src: Introduce virCgroupFreezerState enum

So far, only vircgroupv1 implements freezer controller related
callbacks and both work with strings ("THAWED", "FROZEN",
"FREEZING"). This works well with v1 but with CGroupsV2 there are
just two states and they are represented by a number.

Therefore, introduce an enum and implement enum <-> string
conversion for each backend separately.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Pavel Hrdina <pavel@hrdina.info>

diff --git a/src/lxc/lxc_driver.c b/src/lxc/lxc_driver.c
index c0a93c0444bb48075075289149f3f00118c0ef25..3ec6d298bd871aec5d9667f74cae2dd7243bd4e7 100644 (file)
--- a/src/lxc/lxc_driver.c
+++ b/src/lxc/lxc_driver.c
@@ -2495,11 +2495,12 @@ static int lxcFreezeContainer(virDomainObj *vm)
     int check_interval = 1; /* In milliseconds */
     int exp = 10;
     int waited_time = 0;
-    g_autofree char *state = NULL;
     virLXCDomainObjPrivate *priv = vm->privateData;
 
     while (waited_time < timeout) {
+        virCgroupFreezerState state;
         int r;
+
         /*
          * Writing "FROZEN" to the "freezer.state" freezes the group,
          * i.e., the container, temporarily transiting "FREEZING" state.
@@ -2507,7 +2508,8 @@ static int lxcFreezeContainer(virDomainObj *vm)
          * to "FROZEN".
          * (see linux-2.6/Documentation/cgroups/freezer-subsystem.txt)
          */
-        r = virCgroupSetFreezerState(priv->cgroup, "FROZEN");
+        r = virCgroupSetFreezerState(priv->cgroup,
+                                     VIR_CGROUP_FREEZER_STATE_FROZEN);
 
         /*
          * Returning EBUSY explicitly indicates that the group is
@@ -2540,9 +2542,9 @@ static int lxcFreezeContainer(virDomainObj *vm)
             VIR_DEBUG("Reading freezer.state failed with errno: %d", r);
             goto error;
         }
-        VIR_DEBUG("Read freezer.state: %s", state);
+        VIR_DEBUG("Read freezer.state: %d", state);
 
-        if (STREQ(state, "FROZEN"))
+        if (state == VIR_CGROUP_FREEZER_STATE_FROZEN)
             return 0;
 
         waited_time += check_interval;
@@ -2563,7 +2565,7 @@ static int lxcFreezeContainer(virDomainObj *vm)
      * activate the group again and return an error.
      * This is likely to fall the group back again gracefully.
      */
-    virCgroupSetFreezerState(priv->cgroup, "THAWED");
+    virCgroupSetFreezerState(priv->cgroup, VIR_CGROUP_FREEZER_STATE_THAWED);
     return -1;
 }
 
@@ -2643,7 +2645,8 @@ static int lxcDomainResume(virDomainPtr dom)
                        "%s", _("domain is already running"));
         goto endjob;
     } else if (state == VIR_DOMAIN_PAUSED) {
-        if (virCgroupSetFreezerState(priv->cgroup, "THAWED") < 0) {
+        if (virCgroupSetFreezerState(priv->cgroup,
+                                     VIR_CGROUP_FREEZER_STATE_THAWED) < 0) {
             virReportError(VIR_ERR_OPERATION_FAILED,
                            "%s", _("Resume operation failed"));
             goto endjob;

diff --git a/src/lxc/lxc_process.c b/src/lxc/lxc_process.c
index c731b28871b18329e633c42f2141d22063208d9f..e22f77ef83caffae1e5f71d1b48c432b710aab84 100644 (file)
--- a/src/lxc/lxc_process.c
+++ b/src/lxc/lxc_process.c
@@ -860,7 +860,8 @@ int virLXCProcessStop(virLXCDriver *driver,
             return -1;
         }
 
-        if (virCgroupSetFreezerState(priv->cgroup, "THAWED") < 0) {
+        if (virCgroupSetFreezerState(priv->cgroup,
+                                     VIR_CGROUP_FREEZER_STATE_THAWED) < 0) {
             virReportError(VIR_ERR_OPERATION_FAILED, "%s",
                            _("Unable to thaw all processes"));
 

diff --git a/src/util/vircgroup.c b/src/util/vircgroup.c
index 3d66d3acb26654d041d793302349c3a4c0e32716..e7c93cd0100bffcd68bb9939d765802cd32f0b41 100644 (file)
--- a/src/util/vircgroup.c
+++ b/src/util/vircgroup.c
@@ -2902,7 +2902,8 @@ virCgroupGetCpuacctStat(virCgroup *group, unsigned long long *user,
 
 
 int
-virCgroupSetFreezerState(virCgroup *group, const char *state)
+virCgroupSetFreezerState(virCgroup *group,
+                         virCgroupFreezerState state)
 {
     virCgroup *parent = virCgroupGetNested(group);
 
@@ -2912,7 +2913,8 @@ virCgroupSetFreezerState(virCgroup *group, const char *state)
 
 
 int
-virCgroupGetFreezerState(virCgroup *group, char **state)
+virCgroupGetFreezerState(virCgroup *group,
+                         virCgroupFreezerState *state)
 {
     virCgroup *parent = virCgroupGetNested(group);
 
