util: vircgroup: move virCgroupGetValueStr out of virCgroupGetValueForBlkDev

If we need to get a path of specific file and we need to check its
existence before we use it then we can reuse that path to get value
for specific device.  This way we will not build the path again in
virCgroupGetValueForBlkDev.
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

src/util/vircgroup.c

@@ -533,20 +533,14 @@ virCgroupGetValueStr(virCgroupPtr group,
 
 
 int
-virCgroupGetValueForBlkDev(virCgroupPtr group,
-                           int controller,
-                           const char *key,
+virCgroupGetValueForBlkDev(const char *str,
                            const char *path,
                            char **value)
 {
     VIR_AUTOFREE(char *) prefix = NULL;
-    VIR_AUTOFREE(char *) str = NULL;
     char **lines = NULL;
     int ret = -1;
 
-    if (virCgroupGetValueStr(group, controller, key, &str) < 0)
-        goto error;
-
     if (!(prefix = virCgroupGetBlockDevString(path)))
         goto error;
 

src/util/vircgrouppriv.h

@@ -98,10 +98,8 @@ int virCgroupPartitionEscape(char **path);
 
 char *virCgroupGetBlockDevString(const char *path);
 
-int virCgroupGetValueForBlkDev(virCgroupPtr group,
-                               int controller,
-                               const char *key,
-                               const char *path,
+int virCgroupGetValueForBlkDev(const char *str,
+                               const char *devPath,
                                char **value);
 
 int virCgroupNew(pid_t pid,

src/util/vircgroupv1.c

@@ -1181,12 +1181,16 @@ virCgroupV1GetBlkioDeviceWeight(virCgroupPtr group,
                                 unsigned int *weight)
 {
     VIR_AUTOFREE(char *) str = NULL;
+    VIR_AUTOFREE(char *) value = NULL;
 
-    if (virCgroupGetValueForBlkDev(group,
-                                   VIR_CGROUP_CONTROLLER_BLKIO,
-                                   "blkio.weight_device",
-                                   path,
-                                   &str) < 0)
+    if (virCgroupGetValueStr(group,
+                             VIR_CGROUP_CONTROLLER_BLKIO,
+                             "blkio.weight_device",
+                             &value) < 0) {
+        return -1;
+    }
+
+    if (virCgroupGetValueForBlkDev(value, path, &str) < 0)
         return -1;
 
     if (!str) {
@@ -1229,12 +1233,16 @@ virCgroupV1GetBlkioDeviceReadIops(virCgroupPtr group,
                                   unsigned int *riops)
 {
     VIR_AUTOFREE(char *) str = NULL;
+    VIR_AUTOFREE(char *) value = NULL;
 
-    if (virCgroupGetValueForBlkDev(group,
-                                   VIR_CGROUP_CONTROLLER_BLKIO,
-                                   "blkio.throttle.read_iops_device",
-                                   path,
-                                   &str) < 0)
+    if (virCgroupGetValueStr(group,
+                             VIR_CGROUP_CONTROLLER_BLKIO,
+                             "blkio.throttle.read_iops_device",
+                             &value) < 0) {
+        return -1;
+    }
+
+    if (virCgroupGetValueForBlkDev(value, path, &str) < 0)
         return -1;
 
     if (!str) {
@@ -1277,12 +1285,16 @@ virCgroupV1GetBlkioDeviceWriteIops(virCgroupPtr group,
                                    unsigned int *wiops)
 {
     VIR_AUTOFREE(char *) str = NULL;
+    VIR_AUTOFREE(char *) value = NULL;
 
-    if (virCgroupGetValueForBlkDev(group,
-                                   VIR_CGROUP_CONTROLLER_BLKIO,
-                                   "blkio.throttle.write_iops_device",
-                                   path,
-                                   &str) < 0)
+    if (virCgroupGetValueStr(group,
+                             VIR_CGROUP_CONTROLLER_BLKIO,
+                             "blkio.throttle.write_iops_device",
+                             &value) < 0) {
+        return -1;
+    }
+
+    if (virCgroupGetValueForBlkDev(value, path, &str) < 0)
         return -1;
 
     if (!str) {
@@ -1325,12 +1337,16 @@ virCgroupV1GetBlkioDeviceReadBps(virCgroupPtr group,
                                  unsigned long long *rbps)
 {
     VIR_AUTOFREE(char *) str = NULL;
+    VIR_AUTOFREE(char *) value = NULL;
+
+    if (virCgroupGetValueStr(group,
+                             VIR_CGROUP_CONTROLLER_BLKIO,
+                             "blkio.throttle.read_bps_device",
+                             &value) < 0) {
+        return -1;
+    }
 
-    if (virCgroupGetValueForBlkDev(group,
-                                   VIR_CGROUP_CONTROLLER_BLKIO,
-                                   "blkio.throttle.read_bps_device",
-                                   path,
-                                   &str) < 0)
+    if (virCgroupGetValueForBlkDev(value, path, &str) < 0)
         return -1;
 
     if (!str) {
@@ -1373,12 +1389,16 @@ virCgroupV1GetBlkioDeviceWriteBps(virCgroupPtr group,
                                   unsigned long long *wbps)
 {
     VIR_AUTOFREE(char *) str = NULL;
+    VIR_AUTOFREE(char *) value = NULL;
+
+    if (virCgroupGetValueStr(group,
+                             VIR_CGROUP_CONTROLLER_BLKIO,
+                             "blkio.throttle.write_bps_device",
+                             &value) < 0) {
+        return -1;
+    }
 
