From 0267f63a1fcfe60c69183274650cace0a4aba1f5 Mon Sep 17 00:00:00 2001

Message-Id: <0267f63a1fcfe60c69183274650cace0a4aba1f5@dist-git>

From: Peter Krempa <pkrempa@redhat.com>

Date: Wed, 24 Aug 2016 16:11:09 -0400

Subject: [PATCH] qemu: domain: Simplify return values of

 qemuDomainRefreshVcpuInfo

https://bugzilla.redhat.com/show_bug.cgi?id=1097930

https://bugzilla.redhat.com/show_bug.cgi?id=1224341

Call the vcpu thread info validation separately to decrease complexity

of returned values by qemuDomainRefreshVcpuInfo.

This function now returns 0 on success and -1 on error. Certain

failures of qemu to report data are still considered as success. Any

error reported now is fatal.

(cherry picked from commit 041f35340b949e4b4dbb8fbbbc12d69dfac734a6)

---

 src/qemu/qemu_domain.c  | 15 +++++----------

 src/qemu/qemu_driver.c  | 22 +++++++++++-----------

 src/qemu/qemu_process.c |  6 ++++++

 3 files changed, 22 insertions(+), 21 deletions(-)

diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c

index e087fe6..9cbf938 100644

--- a/src/qemu/qemu_domain.c

+++ b/src/qemu/qemu_domain.c

@@ -5676,10 +5676,10 @@ qemuDomainValidateVcpuInfo(virDomainObjPtr vm)

  * @vm: domain object

  * @asyncJob: current asynchronous job type

  *

- * Updates vCPU information private data of @vm.

+ * Updates vCPU information private data of @vm. Due to historical reasons this

+ * function returns success even if some data were not reported by qemu.

  *

- * Returns number of detected vCPU threads on success, -1 on error and reports

- * an appropriate error, -2 if the domain doesn't exist any more.

+ * Returns 0 on success and -1 on fatal error.

  */

 int

 qemuDomainRefreshVcpuInfo(virQEMUDriverPtr driver,

@@ -5727,10 +5727,8 @@ qemuDomainRefreshVcpuInfo(virQEMUDriverPtr driver,

     if (qemuDomainObjEnterMonitorAsync(driver, vm, asyncJob) < 0)

         return -1;

     ncpupids = qemuMonitorGetCPUInfo(qemuDomainGetMonitor(vm), &cpupids);

-    if (qemuDomainObjExitMonitor(driver, vm) < 0) {

-        ret = -2;

+    if (qemuDomainObjExitMonitor(driver, vm) < 0)

         goto cleanup;

-    }

     /* failure to get the VCPU <-> PID mapping or to execute the query

      * command will not be treated fatal as some versions of qemu don't

@@ -5750,10 +5748,7 @@ qemuDomainRefreshVcpuInfo(virQEMUDriverPtr driver,

             QEMU_DOMAIN_VCPU_PRIVATE(vcpu)->tid = 0;

     }

-    if (qemuDomainValidateVcpuInfo(vm) < 0)

-        goto cleanup;

-

-    ret = ncpupids;

+    ret = 0;

  cleanup:

     VIR_FREE(cpupids);

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c

index 040c638..1011bb8 100644

--- a/src/qemu/qemu_driver.c

+++ b/src/qemu/qemu_driver.c

@@ -4621,6 +4621,7 @@ qemuDomainHotplugAddVcpu(virQEMUDriverPtr driver,

 {

     qemuDomainObjPrivatePtr priv = vm->privateData;

     virDomainVcpuDefPtr vcpuinfo = virDomainDefGetVcpu(vm->def, vcpu);

+    qemuDomainVcpuPrivatePtr vcpupriv = QEMU_DOMAIN_VCPU_PRIVATE(vcpuinfo);

     int ret = -1;

     int rc;

     int oldvcpus = virDomainDefGetVcpus(vm->def);

@@ -4645,15 +4646,14 @@ qemuDomainHotplugAddVcpu(virQEMUDriverPtr driver,

     vcpuinfo->online = true;

-    if ((rc = qemuDomainRefreshVcpuInfo(driver, vm, QEMU_ASYNC_JOB_NONE)) <= 0) {

-        /* vcpu pids were not detected, skip setting of affinity */

-        if (rc == 0)

-            ret = 0;

-

+    if (qemuDomainRefreshVcpuInfo(driver, vm, QEMU_ASYNC_JOB_NONE) < 0)

         goto cleanup;

-    }

-    if (qemuProcessSetupVcpu(vm, vcpu) < 0)

+    if (qemuDomainValidateVcpuInfo(vm) < 0)

+        goto cleanup;

+

+    if (vcpupriv->tid > 0 &&

+        qemuProcessSetupVcpu(vm, vcpu) < 0)

         goto cleanup;

     ret = 0;

@@ -4695,11 +4695,11 @@ qemuDomainHotplugDelVcpu(virQEMUDriverPtr driver,

         goto cleanup;

     }

-    if ((rc = qemuDomainRefreshVcpuInfo(driver, vm, QEMU_ASYNC_JOB_NONE)) < 0) {

-        /* rollback only if domain didn't exit */

-        if (rc == -2)

-            goto cleanup;

+    if (qemuDomainRefreshVcpuInfo(driver, vm, QEMU_ASYNC_JOB_NONE) < 0)

+        goto cleanup;

+    if (qemuDomainValidateVcpuInfo(vm) < 0) {

+        /* rollback vcpu count if the setting has failed */

         virDomainAuditVcpu(vm, oldvcpus, oldvcpus - 1, "update", false);

         vcpuinfo->online = true;

         goto cleanup;

diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c

index 6ff5da5..cdfd1e3 100644

--- a/src/qemu/qemu_process.c

+++ b/src/qemu/qemu_process.c

@@ -5196,6 +5196,9 @@ qemuProcessLaunch(virConnectPtr conn,

     if (qemuDomainRefreshVcpuInfo(driver, vm, asyncJob) < 0)

         goto cleanup;

+    if (qemuDomainValidateVcpuInfo(vm) < 0)

+        goto cleanup;

+

     VIR_DEBUG("Detecting IOThread PIDs");

     if (qemuProcessDetectIOThreadPIDs(driver, vm, asyncJob) < 0)

         goto cleanup;

@@ -5990,6 +5993,9 @@ int qemuProcessAttach(virConnectPtr conn ATTRIBUTE_UNUSED,

     if (qemuDomainRefreshVcpuInfo(driver, vm, QEMU_ASYNC_JOB_NONE) < 0)

         goto error;

+    if (qemuDomainValidateVcpuInfo(vm) < 0)

+        goto error;

+

     VIR_DEBUG("Detecting IOThread PIDs");

     if (qemuProcessDetectIOThreadPIDs(driver, vm, QEMU_ASYNC_JOB_NONE) < 0)

         goto error;

-- 

2.10.0