[libvirt] [PATCHv2 01/10] util: add Intel x86 RDT/CMT support
Wang Huaqiang
huaqiang.wang at intel.com
Mon Jul 9 07:00:49 UTC 2018
Add RDT/CMT feature (Intel x86) by interacting with kernel
resctrl file system. Integrate code into util/resctrl.
---
src/libvirt_private.syms | 10 ++
src/util/virresctrl.c | 338 +++++++++++++++++++++++++++++++++++++++++++++++
src/util/virresctrl.h | 40 ++++++
3 files changed, 388 insertions(+)
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index 3e30490..b10a3a5 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -2655,6 +2655,16 @@ virResctrlAllocSetID;
virResctrlAllocSetSize;
virResctrlInfoGetCache;
virResctrlInfoNew;
+virResctrlMonAddPID;
+virResctrlMonCreate;
+virResctrlMonDeterminePath;
+virResctrlMonGetAlloc;
+virResctrlMonGetCacheOccupancy;
+virResctrlMonGetID;
+virResctrlMonIsRunning;
+virResctrlMonNew;
+virResctrlMonRemove;
+virResctrlMonSetID;
# util/virrotatingfile.h
diff --git a/src/util/virresctrl.c b/src/util/virresctrl.c
index e492a63..3dca937 100644
--- a/src/util/virresctrl.c
+++ b/src/util/virresctrl.c
@@ -90,6 +90,7 @@ typedef virResctrlAllocPerLevel *virResctrlAllocPerLevelPtr;
/* Class definitions and initializations */
static virClassPtr virResctrlInfoClass;
static virClassPtr virResctrlAllocClass;
+static virClassPtr virResctrlMonClass;
/* virResctrlInfo */
@@ -257,6 +258,33 @@ virResctrlAllocDispose(void *obj)
}
+
+/* virResctrlMon*/
+struct _virResctrlMon {
+ virObject parent;
+
+ /* alloc: keeps the pointer to a allocation group if sharing same
+ * resctrlfs subdirectory with a allocation group.
+ * NULL for a standalone monitoring group.*/
+ virResctrlAllocPtr alloc;
+ /* The identifier (any unique string for now) */
+ char *id;
+ /* libvirt-generated path, be identical to path of 'alloc' if sharing
+ * same resctrlfs subdirectory with allocation group */
+ char *path;
+};
+
+
+static void
+virResctrlMonDispose(void *obj)
+{
+ virResctrlMonPtr resctrlMon = obj;
+
+ VIR_FREE(resctrlMon->id);
+ VIR_FREE(resctrlMon->path);
+}
+
+
/* Global initialization for classes */
static int
virResctrlOnceInit(void)
@@ -267,6 +295,9 @@ virResctrlOnceInit(void)
if (!VIR_CLASS_NEW(virResctrlAlloc, virClassForObject()))
return -1;
+ if (!VIR_CLASS_NEW(virResctrlMon, virClassForObject()))
+ return -1;
+
return 0;
}
@@ -1612,3 +1643,310 @@ virResctrlAllocRemove(virResctrlAllocPtr alloc)
return ret;
}
+
+
+virResctrlMonPtr
+virResctrlMonNew(void)
+{
+ if (virResctrlInitialize() < 0)
+ return NULL;
+
+ return virObjectNew(virResctrlMonClass);
+}
+
+
+int
+virResctrlMonSetID(virResctrlMonPtr mon,
+ const char *id)
+{
+ if (!id) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Resctrl mon group 'id' cannot be NULL"));
+ return -1;
+ }
+
+ return VIR_STRDUP(mon->id, id);
+}
+
+
+const char *
+virResctrlMonGetID(virResctrlMonPtr mon)
+{
+ return mon->id;
+}
+
+
+int
+virResctrlMonDeterminePath(virResctrlMonPtr mon,
+ const char *machinename)
+{
+ char *grouppath = NULL;
+ int ret = -1;
+
+ if (!mon->id) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Resctrl mon group id must be set before creation"));
