vcpu: improve vcpu support in xen command line

This patch series focuses on xendConfigVersion 2 (xm_internal) and 3
(xend_internal), but leaves out changes for xenapi drivers.

See this link for more details about vcpu_avail for xm usage.
http://lists.xensource.com/archives/html/xen-devel/2009-11/msg01061.html

This relies on the fact that def->maxvcpus can be at most 32 with xen.

* src/xen/xend_internal.c (xenDaemonParseSxpr)
(sexpr_to_xend_domain_info, xenDaemonFormatSxpr): Use vcpu_avail
when current vcpus is less than maximum.
* src/xen/xm_internal.c (xenXMDomainConfigParse)
(xenXMDomainConfigFormat): Likewise.
* tests/xml2sexprdata/xml2sexpr-pv-vcpus.sexpr: New file.
* tests/sexpr2xmldata/sexpr2xml-pv-vcpus.sexpr: Likewise.
* tests/sexpr2xmldata/sexpr2xml-pv-vcpus.xml: Likewise.
* tests/xmconfigdata/test-paravirt-vcpu.cfg: Likewise.
* tests/xmconfigdata/test-paravirt-vcpu.xml: Likewise.
* tests/xml2sexprtest.c (mymain): New test.
* tests/sexpr2xmltest.c (mymain): Likewise.
* tests/xmconfigtest.c (mymain): Likewise.

src/xen/xend_internal.c

@@ -44,6 +44,7 @@
 #include "xen_hypervisor.h"
 #include "xs_internal.h" /* To extract VNC port & Serial console TTY */
 #include "memory.h"
+#include "count-one-bits.h"
 
 /* required for cpumap_t */
 #include <xen/dom0_ops.h>
@@ -2191,7 +2192,9 @@ xenDaemonParseSxpr(virConnectPtr conn,
     }
 
     def->maxvcpus = sexpr_int(root, "domain/vcpus");
-    def->vcpus = def->maxvcpus;
+    def->vcpus = count_one_bits(sexpr_int(root, "domain/vcpu_avail"));
+    if (!def->vcpus || def->maxvcpus < def->vcpus)
+        def->vcpus = def->maxvcpus;
 
     tmp = sexpr_node(root, "domain/on_poweroff");
     if (tmp != NULL) {
@@ -2433,7 +2436,7 @@ sexpr_to_xend_domain_info(virDomainPtr domain, const struct sexpr *root,
                           virDomainInfoPtr info)
 {
     const char *flags;
-
+    int vcpus;
 
     if ((root == NULL) || (info == NULL))
         return (-1);
@@ -2464,7 +2467,11 @@ sexpr_to_xend_domain_info(virDomainPtr domain, const struct sexpr *root,
             info->state = VIR_DOMAIN_NOSTATE;
     }
     info->cpuTime = sexpr_float(root, "domain/cpu_time") * 1000000000;
-    info->nrVirtCpu = sexpr_int(root, "domain/vcpus");
+    vcpus = sexpr_int(root, "domain/vcpus");
+    info->nrVirtCpu = count_one_bits(sexpr_int(root, "domain/vcpu_avail"));
+    if (!info->nrVirtCpu || vcpus < info->nrVirtCpu)
+        info->nrVirtCpu = vcpus;
+
     return (0);
 }
 
@@ -5668,6 +5675,9 @@ xenDaemonFormatSxpr(virConnectPtr conn,
     virBufferVSprintf(&buf, "(memory %lu)(maxmem %lu)",
                       def->mem.cur_balloon/1024, def->mem.max_balloon/1024);
     virBufferVSprintf(&buf, "(vcpus %u)", def->maxvcpus);
+    /* Computing the vcpu_avail bitmask works because MAX_VIRT_CPUS is 32.  */
+    if (def->vcpus < def->maxvcpus)
+        virBufferVSprintf(&buf, "(vcpu_avail %u)", (1U << def->vcpus) - 1);
 
     if (def->cpumask) {
         char *ranges = virDomainCpuSetFormat(def->cpumask, def->cpumasklen);
@@ -5763,6 +5773,9 @@ xenDaemonFormatSxpr(virConnectPtr conn,
                 virBufferVSprintf(&buf, "(kernel '%s')", def->os.loader);
 
