Merge pull request #18659 from poettering/permyriadification

use scaling relative to UINT32_MAX instead of percentages/permyriads wherever we can

30 files changed, 562 insertions, 384 deletions

diff --git a/src/basic/limits-util.c b/src/basic/limits-util.c
index 259c311a67..9f8e26d46a 100644
--- a/src/basic/limits-util.c
+++ b/src/basic/limits-util.c
@@ -77,7 +77,13 @@ uint64_t physical_memory(void) {
 }
 
 uint64_t physical_memory_scale(uint64_t v, uint64_t max) {
-        uint64_t p, m, ps, r;
+        uint64_t p, m, ps;
+
+        /* Shortcut two special cases */
+        if (v == 0)
+                return 0;
+        if (v == max)
+                return physical_memory();
 
         assert(max > 0);
 
@@ -90,17 +96,16 @@ uint64_t physical_memory_scale(uint64_t v, uint64_t max) {
         p = physical_memory() / ps;
         assert(p > 0);
 
-        m = p * v;
-        if (m / p != v)
+        if (v > UINT64_MAX / p)
                 return UINT64_MAX;
 
+        m = p * v;
         m /= max;
 
-        r = m * ps;
-        if (r / ps != m)
+        if (m > UINT64_MAX / ps)
                 return UINT64_MAX;
 
-        return r;
+        return m * ps;
 }
 
 uint64_t system_tasks_max(void) {
@@ -138,6 +143,12 @@ uint64_t system_tasks_max(void) {
 uint64_t system_tasks_max_scale(uint64_t v, uint64_t max) {
         uint64_t t, m;
 
+        /* Shortcut two special cases */
+        if (v == 0)
+                return 0;
+        if (v == max)
+                return system_tasks_max();
+
         assert(max > 0);
 
         /* Multiply the system's task value by the fraction v/max. Hence, if max==100 this calculates percentages
@@ -146,9 +157,9 @@ uint64_t system_tasks_max_scale(uint64_t v, uint64_t max) {
         t = system_tasks_max();
         assert(t > 0);
 
-        m = t * v;
-        if (m / t != v) /* overflow? */
+        if (v > UINT64_MAX / t) /* overflow? */
                 return UINT64_MAX;
 
+        m = t * v;
         return m / max;
 }
diff --git a/src/basic/meson.build b/src/basic/meson.build
index 0b0982d543..88639bc9b5 100644
--- a/src/basic/meson.build
+++ b/src/basic/meson.build
@@ -176,6 +176,8 @@ basic_sources = files('''
         path-lookup.h
         path-util.c
         path-util.h
+        percent-util.c
+        percent-util.h
         prioq.c
         prioq.h
         proc-cmdline.c
diff --git a/src/basic/parse-util.c b/src/basic/parse-util.c
index 97d224f165..b79c885dfd 100644
--- a/src/basic/parse-util.c
+++ b/src/basic/parse-util.c
@@ -627,146 +627,6 @@ int parse_fractional_part_u(const char **p, size_t digits, unsigned *res) {
         return 0;
 }
 
-static int parse_parts_value_whole(const char *p, const char *symbol) {
-        const char *pc, *n;
-        int r, v;
-
-        pc = endswith(p, symbol);
-        if (!pc)
-                return -EINVAL;
-
-        n = strndupa(p, pc - p);
-        r = safe_atoi(n, &v);
-        if (r < 0)
-                return r;
-        if (v < 0)
-                return -ERANGE;
-
-        return v;
-}
-
-static int parse_parts_value_with_tenths_place(const char *p, const char *symbol) {
-        const char *pc, *dot, *n;
-        int r, q, v;
-
-        pc = endswith(p, symbol);
-        if (!pc)
-                return -EINVAL;
-
-        dot = memchr(p, '.', pc - p);
-        if (dot) {
-                if (dot + 2 != pc)
-                        return -EINVAL;
-                if (dot[1] < '0' || dot[1] > '9')
-                        return -EINVAL;
-                q = dot[1] - '0';
-                n = strndupa(p, dot - p);
-        } else {
-                q = 0;
-                n = strndupa(p, pc - p);
-        }
-        r = safe_atoi(n, &v);
-        if (r < 0)
-                return r;
-        if (v < 0)
-                return -ERANGE;
-        if (v > (INT_MAX - q) / 10)
-                return -ERANGE;
-
-        v = v * 10 + q;
-        return v;
-}
-
-static int parse_parts_value_with_hundredths_place(const char *p, const char *symbol) {
-        const char *pc, *dot, *n;
-        int r, q, v;
-
-        pc = endswith(p, symbol);
-        if (!pc)
-                return -EINVAL;
-
-        dot = memchr(p, '.', pc - p);
-        if (dot) {
-                if (dot + 3 != pc)
-                        return -EINVAL;
-                if (dot[1] < '0' || dot[1] > '9' || dot[2] < '0' || dot[2] > '9')
-                        return -EINVAL;
-                q = (dot[1] - '0') * 10 + (dot[2] - '0');
-                n = strndupa(p, dot - p);
-        } else {
-                q = 0;
-                n = strndupa(p, pc - p);
-        }
-        r = safe_atoi(n, &v);
-        if (r < 0)
-                return r;
-        if (v < 0)
-                return -ERANGE;
-        if (v > (INT_MAX - q) / 100)
-                return -ERANGE;
-
-        v = v * 100 + q;
-        return v;
-}
-
-int parse_percent_unbounded(const char *p) {
-        return parse_parts_value_whole(p, "%");
-}
-
-int parse_percent(const char *p) {
-        int v;
-
-        v = parse_percent_unbounded(p);
-        if (v > 100)
-                return -ERANGE;
-
-        return v;
-}
-
-int parse_permille_unbounded(const char *p) {
-        const char *pm;
-
-        pm = endswith(p, "‰");
-        if (pm)
-                return parse_parts_value_whole(p, "‰");
-
-        return parse_parts_value_with_tenths_place(p, "%");
-}
-
-int parse_permille(const char *p) {
-        int v;
-
-        v = parse_permille_unbounded(p);
-        if (v > 1000)
-                return -ERANGE;
-
-        return v;
-}
-
-int parse_permyriad_unbounded(const char *p) {
-        const char *pm;
-
-        pm = endswith(p, "‱");
-        if (pm)
-                return parse_parts_value_whole(p, "‱");
-
-        pm = endswith(p, "‰");
-        if (pm)
-                return parse_parts_value_with_tenths_place(p, "‰");
-
-        return parse_parts_value_with_hundredths_place(p, "%");
-}
-
-int parse_permyriad(const char *p) {
-        int v;
-
-        v = parse_permyriad_unbounded(p);
-        if (v > 10000)
-                return -ERANGE;
-
-        return v;
-}
-
 int parse_nice(const char *p, int *ret) {
         int n, r;
 