+ goto cleanup;
+ }
+
+ if (!mon->path) {
+ if (virAsprintf(&grouppath, "%s/mon_groups/%s-%s",
+ SYSFS_RESCTRL_PATH, machinename, mon->id) < 0) {
+
+ goto cleanup;
+ }
+ VIR_STEAL_PTR(mon->path, grouppath);
+
+ } else {
+ /* if path exists, validate it */
+ if (virAsprintf(&grouppath, "%s/%s-%s",
+ SYSFS_RESCTRL_PATH, machinename, mon->id) < 0) {
+ goto cleanup;
+ }
+
+ if (STRNEQ(mon->path, grouppath))
+ goto cleanup;
+ }
+
+ ret = 0;
+ cleanup:
+ VIR_FREE(grouppath);
+ return ret;
+}
+
+
+int
+virResctrlMonAddPID(virResctrlMonPtr mon,
+ pid_t pid)
+{
+ char *tasks = NULL;
+ char *pidstr = NULL;
+ int ret = 0;
+
+ /* PID only writes to standalone mon group */
+ if (mon->alloc)
+ return 0;
+
+ if (!mon->path) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Cannot add pid to non-existing resctrl mon group"));
+ return -1;
+ }
+
+ VIR_DEBUG("Add PID %d to domain %s\n",
+ pid, mon->path);
+
+ if (virAsprintf(&tasks, "%s/tasks", mon->path) < 0)
+ return -1;
+
+ if (virAsprintf(&pidstr, "%lld", (long long int) pid) < 0)
+ goto cleanup;
+
+ if (virFileWriteStr(tasks, pidstr, 0) < 0) {
+ virReportSystemError(errno,
+ _("Cannot write pid in tasks file '%s'"),
+ tasks);
+ goto cleanup;
+ }
+
+ ret = 0;
+ cleanup:
+ VIR_FREE(tasks);
+ VIR_FREE(pidstr);
+ return ret;
+}
+
+
+int
+virResctrlMonCreate(virResctrlAllocPtr alloc,
+ virResctrlMonPtr mon,
+ const char *machinename)
+{
+ int ret = -1;
+ int lockfd = -1;
+
+ if (!mon)
+ return -1;
+
+ if (alloc) {
+ if (!virFileExists(alloc->path)) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("resctrl mon group: allocation group exists but not "
+ "valid"));
+ return -1;
+ }
+ mon->alloc = alloc;
+
+ if (virResctrlMonDeterminePath(mon, machinename) < 0)
+ return -1;
+ } else {
+ if (virResctrlMonDeterminePath(mon, machinename) < 0)
+ return -1;
+
+ lockfd = virResctrlLockWrite();
+ if (lockfd < 0)
+ goto cleanup;
+
+ if (virFileExists(mon->path)) {
+ VIR_DEBUG("Removing resctrl mon group %s", mon->path);
+ if (rmdir(mon->path) != 0 && errno != ENOENT) {
+ virReportSystemError(errno,
+ _("Unable to remove resctrl directory '%s'"),
+ mon->path);
+ goto cleanup;
+ }
+ }
+
+ if (virFileMakePath(mon->path) < 0) {
+ virReportSystemError(errno,
+ _("Cannot create resctrl directory '%s'"),
+ mon->path);
+ goto cleanup;
+ }
+ }
+
+ ret = 0;
+ cleanup:
+ virResctrlUnlock(lockfd);
+ return ret;
+}
+
+
+int
+virResctrlMonRemove(virResctrlMonPtr mon)
+{
+ int ret = 0;
+
+ if (!mon->path)
+ return 0;
+
+ VIR_DEBUG("Removing resctrl mon group %s", mon->path);
+ if (rmdir(mon->path) != 0 && errno != ENOENT) {
+ ret = -errno;
+ VIR_ERROR(_("Unable to remove %s (%d)"), mon->path, errno);
+ }
+
+ return ret;
+}
+
+
+bool
+virResctrlMonIsRunning(virResctrlMonPtr mon)
+{
+ bool ret = false;
+ int rv = -1;
+ char *tasks = NULL;
+
+ if (mon && virFileExists(mon->path)) {
+ rv = virFileReadValueString(&tasks, "%s/tasks", mon->path);
+ if (rv < 0)
+ goto cleanup;
+
+ if (!tasks || !tasks[0])
+ goto cleanup;
+
+ ret = true;