             virBufferVSprintf(&buf, "(vcpus %u)", def->maxvcpus);
+            if (def->vcpus < def->maxvcpus)
+                virBufferVSprintf(&buf, "(vcpu_avail %u)",
+                                  (1U << def->vcpus) - 1);
 
             for (i = 0 ; i < def->os.nBootDevs ; i++) {
                 switch (def->os.bootDevs[i]) {

src/xen/xm_internal.c

@@ -46,6 +46,7 @@
 #include "util.h"
 #include "memory.h"
 #include "logging.h"
+#include "count-one-bits.h"
 
 #define VIR_FROM_THIS VIR_FROM_XENXM
 
@@ -772,10 +773,12 @@ xenXMDomainConfigParse(virConnectPtr conn, virConfPtr conf) {
     def->mem.max_balloon *= 1024;
 
     if (xenXMConfigGetULong(conf, "vcpus", &count, 1) < 0 ||
-        (unsigned short) count != count)
+        MAX_VIRT_CPUS < count)
         goto cleanup;
     def->maxvcpus = count;
-    def->vcpus = def->maxvcpus;
+    if (xenXMConfigGetULong(conf, "vcpu_avail", &count, -1) < 0)
+        goto cleanup;
+    def->vcpus = MIN(count_one_bits(count), def->maxvcpus);
 
     if (xenXMConfigGetString(conf, "cpus", &str, NULL) < 0)
         goto cleanup;
@@ -2246,6 +2249,9 @@ virConfPtr xenXMDomainConfigFormat(virConnectPtr conn,
 
     if (xenXMConfigSetInt(conf, "vcpus", def->maxvcpus) < 0)
         goto no_memory;
+    if (def->vcpus < def->maxvcpus &&
+        xenXMConfigSetInt(conf, "vcpu_avail", (1U << def->vcpus) - 1) < 0)
+        goto no_memory;
 
     if ((def->cpumask != NULL) &&
         ((cpus = virDomainCpuSetFormat(def->cpumask,

tests/sexpr2xmldata/sexpr2xml-pv-vcpus.sexpr

+(domain (domid 6)(name 'pvtest')(memory 420)(maxmem 420)(vcpus 4)(vcpu_avail 3)(uuid '596a5d2171f48fb2e068e2386a5c413e')(on_poweroff 'destroy')(on_reboot 'destroy')(on_crash 'destroy')(image (linux (kernel '/var/lib/xen/vmlinuz.2Dn2YT')(ramdisk '/var/lib/xen/initrd.img.0u-Vhq')(args ' method=http://download.fedora.devel.redhat.com/pub/fedora/linux/core/test/5.91/x86_64/os  ')))(device (vbd (dev 'xvda')(uname 'file:/root/some.img')(mode 'w'))))

tests/sexpr2xmldata/sexpr2xml-pv-vcpus.xml

+<domain type='xen' id='6'>
+  <name>pvtest</name>
+  <uuid>596a5d21-71f4-8fb2-e068-e2386a5c413e</uuid>
+  <memory>430080</memory>
+  <currentMemory>430080</currentMemory>
+  <vcpu current='2'>4</vcpu>
+  <os>
+    <type>linux</type>
+    <kernel>/var/lib/xen/vmlinuz.2Dn2YT</kernel>
+    <initrd>/var/lib/xen/initrd.img.0u-Vhq</initrd>
+    <cmdline> method=http://download.fedora.devel.redhat.com/pub/fedora/linux/core/test/5.91/x86_64/os  </cmdline>
+  </os>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>destroy</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <disk type='file' device='disk'>
+      <driver name='file'/>
+      <source file='/root/some.img'/>
+      <target dev='xvda' bus='xen'/>
+    </disk>
+    <console type='pty'>
+      <target type='xen' port='0'/>
+    </console>
+  </devices>
+</domain>

tests/sexpr2xmltest.c

@@ -132,6 +132,7 @@ mymain(int argc, char **argv)
     DO_TEST("pv-vfb-type-crash", "pv-vfb-type-crash", 3);
     DO_TEST("fv-autoport", "fv-autoport", 3);
     DO_TEST("pv-bootloader", "pv-bootloader", 1);
+    DO_TEST("pv-vcpus", "pv-vcpus", 1);
 
