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 -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list