Merge pull request #3905 from htejun/cgroup-v2-cpu

core: add cgroup CPU controller support on the unified hierarchy

(zj: merging not squashing to make it clear against which upstream this patch was developed.)

8 files changed, 252 insertions, 44 deletions

diff --git a/src/core/cgroup.c b/src/core/cgroup.c
index c19e43f571..910a64b4da 100644
--- a/src/core/cgroup.c
+++ b/src/core/cgroup.c
@@ -57,9 +57,12 @@ void cgroup_context_init(CGroupContext *c) {
         /* Initialize everything to the kernel defaults, assuming the
          * structure is preinitialized to 0 */
 
+        c->cpu_weight = CGROUP_WEIGHT_INVALID;
+        c->startup_cpu_weight = CGROUP_WEIGHT_INVALID;
+        c->cpu_quota_per_sec_usec = USEC_INFINITY;
+
         c->cpu_shares = CGROUP_CPU_SHARES_INVALID;
         c->startup_cpu_shares = CGROUP_CPU_SHARES_INVALID;
-        c->cpu_quota_per_sec_usec = USEC_INFINITY;
 
         c->memory_high = CGROUP_LIMIT_MAX;
         c->memory_max = CGROUP_LIMIT_MAX;
@@ -158,6 +161,8 @@ void cgroup_context_dump(CGroupContext *c, FILE* f, const char *prefix) {
                 "%sBlockIOAccounting=%s\n"
                 "%sMemoryAccounting=%s\n"
                 "%sTasksAccounting=%s\n"
+                "%sCPUWeight=%" PRIu64 "\n"
+                "%sStartupCPUWeight=%" PRIu64 "\n"
                 "%sCPUShares=%" PRIu64 "\n"
                 "%sStartupCPUShares=%" PRIu64 "\n"
                 "%sCPUQuotaPerSecSec=%s\n"
@@ -177,6 +182,8 @@ void cgroup_context_dump(CGroupContext *c, FILE* f, const char *prefix) {
                 prefix, yes_no(c->blockio_accounting),
                 prefix, yes_no(c->memory_accounting),
                 prefix, yes_no(c->tasks_accounting),
+                prefix, c->cpu_weight,
+                prefix, c->startup_cpu_weight,
                 prefix, c->cpu_shares,
                 prefix, c->startup_cpu_shares,
                 prefix, format_timespan(u, sizeof(u), c->cpu_quota_per_sec_usec, 1),
@@ -382,6 +389,95 @@ fail:
         return -errno;
 }
 
