Message ID | 20180918185246.18109-2-danielhb413@gmail.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | wakeup-from-suspend and system_wakeup changes | expand |
Daniel Henrique Barboza <danielhb413@gmail.com> writes: > When issuing the qmp/hmp 'system_wakeup' command, what happens in a > nutshell is: > > - qmp_system_wakeup_request set runstate to RUNNING, sets a wakeup_reason > and notify the event > - in the main_loop, all vcpus are paused, a system reset is issued, all > subscribers of wakeup_notifiers receives a notification, vcpus are then > resumed and the wake up QAPI event is fired > > Note that this procedure alone doesn't ensure that the guest will awake > from SUSPENDED state - the subscribers of the wake up event must take > action to resume the guest, otherwise the guest will simply reboot. At > this moment, only the ACPI machines via acpi_pm1_cnt_init has wake-up > from suspend support. > > However, only the presence of 'system_wakeup' is required for QGA to > support 'guest-suspend-ram' and 'guest-suspend-hybrid' at this moment. > This means that the user/management will expect to suspend the guest using > one of those suspend commands and then resume execution using system_wakeup, > regardless of the support offered in system_wakeup in the first place. > > This patch creates a new API called query-current-machine [1], that holds > a new flag called 'wakeup-suspend-support' that indicates if the guest > supports wake up from suspend via system_wakeup. The machine is considered > to implement wake-up support if a call to a new 'qemu_register_wakeup_support' > is made during its init, as it is now being done inside acpi_pm1_cnt_init. > This allows for any other machine type to declare wake-up support regardless > of ACPI state or wakeup_notifiers subscription, making easier for > newer implementations that might have its own mechanisms in the future. > > This is the expected output of query-current-machine when running a x86 > guest: > > {"execute" : "query-current-machine"} > {"return": {"wakeup-suspend-support": true}} > > Running the same x86 guest, but with the --no-acpi option: > > {"execute" : "query-current-machine"} > {"return": {"wakeup-suspend-support": false}} > > This is the output when running a pseries guest: > > {"execute" : "query-current-machine"} > {"return": {"wakeup-suspend-support": false}} > > With this extra tool, management can avoid situations where a guest > that does not have proper suspend/wake capabilities ends up in > inconsistent state (e.g. > https://github.com/open-power-host-os/qemu/issues/31). > > [1] the decision of creating the query-current-machine API is based > on discussions in the QEMU mailing list where it was decided that > query-target wasn't a proper place to store the wake-up flag, neither > was query-machines because this isn't a static property of the > machine object. This new API can then be used to store other > dynamic machine properties that are scattered around the code > ATM. More info at: > https://lists.gnu.org/archive/html/qemu-devel/2018-05/msg04235.html > > Reported-by: Balamuruhan S <bala24@linux.vnet.ibm.com> > Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com> > --- > hw/acpi/core.c | 1 + > include/sysemu/sysemu.h | 1 + > qapi/misc.json | 24 ++++++++++++++++++++++++ > vl.c | 19 +++++++++++++++++++ > 4 files changed, 45 insertions(+) > > diff --git a/hw/acpi/core.c b/hw/acpi/core.c > index b8d39012cd..2dea893245 100644 > --- a/hw/acpi/core.c > +++ b/hw/acpi/core.c > @@ -617,6 +617,7 @@ void acpi_pm1_cnt_init(ACPIREGS *ar, MemoryRegion *parent, > ar->pm1.cnt.s4_val = s4_val; > ar->wakeup.notify = acpi_notify_wakeup; > qemu_register_wakeup_notifier(&ar->wakeup); > + qemu_register_wakeup_support(); > memory_region_init_io(&ar->pm1.cnt.io, memory_region_owner(parent), > &acpi_pm_cnt_ops, ar, "acpi-cnt", 2); > memory_region_add_subregion(parent, 4, &ar->pm1.cnt.io); We might've discussed this before, not