Re: [libvirt] [PATCH] Add 'Hybrid-Suspend' power management discovery for the host

On Thu, Nov 24, 2011 at 02:22:41PM +0530, Srivatsa S. Bhat wrote: > Some systems support a feature known as 'Hybrid-Suspend', apart from the > usual system-wide sleep states such as Suspend-to-RAM (S3) or Suspend-to-Disk > (S4). Add the functionality to discover this power management feature and > export it in the capabilities XML under the <power_management> tag. > > This addition was suggested in [1]. > > References: > 1. http://www.redhat.com/archives/libvir-list/2011-November/msg01298.html > > Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat(a)linux.vnet.ibm.com&gt; > --- > > docs/formatcaps.html.in | 12 +++-- > docs/schemas/capability.rng | 5 ++ > src/conf/capabilities.c | 2 - > src/util/util.c | 99 ++++++++++++++++++++++++++++++------------- > src/util/util.h | 8 ++- > 5 files changed, 88 insertions(+), 38 deletions(-) > > diff --git a/docs/formatcaps.html.in b/docs/formatcaps.html.in > index ce6f9a6..c5fb925 100644 > --- a/docs/formatcaps.html.in > +++ b/docs/formatcaps.html.in > @@ -31,6 +31,7 @@ BIOS you will see</p> > &lt;power_management&gt; > &lt;S3/&gt; > &lt;S4/&gt; > + &lt;Hybrid-Suspend/&gt; > &lt;power_management/&gt; > &lt;/host&gt;</span> > > @@ -70,11 +71,12 @@ the host platform, but other information may be available, it shows the CPU arch > topology, model name, and additional features which are not included in the model but the > CPU provides them. Features of the chip are shown within the feature block (the block is > similar to what you will find in a Xen fully virtualized domain description). Further, > -the power management features supported by the host are shown, such as Suspend-to-RAM (S3) > -and Suspend-to-Disk (S4). In case the query for power management features succeeded but the > -host does not support any such feature, then an empty &lt;power_management/&gt; > -tag will be shown. Otherwise, if the query itself failed, no such tag will > -be displayed (i.e., there will not be any power_management block or empty tag in the XML).</p> > +the power management features supported by the host are shown, such as Suspend-to-RAM (S3), > +Suspend-to-Disk (S4) and Hybrid-Suspend (a combination of S3 and S4). > +In case the query for power management features succeeded but the host does not support > +any such feature, then an empty &lt;power_management/&gt; tag will be shown. Otherwise, > +if the query itself failed, no such tag will be displayed (i.e., there will not be any > +power_management block or empty tag in the XML).</p> > <p>The second block (in blue) indicates the paravirtualization support of the > Xen support, you will see the os_type of xen to indicate a paravirtual > kernel, then architecture information and potential features.</p> > diff --git a/docs/schemas/capability.rng b/docs/schemas/capability.rng > index 645769e..6cf2188 100644 > --- a/docs/schemas/capability.rng > +++ b/docs/schemas/capability.rng > @@ -121,6 +121,11 @@ > <empty/> > </element> > </optional> > + <optional> > + <element name='Hybrid-Suspend'> > + <empty/> > + </element> > + </optional> > </interleave> > </element> > </define> > diff --git a/src/conf/capabilities.c b/src/conf/capabilities.c > index 87b60b0..8468861 100644 > --- a/src/conf/capabilities.c > +++ b/src/conf/capabilities.c > @@ -35,7 +35,7 @@ > #define VIR_FROM_THIS VIR_FROM_CAPABILITIES > > VIR_ENUM_IMPL(virHostPMCapability, VIR_HOST_PM_LAST, > - "S3", "S4") > + "S3", "S4", "Hybrid-Suspend") > > /** > * virCapabilitiesNew: > diff --git a/src/util/util.c b/src/util/util.c > index ce697fb..ccd1a0e 100644 > --- a/src/util/util.c > +++ b/src/util/util.c > @@ -2623,47 +2623,50 @@ virTypedParameterArrayClear(virTypedParameterPtr params, int nparams) > } > > /** > - * Get the Power Management Capabilities of the host system. > - * The script 'pm-is-supported' (from the pm-utils package) is run > - * to find out all the power management features supported by the host, > - * such as Suspend-to-RAM (S3) and Suspend-to-Disk (S4). > + * virDiscoverHostPMFeature: > + * @bitmask: The bitmask which should be populated with the result of > + * the query > + * @feature: The power