[libvirt] [PATCH 1/3] qemu: Move memory limit computation to a reusable function
---
src/qemu/qemu_cgroup.c | 21 ++-------------------
src/qemu/qemu_domain.c | 29 +++++++++++++++++++++++++++++
src/qemu/qemu_domain.h | 2 ++
3 files changed, 33 insertions(+), 19 deletions(-)
diff --git a/src/qemu/qemu_cgroup.c b/src/qemu/qemu_cgroup.c
index 5f54ca6..22bf78e 100644
--- a/src/qemu/qemu_cgroup.c
+++ b/src/qemu/qemu_cgroup.c
@@ -461,9 +461,7 @@ static int
qemuSetupMemoryCgroup(virDomainObjPtr vm)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
- unsigned long long hard_limit;
int rc;
- int i;
if (!virCgroupHasController(priv->cgroup,VIR_CGROUP_CONTROLLER_MEMORY)) {
if (vm->def->mem.hard_limit != 0 ||
@@ -477,23 +475,8 @@ qemuSetupMemoryCgroup(virDomainObjPtr vm)
}
}
- hard_limit = vm->def->mem.hard_limit;
- if (!hard_limit) {
- /* If there is no hard_limit set, set a reasonable one to avoid
- * system thrashing caused by exploited qemu. A 'reasonable
- * limit' has been chosen:
- * (1 + k) * (domain memory + total video memory) + (32MB for
- * cache per each disk) + F
- * where k = 0.5 and F = 200MB. The cache for disks is important as
- * kernel cache on the host side counts into the RSS limit. */
- hard_limit = vm->def->mem.max_balloon;
- for (i = 0; i < vm->def->nvideos; i++)
- hard_limit += vm->def->videos[i]->vram;
- hard_limit = hard_limit * 1.5 + 204800;
- hard_limit += vm->def->ndisks * 32768;
- }
-
- rc = virCgroupSetMemoryHardLimit(priv->cgroup, hard_limit);
+ rc = virCgroupSetMemoryHardLimit(priv->cgroup,
+ qemuDomainMemoryLimit(vm->def));
if (rc != 0) {
virReportSystemError(-rc,
_("Unable to set memory hard limit for domain
%s"),
diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index 8d79066..77b94ec 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -2181,3 +2181,32 @@ cleanup:
virObjectUnref(cfg);
return ret;
}
+
+
+unsigned long long
+qemuDomainMemoryLimit(virDomainDefPtr def)
+{
+ unsigned long long mem;
+ int i;
+
+ if (def->mem.hard_limit) {
+ mem = def->mem.hard_limit;
+ } else {
+ /* If there is no hard_limit set, compute a reasonable one to avoid
+ * system thrashing caused by exploited qemu. A 'reasonable
+ * limit' has been chosen:
+ * (1 + k) * (domain memory + total video memory) + (32MB for
+ * cache per each disk) + F
+ * where k = 0.5 and F = 200MB. The cache for disks is important as
+ * kernel cache on the host side counts into the RSS limit.
+ */
+ mem = def->mem.max_balloon;
+ for (i = 0; i < def->nvideos; i++)
+ mem += def->videos[i]->vram;
+ mem *= 1.5;
+ mem += def->ndisks * 32768;
+ mem += 204800;
+ }
+
+ return mem;
+}
diff --git a/src/qemu/qemu_domain.h b/src/qemu/qemu_domain.h
index 068a4c3..ade2095 100644
--- a/src/qemu/qemu_domain.h
+++ b/src/qemu/qemu_domain.h
@@ -351,4 +351,6 @@ extern virDomainXMLPrivateDataCallbacks
virQEMUDriverPrivateDataCallbacks;
extern virDomainXMLNamespace virQEMUDriverDomainXMLNamespace;
extern virDomainDefParserConfig virQEMUDriverDomainDefParserConfig;
+unsigned long long qemuDomainMemoryLimit(virDomainDefPtr def);
+
#endif /* __QEMU_DOMAIN_H__ */
--
1.8.2.1