@@ -3725,7 +3727,7 @@ virCgroupGetDomainTotalCpuStats(virCgroup *group G_GNUC_UNUSED,
 
 int
 virCgroupSetFreezerState(virCgroup *group G_GNUC_UNUSED,
-                         const char *state G_GNUC_UNUSED)
+                         virCgroupFreezerState state G_GNUC_UNUSED)
 {
     virReportSystemError(ENOSYS, "%s",
                          _("Control groups not supported on this platform"));
@@ -3735,7 +3737,7 @@ virCgroupSetFreezerState(virCgroup *group G_GNUC_UNUSED,
 
 int
 virCgroupGetFreezerState(virCgroup *group G_GNUC_UNUSED,
-                         char **state G_GNUC_UNUSED)
+                         virCgroupFreezerState **state G_GNUC_UNUSED)
 {
     virReportSystemError(ENOSYS, "%s",
                          _("Control groups not supported on this platform"));

diff --git a/src/util/vircgroup.h b/src/util/vircgroup.h
index 2a7aa3306c8d3c90f0d3d1a75b21e3117bb37bbf..6d0aa11e90f7ac83cc69ced41dcf56b2539858ae 100644 (file)
--- a/src/util/vircgroup.h
+++ b/src/util/vircgroup.h
@@ -254,8 +254,16 @@ int virCgroupGetCpuacctPercpuUsage(virCgroup *group, char **usage);
 int virCgroupGetCpuacctStat(virCgroup *group, unsigned long long *user,
                             unsigned long long *sys);
 
-int virCgroupSetFreezerState(virCgroup *group, const char *state);
-int virCgroupGetFreezerState(virCgroup *group, char **state);
+typedef enum {
+    VIR_CGROUP_FREEZER_STATE_THAWED,
+    VIR_CGROUP_FREEZER_STATE_FROZEN,
+    VIR_CGROUP_FREEZER_STATE_FREEZING,
+
+    VIR_CGROUP_FREEZER_STATE_LAST
+} virCgroupFreezerState;
+
+int virCgroupSetFreezerState(virCgroup *group, virCgroupFreezerState state);
+int virCgroupGetFreezerState(virCgroup *group, virCgroupFreezerState *state);
 
 int virCgroupSetCpusetMems(virCgroup *group, const char *mems);
 int virCgroupGetCpusetMems(virCgroup *group, char **mems);

diff --git a/src/util/vircgroupbackend.h b/src/util/vircgroupbackend.h
index ee2f6c1ec7904491b440b60151deeeafaa3568c2..6effe49df6db1d6306611d39f2a784025d727ccb 100644 (file)
--- a/src/util/vircgroupbackend.h
+++ b/src/util/vircgroupbackend.h
@@ -339,11 +339,11 @@ typedef int
 
 typedef int
 (*virCgroupSetFreezerStateCB)(virCgroup *group,
-                              const char *state);
+                              virCgroupFreezerState state);
 
 typedef int
 (*virCgroupGetFreezerStateCB)(virCgroup *group,
-                              char **state);
+                              virCgroupFreezerState *state);
 
 typedef int
 (*virCgroupSetCpusetMemsCB)(virCgroup *group,

diff --git a/src/util/vircgroupv1.c b/src/util/vircgroupv1.c
index c1f0562249f30a61e64c9435690c32a6cb0b3f42..ac05531f7da7e6c117932ba7d06f2a432a7d16b4 100644 (file)
--- a/src/util/vircgroupv1.c
+++ b/src/util/vircgroupv1.c
@@ -2049,23 +2049,49 @@ virCgroupV1GetCpuacctStat(virCgroup *group,
 }
 
 
+VIR_ENUM_DECL(virCgroupFreezerState);
+VIR_ENUM_IMPL(virCgroupFreezerState,
+              VIR_CGROUP_FREEZER_STATE_LAST,
+              "THAWED",
+              "FROZEN",
+              "FREEZING"
+);
+
 static int
 virCgroupV1SetFreezerState(virCgroup *group,
-                           const char *state)
+                           virCgroupFreezerState state)
 {
+    const char *stateStr = virCgroupFreezerStateTypeToString(state);
+
     return virCgroupSetValueStr(group,
                                 VIR_CGROUP_CONTROLLER_FREEZER,
-                                "freezer.state", state);
+                                "freezer.state", stateStr);
 }
 
 
 static int
 virCgroupV1GetFreezerState(virCgroup *group,
-                           char **state)
+                           virCgroupFreezerState *state)
 {
-    return virCgroupGetValueStr(group,
-                                VIR_CGROUP_CONTROLLER_FREEZER,
-                                "freezer.state", state);
+    g_autofree char *stateStr = NULL;
+    int s;
+
+    if (virCgroupGetValueStr(group,
+                             VIR_CGROUP_CONTROLLER_FREEZER,
+                             "freezer.state", &stateStr) < 0) {
+        return -1;
+    }
+
+    s = virCgroupFreezerStateTypeFromString(stateStr);
+    if (s < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR,
+                       _("Unknown value of freezer controller: %1$s"),
+                       stateStr);
+        return -1;
+    }
+
+    *state = s;
+    return 0;
 }