[libvirt] [PATCHv2 1/3] qemu, lxc: Change host CPU detection logic.
The drivers for QEMU and LXC use virNodeGetInfo to determine the
number of host CPUs. This approach can lead to a wrong (too small)
number if one or more CPUs are offline.
It is better to use nodeGetCPUCount on Linux hosts.
---
V2 Changes:
Use nodeGetCPUCount as suggested by Eric, nodeGetCPUMap is too
"heavyweight".
src/lxc/lxc_controller.c | 8 +++-----
src/qemu/qemu_driver.c | 14 +++++---------
src/qemu/qemu_process.c | 8 +++-----
3 files changed, 11 insertions(+), 19 deletions(-)
diff --git a/src/lxc/lxc_controller.c b/src/lxc/lxc_controller.c
index a41c903..ed3d3d0 100644
--- a/src/lxc/lxc_controller.c
+++ b/src/lxc/lxc_controller.c
@@ -492,17 +492,15 @@ static int virLXCControllerSetupNUMAPolicy(virLXCControllerPtr
ctrl)
static int virLXCControllerSetupCpuAffinity(virLXCControllerPtr ctrl)
{
int hostcpus, maxcpu = CPU_SETSIZE;
- virNodeInfo nodeinfo;
virBitmapPtr cpumap, cpumapToSet;
VIR_DEBUG("Setting CPU affinity");
- if (nodeGetInfo(NULL, &nodeinfo) < 0)
- return -1;
-
/* setaffinity fails if you set bits for CPUs which
* aren't present, so we have to limit ourselves */
- hostcpus = VIR_NODEINFO_MAXCPUS(nodeinfo);
+ if ((hostcpus = nodeGetCPUCount()) < 0)
+ return -1;
+
if (maxcpu > hostcpus)
maxcpu = hostcpus;
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 3980c10..6ae33d3 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -4097,7 +4097,6 @@ qemudDomainGetVcpuPinInfo(virDomainPtr dom,
struct qemud_driver *driver = dom->conn->privateData;
virDomainObjPtr vm = NULL;
- virNodeInfo nodeinfo;
virDomainDefPtr targetDef = NULL;
int ret = -1;
int maxcpu, hostcpus, vcpu, pcpu;
@@ -4133,9 +4132,9 @@ qemudDomainGetVcpuPinInfo(virDomainPtr dom,
/* Coverity didn't realize that targetDef must be set if we got here. */
sa_assert(targetDef);
- if (nodeGetInfo(dom->conn, &nodeinfo) < 0)
+ if ((hostcpus = nodeGetCPUCount()) < 0)
goto cleanup;
- hostcpus = VIR_NODEINFO_MAXCPUS(nodeinfo);
+
maxcpu = maplen * 8;
if (maxcpu > hostcpus)
maxcpu = hostcpus;
@@ -4348,7 +4347,6 @@ qemudDomainGetEmulatorPinInfo(virDomainPtr dom,
{
struct qemud_driver *driver = dom->conn->privateData;
virDomainObjPtr vm = NULL;
- virNodeInfo nodeinfo;
virDomainDefPtr targetDef = NULL;
int ret = -1;
int maxcpu, hostcpus, pcpu;
@@ -4381,9 +4379,9 @@ qemudDomainGetEmulatorPinInfo(virDomainPtr dom,
/* Coverity didn't realize that targetDef must be set if we got here. */
sa_assert(targetDef);
- if (nodeGetInfo(dom->conn, &nodeinfo) < 0)
+ if ((hostcpus = nodeGetCPUCount()) < 0)
goto cleanup;
- hostcpus = VIR_NODEINFO_MAXCPUS(nodeinfo);
+
maxcpu = maplen * 8;
if (maxcpu > hostcpus)
maxcpu = hostcpus;
@@ -4425,7 +4423,6 @@ qemudDomainGetVcpus(virDomainPtr dom,
int maplen) {
struct qemud_driver *driver = dom->conn->privateData;
virDomainObjPtr vm;
- virNodeInfo nodeinfo;
int i, v, maxcpu, hostcpus;
int ret = -1;
qemuDomainObjPrivatePtr priv;
@@ -4451,10 +4448,9 @@ qemudDomainGetVcpus(virDomainPtr dom,
priv = vm->privateData;
- if (nodeGetInfo(dom->conn, &nodeinfo) < 0)
+ if ((hostcpus = nodeGetCPUCount()) < 0)
goto cleanup;
- hostcpus = VIR_NODEINFO_MAXCPUS(nodeinfo);
maxcpu = maplen * 8;
if (maxcpu > hostcpus)
maxcpu = hostcpus;
diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
index 3ac5282..74e43b8 100644
--- a/src/qemu/qemu_process.c
+++ b/src/qemu/qemu_process.c
@@ -1902,15 +1902,13 @@ qemuPrepareCpumap(struct qemud_driver *driver,
virBitmapPtr nodemask)
{
int i, hostcpus, maxcpu = QEMUD_CPUMASK_LEN;
- virNodeInfo nodeinfo;
virBitmapPtr cpumap = NULL;
- if (nodeGetInfo(NULL, &nodeinfo) < 0)
- return NULL;
-
/* setaffinity fails if you set bits for CPUs which
* aren't present, so we have to limit ourselves */
- hostcpus = VIR_NODEINFO_MAXCPUS(nodeinfo);
+ if ((hostcpus = nodeGetCPUCount()) < 0)
+ return NULL;
+
if (maxcpu > hostcpus)
maxcpu = hostcpus;
--
1.7.12.4