diff --git a/src/basic/parse-util.h b/src/basic/parse-util.h
index 29e04cf562..908202dafd 100644
--- a/src/basic/parse-util.h
+++ b/src/basic/parse-util.h
@@ -127,15 +127,6 @@ int safe_atod(const char *s, double *ret_d);
 
 int parse_fractional_part_u(const char **s, size_t digits, unsigned *res);
 
-int parse_percent_unbounded(const char *p);
-int parse_percent(const char *p);
-
-int parse_permille_unbounded(const char *p);
-int parse_permille(const char *p);
-
-int parse_permyriad_unbounded(const char *p);
-int parse_permyriad(const char *p);
-
 int parse_nice(const char *p, int *ret);
 
 int parse_ip_port(const char *s, uint16_t *ret);
diff --git a/src/basic/percent-util.c b/src/basic/percent-util.c
new file mode 100644
index 0000000000..06f20fd61e
--- /dev/null
+++ b/src/basic/percent-util.c
@@ -0,0 +1,157 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include "percent-util.h"
+#include "string-util.h"
+#include "parse-util.h"
+
+static int parse_parts_value_whole(const char *p, const char *symbol) {
+        const char *pc, *n;
+        int r, v;
+
+        pc = endswith(p, symbol);
+        if (!pc)
+                return -EINVAL;
+
+        n = strndupa(p, pc - p);
+        r = safe_atoi(n, &v);
+        if (r < 0)
+                return r;
+        if (v < 0)
+                return -ERANGE;
+
+        return v;
+}
+
+static int parse_parts_value_with_tenths_place(const char *p, const char *symbol) {
+        const char *pc, *dot, *n;
+        int r, q, v;
+
+        pc = endswith(p, symbol);
+        if (!pc)
+                return -EINVAL;
+
+        dot = memchr(p, '.', pc - p);
+        if (dot) {
+                if (dot + 2 != pc)
+                        return -EINVAL;
+                if (dot[1] < '0' || dot[1] > '9')
+                        return -EINVAL;
+                q = dot[1] - '0';
+                n = strndupa(p, dot - p);
+        } else {
+                q = 0;
+                n = strndupa(p, pc - p);
+        }
+        r = safe_atoi(n, &v);
+        if (r < 0)
+                return r;
+        if (v < 0)
+                return -ERANGE;
+        if (v > (INT_MAX - q) / 10)
+                return -ERANGE;
+
+        v = v * 10 + q;
+        return v;
+}
+
+static int parse_parts_value_with_hundredths_place(const char *p, const char *symbol) {
+        const char *pc, *dot, *n;
+        int r, q, v;
+
+        pc = endswith(p, symbol);
+        if (!pc)
+                return -EINVAL;
+
+        dot = memchr(p, '.', pc - p);
+        if (dot) {
+                if (dot + 3 == pc) {
+                        /* Support two places after the dot */
+
+                        if (dot[1] < '0' || dot[1] > '9' || dot[2] < '0' || dot[2] > '9')
+                                return -EINVAL;
+                        q = (dot[1] - '0') * 10 + (dot[2] - '0');
+
+                } else if (dot + 2 == pc) {
+                        /* Support one place after the dot */
+
+                        if (dot[1] < '0' || dot[1] > '9')
+                                return -EINVAL;
+                        q = (dot[1] - '0') * 10;
+                } else
+                        /* We do not support zero or more than two places */
+                        return -EINVAL;
+
+                n = strndupa(p, dot - p);
+        } else {
+                q = 0;
+                n = strndupa(p, pc - p);
+        }
+        r = safe_atoi(n, &v);
+        if (r < 0)
+                return r;
+        if (v < 0)
+                return -ERANGE;
+        if (v > (INT_MAX - q) / 100)
+                return -ERANGE;
+
+        v = v * 100 + q;
+        return v;
+}
+
+int parse_percent_unbounded(const char *p) {
+        return parse_parts_value_whole(p, "%");
+}
+
+int parse_percent(const char *p) {
+        int v;
+
+        v = parse_percent_unbounded(p);
+        if (v > 100)
+                return -ERANGE;
+
+        return v;
+}
+
+int parse_permille_unbounded(const char *p) {
+        const char *pm;
+
+        pm = endswith(p, "‰");
+        if (pm)
+                return parse_parts_value_whole(p, "‰");
+
+        return parse_parts_value_with_tenths_place(p, "%");
+}
+
+int parse_permille(const char *p) {
+        int v;
+
+        v = parse_permille_unbounded(p);
+        if (v > 1000)
+                return -ERANGE;
+
+        return v;
+}
+
+int parse_permyriad_unbounded(const char *p) {
+        const char *pm;
+
+        pm = endswith(p, "‱");
+        if (pm)
