[libvirt] [PATCH v2 3/3] libxl: correctly handle affinity reset in virDomainPinVcpu[Flags]

[Dario Faggioli]

By actually removing the <vcpupin> element (from within the
<cputune> section) from the XML, rather than jus update it with
a fully set vcpu affinity mask.

Signed-off-by: Dario Faggioli <dario.faggioli at citrix.com>
Cc: Jim Fehlig <jfehlig at suse.com>
Cc: Ian Jackson <Ian.Jackson at eu.citrix.com>
---
 src/libxl/libxl_driver.c |   18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/src/libxl/libxl_driver.c b/src/libxl/libxl_driver.c
index 8528106..4705870 100644
--- a/src/libxl/libxl_driver.c
+++ b/src/libxl/libxl_driver.c
@@ -2365,6 +2365,7 @@ libxlDomainPinVcpuFlags(virDomainPtr dom, unsigned int vcpu,
     libxlDriverPrivatePtr driver = dom->conn->privateData;
     libxlDriverConfigPtr cfg = libxlDriverConfigGet(driver);
     virDomainDefPtr targetDef = NULL;
+    virBitmapPtr pcpumap = NULL;
     virDomainObjPtr vm;
     int ret = -1;
 
@@ -2393,6 +2394,10 @@ libxlDomainPinVcpuFlags(virDomainPtr dom, unsigned int vcpu,
 
     sa_assert(targetDef);
 
+    pcpumap = virBitmapNewData(cpumap, maplen);
+    if (!pcpumap)
+        goto cleanup;
+
     if (flags & VIR_DOMAIN_AFFECT_LIVE) {
         libxl_bitmap map = { .size = maplen, .map = cpumap };
         libxlDomainObjPrivatePtr priv;
@@ -2406,6 +2411,17 @@ libxlDomainPinVcpuFlags(virDomainPtr dom, unsigned int vcpu,
         }
     }
 
+    /* full bitmap means reset the settings (if any). */
+    if (virBitmapIsAllSet(pcpumap)) {
+        if (virDomainVcpuPinDel(targetDef, vcpu) < 0) {
+            virReportError(VIR_ERR_INTERNAL_ERROR,
+                           _("Failed to delete vcpupin xml for vcpu '%d'"),
+                           vcpu);
+            goto cleanup;
+        }
+        goto out;
+    }
+
     if (!targetDef->cputune.vcpupin) {
         if (VIR_ALLOC(targetDef->cputune.vcpupin) < 0)
             goto cleanup;
@@ -2421,6 +2437,7 @@ libxlDomainPinVcpuFlags(virDomainPtr dom, unsigned int vcpu,
         goto cleanup;
     }
 
+out:
     ret = 0;
 
     if (flags & VIR_DOMAIN_AFFECT_LIVE) {
@@ -2432,6 +2449,7 @@ libxlDomainPinVcpuFlags(virDomainPtr dom, unsigned int vcpu,
 cleanup:
     if (vm)
         virObjectUnlock(vm);
+    virBitmapFree(pcpumap);
     virObjectUnref(cfg);
     return ret;
 }