     DO_TEST("disk-file", "disk-file", 2);
     DO_TEST("disk-block", "disk-block", 2);

tests/xmconfigdata/test-paravirt-vcpu.cfg

+name = "XenGuest1"
+uuid = "c7a5fdb0-cdaf-9455-926a-d65c16db1809"
+maxmem = 579
+memory = 394
+vcpus = 4
+vcpu_avail = 3
+bootloader = "/usr/bin/pygrub"
+on_poweroff = "destroy"
+on_reboot = "restart"
+on_crash = "restart"
+sdl = 0
+vnc = 1
+vncunused = 1
+vnclisten = "127.0.0.1"
+vncpasswd = "123poi"
+disk = [ "phy:/dev/HostVG/XenGuest1,xvda,w" ]
+vif = [ "mac=00:16:3e:66:94:9c,bridge=br0,script=vif-bridge" ]

tests/xmconfigdata/test-paravirt-vcpu.xml

+<domain type='xen'>
+  <name>XenGuest1</name>
+  <uuid>c7a5fdb0-cdaf-9455-926a-d65c16db1809</uuid>
+  <memory>592896</memory>
+  <currentMemory>403456</currentMemory>
+  <vcpu current='2'>4</vcpu>
+  <bootloader>/usr/bin/pygrub</bootloader>
+  <os>
+    <type arch='i686' machine='xenpv'>linux</type>
+  </os>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>restart</on_crash>
+  <devices>
+    <disk type='block' device='disk'>
+      <driver name='phy'/>
+      <source dev='/dev/HostVG/XenGuest1'/>
+      <target dev='xvda' bus='xen'/>
+    </disk>
+    <interface type='bridge'>
+      <mac address='00:16:3e:66:94:9c'/>
+      <source bridge='br0'/>
+      <script path='vif-bridge'/>
+    </interface>
+    <console type='pty'>
+      <target type='xen' port='0'/>
+    </console>
+    <input type='mouse' bus='xen'/>
+    <graphics type='vnc' port='-1' autoport='yes' listen='127.0.0.1' passwd='123poi'/>
+  </devices>
+</domain>

tests/xmconfigtest.c

@@ -210,6 +210,7 @@ mymain(int argc, char **argv)
     DO_TEST("paravirt-new-pvfb-vncdisplay", 3);
     DO_TEST("paravirt-net-e1000", 3);
     DO_TEST("paravirt-net-vifname", 3);
+    DO_TEST("paravirt-vcpu", 2);
     DO_TEST("fullvirt-old-cdrom", 1);
     DO_TEST("fullvirt-new-cdrom", 2);
     DO_TEST("fullvirt-utc", 2);

tests/xml2sexprdata/xml2sexpr-pv-vcpus.sexpr

+(vm (name 'pvtest')(memory 420)(maxmem 420)(vcpus 4)(vcpu_avail 3)(uuid '596a5d21-71f4-8fb2-e068-e2386a5c413e')(on_poweroff 'destroy')(on_reboot 'destroy')(on_crash 'destroy')(image (linux (kernel '/var/lib/xen/vmlinuz.2Dn2YT')(ramdisk '/var/lib/xen/initrd.img.0u-Vhq')(args ' method=http://download.fedora.devel.redhat.com/pub/fedora/linux/core/test/5.91/x86_64/os  ')))(device (vbd (dev 'xvda')(uname 'file:/root/some.img')(mode 'w'))))
\ No newline at end of file

tests/xml2sexprtest.c

@@ -118,6 +118,7 @@ mymain(int argc, char **argv)
     DO_TEST("pv-vfb-new", "pv-vfb-new", "pvtest", 3);
     DO_TEST("pv-vfb-new-auto", "pv-vfb-new-auto", "pvtest", 3);
     DO_TEST("pv-bootloader", "pv-bootloader", "pvtest", 1);
+    DO_TEST("pv-vcpus", "pv-vcpus", "pvtest", 1);
 
     DO_TEST("disk-file", "disk-file", "pvtest", 2);
     DO_TEST("disk-block", "disk-block", "pvtest", 2);