+                return parse_parts_value_whole(p, "‱");
+
+        pm = endswith(p, "‰");
+        if (pm)
+                return parse_parts_value_with_tenths_place(p, "‰");
+
+        return parse_parts_value_with_hundredths_place(p, "%");
+}
+
+int parse_permyriad(const char *p) {
+        int v;
+
+        v = parse_permyriad_unbounded(p);
+        if (v > 10000)
+                return -ERANGE;
+
+        return v;
+}
diff --git a/src/basic/percent-util.h b/src/basic/percent-util.h
new file mode 100644
index 0000000000..24f4c3bdef
--- /dev/null
+++ b/src/basic/percent-util.h
@@ -0,0 +1,64 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+#pragma once
+
+#include <errno.h>
+#include <inttypes.h>
+
+#include "macro.h"
+
+int parse_percent_unbounded(const char *p);
+int parse_percent(const char *p);
+
+int parse_permille_unbounded(const char *p);
+int parse_permille(const char *p);
+
+int parse_permyriad_unbounded(const char *p);
+int parse_permyriad(const char *p);
+
+/* Some macro-like helpers that convert a percent/permille/permyriad value (as parsed by parse_percent()) to
+ * a value relative to 100% == 2^32-1. Rounds to closest. */
+static inline uint32_t UINT32_SCALE_FROM_PERCENT(int percent) {
+        assert_cc(INT_MAX <= UINT32_MAX);
+        return (uint32_t) (((uint64_t) percent * UINT32_MAX + 50) / 100U);
+}
+
+static inline uint32_t UINT32_SCALE_FROM_PERMILLE(int permille) {
+        return (uint32_t) (((uint64_t) permille * UINT32_MAX + 500) / 1000U);
+}
+
+static inline uint32_t UINT32_SCALE_FROM_PERMYRIAD(int permyriad) {
+        return (uint32_t) (((uint64_t) permyriad * UINT32_MAX + 5000) / 10000U);
+}
+
+static inline int UINT32_SCALE_TO_PERCENT(uint32_t scale) {
+        uint32_t u;
+
+        u = (uint32_t) ((((uint64_t) scale) * 100U + UINT32_MAX/2) / UINT32_MAX);
+        if (u > INT_MAX)
+                return -ERANGE;
+
+        return (int) u;
+}
+
+static inline int UINT32_SCALE_TO_PERMILLE(uint32_t scale) {
+        uint32_t u;
+
+        u = (uint32_t) ((((uint64_t) scale) * 1000U + UINT32_MAX/2) / UINT32_MAX);
+        if (u > INT_MAX)
+                return -ERANGE;
+
+        return (int) u;
+}
+
+static inline int UINT32_SCALE_TO_PERMYRIAD(uint32_t scale) {
+        uint32_t u;
+
+        u = (uint32_t) ((((uint64_t) scale) * 10000U + UINT32_MAX/2) / UINT32_MAX);
+        if (u > INT_MAX)
+                return -ERANGE;
+
+        return (int) u;
+}
+
+#define PERMYRIAD_AS_PERCENT_FORMAT_STR "%i.%02i%%"
+#define PERMYRIAD_AS_PERCENT_FORMAT_VAL(x) ((x)/100), ((x)%100)
diff --git a/src/core/cgroup.c b/src/core/cgroup.c
index b0fc67a125..1f74cb393f 100644
--- a/src/core/cgroup.c
+++ b/src/core/cgroup.c
@@ -21,6 +21,7 @@
 #include "nulstr-util.h"
 #include "parse-util.h"
 #include "path-util.h"
+#include "percent-util.h"
 #include "process-util.h"
 #include "procfs-util.h"
 #include "special.h"
@@ -418,7 +419,7 @@ void cgroup_context_dump(Unit *u, FILE* f, const char *prefix) {
                 "%sDelegate: %s\n"
                 "%sManagedOOMSwap: %s\n"
                 "%sManagedOOMMemoryPressure: %s\n"
-                "%sManagedOOMMemoryPressureLimit: %" PRIu32 ".%02" PRIu32 "%%\n"
+                "%sManagedOOMMemoryPressureLimit: " PERMYRIAD_AS_PERCENT_FORMAT_STR "\n"
                 "%sManagedOOMPreference: %s%%\n",
                 prefix, yes_no(c->cpu_accounting),
                 prefix, yes_no(c->io_accounting),
@@ -452,7 +453,7 @@ void cgroup_context_dump(Unit *u, FILE* f, const char *prefix) {
                 prefix, yes_no(c->delegate),
                 prefix, managed_oom_mode_to_string(c->moom_swap),
                 prefix, managed_oom_mode_to_string(c->moom_mem_pressure),
-                prefix, c->moom_mem_pressure_limit_permyriad / 100, c->moom_mem_pressure_limit_permyriad % 100,
+                prefix, PERMYRIAD_AS_PERCENT_FORMAT_VAL(UINT32_SCALE_TO_PERMYRIAD(c->moom_mem_pressure_limit)),
                 prefix, managed_oom_preference_to_string(c->moom_preference));
 
         if (c->delegate) {
diff --git a/src/core/cgroup.h b/src/core/cgroup.h
index 8183551420..fa79ba1523 100644
--- a/src/core/cgroup.h
+++ b/src/core/cgroup.h
@@ -163,7 +163,7 @@ struct CGroupContext {
         /* Settings for systemd-oomd */
         ManagedOOMMode moom_swap;
         ManagedOOMMode moom_mem_pressure;
-        uint32_t moom_mem_pressure_limit_permyriad;
+        uint32_t moom_mem_pressure_limit; /* Normalized to 2^32-1 == 100% */
         ManagedOOMPreference moom_preference;
 };
 
