lib: Add API to set individual vcpu usage in the guest via guest agent

To allow finer-grained control of vcpu state using guest agent this API
can be used to individually set the state of the vCPU.

This will allow to better control NUMA enabled guests and/or test
various vCPU configurations.

diff --git a/include/libvirt/libvirt-domain.h b/include/libvirt/libvirt-domain.h
index 5605a94969fe6b8533f0ec06617c45dd40219a4f..5b80b8524621c2c2b7d9678e7a1db96a0d940164 100644 (file)
--- a/include/libvirt/libvirt-domain.h
+++ b/include/libvirt/libvirt-domain.h
@@ -4102,4 +4102,9 @@ int virDomainGetGuestVcpus(virDomainPtr domain,
                            unsigned int *nparams,
                            unsigned int flags);
 
+int virDomainSetGuestVcpus(virDomainPtr domain,
+                           const char *cpumap,
+                           int state,
+                           unsigned int flags);
+
 #endif /* __VIR_LIBVIRT_DOMAIN_H__ */

diff --git a/src/driver-hypervisor.h b/src/driver-hypervisor.h
index 93af2b664e9d1350168edde5ab2046b76d7cd4cf..5cd1fdf4f339cef9c51e15061eb6f7db00c478e0 100644 (file)
--- a/src/driver-hypervisor.h
+++ b/src/driver-hypervisor.h
@@ -1245,6 +1245,12 @@ typedef int
                              unsigned int *nparams,
                              unsigned int flags);
 
+typedef int
+(*virDrvDomainSetGuestVcpus)(virDomainPtr domain,
+                             const char *cpumap,
+                             int state,
+                             unsigned int flags);
+
 typedef struct _virHypervisorDriver virHypervisorDriver;
 typedef virHypervisorDriver *virHypervisorDriverPtr;
 
@@ -1482,6 +1488,7 @@ struct _virHypervisorDriver {
     virDrvConnectUnregisterCloseCallback connectUnregisterCloseCallback;
     virDrvDomainMigrateStartPostCopy domainMigrateStartPostCopy;
     virDrvDomainGetGuestVcpus domainGetGuestVcpus;
+    virDrvDomainSetGuestVcpus domainSetGuestVcpus;
 };
 
 

diff --git a/src/libvirt-domain.c b/src/libvirt-domain.c
index eb995b570f5b726d6e613a7d92eb8442b33e92bc..508520efd6c55a562c0a4dd9b4032e28e72f6174 100644 (file)
--- a/src/libvirt-domain.c
+++ b/src/libvirt-domain.c
@@ -11891,3 +11891,58 @@ virDomainGetGuestVcpus(virDomainPtr domain,
     virDispatchError(domain->conn);
     return -1;
 }
+
+
+/**
+ * virDomainSetGuestVcpus:
+ * @domain: pointer to domain object
+ * @cpumap: text representation of a bitmap of vcpus to set
+ * @state: 0 to disable/1 to enable cpus described by @cpumap
+ * @flags: currently unused, callers shall pass 0
+ *
+ * Sets state of individual vcpus described by @cpumap via guest agent. Other
+ * vcpus are not modified.
+ *
+ * This API requires the VM to run. Various hypervisors or guest agent
+ * implementation may limit to operate on just 1 vCPU per call.
+ *
+ * @cpumap is a list of vCPU numbers. Its syntax is a comma separated list and
+ * a special markup using '-' and '^' (ex. '0-4', '0-3,^2'). The '-' denotes
+ * the range and the '^' denotes exclusive. The expression is sequentially
+ * evaluated, so "0-15,^8" is identical to "9-14,0-7,15" but not identical to
+ * "^8,0-15".
+ *
+ * Note that OSes (notably Linux) may require vCPU 0 to stay online to support
+ * low-level features a S3 sleep.
+ *
+ * Returns 0 on success, -1 on error.
+ */
+int
+virDomainSetGuestVcpus(virDomainPtr domain,
+                       const char *cpumap,
+                       int state,
+                       unsigned int flags)
+{
+    VIR_DOMAIN_DEBUG(domain, "cpumap='%s' state=%x flags=%x",
+                     NULLSTR(cpumap), state, flags);
+
+    virResetLastError();
+
+    virCheckDomainReturn(domain, -1);
+    virCheckNonNullArgGoto(cpumap, error);
+
+    if (domain->conn->driver->domainSetGuestVcpus) {
+        int ret;
+        ret = domain->conn->driver->domainSetGuestVcpus(domain, cpumap, state,
+                                                        flags);
+        if (ret < 0)
+            goto error;
+        return ret;
+    }
+
+    virReportUnsupportedError();
+
+ error:
+    virDispatchError(domain->conn);
+    return -1;
+}