management feature to check whether it is supported > + * by the host. Values could be: > + * VIR_HOST_PM_S3 for Suspend-to-RAM > + * VIR_HOST_PM_S4 for Suspend-to-Disk > + * VIR_HOST_PM_HYBRID_SUSPEND for Hybrid-Suspend > * > - * @bitmask: Pointer to the bitmask which will be set appropriately to > - * indicate all the supported host power management features. > + * Run the script 'pm-is-supported' (from the pm-utils package) > + * to find out if @feature is supported by the host. > * > - * Returns 0 if the query was successful, -1 upon failure. > + * Returns 0 if the query was successful, -1 on failure. > */ > int > -virGetPMCapabilities(unsigned int *bitmask) > +virDiscoverHostPMFeature(unsigned int *bitmask, unsigned int feature) > { > - int ret = -1; > - int status; > virCommandPtr cmd; > + int status; > + int ret = -1; > > - *bitmask = 0; > - > - /* Check support for Suspend-to-RAM (S3) */ > - cmd = virCommandNewArgList("pm-is-supported", "--suspend", NULL); > - if (virCommandRun(cmd, &status) < 0) > - goto cleanup; > - > - /* Check return code of command == 0 for success > - * (i.e., the PM capability is supported) > - */ > - if (status == 0) > - *bitmask |= 1U << VIR_HOST_PM_S3; > - virCommandFree(cmd); > + switch (feature) { > + case VIR_HOST_PM_S3: > + cmd = virCommandNewArgList("pm-is-supported", "--suspend", NULL); > + break; > + case VIR_HOST_PM_S4: > + cmd = virCommandNewArgList("pm-is-supported", "--hibernate", NULL); > + break; > + case VIR_HOST_PM_HYBRID_SUSPEND: > + cmd = virCommandNewArgList("pm-is-supported", "--suspend-hybrid", NULL); > + break; > + default: > + return ret; > + } > > - /* Check support for Suspend-to-Disk (S4) */ > - cmd = virCommandNewArgList("pm-is-supported", "--hibernate", NULL); > if (virCommandRun(cmd, &status) < 0) > goto cleanup; > > - /* Check return code of command == 0 for success > - * (i.e., the PM capability is supported) > - */ > + /* > + * Check return code of command == 0 for success > + * (i.e., the PM capability is supported) > + */ > if (status == 0) > - *bitmask |= 1U << VIR_HOST_PM_S4; > + *bitmask |= 1U << feature; > > ret = 0; > > @@ -2671,3 +2674,41 @@ cleanup: > virCommandFree(cmd); > return ret; > } > + > +/** > + * virGetPMCapabilities: > + * > + * Get the Power Management Capabilities that the host system supports, > + * such as Suspend-to-RAM (S3), Suspend-to-Disk (S4) and Hybrid-Suspend > + * (a combination of S3 and S4). > + * > + * @bitmask: Pointer to the bitmask which will be set appropriately to > + * indicate all the supported host power management features. > + * > + * Returns 0 if the query was successful, -1 on failure. > + */ > +int > +virGetPMCapabilities(unsigned int *bitmask) > +{ > + int ret; > + > + *bitmask = 0; > + > + /* Check support for Suspend-to-RAM (S3) */ > + ret = virDiscoverHostPMFeature(bitmask, VIR_HOST_PM_S3); > + if (ret < 0) > + return -1; > + > + /* Check support for Suspend-to-Disk (S4) */ > + ret = virDiscoverHostPMFeature(bitmask, VIR_HOST_PM_S4); > + if (ret < 0) > + return -1; > + > + /* Check support for Hybrid-Suspend */ > + ret = virDiscoverHostPMFeature(bitmask, VIR_HOST_PM_HYBRID_SUSPEND); > + if (ret < 0) > + return -1; > + > + return 0; > +} > + > diff --git a/src/util/util.h b/src/util/util.h > index 5afcf58..eda60d2 100644 > --- a/src/util/util.h > +++ b/src/util/util.h > @@ -264,14 +264,16 @@ void virTypedParameterArrayClear(virTypedParameterPtr params, int nparams); > /* Power Management Capabilities of the host system */ > > enum virHostPMCapability { > - VIR_HOST_PM_S3, /* Suspend-to-RAM */ > - VIR_HOST_PM_S4, /* Suspend-to-Disk */ > + VIR_HOST_PM_S3, /* Suspend-to-RAM */ > + VIR_HOST_PM_S4, /* Suspend-to-Disk */ > + VIR_HOST_PM_HYBRID_SUSPEND, /* Hybrid-Suspend */ > > VIR_HOST_PM_LAST > }; > > VIR_ENUM_DECL(virHostPMCapability) > > -int virGetPMCapabilities(unsigned int *); > +int virDiscoverHostPMFeature(unsigned int *bitmask, unsigned int feature); > +int virGetPMCapabilities(unsigned int *bitmask); ACK, that looks reasonable, I actually have machines with and without that mode. I had to cleanup the patch a bit to apply to the documentation and pass "make synatx-check" though, I will push later, thanks,