diff --git a/src/core/core-varlink.c b/src/core/core-varlink.c
index df542e82d1..d695106658 100644
--- a/src/core/core-varlink.c
+++ b/src/core/core-varlink.c
@@ -83,7 +83,7 @@ static int build_managed_oom_json_array_element(Unit *u, const char *property, J
                                  JSON_BUILD_PAIR("mode", JSON_BUILD_STRING(mode)),
                                  JSON_BUILD_PAIR("path", JSON_BUILD_STRING(u->cgroup_path)),
                                  JSON_BUILD_PAIR("property", JSON_BUILD_STRING(property)),
-                                 JSON_BUILD_PAIR_CONDITION(use_limit, "limit", JSON_BUILD_UNSIGNED(c->moom_mem_pressure_limit_permyriad))));
+                                 JSON_BUILD_PAIR_CONDITION(use_limit, "limit", JSON_BUILD_UNSIGNED(c->moom_mem_pressure_limit))));
 }
 
 int manager_varlink_send_managed_oom_update(Unit *u) {
diff --git a/src/core/dbus-cgroup.c b/src/core/dbus-cgroup.c
index 6652c212f1..04d2ba34f3 100644
--- a/src/core/dbus-cgroup.c
+++ b/src/core/dbus-cgroup.c
@@ -16,6 +16,7 @@
 #include "fileio.h"
 #include "limits-util.h"
 #include "path-util.h"
+#include "percent-util.h"
 
 BUS_DEFINE_PROPERTY_GET(bus_property_get_tasks_max, "t", TasksMax, tasks_max_resolve);
 
@@ -395,7 +396,7 @@ const sd_bus_vtable bus_cgroup_vtable[] = {
         SD_BUS_PROPERTY("DisableControllers", "as", property_get_cgroup_mask, offsetof(CGroupContext, disable_controllers), 0),
         SD_BUS_PROPERTY("ManagedOOMSwap", "s", property_get_managed_oom_mode, offsetof(CGroupContext, moom_swap), 0),
         SD_BUS_PROPERTY("ManagedOOMMemoryPressure", "s", property_get_managed_oom_mode, offsetof(CGroupContext, moom_mem_pressure), 0),
-        SD_BUS_PROPERTY("ManagedOOMMemoryPressureLimitPermyriad", "u", NULL, offsetof(CGroupContext, moom_mem_pressure_limit_permyriad), 0),
+        SD_BUS_PROPERTY("ManagedOOMMemoryPressureLimit", "u", NULL, offsetof(CGroupContext, moom_mem_pressure_limit), 0),
         SD_BUS_PROPERTY("ManagedOOMPreference", "s", property_get_managed_oom_preference, offsetof(CGroupContext, moom_preference), 0),
         SD_BUS_VTABLE_END
 };
@@ -704,10 +705,10 @@ static int bus_cgroup_set_boolean(
                         /* Prepare to chop off suffix */                \
                         assert_se(endswith(name, "Scale"));             \
                                                                         \
-                        uint32_t scaled = DIV_ROUND_UP((uint64_t) raw * 1000, (uint64_t) UINT32_MAX); \
-                        unit_write_settingf(u, flags, name, "%.*s=%" PRIu32 ".%" PRIu32 "%%", \
+                        int scaled = UINT32_SCALE_TO_PERMYRIAD(raw);    \
+                        unit_write_settingf(u, flags, name, "%.*s=" PERMYRIAD_AS_PERCENT_FORMAT_STR, \
                                             (int)(strlen(name) - strlen("Scale")), name, \
-                                            scaled / 10, scaled % 10);  \
+                                            PERMYRIAD_AS_PERCENT_FORMAT_VAL(scaled)); \
                 }                                                       \
                                                                         \
                 return 1;                                               \
@@ -1698,7 +1699,7 @@ int bus_cgroup_set_property(
                 return 1;
         }
 
-        if (streq(name, "ManagedOOMMemoryPressureLimitPermyriad")) {
+        if (streq(name, "ManagedOOMMemoryPressureLimit")) {
                 uint32_t v;
 
                 if (!UNIT_VTABLE(u)->can_set_managed_oom)
@@ -1708,12 +1709,11 @@ int bus_cgroup_set_property(
                 if (r < 0)
                         return r;
 
-                if (v > 10000)
-                        return -ERANGE;
-
                 if (!UNIT_WRITE_FLAGS_NOOP(flags)) {
-                        c->moom_mem_pressure_limit_permyriad = v;
-                        unit_write_settingf(u, flags, name, "ManagedOOMMemoryPressureLimit=%" PRIu32 ".%02" PRIu32 "%%", v / 100, v % 100);
+                        c->moom_mem_pressure_limit = v;
+                        unit_write_settingf(u, flags, name,
+                                            "ManagedOOMMemoryPressureLimit=" PERMYRIAD_AS_PERCENT_FORMAT_STR,
+                                            PERMYRIAD_AS_PERCENT_FORMAT_VAL(UINT32_SCALE_TO_PERMYRIAD(v)));
                 }
 