sure... There's a second qemu_register_wakeup_notifier() in xen-hvm.c. By not adding qemu_register_wakeup_support() there, you implicitly state that it doesn't provide wakeup support. I have no idea whether that's true. If it is, then I think the commit message should explain it. We might even want a comment. Please advise. > diff --git a/include/sysemu/sysemu.h b/include/sysemu/sysemu.h > index 8d6095d98b..0446adacc6 100644 > --- a/include/sysemu/sysemu.h > +++ b/include/sysemu/sysemu.h > @@ -77,6 +77,7 @@ void qemu_register_suspend_notifier(Notifier *notifier); > void qemu_system_wakeup_request(WakeupReason reason); > void qemu_system_wakeup_enable(WakeupReason reason, bool enabled); > void qemu_register_wakeup_notifier(Notifier *notifier); > +void qemu_register_wakeup_support(void); > void qemu_system_shutdown_request(ShutdownCause reason); > void qemu_system_powerdown_request(void); > void qemu_register_powerdown_notifier(Notifier *notifier); > diff --git a/qapi/misc.json b/qapi/misc.json > index d450cfef21..b616d385a4 100644 > --- a/qapi/misc.json > +++ b/qapi/misc.json > @@ -2003,6 +2003,30 @@ > ## > { 'command': 'query-machines', 'returns': ['MachineInfo'] } > > +## > +# @CurrentMachineParams: > +# > +# Information describing the running machine parameters. > +# > +# @wakeup-suspend-support: true if the target supports wake up from s/target/machine/ > +# suspend > +# > +# Since: 3.1.0 > +## > +{ 'struct': 'CurrentMachineParams', > + 'data': { 'wakeup-suspend-support': 'bool'} } > + > +## > +# @query-current-machine: > +# > +# Return a list of parameters of the running machine. "a list of" suggests it returns a QAPI list. Let's say "Return information on the current virtual machine". > +# > +# Returns: CurrentMachineParams > +# > +# Since: 3.1.0 > +## > +{ 'command': 'query-current-machine', 'returns': 'CurrentMachineParams' } > + > ## > # @CpuDefinitionInfo: > # > diff --git a/vl.c b/vl.c > index 5ba06adf78..f78947f69c 100644 > --- a/vl.c > +++ b/vl.c > @@ -184,6 +184,7 @@ bool boot_strict; > uint8_t *boot_splash_filedata; > size_t boot_splash_filedata_size; > uint8_t qemu_extra_params_fw[2]; > +bool wakeup_suspend_enabled; > > int icount_align_option; > > @@ -1753,6 +1754,24 @@ void qemu_register_wakeup_notifier(Notifier *notifier) > notifier_list_add(&wakeup_notifiers, notifier); > } > > +void qemu_register_wakeup_support(void) > +{ > + wakeup_suspend_enabled = true; > +} > + > +static bool qemu_wakeup_suspend_enabled(void) > +{ > + return wakeup_suspend_enabled; > +} > + > +CurrentMachineParams *qmp_query_current_machine(Error **errp) > +{ > + CurrentMachineParams *params = g_malloc0(sizeof(*params)); > + params->wakeup_suspend_support = qemu_wakeup_suspend_enabled(); > + > + return params; > +} > + > void qemu_system_killed(int signal, pid_t pid) > { > shutdown_signal = signal;
On 10/11/18 4:38 AM, Markus Armbruster wrote: > Daniel Henrique Barboza <danielhb413@gmail.com> writes: > >> When issuing the qmp/hmp 'system_wakeup' command, what happens in a >> nutshell is: >> >> - qmp_system_wakeup_request set runstate to RUNNING, sets a wakeup_reason >> and notify the event >> - in the main_loop, all vcpus are paused, a system reset is issued, all >> subscribers of wakeup_notifiers receives a notification, vcpus are then >> resumed and the wake up QAPI event is fired >> >> Note that this procedure alone doesn't ensure that the guest will awake >> from SUSPENDED state - the subscribers of the wake up event must take >> action to resume the guest, otherwise the guest will simply reboot. At >> this moment, only the ACPI machines via acpi_pm1_cnt_init has wake-up >> from suspend support. >> >> However, only the presence of 'system_wakeup' is required for QGA to >> support 'guest-suspend-ram' and 'guest-suspend-hybrid' at this moment. >> This means that the user/management will expect to suspend the guest using >> one of those suspend commands and then resume execution using