+ }
+
+ cleanup:
+ VIR_FREE(tasks);
+ return ret;
+}
+
+
+static int
+virResctrlMonGetStatistic(virResctrlMonPtr mon,
+ const char *resfile,
+ unsigned int *value)
+{
+ DIR *dirp = NULL;
+ int ret = -1;
+ int rv = -1;
+ struct dirent *ent = NULL;
+ unsigned int val = 0;
+ unsigned int valtotal = 0;
+ virBuffer buf = VIR_BUFFER_INITIALIZER;
+ char *mondatapath = NULL;
+
+ if (!mon->path)
+ goto cleanup;
+
+ if (!resfile)
+ goto cleanup;
+
+ *value = 0;
+
+ rv = virDirOpenIfExists(&dirp, mon->path);
+ if (rv <= 0)
+ goto cleanup;
+
+ virBufferAsprintf(&buf, "%s/mon_data",
+ mon->path);
+ mondatapath = virBufferContentAndReset(&buf);
+ if (!mondatapath)
+ goto cleanup;
+
+ VIR_DEBUG("Seek llc_occupancy file from root: %s ",
+ mondatapath);
+
+ if (virDirOpen(&dirp, mondatapath) < 0)
+ goto cleanup;
+
+ while ((rv = virDirRead(dirp, &ent, mondatapath)) > 0) {
+ VIR_DEBUG("Parsing file '%s'", ent->d_name);
+ if (ent->d_type != DT_DIR)
+ continue;
+
+ if (STRNEQLEN(ent->d_name, "mon_L", 5))
+ continue;
+
+ rv = virFileReadValueUint(&val,
+ "%s/%s/%s",
+ mondatapath, ent->d_name, resfile);
+
+ if (rv == -2) {
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ _("file %s/%s/%s does not exist"),
+ mondatapath, ent->d_name, resfile);
+ goto cleanup;
+ } else {
+ if (rv < 0)
+ goto cleanup;
+ }
+
+ valtotal += val;
+ }
+
+ *value = valtotal;
+ ret = 0;
+ cleanup:
+ VIR_FREE(mondatapath);
+ VIR_DIR_CLOSE(dirp);
+ return ret;
+}
+
+int
+virResctrlMonGetCacheOccupancy(virResctrlMonPtr mon,
+ unsigned int * cacheoccu)
+{
+ const char *cacheoccufile = "llc_occupancy";
+ unsigned int value = 0;
+ int ret = - 1;
+
+ *cacheoccu = 0;
+
+ ret = virResctrlMonGetStatistic(mon,
+ cacheoccufile,
+ &value);
+ if (ret >= 0)
+ *cacheoccu = value;
+
+ return ret;
+}
+
+
+virResctrlAllocPtr
+virResctrlMonGetAlloc(virResctrlMonPtr mon)
+{
+ return mon->alloc;
+}
diff --git a/src/util/virresctrl.h b/src/util/virresctrl.h
index 9052a2b..6865ab6 100644
--- a/src/util/virresctrl.h
+++ b/src/util/virresctrl.h
@@ -116,4 +116,44 @@ virResctrlAllocAddPID(virResctrlAllocPtr alloc,
int
virResctrlAllocRemove(virResctrlAllocPtr alloc);
+
+/* Monitoring-related things */
+typedef struct _virResctrlMon virResctrlMon;
+typedef virResctrlMon *virResctrlMonPtr;
+
+virResctrlMonPtr
+virResctrlMonNew(void);
+
+int
+virResctrlMonSetID(virResctrlMonPtr mon,
+ const char *id);
+
+const char *
+virResctrlMonGetID(virResctrlMonPtr mon);
+
+int
+virResctrlMonDeterminePath(virResctrlMonPtr mon,
+ const char *machinename);
+
+int
+virResctrlMonAddPID(virResctrlMonPtr alloc,
+ pid_t pid);
+
+int
+virResctrlMonCreate(virResctrlAllocPtr pairedalloc,
+ virResctrlMonPtr mon,
+ const char *machinename);
+
+int
+virResctrlMonRemove(virResctrlMonPtr mon);
+
+bool
+virResctrlMonIsRunning(virResctrlMonPtr mon);
+
+int
+virResctrlMonGetCacheOccupancy(virResctrlMonPtr mon,
+ unsigned int * cacheoccu);
+
+virResctrlAllocPtr
+virResctrlMonGetAlloc(virResctrlMonPtr mon);
#endif /* __VIR_RESCTRL_H__ */
--
2.7.4
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