                 if (c->moom_mem_pressure == MANAGED_OOM_KILL)
diff --git a/src/core/load-fragment-gperf.gperf.m4 b/src/core/load-fragment-gperf.gperf.m4
index b0460e2764..6ed6b07db2 100644
--- a/src/core/load-fragment-gperf.gperf.m4
+++ b/src/core/load-fragment-gperf.gperf.m4
@@ -229,7 +229,7 @@ $1.IPIngressFilterPath,                  config_parse_ip_filter_bpf_progs,
 $1.IPEgressFilterPath,                   config_parse_ip_filter_bpf_progs,            0,                                  offsetof($1, cgroup_context.ip_filters_egress)
 $1.ManagedOOMSwap,                       config_parse_managed_oom_mode,               0,                                  offsetof($1, cgroup_context.moom_swap)
 $1.ManagedOOMMemoryPressure,             config_parse_managed_oom_mode,               0,                                  offsetof($1, cgroup_context.moom_mem_pressure)
-$1.ManagedOOMMemoryPressureLimit,        config_parse_managed_oom_mem_pressure_limit, 0,                                  offsetof($1, cgroup_context.moom_mem_pressure_limit_permyriad)
+$1.ManagedOOMMemoryPressureLimit,        config_parse_managed_oom_mem_pressure_limit, 0,                                  offsetof($1, cgroup_context.moom_mem_pressure_limit)
 $1.ManagedOOMPreference,                 config_parse_managed_oom_preference,         0,                                  offsetof($1, cgroup_context.moom_preference)
 $1.NetClass,                             config_parse_warn_compat,                    DISABLED_LEGACY,                    0'
 )m4_dnl
diff --git a/src/core/load-fragment.c b/src/core/load-fragment.c
index 11836c0938..b9fc450ac7 100644
--- a/src/core/load-fragment.c
+++ b/src/core/load-fragment.c
@@ -46,6 +46,7 @@
 #include "nulstr-util.h"
 #include "parse-util.h"
 #include "path-util.h"
+#include "percent-util.h"
 #include "process-util.h"
 #if HAVE_SECCOMP
 #include "seccomp-util.h"
@@ -3593,13 +3594,13 @@ int config_parse_cpu_quota(
                 return 0;
         }
 
-        r = parse_permille_unbounded(rvalue);
+        r = parse_permyriad_unbounded(rvalue);
         if (r <= 0) {
                 log_syntax(unit, LOG_WARNING, filename, line, r, "Invalid CPU quota '%s', ignoring.", rvalue);
                 return 0;
         }
 
-        c->cpu_quota_per_sec_usec = ((usec_t) r * USEC_PER_SEC) / 1000U;
+        c->cpu_quota_per_sec_usec = ((usec_t) r * USEC_PER_SEC) / 10000U;
         return 0;
 }
 
@@ -3664,7 +3665,7 @@ int config_parse_memory_limit(
                 bytes = CGROUP_LIMIT_MIN;
         else if (!isempty(rvalue) && !streq(rvalue, "infinity")) {
 
-                r = parse_permille(rvalue);
+                r = parse_permyriad(rvalue);
                 if (r < 0) {
                         r = parse_size(rvalue, 1024, &bytes);
                         if (r < 0) {
@@ -3672,7 +3673,7 @@ int config_parse_memory_limit(
                                 return 0;
                         }
                 } else
-                        bytes = physical_memory_scale(r, 1000U);
+                        bytes = physical_memory_scale(r, 10000U);
 
                 if (bytes >= UINT64_MAX ||
                     (bytes <= 0 && !STR_IN_SET(lvalue, "MemorySwapMax", "MemoryLow", "MemoryMin", "DefaultMemoryLow", "DefaultMemoryMin"))) {
@@ -3734,9 +3735,9 @@ int config_parse_tasks_max(
                 return 0;
         }
 
-        r = parse_permille(rvalue);
+        r = parse_permyriad(rvalue);
         if (r >= 0)
-                *tasks_max = (TasksMax) { r, 1000U }; /* r‰ */
+                *tasks_max = (TasksMax) { r, 10000U }; /* r‱ */
         else {
                 r = safe_atou64(rvalue, &v);
                 if (r < 0) {
@@ -3842,6 +3843,7 @@ int config_parse_managed_oom_mode(
                 const char *rvalue,
                 void *data,
                 void *userdata) {
+
         ManagedOOMMode *mode = data, m;
         UnitType t;
 
@@ -3861,6 +3863,7 @@ int config_parse_managed_oom_mode(
                 log_syntax(unit, LOG_WARNING, filename, line, m, "Invalid syntax, ignoring: %s", rvalue);
                 return 0;
         }
+
         *mode = m;
         return 0;
 }
@@ -3876,6 +3879,7 @@ int config_parse_managed_oom_mem_pressure_limit(
                 const char *rvalue,
                 void *data,
                 void *userdata) {
+
         uint32_t *limit = data;
         UnitType t;
         int r;
@@ -3897,7 +3901,8 @@ int config_parse_managed_oom_mem_pressure_limit(
                 return 0;
         }
 
-        *limit = r;
+        /* Normalize to 2^32-1 == 100% */
+        *limit = UINT32_SCALE_FROM_PERMYRIAD(r);
         return 0;
 }
 
diff --git a/src/core/main.c b/src/core/main.c
index f29449d691..67189fef6d 100644
--- a/src/core/main.c
+++ b/src/core/main.c
@@ -1256,8 +1256,8 @@ static int bump_rlimit_memlock(struct rlimit *saved_rlimit) {
          * must be unsigned, hence this is a given, but let's make this clear here. */
         assert_cc(RLIM_INFINITY > 0);
 
