On Wed, 25 Jun 2014 14:40:12 +0300
"Michael S. Tsirkin" <m...@redhat.com> wrote:
> It is necessary to reset RTC interrupt reinjection backlog if
> guest time is synchronized via a different mechanism, such as
> QGA's guest-set-time command.
>
> Failing to do so causes both corrections to be applied (summed),
> resulting in an incorrect guest time.
>
> Signed-off-by: Marcelo Tosatti <mtosa...@redhat.com>
> Reviewed-by: Michael S. Tsirkin <m...@redhat.com>
> Signed-off-by: Michael S. Tsirkin <m...@redhat.com>
Should this go via qmp tree or are you going to apply it to your tree?
> ---
>
> Marcelo, is this right?
>
> Changes from v3:
> rebase on top of master
> fixes error code
> drop dead code
>
> qapi-schema.json | 12 ++++++++++++
> hw/timer/mc146818rtc.c | 18 ++++++++++++++++++
> monitor.c | 7 +++++++
> qmp-commands.hx | 23 +++++++++++++++++++++++
> 4 files changed, 60 insertions(+)
>
> diff --git a/qapi-schema.json b/qapi-schema.json
> index f490403..a282805 100644
> --- a/qapi-schema.json
> +++ b/qapi-schema.json
> @@ -3288,3 +3288,15 @@
> # Since: 2.1
> ##
> { 'command': 'query-acpi-ospm-status', 'returns': ['ACPIOSTInfo'] }
> +
> +##
> +# @rtc-reset-reinjection
> +#
> +# This command will reset the RTC interrupt reinjection backlog.
> +# Can be used if another mechanism to synchronize guest time
> +# is in effect, for example QEMU guest agent's guest-set-time
> +# command.
> +#
> +# Since: 2.1
> +##
> +{ 'command': 'rtc-reset-reinjection' }
> diff --git a/hw/timer/mc146818rtc.c b/hw/timer/mc146818rtc.c
> index 1201f90..5bd8710 100644
> --- a/hw/timer/mc146818rtc.c
> +++ b/hw/timer/mc146818rtc.c
> @@ -26,6 +26,7 @@
> #include "sysemu/sysemu.h"
> #include "hw/timer/mc146818rtc.h"
> #include "qapi/visitor.h"
> +#include "qmp-commands.h"
>
> #ifdef TARGET_I386
> #include "hw/i386/apic.h"
> @@ -84,6 +85,7 @@ typedef struct RTCState {
> Notifier clock_reset_notifier;
> LostTickPolicy lost_tick_policy;
> Notifier suspend_notifier;
> + QLIST_ENTRY(RTCState) link;
> } RTCState;
>
> static void rtc_set_time(RTCState *s);
> @@ -522,6 +524,20 @@ static void rtc_get_time(RTCState *s, struct tm *tm)
> rtc_from_bcd(s, s->cmos_data[RTC_CENTURY]) * 100 - 1900;
> }
>
> +static QLIST_HEAD(, RTCState) rtc_devices =
> + QLIST_HEAD_INITIALIZER(rtc_devices);
> +
> +#ifdef TARGET_I386
> +void qmp_rtc_reset_reinjection(Error **errp)
> +{
> + RTCState *s;
> +
> + QLIST_FOREACH(s, &rtc_devices, link) {
> + s->irq_coalesced = 0;
> + }
> +}
> +#endif
> +
> static void rtc_set_time(RTCState *s)
> {
> struct tm tm;
> @@ -910,6 +926,8 @@ ISADevice *rtc_init(ISABus *bus, int base_year, qemu_irq
> intercept_irq)
> } else {
> isa_init_irq(isadev, &s->irq, RTC_ISA_IRQ);
> }
> + QLIST_INSERT_HEAD(&rtc_devices, s, link);
> +
> return isadev;
> }
>
> diff --git a/monitor.c b/monitor.c
> index 8c17f89..f7a0206 100644
> --- a/monitor.c
> +++ b/monitor.c
> @@ -5483,3 +5483,10 @@ QemuOptsList qemu_mon_opts = {
> { /* end of list */ }
> },
> };
> +
> +#ifndef TARGET_I386
> +void qmp_rtc_reset_reinjection(Error **errp)
> +{
> + error_set(errp, QERR_FEATURE_DISABLED, "rtc-reset-reinjection");
> +}
> +#endif
> diff --git a/qmp-commands.hx b/qmp-commands.hx
> index e4a1c80..17c09de 100644
> --- a/qmp-commands.hx
> +++ b/qmp-commands.hx
> @@ -3661,3 +3661,26 @@ Example:
> { "slot": "3", "slot-type": "DIMM", "source": 0, "status":
> 0}
> ]}
> EQMP
> +
> +#if defined TARGET_I386
> + {
> + .name = "rtc-reset-reinjection",
> + .args_type = "",
> + .mhandler.cmd_new = qmp_marshal_input_rtc_reset_reinjection,
> + },
> +#endif
> +
> +SQMP
> +rtc-reset-reinjection
> +---------------------
> +
> +Reset the RTC interrupt reinjection backlog.
> +
> +Arguments: None.
> +
> +Example:
> +
> +-> { "execute": "rtc-reset-reinjection" }
> +<- { "return": {} }
> +
> +EQMP