system_wakeup, >> regardless of the support offered in system_wakeup in the first place. >> >> This patch creates a new API called query-current-machine [1], that holds >> a new flag called 'wakeup-suspend-support' that indicates if the guest >> supports wake up from suspend via system_wakeup. The machine is considered >> to implement wake-up support if a call to a new 'qemu_register_wakeup_support' >> is made during its init, as it is now being done inside acpi_pm1_cnt_init. >> This allows for any other machine type to declare wake-up support regardless >> of ACPI state or wakeup_notifiers subscription, making easier for >> newer implementations that might have its own mechanisms in the future. >> >> This is the expected output of query-current-machine when running a x86 >> guest: >> >> {"execute" : "query-current-machine"} >> {"return": {"wakeup-suspend-support": true}} >> >> Running the same x86 guest, but with the --no-acpi option: >> >> {"execute" : "query-current-machine"} >> {"return": {"wakeup-suspend-support": false}} >> >> This is the output when running a pseries guest: >> >> {"execute" : "query-current-machine"} >> {"return": {"wakeup-suspend-support": false}} >> >> With this extra tool, management can avoid situations where a guest >> that does not have proper suspend/wake capabilities ends up in >> inconsistent state (e.g. >> https://github.com/open-power-host-os/qemu/issues/31). >> >> [1] the decision of creating the query-current-machine API is based >> on discussions in the QEMU mailing list where it was decided that >> query-target wasn't a proper place to store the wake-up flag, neither >> was query-machines because this isn't a static property of the >> machine object. This new API can then be used to store other >> dynamic machine properties that are scattered around the code >> ATM. More info at: >> https://lists.gnu.org/archive/html/qemu-devel/2018-05/msg04235.html >> >> Reported-by: Balamuruhan S <bala24@linux.vnet.ibm.com> >> Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com> >> --- >> hw/acpi/core.c | 1 + >> include/sysemu/sysemu.h | 1 + >> qapi/misc.json | 24 ++++++++++++++++++++++++ >> vl.c | 19 +++++++++++++++++++ >> 4 files changed, 45 insertions(+) >> >> diff --git a/hw/acpi/core.c b/hw/acpi/core.c >> index b8d39012cd..2dea893245 100644 >> --- a/hw/acpi/core.c >> +++ b/hw/acpi/core.c >> @@ -617,6 +617,7 @@ void acpi_pm1_cnt_init(ACPIREGS *ar, MemoryRegion *parent, >> ar->pm1.cnt.s4_val = s4_val; >> ar->wakeup.notify = acpi_notify_wakeup; >> qemu_register_wakeup_notifier(&ar->wakeup); >> + qemu_register_wakeup_support(); >> memory_region_init_io(&ar->pm1.cnt.io, memory_region_owner(parent), >> &acpi_pm_cnt_ops, ar, "acpi-cnt", 2); >> memory_region_add_subregion(parent, 4, &ar->pm1.cnt.io); > We might've discussed this before, not sure... There's a second > qemu_register_wakeup_notifier() in xen-hvm.c. By not adding > qemu_register_wakeup_support() there, you implicitly state that it > doesn't provide wakeup support. I have no idea whether that's true. If > it is, then I think the commit message should explain it. We might even > want a comment. Please advise. Not adding the wakeup notifier at xen-hvm.c was a mistake. I am under the assumption that everyone that register a notifier is implementing wakeup support, which seems reasonable to me (why else would you want to listen to that event?). Simply put, I failed to check on all callers of qemu_register_wakeup_notifier(). Thanks for noticing it. > >> diff --git a/include/sysemu/sysemu.h b/include/sysemu/sysemu.h >> index 8d6095d98b..0446adacc6 100644 >> --- a/include/sysemu/sysemu.h >> +++ b/include/sysemu/sysemu.h >> @@ -77,6 +77,7 @@ void qemu_register_suspend_notifier(Notifier *notifier); >> void qemu_system_wakeup_request(WakeupReason reason); >> void qemu_system_wakeup_enable(WakeupReason reason, bool enabled); >> void qemu_register_wakeup_notifier(Notifier *notifier); >> +void