In order to set CPU cfs period using cgroup v2 'cpu.max' interface
we need to load the current value of CPU cfs quota first because
format of 'cpu.max' interface is '$quota $period' and in order to
change 'period' we need to write 'quota' as well. Writing only one
number changes only 'quota'.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
---
src/util/vircgroupv2.c | 68 ++++++++++++++++++++++++++++++++++++++++++
1 file changed, 68 insertions(+)
diff --git a/src/util/vircgroupv2.c b/src/util/vircgroupv2.c
index 6cecfb9741..92fe825795 100644
--- a/src/util/vircgroupv2.c
+++ b/src/util/vircgroupv2.c
@@ -1327,6 +1327,72 @@ virCgroupV2GetCpuShares(virCgroupPtr group,
}
+static int
+virCgroupV2SetCpuCfsPeriod(virCgroupPtr group,
+ unsigned long long cfs_period)
+{
+ VIR_AUTOFREE(char *) value = NULL;
+ VIR_AUTOFREE(char *) str = NULL;
+ char *tmp;
+
+ /* The cfs_period should be greater or equal than 1ms, and less or equal
+ * than 1s.
+ */
+ if (cfs_period < 1000 || cfs_period > 1000000) {
+ virReportError(VIR_ERR_INVALID_ARG,
+ _("cfs_period '%llu' must be in range (1000, 1000000)"),
+ cfs_period);
+ return -1;
+ }
+
+ if (virCgroupGetValueStr(group, VIR_CGROUP_CONTROLLER_CPU,
+ "cpu.max", &str) < 0) {
+ return -1;
+ }
+
+ if (!(tmp = strchr(str, ' '))) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Invalid 'cpu.max' data."));
+ return -1;
+ }
+ *tmp = '\n';
+
+ if (virAsprintf(&value, "%s %llu", str, cfs_period) < 0)
+ return -1;
+
+ return virCgroupSetValueStr(group, VIR_CGROUP_CONTROLLER_CPU,
+ "cpu.max", value);
+}
+
+
+static int
+virCgroupV2GetCpuCfsPeriod(virCgroupPtr group,
+ unsigned long long *cfs_period)
+{
+ VIR_AUTOFREE(char *) str = NULL;
+ char *tmp;
+
+ if (virCgroupGetValueStr(group, VIR_CGROUP_CONTROLLER_CPU,
+ "cpu.max", &str) < 0) {
+ return -1;
+ }
+
+ if (!(tmp = strchr(str, ' '))) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Invalid 'cpu.max' data."));
+ return -1;
+ }
+
+ if (virStrToLong_ull(tmp, NULL, 10, cfs_period) < 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ _("Failed to parse value '%s' from cpu.max."), str);
+ return -1;
+ }
+
+ return 0;
+}
+
+
virCgroupBackend virCgroupV2Backend = {
.type = VIR_CGROUP_BACKEND_TYPE_V2,
@@ -1377,6 +1443,8 @@ virCgroupBackend virCgroupV2Backend = {
.setCpuShares = virCgroupV2SetCpuShares,
.getCpuShares = virCgroupV2GetCpuShares,
+ .setCpuCfsPeriod = virCgroupV2SetCpuCfsPeriod,
+ .getCpuCfsPeriod = virCgroupV2GetCpuCfsPeriod,
};
--
2.17.1
--
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