-        mm = physical_memory() / 8; /* Let's scale how much we allow to be locked by the amount of physical
-                                     * RAM. We allow an eighth to be locked by us, just to pick a value. */
+        mm = physical_memory_scale(1, 8); /* Let's scale how much we allow to be locked by the amount of physical
+                                           * RAM. We allow an eighth to be locked by us, just to pick a value. */
 
         new_rlimit = (struct rlimit) {
                 .rlim_cur = MAX3(HIGH_RLIMIT_MEMLOCK, saved_rlimit->rlim_cur, mm),
diff --git a/src/home/homectl.c b/src/home/homectl.c
index fa9d11e69d..d59dfb1f60 100644
--- a/src/home/homectl.c
+++ b/src/home/homectl.c
@@ -26,6 +26,7 @@
 #include "parse-argument.h"
 #include "parse-util.h"
 #include "path-util.h"
+#include "percent-util.h"
 #include "pkcs11-util.h"
 #include "pretty-print.h"
 #include "process-util.h"
@@ -1567,7 +1568,7 @@ static int resize_home(int argc, char *argv[], void *userdata) {
         (void) polkit_agent_open_if_enabled(arg_transport, arg_ask_password);
 
         if (arg_disk_size_relative != UINT64_MAX ||
-            (argc > 2 && parse_percent(argv[2]) >= 0))
+            (argc > 2 && parse_permyriad(argv[2]) >= 0))
                 return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP),
                                                "Relative disk size specification currently not supported when resizing.");
 
@@ -2653,7 +2654,7 @@ static int parse_argv(int argc, char *argv[]) {
                                 break;
                         }
 
-                        r = parse_permille(optarg);
+                        r = parse_permyriad(optarg);
                         if (r < 0) {
                                 r = parse_size(optarg, 1024, &arg_disk_size);
                                 if (r < 0)
@@ -2670,7 +2671,7 @@ static int parse_argv(int argc, char *argv[]) {
                                 arg_disk_size_relative = UINT64_MAX;
                         } else {
                                 /* Normalize to UINT32_MAX == 100% */
-                                arg_disk_size_relative = (uint64_t) r * UINT32_MAX / 1000U;
+                                arg_disk_size_relative = UINT32_SCALE_FROM_PERMYRIAD(r);
 
                                 r = drop_from_identity("diskSize");
                                 if (r < 0)
diff --git a/src/import/importd.c b/src/import/importd.c
index 9ac2f8dcfe..f9e8481a6d 100644
--- a/src/import/importd.c
+++ b/src/import/importd.c
@@ -22,6 +22,7 @@
 #include "mkdir.h"
 #include "parse-util.h"
 #include "path-util.h"
+#include "percent-util.h"
 #include "process-util.h"
 #include "service-util.h"
 #include "signal-util.h"
diff --git a/src/login/logind-user.c b/src/login/logind-user.c
index 9b3ec07906..a2c468e8dd 100644
--- a/src/login/logind-user.c
+++ b/src/login/logind-user.c
@@ -19,11 +19,12 @@
 #include "label.h"
 #include "limits-util.h"
 #include "logind-dbus.h"
-#include "logind-user.h"
 #include "logind-user-dbus.h"
+#include "logind-user.h"
 #include "mkdir.h"
 #include "parse-util.h"
 #include "path-util.h"
+#include "percent-util.h"
 #include "rm-rf.h"
 #include "serialize.h"
 #include "special.h"
@@ -907,9 +908,9 @@ int config_parse_tmpfs_size(
         assert(data);
 
         /* First, try to parse as percentage */
-        r = parse_permille(rvalue);
-        if (r > 0 && r < 1000)
-                *sz = physical_memory_scale(r, 1000U);
+        r = parse_permyriad(rvalue);
+        if (r > 0)
+                *sz = physical_memory_scale(r, 10000U);
         else {
                 uint64_t k;
 
diff --git a/src/login/pam_systemd.c b/src/login/pam_systemd.c
index 8e7a94db55..a23200b3b5 100644
--- a/src/login/pam_systemd.c
+++ b/src/login/pam_systemd.c
@@ -34,6 +34,7 @@
 #include "pam-util.h"
 #include "parse-util.h"
 #include "path-util.h"
+#include "percent-util.h"
 #include "process-util.h"
 #include "rlimit-util.h"
 #include "socket-util.h"
@@ -334,9 +335,9 @@ static int append_session_memory_max(pam_handle_t *handle, sd_bus_message *m, co
                 return PAM_SUCCESS;
         }
 
-        r = parse_permille(limit);
+        r = parse_permyriad(limit);
         if (r >= 0) {
-                r = sd_bus_message_append(m, "(sv)", "MemoryMaxScale", "u", (uint32_t) (((uint64_t) r * UINT32_MAX) / 1000U));
+                r = sd_bus_message_append(m, "(sv)", "MemoryMaxScale", "u", UINT32_SCALE_FROM_PERMYRIAD(r));
                 if (r < 0)
                         return pam_bus_log_create_error(handle, r);
 
diff --git a/src/network/tc/tc-util.c b/src/network/tc/tc-util.c
index 3e10b50c96..3781182946 100644
--- a/src/network/tc/tc-util.c
+++ b/src/network/tc/tc-util.c
@@ -5,6 +5,7 @@
 #include "extract-word.h"
 #include "fileio.h"
 #include "parse-util.h"
+#include "percent-util.h"
 #include "tc-util.h"
 #include "time-util.h"
 
@@ -57,17 +58,17 @@ int tc_time_to_tick(usec_t t, uint32_t *ret) {
         return 0;
 }
 
-int parse_tc_percent(const char *s, uint32_t *percent) {
+int parse_tc_percent(const char *s, uint32_t *ret_fraction) {
         int r;
 
         assert(s);
-        assert(percent);
+        assert(ret_fraction);
 
-        r = parse_permille(s);
+        r = parse_permyriad(s);
         if (r < 0)
                 return r;
 
