memtune: Let virsh know the unlimited value for memory tunables

Display or set unlimited values for memory parameters. Unlimited is
represented by INT64_MAX in memory cgroup.
Signed-off-by: NNikunj A. Dadhania <nikunj@linux.vnet.ibm.com>
Reported-by: NJustin Clift <jclift@redhat.com>

include/libvirt/libvirt.h.in

@@ -696,6 +696,7 @@ typedef enum {
  */
 
 #define VIR_DOMAIN_MEMORY_FIELD_LENGTH 80
+#define VIR_DOMAIN_MEMORY_PARAM_UNLIMITED (INT64_MAX >> 10)
 
 /**
  * VIR_DOMAIN_MEMORY_HARD_LIMIT:

src/lxc/lxc_driver.c

@@ -815,7 +815,7 @@ static int lxcDomainGetMemoryParameters(virDomainPtr dom,
     int i;
     virCgroupPtr cgroup = NULL;
     virDomainObjPtr vm = NULL;
-    unsigned long val;
+    unsigned long long val;
     int ret = -1;
     int rc;
 

src/qemu/qemu_driver.c

@@ -7036,7 +7036,7 @@ static int qemuDomainGetMemoryParameters(virDomainPtr dom,
     int i;
     virCgroupPtr group = NULL;
     virDomainObjPtr vm = NULL;
-    unsigned long val;
+    unsigned long long val;
     int ret = -1;
     int rc;
 

src/util/cgroup.c

@@ -355,8 +355,6 @@ static int virCgroupSetValueU64(virCgroupPtr group,
 }
 
 
-#if 0
-/* This is included for completeness, but not yet used */
 
 static int virCgroupSetValueI64(virCgroupPtr group,
                                 int controller,
@@ -376,6 +374,8 @@ static int virCgroupSetValueI64(virCgroupPtr group,
     return rc;
 }
 
+#if 0
+/* This is included for completeness, but not yet used */
 static int virCgroupGetValueI64(virCgroupPtr group,
                                 int controller,
                                 const char *key,
@@ -858,12 +858,22 @@ int virCgroupForDomain(virCgroupPtr driver ATTRIBUTE_UNUSED,
  *
  * Returns: 0 on success
  */
-int virCgroupSetMemory(virCgroupPtr group, unsigned long kb)
+int virCgroupSetMemory(virCgroupPtr group, unsigned long long kb)
 {
-    return virCgroupSetValueU64(group,
-                                VIR_CGROUP_CONTROLLER_MEMORY,
-                                "memory.limit_in_bytes",
-                                kb << 10);
+    unsigned long long maxkb = VIR_DOMAIN_MEMORY_PARAM_UNLIMITED;
+
+    if (kb > maxkb)
+        return -EINVAL;
+    else if (kb == maxkb)
+        return virCgroupSetValueI64(group,
+                                    VIR_CGROUP_CONTROLLER_MEMORY,
+                                    "memory.limit_in_bytes",
+                                    -1);
+    else
+        return virCgroupSetValueU64(group,
+                                    VIR_CGROUP_CONTROLLER_MEMORY,
+                                    "memory.limit_in_bytes",
+                                    kb << 10);
 }
 
 /**
@@ -894,7 +904,7 @@ int virCgroupGetMemoryUsage(virCgroupPtr group, unsigned long *kb)
  *
  * Returns: 0 on success
  */
-int virCgroupSetMemoryHardLimit(virCgroupPtr group, unsigned long kb)
+int virCgroupSetMemoryHardLimit(virCgroupPtr group, unsigned long long kb)
 {
     return virCgroupSetMemory(group, kb);
 }
@@ -907,7 +917,7 @@ int virCgroupSetMemoryHardLimit(virCgroupPtr group, unsigned long kb)
  *
  * Returns: 0 on success
  */
-int virCgroupGetMemoryHardLimit(virCgroupPtr group, unsigned long *kb)
+int virCgroupGetMemoryHardLimit(virCgroupPtr group, unsigned long long *kb)
 {
     long long unsigned int limit_in_bytes;
     int ret;
@@ -915,7 +925,7 @@ int virCgroupGetMemoryHardLimit(virCgroupPtr group, unsigned long *kb)
                                VIR_CGROUP_CONTROLLER_MEMORY,
                                "memory.limit_in_bytes", &limit_in_bytes);
     if (ret == 0)
-        *kb = (unsigned long) limit_in_bytes >> 10;
+        *kb = limit_in_bytes >> 10;
     return ret;
 }
 