+static bool cgroup_context_has_cpu_weight(CGroupContext *c) {
+        return c->cpu_weight != CGROUP_WEIGHT_INVALID ||
+                c->startup_cpu_weight != CGROUP_WEIGHT_INVALID;
+}
+
+static bool cgroup_context_has_cpu_shares(CGroupContext *c) {
+        return c->cpu_shares != CGROUP_CPU_SHARES_INVALID ||
+                c->startup_cpu_shares != CGROUP_CPU_SHARES_INVALID;
+}
+
+static uint64_t cgroup_context_cpu_weight(CGroupContext *c, ManagerState state) {
+        if (IN_SET(state, MANAGER_STARTING, MANAGER_INITIALIZING) &&
+            c->startup_cpu_weight != CGROUP_WEIGHT_INVALID)
+                return c->startup_cpu_weight;
+        else if (c->cpu_weight != CGROUP_WEIGHT_INVALID)
+                return c->cpu_weight;
+        else
+                return CGROUP_WEIGHT_DEFAULT;
+}
+
+static uint64_t cgroup_context_cpu_shares(CGroupContext *c, ManagerState state) {
+        if (IN_SET(state, MANAGER_STARTING, MANAGER_INITIALIZING) &&
+            c->startup_cpu_shares != CGROUP_CPU_SHARES_INVALID)
+                return c->startup_cpu_shares;
+        else if (c->cpu_shares != CGROUP_CPU_SHARES_INVALID)
+                return c->cpu_shares;
+        else
+                return CGROUP_CPU_SHARES_DEFAULT;
+}
+
+static void cgroup_apply_unified_cpu_config(Unit *u, uint64_t weight, uint64_t quota) {
+        char buf[MAX(DECIMAL_STR_MAX(uint64_t) + 1, (DECIMAL_STR_MAX(usec_t) + 1) * 2)];
+        int r;
+
+        xsprintf(buf, "%" PRIu64 "\n", weight);
+        r = cg_set_attribute("cpu", u->cgroup_path, "cpu.weight", buf);
+        if (r < 0)
+                log_unit_full(u, IN_SET(r, -ENOENT, -EROFS, -EACCES) ? LOG_DEBUG : LOG_WARNING, r,
+                              "Failed to set cpu.weight: %m");
+
+        if (quota != USEC_INFINITY)
+                xsprintf(buf, USEC_FMT " " USEC_FMT "\n",
+                         quota * CGROUP_CPU_QUOTA_PERIOD_USEC / USEC_PER_SEC, CGROUP_CPU_QUOTA_PERIOD_USEC);
+        else
+                xsprintf(buf, "max " USEC_FMT "\n", CGROUP_CPU_QUOTA_PERIOD_USEC);
+
+        r = cg_set_attribute("cpu", u->cgroup_path, "cpu.max", buf);
+
+        if (r < 0)
+                log_unit_full(u, IN_SET(r, -ENOENT, -EROFS, -EACCES) ? LOG_DEBUG : LOG_WARNING, r,
+                              "Failed to set cpu.max: %m");
+}
+
+static void cgroup_apply_legacy_cpu_config(Unit *u, uint64_t shares, uint64_t quota) {
+        char buf[MAX(DECIMAL_STR_MAX(uint64_t), DECIMAL_STR_MAX(usec_t)) + 1];
+        int r;
+
+        xsprintf(buf, "%" PRIu64 "\n", shares);
+        r = cg_set_attribute("cpu", u->cgroup_path, "cpu.shares", buf);
+        if (r < 0)
+                log_unit_full(u, IN_SET(r, -ENOENT, -EROFS, -EACCES) ? LOG_DEBUG : LOG_WARNING, r,
+                              "Failed to set cpu.shares: %m");
+
+        xsprintf(buf, USEC_FMT "\n", CGROUP_CPU_QUOTA_PERIOD_USEC);
+        r = cg_set_attribute("cpu", u->cgroup_path, "cpu.cfs_period_us", buf);
+        if (r < 0)
+                log_unit_full(u, IN_SET(r, -ENOENT, -EROFS, -EACCES) ? LOG_DEBUG : LOG_WARNING, r,
+                              "Failed to set cpu.cfs_period_us: %m");
+
+        if (quota != USEC_INFINITY) {
+                xsprintf(buf, USEC_FMT "\n", quota * CGROUP_CPU_QUOTA_PERIOD_USEC / USEC_PER_SEC);
+                r = cg_set_attribute("cpu", u->cgroup_path, "cpu.cfs_quota_us", buf);
+        } else
+                r = cg_set_attribute("cpu", u->cgroup_path, "cpu.cfs_quota_us", "-1");
+        if (r < 0)
+                log_unit_full(u, IN_SET(r, -ENOENT, -EROFS, -EACCES) ? LOG_DEBUG : LOG_WARNING, r,
+                              "Failed to set cpu.cfs_quota_us: %m");
+}
+
+static uint64_t cgroup_cpu_shares_to_weight(uint64_t shares) {
+        return CLAMP(shares * CGROUP_WEIGHT_DEFAULT / CGROUP_CPU_SHARES_DEFAULT,
+                     CGROUP_WEIGHT_MIN, CGROUP_WEIGHT_MAX);
+}
+
+static uint64_t cgroup_cpu_weight_to_shares(uint64_t weight) {
+        return CLAMP(weight * CGROUP_CPU_SHARES_DEFAULT / CGROUP_WEIGHT_DEFAULT,
+                     CGROUP_CPU_SHARES_MIN, CGROUP_CPU_SHARES_MAX);
+}
+
 static bool cgroup_context_has_io_config(CGroupContext *c) {
         return c->io_accounting ||
                 c->io_weight != CGROUP_WEIGHT_INVALID ||
@@ -566,30 +662,42 @@ static void cgroup_context_apply(Unit *u, CGroupMask mask, ManagerState state) {
          * and missing cgroups, i.e. EROFS and ENOENT. */
 
         if ((mask & CGROUP_MASK_CPU) && !is_root) {
-                char buf[MAX(DECIMAL_STR_MAX(uint64_t), DECIMAL_STR_MAX(usec_t)) + 1];
+                bool has_weight = cgroup_context_has_cpu_weight(c);
+                bool has_shares = cgroup_context_has_cpu_shares(c);
 