-        *percent = (double) r / 1000 * UINT32_MAX;
+        *ret_fraction = (double) r / 10000 * UINT32_MAX;
         return 0;
 }
 
diff --git a/src/oom/oomd-manager.c b/src/oom/oomd-manager.c
index bdf41807b2..fad1fb0d45 100644
--- a/src/oom/oomd-manager.c
+++ b/src/oom/oomd-manager.c
@@ -10,12 +10,13 @@
 #include "oomd-manager-bus.h"
 #include "oomd-manager.h"
 #include "path-util.h"
+#include "percent-util.h"
 
 typedef struct ManagedOOMReply {
         ManagedOOMMode mode;
         char *path;
         char *property;
-        unsigned limit;
+        uint32_t limit;
 } ManagedOOMReply;
 
 static void managed_oom_reply_destroy(ManagedOOMReply *reply) {
@@ -52,10 +53,10 @@ static int process_managed_oom_reply(
         assert(m);
 
         static const JsonDispatch dispatch_table[] = {
-                { "mode",     JSON_VARIANT_STRING,   managed_oom_mode,       offsetof(ManagedOOMReply, mode),     JSON_MANDATORY },
-                { "path",     JSON_VARIANT_STRING,   json_dispatch_string,   offsetof(ManagedOOMReply, path),     JSON_MANDATORY },
-                { "property", JSON_VARIANT_STRING,   json_dispatch_string,   offsetof(ManagedOOMReply, property), JSON_MANDATORY },
-                { "limit",    JSON_VARIANT_UNSIGNED, json_dispatch_unsigned, offsetof(ManagedOOMReply, limit),    0 },
+                { "mode",     JSON_VARIANT_STRING,   managed_oom_mode,     offsetof(ManagedOOMReply, mode),     JSON_MANDATORY },
+                { "path",     JSON_VARIANT_STRING,   json_dispatch_string, offsetof(ManagedOOMReply, path),     JSON_MANDATORY },
+                { "property", JSON_VARIANT_STRING,   json_dispatch_string, offsetof(ManagedOOMReply, property), JSON_MANDATORY },
+                { "limit",    JSON_VARIANT_UNSIGNED, json_dispatch_uint32, offsetof(ManagedOOMReply, limit),    0 },
                 {},
         };
 
@@ -86,7 +87,8 @@ static int process_managed_oom_reply(
                 if (ret == -ENOMEM) {
                         r = ret;
                         goto finish;
-                } else if (ret < 0)
+                }
+                if (ret < 0)
                         continue;
 
                 monitor_hm = streq(reply.property, "ManagedOOMSwap") ?
@@ -99,14 +101,15 @@ static int process_managed_oom_reply(
 
                 limit = m->default_mem_pressure_limit;
 
-                if (streq(reply.property, "ManagedOOMMemoryPressure")) {
-                        if (reply.limit > 10000)
+                if (streq(reply.property, "ManagedOOMMemoryPressure") && reply.limit > 0) {
+                        int permyriad = UINT32_SCALE_TO_PERMYRIAD(reply.limit);
+
+                        ret = store_loadavg_fixed_point(
+                                        (unsigned long) permyriad / 100,
+                                        (unsigned long) permyriad % 100,
+                                        &limit);
+                        if (ret < 0)
                                 continue;
-                        else if (reply.limit != 0) {
-                                ret = store_loadavg_fixed_point((unsigned long) reply.limit / 100, (unsigned long) reply.limit % 100, &limit);
-                                if (ret < 0)
-                                        continue;
-                        }
                 }
 
                 ret = oomd_insert_cgroup_context(NULL, monitor_hm, empty_to_root(reply.path));
@@ -348,11 +351,11 @@ static int monitor_cgroup_contexts_handler(sd_event_source *s, uint64_t usec, vo
                 }
         }
 
-        if (oomd_swap_free_below(&m->system_context, (100 - m->swap_used_limit))) {
+        if (oomd_swap_free_below(&m->system_context, 10000 - m->swap_used_limit_permyriad)) {
                 _cleanup_hashmap_free_ Hashmap *candidates = NULL;
 
-                log_notice("Swap used (%"PRIu64") / total (%"PRIu64") is more than %u%%",
-                        m->system_context.swap_used, m->system_context.swap_total, m->swap_used_limit);
+                log_notice("Swap used (%"PRIu64") / total (%"PRIu64") is more than " PERMYRIAD_AS_PERCENT_FORMAT_STR,
+                           m->system_context.swap_used, m->system_context.swap_total, PERMYRIAD_AS_PERCENT_FORMAT_VAL(m->swap_used_limit_permyriad));
 
                 r = get_monitored_cgroup_contexts_candidates(m->monitored_swap_cgroup_contexts, &candidates);
                 if (r == -ENOMEM)
@@ -478,7 +481,13 @@ static int manager_connect_bus(Manager *m) {
         return 0;
 }
 
-int manager_start(Manager *m, bool dry_run, int swap_used_limit, int mem_pressure_limit_permyriad, usec_t mem_pressure_usec) {
+int manager_start(
+                Manager *m,
+                bool dry_run,
+                int swap_used_limit_permyriad,
+                int mem_pressure_limit_permyriad,
+                usec_t mem_pressure_usec) {
+
         unsigned long l, f;
         int r;
 
@@ -486,10 +495,10 @@ int manager_start(Manager *m, bool dry_run, int swap_used_limit, int mem_pressur
 
         m->dry_run = dry_run;
 
-        m->swap_used_limit = swap_used_limit != -1 ? swap_used_limit : DEFAULT_SWAP_USED_LIMIT;
-        assert(m->swap_used_limit <= 100);
+        m->swap_used_limit_permyriad = swap_used_limit_permyriad >= 0 ? swap_used_limit_permyriad : DEFAULT_SWAP_USED_LIMIT_PERCENT * 100;
+        assert(m->swap_used_limit_permyriad <= 10000);
 