@@ -927,12 +937,22 @@ int virCgroupGetMemoryHardLimit(virCgroupPtr group, unsigned long *kb)
  *
  * Returns: 0 on success
  */
-int virCgroupSetMemorySoftLimit(virCgroupPtr group, unsigned long kb)
+int virCgroupSetMemorySoftLimit(virCgroupPtr group, unsigned long long kb)
 {
-    return virCgroupSetValueU64(group,
-                                VIR_CGROUP_CONTROLLER_MEMORY,
-                                "memory.soft_limit_in_bytes",
-                                kb << 10);
+    unsigned long long maxkb = VIR_DOMAIN_MEMORY_PARAM_UNLIMITED;
+
+    if (kb > maxkb)
+        return -EINVAL;
+    else if (kb == maxkb)
+        return virCgroupSetValueI64(group,
+                                    VIR_CGROUP_CONTROLLER_MEMORY,
+                                    "memory.soft_limit_in_bytes",
+                                    -1);
+    else
+        return virCgroupSetValueU64(group,
+                                    VIR_CGROUP_CONTROLLER_MEMORY,
+                                    "memory.soft_limit_in_bytes",
+                                    kb << 10);
 }
 
 
@@ -944,7 +964,7 @@ int virCgroupSetMemorySoftLimit(virCgroupPtr group, unsigned long kb)
  *
  * Returns: 0 on success
  */
-int virCgroupGetMemorySoftLimit(virCgroupPtr group, unsigned long *kb)
+int virCgroupGetMemorySoftLimit(virCgroupPtr group, unsigned long long *kb)
 {
     long long unsigned int limit_in_bytes;
     int ret;
@@ -952,7 +972,7 @@ int virCgroupGetMemorySoftLimit(virCgroupPtr group, unsigned long *kb)
                                VIR_CGROUP_CONTROLLER_MEMORY,
                                "memory.soft_limit_in_bytes", &limit_in_bytes);
     if (ret == 0)
-        *kb = (unsigned long) limit_in_bytes >> 10;
+        *kb = limit_in_bytes >> 10;
     return ret;
 }
 
@@ -964,12 +984,22 @@ int virCgroupGetMemorySoftLimit(virCgroupPtr group, unsigned long *kb)
  *
  * Returns: 0 on success
  */
-int virCgroupSetSwapHardLimit(virCgroupPtr group, unsigned long kb)
+int virCgroupSetSwapHardLimit(virCgroupPtr group, unsigned long long kb)
 {
-    return virCgroupSetValueU64(group,
-                                VIR_CGROUP_CONTROLLER_MEMORY,
-                                "memory.memsw.limit_in_bytes",
-                                kb << 10);
+    unsigned long long maxkb = VIR_DOMAIN_MEMORY_PARAM_UNLIMITED;
+
+    if (kb > maxkb)
+        return -EINVAL;
+    else if (kb == maxkb)
+        return virCgroupSetValueI64(group,
+                                    VIR_CGROUP_CONTROLLER_MEMORY,
+                                    "memory.memsw.limit_in_bytes",
+                                    -1);
+    else
+        return virCgroupSetValueU64(group,
+                                    VIR_CGROUP_CONTROLLER_MEMORY,
+                                    "memory.memsw.limit_in_bytes",
+                                    kb << 10);
 }
 