-                sprintf(buf, "%" PRIu64 "\n",
-                        IN_SET(state, MANAGER_STARTING, MANAGER_INITIALIZING) && c->startup_cpu_shares != CGROUP_CPU_SHARES_INVALID ? c->startup_cpu_shares :
-                        c->cpu_shares != CGROUP_CPU_SHARES_INVALID ? c->cpu_shares : CGROUP_CPU_SHARES_DEFAULT);
-                r = cg_set_attribute("cpu", path, "cpu.shares", buf);
-                if (r < 0)
-                        log_unit_full(u, IN_SET(r, -ENOENT, -EROFS, -EACCES) ? LOG_DEBUG : LOG_WARNING, r,
-                                      "Failed to set cpu.shares: %m");
+                if (cg_unified() > 0) {
+                        uint64_t weight;
 
-                sprintf(buf, USEC_FMT "\n", CGROUP_CPU_QUOTA_PERIOD_USEC);
-                r = cg_set_attribute("cpu", path, "cpu.cfs_period_us", buf);
-                if (r < 0)
-                        log_unit_full(u, IN_SET(r, -ENOENT, -EROFS, -EACCES) ? LOG_DEBUG : LOG_WARNING, r,
-                                      "Failed to set cpu.cfs_period_us: %m");
+                        if (has_weight)
+                                weight = cgroup_context_cpu_weight(c, state);
+                        else if (has_shares) {
+                                uint64_t shares = cgroup_context_cpu_shares(c, state);
 
-                if (c->cpu_quota_per_sec_usec != USEC_INFINITY) {
-                        sprintf(buf, USEC_FMT "\n", c->cpu_quota_per_sec_usec * CGROUP_CPU_QUOTA_PERIOD_USEC / USEC_PER_SEC);
-                        r = cg_set_attribute("cpu", path, "cpu.cfs_quota_us", buf);
-                } else
-                        r = cg_set_attribute("cpu", path, "cpu.cfs_quota_us", "-1");
-                if (r < 0)
-                        log_unit_full(u, IN_SET(r, -ENOENT, -EROFS, -EACCES) ? LOG_DEBUG : LOG_WARNING, r,
-                                      "Failed to set cpu.cfs_quota_us: %m");
+                                weight = cgroup_cpu_shares_to_weight(shares);
+
+                                log_cgroup_compat(u, "Applying [Startup]CpuShares %" PRIu64 " as [Startup]CpuWeight %" PRIu64 " on %s",
+                                                  shares, weight, path);
+                        } else
+                                weight = CGROUP_WEIGHT_DEFAULT;
+
+                        cgroup_apply_unified_cpu_config(u, weight, c->cpu_quota_per_sec_usec);
+                } else {
+                        uint64_t shares;
+
+                        if (has_shares)
+                                shares = cgroup_context_cpu_shares(c, state);
+                        else if (has_weight) {
+                                uint64_t weight = cgroup_context_cpu_weight(c, state);
+
+                                shares = cgroup_cpu_weight_to_shares(weight);
+
+                                log_cgroup_compat(u, "Applying [Startup]CpuWeight %" PRIu64 " as [Startup]CpuShares %" PRIu64 " on %s",
+                                                  weight, shares, path);
+                        } else
+                                shares = CGROUP_CPU_SHARES_DEFAULT;
+
+                        cgroup_apply_legacy_cpu_config(u, shares, c->cpu_quota_per_sec_usec);
+                }
         }
 
         if (mask & CGROUP_MASK_IO) {
@@ -864,8 +972,8 @@ CGroupMask cgroup_context_get_mask(CGroupContext *c) {
         /* Figure out which controllers we need */
 
         if (c->cpu_accounting ||
-            c->cpu_shares != CGROUP_CPU_SHARES_INVALID ||
-            c->startup_cpu_shares != CGROUP_CPU_SHARES_INVALID ||
+            cgroup_context_has_cpu_weight(c) ||
+            cgroup_context_has_cpu_shares(c) ||
             c->cpu_quota_per_sec_usec != USEC_INFINITY)
                 mask |= CGROUP_MASK_CPUACCT | CGROUP_MASK_CPU;
 