qemu_register_wakeup_support(void); >> void qemu_system_shutdown_request(ShutdownCause reason); >> void qemu_system_powerdown_request(void); >> void qemu_register_powerdown_notifier(Notifier *notifier); >> diff --git a/qapi/misc.json b/qapi/misc.json >> index d450cfef21..b616d385a4 100644 >> --- a/qapi/misc.json >> +++ b/qapi/misc.json >> @@ -2003,6 +2003,30 @@ >> ## >> { 'command': 'query-machines', 'returns': ['MachineInfo'] } >> >> +## >> +# @CurrentMachineParams: >> +# >> +# Information describing the running machine parameters. >> +# >> +# @wakeup-suspend-support: true if the target supports wake up from > s/target/machine/ ok! > >> +# suspend >> +# >> +# Since: 3.1.0 >> +## >> +{ 'struct': 'CurrentMachineParams', >> + 'data': { 'wakeup-suspend-support': 'bool'} } >> + >> +## >> +# @query-current-machine: >> +# >> +# Return a list of parameters of the running machine. > "a list of" suggests it returns a QAPI list. Let's say "Return > information on the current virtual machine". ok! > >> +# >> +# Returns: CurrentMachineParams >> +# >> +# Since: 3.1.0 >> +## >> +{ 'command': 'query-current-machine', 'returns': 'CurrentMachineParams' } >> + >> ## >> # @CpuDefinitionInfo: >> # >> diff --git a/vl.c b/vl.c >> index 5ba06adf78..f78947f69c 100644 >> --- a/vl.c >> +++ b/vl.c >> @@ -184,6 +184,7 @@ bool boot_strict; >> uint8_t *boot_splash_filedata; >> size_t boot_splash_filedata_size; >> uint8_t qemu_extra_params_fw[2]; >> +bool wakeup_suspend_enabled; >> >> int icount_align_option; >> >> @@ -1753,6 +1754,24 @@ void qemu_register_wakeup_notifier(Notifier *notifier) >> notifier_list_add(&wakeup_notifiers, notifier); >> } >> >> +void qemu_register_wakeup_support(void) >> +{ >> + wakeup_suspend_enabled = true; >> +} >> + >> +static bool qemu_wakeup_suspend_enabled(void) >> +{ >> + return wakeup_suspend_enabled; >> +} >> + >> +CurrentMachineParams *qmp_query_current_machine(Error **errp) >> +{ >> + CurrentMachineParams *params = g_malloc0(sizeof(*params)); >> + params->wakeup_suspend_support = qemu_wakeup_suspend_enabled(); >> + >> + return params; >> +} >> + >> void qemu_system_killed(int signal, pid_t pid) >> { >> shutdown_signal = signal;
diff --git a/hw/acpi/core.c b/hw/acpi/core.c index b8d39012cd..2dea893245 100644 --- a/hw/acpi/core.c +++ b/hw/acpi/core.c @@ -617,6 +617,7 @@ void acpi_pm1_cnt_init(ACPIREGS *ar, MemoryRegion *parent, ar->pm1.cnt.s4_val = s4_val; ar->wakeup.notify = acpi_notify_wakeup; qemu_register_wakeup_notifier(&ar->wakeup); + qemu_register_wakeup_support(); memory_region_init_io(&ar->pm1.cnt.io, memory_region_owner(parent), &acpi_pm_cnt_ops, ar, "acpi-cnt", 2); memory_region_add_subregion(parent, 4, &ar->pm1.cnt.io); diff --git a/include/sysemu/sysemu.h b/include/sysemu/sysemu.h index 8d6095d98b..0446adacc6 100644 --- a/include/sysemu/sysemu.h +++ b/include/sysemu/sysemu.h @@ -77,6 +77,7 @@ void qemu_register_suspend_notifier(Notifier *notifier); void qemu_system_wakeup_request(WakeupReason reason); void qemu_system_wakeup_enable(WakeupReason reason, bool enabled); void qemu_register_wakeup_notifier(Notifier *notifier); +void qemu_register_wakeup_support(void); void qemu_system_shutdown_request(ShutdownCause reason); void qemu_system_powerdown_request(void); void qemu_register_powerdown_notifier(Notifier *notifier); diff --git a/qapi/misc.json b/qapi/misc.json index d450cfef21..b616d385a4 100644 --- a/qapi/misc.json +++ b/qapi/misc.json @@ -2003,6 +2003,30 @@ ## { 'command': 'query-machines', 'returns': ['MachineInfo'] } +## +# @CurrentMachineParams: +# +# Information describing the running machine parameters. +# +# @wakeup-suspend-support: true if the target supports wake up from +# suspend +# +# Since: 3.1.0 +## +{ 'struct': 'CurrentMachineParams', + 'data': { 'wakeup-suspend-support': 'bool'} } + +## +# @query-current-machine: +# +# Return a list of parameters of the running machine. +# +# Returns: CurrentMachineParams +# +# Since: 3.1.0 +## +{ 'command': 'query-current-machine', 