-    if (virCgroupGetValueForBlkDev(group,
-                                   VIR_CGROUP_CONTROLLER_BLKIO,
-                                   "blkio.throttle.write_bps_device",
-                                   path,
-                                   &str) < 0)
+    if (virCgroupGetValueForBlkDev(value, path, &str) < 0)
         return -1;
 
     if (!str) {

src/util/vircgroupv2.c

@@ -750,15 +750,18 @@ virCgroupV2GetBlkioDeviceWeight(virCgroupPtr group,
                                 unsigned int *weight)
 {
     VIR_AUTOFREE(char *) str = NULL;
+    VIR_AUTOFREE(char *) value = NULL;
 
-    if (virCgroupGetValueForBlkDev(group,
-                                   VIR_CGROUP_CONTROLLER_BLKIO,
-                                   "io.weight",
-                                   path,
-                                   &str) < 0) {
+    if (virCgroupGetValueStr(group,
+                             VIR_CGROUP_CONTROLLER_BLKIO,
+                             "io.weight",
+                             &value) < 0) {
         return -1;
     }
 
+    if (virCgroupGetValueForBlkDev(value, path, &str) < 0)
+        return -1;
+
     if (!str) {
         *weight = 0;
     } else if (virStrToLong_ui(str, NULL, 10, weight) < 0) {
@@ -804,17 +807,20 @@ virCgroupV2GetBlkioDeviceReadIops(virCgroupPtr group,
                                   unsigned int *riops)
 {
     VIR_AUTOFREE(char *) str = NULL;
+    VIR_AUTOFREE(char *) value = NULL;
     const char *name = "riops=";
     char *tmp;
 
-    if (virCgroupGetValueForBlkDev(group,
-                                   VIR_CGROUP_CONTROLLER_BLKIO,
-                                   "io.max",
-                                   path,
-                                   &str) < 0) {
+    if (virCgroupGetValueStr(group,
+                             VIR_CGROUP_CONTROLLER_BLKIO,
+                             "io.max",
+                             &value) < 0) {
         return -1;
     }
 
+    if (virCgroupGetValueForBlkDev(value, path, &str) < 0)
+        return -1;
+
     if (!str) {
         *riops = 0;
     } else {
@@ -872,17 +878,20 @@ virCgroupV2GetBlkioDeviceWriteIops(virCgroupPtr group,
                                    unsigned int *wiops)
 {
     VIR_AUTOFREE(char *) str = NULL;
+    VIR_AUTOFREE(char *) value = NULL;
     const char *name = "wiops=";
     char *tmp;
 
-    if (virCgroupGetValueForBlkDev(group,
-                                   VIR_CGROUP_CONTROLLER_BLKIO,
-                                   "io.max",
-                                   path,
-                                   &str) < 0) {
+    if (virCgroupGetValueStr(group,
+                             VIR_CGROUP_CONTROLLER_BLKIO,
+                             "io.max",
+                             &value) < 0) {
         return -1;
     }
 
+    if (virCgroupGetValueForBlkDev(value, path, &str) < 0)
+        return -1;
+
     if (!str) {
         *wiops = 0;
     } else {
@@ -940,17 +949,20 @@ virCgroupV2GetBlkioDeviceReadBps(virCgroupPtr group,
                                  unsigned long long *rbps)
 {
     VIR_AUTOFREE(char *) str = NULL;
+    VIR_AUTOFREE(char *) value = NULL;
     const char *name = "rbps=";
     char *tmp;
 
-    if (virCgroupGetValueForBlkDev(group,
-                                   VIR_CGROUP_CONTROLLER_BLKIO,
-                                   "io.max",
-                                   path,
-                                   &str) < 0) {
+    if (virCgroupGetValueStr(group,
+                             VIR_CGROUP_CONTROLLER_BLKIO,
+                             "io.max",
+                             &value) < 0) {
         return -1;
     }
 
+    if (virCgroupGetValueForBlkDev(value, path, &str) < 0)
+        return -1;
+
     if (!str) {
         *rbps = 0;
     } else {
@@ -1008,17 +1020,20 @@ virCgroupV2GetBlkioDeviceWriteBps(virCgroupPtr group,
                                   unsigned long long *wbps)
 {
     VIR_AUTOFREE(char *) str = NULL;
+    VIR_AUTOFREE(char *) value = NULL;
     const char *name = "wbps=";
     char *tmp;
 
-    if (virCgroupGetValueForBlkDev(group,
-                                   VIR_CGROUP_CONTROLLER_BLKIO,
-                                   "io.max",
-                                   path,
-                                   &str) < 0) {
+    if (virCgroupGetValueStr(group,
+                             VIR_CGROUP_CONTROLLER_BLKIO,
+                             "io.max",
+                             &value) < 0) {
         return -1;
     }
 
+    if (virCgroupGetValueForBlkDev(value, path, &str) < 0)
+        return -1;
+
     if (!str) {
         *wbps = 0;
     } else {