@@ -1890,18 +1998,37 @@ static int unit_get_cpu_usage_raw(Unit *u, nsec_t *ret) {
         if (!u->cgroup_path)
                 return -ENODATA;
 
-        if ((u->cgroup_realized_mask & CGROUP_MASK_CPUACCT) == 0)
-                return -ENODATA;
+        if (cg_unified() > 0) {
+                const char *keys[] = { "usage_usec", NULL };
+                _cleanup_free_ char *val = NULL;
+                uint64_t us;
 
-        r = cg_get_attribute("cpuacct", u->cgroup_path, "cpuacct.usage", &v);
-        if (r == -ENOENT)
-                return -ENODATA;
-        if (r < 0)
-                return r;
+                if ((u->cgroup_realized_mask & CGROUP_MASK_CPU) == 0)
+                        return -ENODATA;
 
-        r = safe_atou64(v, &ns);
-        if (r < 0)
-                return r;
+                r = cg_get_keyed_attribute("cpu", u->cgroup_path, "cpu.stat", keys, &val);
+                if (r < 0)
+                        return r;
+
+                r = safe_atou64(val, &us);
+                if (r < 0)
+                        return r;
+
+                ns = us * NSEC_PER_USEC;
+        } else {
+                if ((u->cgroup_realized_mask & CGROUP_MASK_CPUACCT) == 0)
+                        return -ENODATA;
+
+                r = cg_get_attribute("cpuacct", u->cgroup_path, "cpuacct.usage", &v);
+                if (r == -ENOENT)
+                        return -ENODATA;
+                if (r < 0)
+                        return r;
+
+                r = safe_atou64(v, &ns);
+                if (r < 0)
+                        return r;
+        }
 
         *ret = ns;
         return 0;
@@ -1915,8 +2042,8 @@ int unit_get_cpu_usage(Unit *u, nsec_t *ret) {
         if (r < 0)
                 return r;
 
-        if (ns > u->cpuacct_usage_base)
-                ns -= u->cpuacct_usage_base;
+        if (ns > u->cpu_usage_base)
+                ns -= u->cpu_usage_base;
         else
                 ns = 0;
 
@@ -1932,11 +2059,11 @@ int unit_reset_cpu_usage(Unit *u) {
 
         r = unit_get_cpu_usage_raw(u, &ns);
         if (r < 0) {
-                u->cpuacct_usage_base = 0;
+                u->cpu_usage_base = 0;
                 return r;
         }
 
-        u->cpuacct_usage_base = ns;
+        u->cpu_usage_base = ns;
         return 0;
 }
 
diff --git a/src/core/cgroup.h b/src/core/cgroup.h
index a57403e79f..2fe9cc4039 100644
--- a/src/core/cgroup.h
+++ b/src/core/cgroup.h
@@ -89,6 +89,10 @@ struct CGroupContext {
         bool tasks_accounting;
 
         /* For unified hierarchy */
+        uint64_t cpu_weight;
+        uint64_t startup_cpu_weight;
+        usec_t cpu_quota_per_sec_usec;
+
         uint64_t io_weight;
         uint64_t startup_io_weight;
         LIST_HEAD(CGroupIODeviceWeight, io_device_weights);
@@ -101,7 +105,6 @@ struct CGroupContext {
         /* For legacy hierarchies */
         uint64_t cpu_shares;
         uint64_t startup_cpu_shares;
-        usec_t cpu_quota_per_sec_usec;
 
