSYS); curr = atomic_load_acq_32(&tk->tk_current); th = &tk->tk_th[curr]; gen = atomic_load_acq_32(&th->th_gen); *bt = th->th_offset; error = tc_delta(th, &delta); if (error == EAGAIN) continue; if (error != 0) return (error); scale = th->th_scale; #ifdef _LP64 - scale_bits = ffsl(scale); + scale_bits = flsl(scale); #else - scale_bits = ffsll(scale); + scale_bits = flsll(scale); #endif if (__predict_false(scale_bits + fls(delta) > 63)) { x = (scale >> 32) * delta; scale &= 0xffffffff; bt->sec += x >> 32; bintime_addx(bt, x << 32); } bintime_addx(bt, scale * delta); if (abs) bintime_add(bt, &th->th_boottime); /* * Ensure that the load of th_offset is completed * before the load of th_gen. */ atomic_thread_fence_acq(); } while (curr != tk->tk_current || gen == 0 || gen != th->th_gen); return (0); } static int getnanouptime(struct bintime *bt, struct vdso_timekeep *tk) { struct vdso_timehands *th; uint32_t curr, gen; do { if (!tk->tk_enabled) return (ENOSYS); curr = atomic_load_acq_32(&tk->tk_current); th = &tk->tk_th[curr]; gen = atomic_load_acq_32(&th->th_gen); *bt = th->th_offset; /* * Ensure that the load of th_offset is completed * before the load of th_gen. */ atomic_thread_fence_acq(); } while (curr != tk->tk_current || gen == 0 || gen != th->th_gen); return (0); } static struct vdso_timekeep *tk; #pragma weak __vdso_gettimeofday int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz) { struct bintime bt; int error; if (tz != NULL) return (ENOSYS); if (tk == NULL) { error = __vdso_gettimekeep(&tk); if (error != 0 || tk == NULL) return (ENOSYS); } if (tk->tk_ver != VDSO_TK_VER_CURR) return (ENOSYS); error = binuptime(&bt, tk, true); if (error != 0) return (error); bintime2timeval(&bt, tv); return (0); } #pragma weak __vdso_clock_gettime int __vdso_clock_gettime(clockid_t clock_id, struct timespec *ts) { struct bintime bt; int error; if (tk == NULL) { error = _elf_aux_info(AT_TIMEKEEP, &tk, sizeof(tk)); if (error != 0 || tk == NULL) return (ENOSYS); } if (tk->tk_ver != VDSO_TK_VER_CURR) return (ENOSYS); switch (clock_id) { case CLOCK_REALTIME: case CLOCK_REALTIME_PRECISE: case CLOCK_REALTIME_FAST: case CLOCK_SECOND: error = binuptime(&bt, tk, true); break; case CLOCK_MONOTONIC: case CLOCK_MONOTONIC_PRECISE: case CLOCK_UPTIME: case CLOCK_UPTIME_PRECISE: error = binuptime(&bt, tk, false); break; case CLOCK_MONOTONIC_FAST: case CLOCK_UPTIME_FAST: error = getnanouptime(&bt, tk); break; default: error = ENOSYS; break; } if (error != 0) return (error); bintime2timespec(&bt, ts); if (clock_id == CLOCK_SECOND) ts->tv_nsec = 0; return (0); }