 /**
@@ -980,7 +1010,7 @@ int virCgroupSetSwapHardLimit(virCgroupPtr group, unsigned long kb)
  *
  * Returns: 0 on success
  */
-int virCgroupGetSwapHardLimit(virCgroupPtr group, unsigned long *kb)
+int virCgroupGetSwapHardLimit(virCgroupPtr group, unsigned long long *kb)
 {
     long long unsigned int limit_in_bytes;
     int ret;
@@ -988,7 +1018,7 @@ int virCgroupGetSwapHardLimit(virCgroupPtr group, unsigned long *kb)
                                VIR_CGROUP_CONTROLLER_MEMORY,
                                "memory.memsw.limit_in_bytes", &limit_in_bytes);
     if (ret == 0)
-        *kb = (unsigned long) limit_in_bytes >> 10;
+        *kb = limit_in_bytes >> 10;
     return ret;
 }
 

src/util/cgroup.h

@@ -40,15 +40,15 @@ int virCgroupForDomain(virCgroupPtr driver,
 
 int virCgroupAddTask(virCgroupPtr group, pid_t pid);
 
-int virCgroupSetMemory(virCgroupPtr group, unsigned long kb);
+int virCgroupSetMemory(virCgroupPtr group, unsigned long long kb);
 int virCgroupGetMemoryUsage(virCgroupPtr group, unsigned long *kb);
 
-int virCgroupSetMemoryHardLimit(virCgroupPtr group, unsigned long kb);
-int virCgroupGetMemoryHardLimit(virCgroupPtr group, unsigned long *kb);
-int virCgroupSetMemorySoftLimit(virCgroupPtr group, unsigned long kb);
-int virCgroupGetMemorySoftLimit(virCgroupPtr group, unsigned long *kb);
-int virCgroupSetSwapHardLimit(virCgroupPtr group, unsigned long kb);
-int virCgroupGetSwapHardLimit(virCgroupPtr group, unsigned long *kb);
+int virCgroupSetMemoryHardLimit(virCgroupPtr group, unsigned long long kb);
+int virCgroupGetMemoryHardLimit(virCgroupPtr group, unsigned long long *kb);
+int virCgroupSetMemorySoftLimit(virCgroupPtr group, unsigned long long kb);
+int virCgroupGetMemorySoftLimit(virCgroupPtr group, unsigned long long *kb);
+int virCgroupSetSwapHardLimit(virCgroupPtr group, unsigned long long kb);
+int virCgroupGetSwapHardLimit(virCgroupPtr group, unsigned long long *kb);
 
 int virCgroupDenyAllDevices(virCgroupPtr group);
 

tools/virsh.c

@@ -3007,8 +3007,11 @@ cmdMemtune(vshControl * ctl, const vshCmd * cmd)
                              params[i].value.l);
                     break;
                 case VIR_DOMAIN_MEMORY_PARAM_ULLONG:
-                    vshPrint(ctl, "%-15s: %llu\n", params[i].field,
-                             params[i].value.ul);
+                    if (params[i].value.ul == VIR_DOMAIN_MEMORY_PARAM_UNLIMITED)
+                        vshPrint(ctl, "%-15s: unlimited\n", params[i].field);
+                    else
+                        vshPrint(ctl, "%-15s: %llu kB\n", params[i].field,
+                                 params[i].value.ul);
                     break;
                 case VIR_DOMAIN_MEMORY_PARAM_DOUBLE:
                     vshPrint(ctl, "%-15s: %f\n", params[i].field,
@@ -3059,6 +3062,10 @@ cmdMemtune(vshControl * ctl, const vshCmd * cmd)
                         sizeof(temp->field));
                 min_guarantee = 0;
             }
+
+            /* If the user has passed -1, we interpret it as unlimited */
+            if (temp->value.ul == -1)
+                temp->value.ul = VIR_DOMAIN_MEMORY_PARAM_UNLIMITED;
         }
         if (virDomainSetMemoryParameters(dom, params, nparams, 0) != 0)
             vshError(ctl, "%s", _("Unable to change memory parameters"));