         uint64_t blockio_weight;
         uint64_t startup_blockio_weight;
diff --git a/src/core/dbus-cgroup.c b/src/core/dbus-cgroup.c
index 85b0c86a2f..2ca80d2996 100644
--- a/src/core/dbus-cgroup.c
+++ b/src/core/dbus-cgroup.c
@@ -210,6 +210,8 @@ const sd_bus_vtable bus_cgroup_vtable[] = {
         SD_BUS_VTABLE_START(0),
         SD_BUS_PROPERTY("Delegate", "b", bus_property_get_bool, offsetof(CGroupContext, delegate), 0),
         SD_BUS_PROPERTY("CPUAccounting", "b", bus_property_get_bool, offsetof(CGroupContext, cpu_accounting), 0),
+        SD_BUS_PROPERTY("CPUWeight", "t", NULL, offsetof(CGroupContext, cpu_weight), 0),
+        SD_BUS_PROPERTY("StartupCPUWeight", "t", NULL, offsetof(CGroupContext, startup_cpu_weight), 0),
         SD_BUS_PROPERTY("CPUShares", "t", NULL, offsetof(CGroupContext, cpu_shares), 0),
         SD_BUS_PROPERTY("StartupCPUShares", "t", NULL, offsetof(CGroupContext, startup_cpu_shares), 0),
         SD_BUS_PROPERTY("CPUQuotaPerSecUSec", "t", bus_property_get_usec, offsetof(CGroupContext, cpu_quota_per_sec_usec), 0),
@@ -303,6 +305,50 @@ int bus_cgroup_set_property(
 
                 return 1;
 
+        } else if (streq(name, "CPUWeight")) {
+                uint64_t weight;
+
+                r = sd_bus_message_read(message, "t", &weight);
+                if (r < 0)
+                        return r;
+
+                if (!CGROUP_WEIGHT_IS_OK(weight))
+                        return sd_bus_error_set_errnof(error, EINVAL, "CPUWeight value out of range");
+
+                if (mode != UNIT_CHECK) {
+                        c->cpu_weight = weight;
+                        unit_invalidate_cgroup(u, CGROUP_MASK_CPU);
+
+                        if (weight == CGROUP_WEIGHT_INVALID)
+                                unit_write_drop_in_private(u, mode, name, "CPUWeight=");
+                        else
+                                unit_write_drop_in_private_format(u, mode, name, "CPUWeight=%" PRIu64, weight);
+                }
+
+                return 1;
+
+        } else if (streq(name, "StartupCPUWeight")) {
+                uint64_t weight;
+
+                r = sd_bus_message_read(message, "t", &weight);
+                if (r < 0)
+                        return r;
+
+                if (!CGROUP_WEIGHT_IS_OK(weight))
+                        return sd_bus_error_set_errnof(error, EINVAL, "StartupCPUWeight value out of range");
+
+                if (mode != UNIT_CHECK) {
+                        c->startup_cpu_weight = weight;
+                        unit_invalidate_cgroup(u, CGROUP_MASK_CPU);
+
+                        if (weight == CGROUP_CPU_SHARES_INVALID)
+                                unit_write_drop_in_private(u, mode, name, "StartupCPUWeight=");
+                        else
+                                unit_write_drop_in_private_format(u, mode, name, "StartupCPUWeight=%" PRIu64, weight);
+                }
+
+                return 1;
+
         } else if (streq(name, "CPUShares")) {
                 uint64_t shares;
 
diff --git a/src/core/load-fragment-gperf.gperf.m4 b/src/core/load-fragment-gperf.gperf.m4
index 251155b428..05fe0df7e3 100644
--- a/src/core/load-fragment-gperf.gperf.m4
+++ b/src/core/load-fragment-gperf.gperf.m4
@@ -122,6 +122,8 @@ $1.KillSignal,                   config_parse_signal,                0,
 m4_define(`CGROUP_CONTEXT_CONFIG_ITEMS',
 `$1.Slice,                       config_parse_unit_slice,            0,                             0
 $1.CPUAccounting,                config_parse_bool,                  0,                             offsetof($1, cgroup_context.cpu_accounting)
+$1.CPUWeight,                    config_parse_cpu_weight,            0,                             offsetof($1, cgroup_context.cpu_weight)
+$1.StartupCPUWeight,             config_parse_cpu_weight,            0,                             offsetof($1, cgroup_context.startup_cpu_weight)
 $1.CPUShares,                    config_parse_cpu_shares,            0,                             offsetof($1, cgroup_context.cpu_shares)
 $1.StartupCPUShares,             config_parse_cpu_shares,            0,                             offsetof($1, cgroup_context.startup_cpu_shares)
 $1.CPUQuota,                     config_parse_cpu_quota,             0,                             offsetof($1, cgroup_context)
diff --git a/src/core/load-fragment.c b/src/core/load-fragment.c
index 420f368689..4ad6c4d79b 100644
--- a/src/core/load-fragment.c
+++ b/src/core/load-fragment.c
@@ -2851,6 +2851,34 @@ int config_parse_unit_slice(
 
