hv: add priority based scheduler

This patch adds a new priority based scheduler to support
vCPU scheduling based on their pre-configured priorities.
A vCPU can be running only if there is no higher priority
vCPU running on the same pCPU.

Tracked-On: #6571
Signed-off-by: Jie Deng <jie.deng@intel.com>

misc/config_tools/library/hv_cfg_lib.py

@@ -12,7 +12,7 @@ import board_cfg_lib
 
 ERR_LIST = {}
 N_Y = ['n', 'y']
-SCHEDULER_TYPE = ['SCHED_NOOP', 'SCHED_IORR', 'SCHED_BVT']
+SCHEDULER_TYPE = ['SCHED_NOOP', 'SCHED_IORR', 'SCHED_BVT', 'SCHED_PRIO']
 
 RANGE_DB = {
     'LOG_LEVEL':{'min':0,'max':6},

misc/config_tools/schema/config.xsd

@@ -400,6 +400,11 @@ Refer SDM 17.19.2 for details, and use with caution.</xs:documentation>
         <xs:documentation>Specify memory information for Service and User VMs.</xs:documentation>
       </xs:annotation>
     </xs:element>
+    <xs:element name="priority" type="PriorityType"  default="PRIO_LOW">
+      <xs:annotation>
+        <xs:documentation>Specify the VM vCPU priority for scheduling.</xs:documentation>
+      </xs:annotation>
+    </xs:element>
     <xs:element name="os_config" type="OSConfigurations" minOccurs="0">
       <xs:annotation>
         <xs:documentation>General information for host kernel, boot

misc/config_tools/schema/types.xsd

@@ -101,7 +101,7 @@ higher value (lower severity) are discarded.</xs:documentation>
 
 <xs:simpleType name="SchedulerType">
   <xs:annotation>
-    <xs:documentation>Three scheduler options are supported:
+    <xs:documentation>Four scheduler options are supported:
 
 - ``SCHED_NOOP``: The NOOP (No-Operation) scheduler means there is a
   strict 1 to 1 mapping between vCPUs and pCPUs.
@@ -113,6 +113,8 @@ higher value (lower severity) are discarded.</xs:documentation>
   earliest effective virtual time. *TODO: BVT scheduler will be built on
   top of a prioritized scheduling mechanism, i.e. higher priority threads
   get scheduled first, and same priority tasks are scheduled per BVT.*
+- ``SCHED_PRIO``: The priority based scheduler. vCPU scheduling will be based on
+  their pre-configured priorities.
 
 Read more about the available scheduling options in :ref:`cpu_sharing`.</xs:documentation>
   </xs:annotation>
@@ -120,6 +122,21 @@ Read more about the available scheduling options in :ref:`cpu_sharing`.</xs:docu
     <xs:enumeration value="SCHED_NOOP" />
     <xs:enumeration value="SCHED_IORR" />
     <xs:enumeration value="SCHED_BVT" />
+    <xs:enumeration value="SCHED_PRIO" />
+  </xs:restriction>
+</xs:simpleType>
+
+<xs:simpleType name="PriorityType">
+  <xs:annotation>
+    <xs:documentation>Two priorities are supported for priority based scheduler:
+
+- ``PRIO_LOW``: low priority for vCPU scheduling.
+- ``PRIO_HIGH``: high priority for vCPU scheduling.
+    </xs:documentation>
+  </xs:annotation>
+  <xs:restriction base="xs:string">
+    <xs:enumeration value="PRIO_LOW" />
+    <xs:enumeration value="PRIO_HIGH" />
   </xs:restriction>
 </xs:simpleType>
 

misc/config_tools/xforms/vm_configurations.c.xsl

@@ -18,6 +18,7 @@
     <xsl:value-of select="acrn:include('vuart.h')" />
     <xsl:value-of select="acrn:include('asm/pci_dev.h')" />
     <xsl:value-of select="acrn:include('asm/pgtable.h')" />
+    <xsl:value-of select="acrn:include('schedule.h')" />
 
     <xsl:apply-templates select="config-data/acrn-config" />
   </xsl:template>
@@ -67,6 +68,7 @@
       <xsl:value-of select="acrn:comment('Allow Service VM to reboot the system since it is the highest priority VM.')" />
       <xsl:value-of select="$newline" />
     </xsl:if>
+    <xsl:value-of select="acrn:initializer('vm_prio', priority)" />
     <xsl:apply-templates select="guest_flags" />
     <xsl:apply-templates select="clos" />
     <xsl:call-template name="cpu_affinity" />