diff --git a/src/libvirt_public.syms b/src/libvirt_public.syms
index 30801c5a5430057deb5dce50aefaff4ba14946de..b6d2dfdba3271211561772ea4b708946f98b1ea4 100644 (file)
--- a/src/libvirt_public.syms
+++ b/src/libvirt_public.syms
@@ -737,6 +737,7 @@ LIBVIRT_2.0.0 {
         virConnectStoragePoolEventRegisterAny;
         virConnectStoragePoolEventDeregisterAny;
         virDomainGetGuestVcpus;
+        virDomainSetGuestVcpus;
 } LIBVIRT_1.3.3;
 
 # .... define new API here using predicted next version number ....

diff --git a/src/remote/remote_driver.c b/src/remote/remote_driver.c
index 6a580c6c01d0a99a728efab85dab8f7b197225ea..3f9d812fc98889269d3802353b7b1fa112c1b0ff 100644 (file)
--- a/src/remote/remote_driver.c
+++ b/src/remote/remote_driver.c
@@ -7982,6 +7982,7 @@ static virHypervisorDriver hypervisor_driver = {
     .connectUnregisterCloseCallback = remoteConnectUnregisterCloseCallback, /* 1.3.2 */
     .domainMigrateStartPostCopy = remoteDomainMigrateStartPostCopy, /* 1.3.3 */
     .domainGetGuestVcpus = remoteDomainGetGuestVcpus, /* 2.0.0 */
+    .domainSetGuestVcpus = remoteDomainSetGuestVcpus, /* 2.0.0 */
 };
 
 static virNetworkDriver network_driver = {

diff --git a/src/remote/remote_protocol.x b/src/remote/remote_protocol.x
index f72918d2e36bfad8080a9ea95cd7cb1aab633581..d11bfdf69912c10a08e7fc483dd605fcbecd6980 100644 (file)
--- a/src/remote/remote_protocol.x
+++ b/src/remote/remote_protocol.x
@@ -3304,6 +3304,13 @@ struct remote_domain_get_guest_vcpus_ret {
     remote_typed_param params<REMOTE_DOMAIN_GUEST_VCPU_PARAMS_MAX>; /* alloc@1@unsigned int@2 */
 };
 
+struct remote_domain_set_guest_vcpus_args {
+    remote_nonnull_domain dom;
+    remote_nonnull_string cpumap;
+    int state;
+    unsigned int flags;
+};
+
 
 /*----- Protocol. -----*/
 
@@ -5858,5 +5865,11 @@ enum remote_procedure {
      * @generate: both
      * @acl: domain:write
      */
-    REMOTE_PROC_DOMAIN_GET_GUEST_VCPUS = 371
+    REMOTE_PROC_DOMAIN_GET_GUEST_VCPUS = 371,
+
+    /**
+     * @generate: both
+     * @acl: domain:write
+     */
+    REMOTE_PROC_DOMAIN_SET_GUEST_VCPUS = 372
 };

diff --git a/src/remote_protocol-structs b/src/remote_protocol-structs
index 4e603dbe520adfae6a7cadf4425ef50e647f65b7..0d89b15c213a68d45351e1f7af064ed263e700dd 100644 (file)
--- a/src/remote_protocol-structs
+++ b/src/remote_protocol-structs
@@ -2761,6 +2761,12 @@ struct remote_domain_get_guest_vcpus_ret {
                 remote_typed_param * params_val;
         } params;
 };
+struct remote_domain_set_guest_vcpus_args {
+        remote_nonnull_domain      dom;
+        remote_nonnull_string      cpumap;
+        int                        state;
+        u_int                      flags;
+};
 enum remote_procedure {
         REMOTE_PROC_CONNECT_OPEN = 1,
         REMOTE_PROC_CONNECT_CLOSE = 2,
@@ -3133,4 +3139,5 @@ enum remote_procedure {
         REMOTE_PROC_CONNECT_STORAGE_POOL_EVENT_DEREGISTER_ANY = 369,
         REMOTE_PROC_STORAGE_POOL_EVENT_LIFECYCLE = 370,
         REMOTE_PROC_DOMAIN_GET_GUEST_VCPUS = 371,
+        REMOTE_PROC_DOMAIN_SET_GUEST_VCPUS = 372,
 };