 DEFINE_CONFIG_PARSE_ENUM(config_parse_device_policy, cgroup_device_policy, CGroupDevicePolicy, "Failed to parse device policy");
 
+int config_parse_cpu_weight(
+                const char *unit,
+                const char *filename,
+                unsigned line,
+                const char *section,
+                unsigned section_line,
+                const char *lvalue,
+                int ltype,
+                const char *rvalue,
+                void *data,
+                void *userdata) {
+
+        uint64_t *weight = data;
+        int r;
+
+        assert(filename);
+        assert(lvalue);
+        assert(rvalue);
+
+        r = cg_weight_parse(rvalue, weight);
+        if (r < 0) {
+                log_syntax(unit, LOG_ERR, filename, line, r, "CPU weight '%s' invalid. Ignoring.", rvalue);
+                return 0;
+        }
+
+        return 0;
+}
+
 int config_parse_cpu_shares(
                 const char *unit,
                 const char *filename,
@@ -4191,6 +4219,7 @@ void unit_dump_config_items(FILE *f) {
                 { config_parse_address_families,      "FAMILIES" },
 #endif
                 { config_parse_cpu_shares,            "SHARES" },
+                { config_parse_cpu_weight,            "WEIGHT" },
                 { config_parse_memory_limit,          "LIMIT" },
                 { config_parse_device_allow,          "DEVICE" },
                 { config_parse_device_policy,         "POLICY" },
diff --git a/src/core/load-fragment.h b/src/core/load-fragment.h
index 213bce55a7..8b688740cf 100644
--- a/src/core/load-fragment.h
+++ b/src/core/load-fragment.h
@@ -81,6 +81,7 @@ int config_parse_syscall_errno(const char *unit, const char *filename, unsigned
 int config_parse_environ(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 int config_parse_pass_environ(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 int config_parse_unit_slice(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
+int config_parse_cpu_weight(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 int config_parse_cpu_shares(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 int config_parse_memory_limit(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 int config_parse_tasks_max(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
diff --git a/src/core/unit.c b/src/core/unit.c
index ff7c562fba..952604e0db 100644
--- a/src/core/unit.c
+++ b/src/core/unit.c
@@ -2608,7 +2608,7 @@ int unit_serialize(Unit *u, FILE *f, FDSet *fds, bool serialize_jobs) {
                 unit_serialize_item(u, f, "assert-result", yes_no(u->assert_result));
 
         unit_serialize_item(u, f, "transient", yes_no(u->transient));
-        unit_serialize_item_format(u, f, "cpuacct-usage-base", "%" PRIu64, u->cpuacct_usage_base);
+        unit_serialize_item_format(u, f, "cpu-usage-base", "%" PRIu64, u->cpu_usage_base);
 
         if (u->cgroup_path)
                 unit_serialize_item(u, f, "cgroup", u->cgroup_path);
@@ -2824,9 +2824,9 @@ int unit_deserialize(Unit *u, FILE *f, FDSet *fds) {
 
                         continue;
 
-                } else if (streq(l, "cpuacct-usage-base")) {
+                } else if (streq(l, "cpu-usage-base") || streq(l, "cpuacct-usage-base")) {
 
-                        r = safe_atou64(v, &u->cpuacct_usage_base);
+                        r = safe_atou64(v, &u->cpu_usage_base);
                         if (r < 0)
                                 log_unit_debug(u, "Failed to parse CPU usage %s, ignoring.", v);
 
diff --git a/src/core/unit.h b/src/core/unit.h
index 47eb8d50a6..a6c69938dd 100644
--- a/src/core/unit.h
+++ b/src/core/unit.h
@@ -184,8 +184,8 @@ struct Unit {
         UnitFileState unit_file_state;
         int unit_file_preset;
 
-        /* Where the cpuacct.usage cgroup counter was at the time the unit was started */
-        nsec_t cpuacct_usage_base;
+        /* Where the cpu.stat or cpuacct.usage was at the time the unit was started */
+        nsec_t cpu_usage_base;
 
         /* Counterparts in the cgroup filesystem */
         char *cgroup_path;