'returns': 'CurrentMachineParams' } + ## # @CpuDefinitionInfo: # diff --git a/vl.c b/vl.c index 5ba06adf78..f78947f69c 100644 --- a/vl.c +++ b/vl.c @@ -184,6 +184,7 @@ bool boot_strict; uint8_t *boot_splash_filedata; size_t boot_splash_filedata_size; uint8_t qemu_extra_params_fw[2]; +bool wakeup_suspend_enabled; int icount_align_option; @@ -1753,6 +1754,24 @@ void qemu_register_wakeup_notifier(Notifier *notifier) notifier_list_add(&wakeup_notifiers, notifier); } +void qemu_register_wakeup_support(void) +{ + wakeup_suspend_enabled = true; +} + +static bool qemu_wakeup_suspend_enabled(void) +{ + return wakeup_suspend_enabled; +} + +CurrentMachineParams *qmp_query_current_machine(Error **errp) +{ + CurrentMachineParams *params = g_malloc0(sizeof(*params)); + params->wakeup_suspend_support = qemu_wakeup_suspend_enabled(); + + return params; +} + void qemu_system_killed(int signal, pid_t pid) { shutdown_signal = signal;
When issuing the qmp/hmp 'system_wakeup' command, what happens in a nutshell is: - qmp_system_wakeup_request set runstate to RUNNING, sets a wakeup_reason and notify the event - in the main_loop, all vcpus are paused, a system reset is issued, all subscribers of wakeup_notifiers receives a notification, vcpus are then resumed and the wake up QAPI event is fired Note that this procedure alone doesn't ensure that the guest will awake from SUSPENDED state - the subscribers of the wake up event must take action to resume the guest, otherwise the guest will simply reboot. At this moment, only the ACPI machines via acpi_pm1_cnt_init has wake-up from suspend support. However, only the presence of 'system_wakeup' is required for QGA to support 'guest-suspend-ram' and 'guest-suspend-hybrid' at this moment. This means that the user/management will expect to suspend the guest using one of those suspend commands and then resume execution using system_wakeup, regardless of the support offered in system_wakeup in the first place. This patch creates a new API called query-current-machine [1], that holds a new flag called 'wakeup-suspend-support' that indicates if the guest supports wake up from suspend via system_wakeup. The machine is considered to implement wake-up support if a call to a new 'qemu_register_wakeup_support' is made during its init, as it is now being done inside acpi_pm1_cnt_init. This allows for any other machine type to declare wake-up support regardless of ACPI state or wakeup_notifiers subscription, making easier for newer implementations that might have its own mechanisms in the future. This is the expected output of query-current-machine when running a x86 guest: {"execute" : "query-current-machine"} {"return": {"wakeup-suspend-support": true}} Running the same x86 guest, but with the --no-acpi option: {"execute" : "query-current-machine"} {"return": {"wakeup-suspend-support": false}} This is the output when running a pseries guest: {"execute" : "query-current-machine"} {"return": {"wakeup-suspend-support": false}} With this extra tool, management can avoid situations where a guest that does not have proper suspend/wake capabilities ends up in inconsistent state (e.g. https://github.com/open-power-host-os/qemu/issues/31). [1] the decision of creating the query-current-machine API is based on discussions in the QEMU mailing list where it was decided that query-target wasn't a proper place to store the wake-up flag, neither was query-machines because this isn't a static property of the machine object. This new API can then be used to store other dynamic machine properties that are scattered around the code ATM. More info at: https://lists.gnu.org/archive/html/qemu-devel/2018-05/msg04235.html Reported-by: Balamuruhan S <bala24@linux.vnet.ibm.com> Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com> --- hw/acpi/core.c | 1 + include/sysemu/sysemu.h | 1 + qapi/misc.json | 24 ++++++++++++++++++++++++ vl.c | 19 +++++++++++++++++++ 4 files changed, 45 insertions(+)