diff options
Diffstat (limited to 'sys/i386/xen/xen_clock_util.c')
| -rw-r--r-- | sys/i386/xen/xen_clock_util.c | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/sys/i386/xen/xen_clock_util.c b/sys/i386/xen/xen_clock_util.c new file mode 100644 index 0000000..c14a627 --- /dev/null +++ b/sys/i386/xen/xen_clock_util.c @@ -0,0 +1,101 @@ +/*- + * Copyright (c) 2009 Adrian Chadd + * All rights reserved. + * + * 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. + * + * $FreeBSD$ + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/bus.h> +#include <sys/clock.h> +#include <sys/lock.h> +#include <sys/mutex.h> +#include <sys/kernel.h> +#include <sys/module.h> +#include <sys/time.h> + +#include <xen/xen_intr.h> +#include <vm/vm.h> +#include <vm/pmap.h> +#include <machine/pmap.h> +#include <xen/hypervisor.h> +#include <machine/xen/xen-os.h> +#include <machine/xen/xenfunc.h> +#include <xen/interface/io/xenbus.h> +#include <xen/interface/vcpu.h> +#include <machine/cpu.h> + +#include <machine/xen/xen_clock_util.h> + +/* + * Read the current hypervisor start time (wall clock) from Xen. + */ +void +xen_fetch_wallclock(struct timespec *ts) +{ + shared_info_t *s = HYPERVISOR_shared_info; + uint32_t ts_version; + + do { + ts_version = s->wc_version; + rmb(); + ts->tv_sec = s->wc_sec; + ts->tv_nsec = s->wc_nsec; + rmb(); + } + while ((s->wc_version & 1) | (ts_version ^ s->wc_version)); +} + +/* + * Read the current hypervisor system uptime value from Xen. + */ +void +xen_fetch_uptime(struct timespec *ts) +{ + shared_info_t *s = HYPERVISOR_shared_info; + struct vcpu_time_info *src; + struct shadow_time_info dst; + uint32_t pre_version, post_version; + + src = &s->vcpu_info[smp_processor_id()].time; + + spinlock_enter(); + do { + pre_version = dst.version = src->version; + rmb(); + dst.system_timestamp = src->system_time; + rmb(); + post_version = src->version; + } + while ((pre_version & 1) | (pre_version ^ post_version)); + + spinlock_exit(); + + ts->tv_sec = dst.system_timestamp / 1000000000; + ts->tv_nsec = dst.system_timestamp % 1000000000; +} |