-        if (mem_pressure_limit_permyriad != -1) {
+        if (mem_pressure_limit_permyriad >= 0) {
                 assert(mem_pressure_limit_permyriad <= 10000);
 
                 l = mem_pressure_limit_permyriad / 100;
@@ -537,12 +546,12 @@ int manager_get_dump_string(Manager *m, char **ret) {
 
         fprintf(f,
                 "Dry Run: %s\n"
-                "Swap Used Limit: %u%%\n"
+                "Swap Used Limit: " PERMYRIAD_AS_PERCENT_FORMAT_STR "\n"
                 "Default Memory Pressure Limit: %lu.%02lu%%\n"
                 "Default Memory Pressure Duration: %s\n"
                 "System Context:\n",
                 yes_no(m->dry_run),
-                m->swap_used_limit,
+                PERMYRIAD_AS_PERCENT_FORMAT_VAL(m->swap_used_limit_permyriad),
                 LOAD_INT(m->default_mem_pressure_limit), LOAD_FRAC(m->default_mem_pressure_limit),
                 format_timespan(buf, sizeof(buf), m->default_mem_pressure_duration_usec, USEC_PER_SEC));
         oomd_dump_system_context(&m->system_context, f, "\t");
diff --git a/src/oom/oomd-manager.h b/src/oom/oomd-manager.h
index 50f10021c7..9ab8494c6d 100644
--- a/src/oom/oomd-manager.h
+++ b/src/oom/oomd-manager.h
@@ -18,7 +18,7 @@
  * system.slice are assumed to be less latency sensitive. */
 #define DEFAULT_MEM_PRESSURE_DURATION_USEC (30 * USEC_PER_SEC)
 #define DEFAULT_MEM_PRESSURE_LIMIT_PERCENT 60
-#define DEFAULT_SWAP_USED_LIMIT 90
+#define DEFAULT_SWAP_USED_LIMIT_PERCENT 90
 
 #define RECLAIM_DURATION_USEC (30 * USEC_PER_SEC)
 #define POST_ACTION_DELAY_USEC (15 * USEC_PER_SEC)
@@ -32,7 +32,7 @@ struct Manager {
         Hashmap *polkit_registry;
 
         bool dry_run;
-        unsigned swap_used_limit;
+        int swap_used_limit_permyriad;
         loadavg_t default_mem_pressure_limit;
         usec_t default_mem_pressure_duration_usec;
 
@@ -56,7 +56,7 @@ DEFINE_TRIVIAL_CLEANUP_FUNC(Manager*, manager_free);
 
 int manager_new(Manager **ret);
 
-int manager_start(Manager *m, bool dry_run, int swap_used_limit, int mem_pressure_limit_permyriad, usec_t mem_pressure_usec);
+int manager_start(Manager *m, bool dry_run, int swap_used_limit_permyriad, int mem_pressure_limit_permyriad, usec_t mem_pressure_usec);
 
 int manager_get_dump_string(Manager *m, char **ret);
 
diff --git a/src/oom/oomd-util.c b/src/oom/oomd-util.c
index 9dd9b17c6d..b054ccacc4 100644
--- a/src/oom/oomd-util.c
+++ b/src/oom/oomd-util.c
@@ -134,13 +134,13 @@ bool oomd_memory_reclaim(Hashmap *h) {
         return pgscan_of > last_pgscan_of;
 }
 
-bool oomd_swap_free_below(const OomdSystemContext *ctx, uint64_t threshold_percent) {
+bool oomd_swap_free_below(const OomdSystemContext *ctx, int threshold_permyriad) {
         uint64_t swap_threshold;
 
         assert(ctx);
-        assert(threshold_percent <= 100);
+        assert(threshold_permyriad <= 10000);
 
-        swap_threshold = ctx->swap_total * threshold_percent / ((uint64_t) 100);
+        swap_threshold = ctx->swap_total * threshold_permyriad / (uint64_t) 10000;
         return (ctx->swap_total - ctx->swap_used) < swap_threshold;
 }
 
diff --git a/src/oom/oomd-util.h b/src/oom/oomd-util.h
index bffccf75da..181443ae7a 100644
--- a/src/oom/oomd-util.h
+++ b/src/oom/oomd-util.h
@@ -61,8 +61,8 @@ int oomd_pressure_above(Hashmap *h, usec_t duration, Set **ret);
  * current sum is higher than the last interval's sum (there was some reclaim activity). */
 bool oomd_memory_reclaim(Hashmap *h);
 
-/* Returns true if the amount of swap free is below the percentage of swap specified by `threshold_percent`. */
-bool oomd_swap_free_below(const OomdSystemContext *ctx, uint64_t threshold_percent);
+/* Returns true if the amount of swap free is below the permyriad of swap specified by `threshold_permyriad`. */
+bool oomd_swap_free_below(const OomdSystemContext *ctx, int threshold_permyriad);
 
 /* The compare functions will sort from largest to smallest, putting all the contexts with "avoid" at the end
  * (after the smallest values). */
diff --git a/src/oom/oomd.c b/src/oom/oomd.c
index 2e331e267f..674d53fdcf 100644
--- a/src/oom/oomd.c
+++ b/src/oom/oomd.c
@@ -17,13 +17,13 @@
 #include "signal-util.h"
 
 static bool arg_dry_run = false;
-static int arg_swap_used_limit = -1;
+static int arg_swap_used_limit_permyriad = -1;
 static int arg_mem_pressure_limit_permyriad = -1;
 static usec_t arg_mem_pressure_usec = 0;
 
 static int parse_config(void) {
         static const ConfigTableItem items[] = {
-                { "OOM", "SwapUsedLimitPercent",             config_parse_percent,   0, &arg_swap_used_limit              },
+                { "OOM", "SwapUsedLimit",                    config_parse_permyriad, 0, &arg_swap_used_limit_permyriad    },
                 { "OOM", "DefaultMemoryPressureLimit",       config_parse_permyriad, 0, &arg_mem_pressure_limit_permyriad },
                 { "OOM", "DefaultMemoryPressureDurationSec", config_parse_sec,       0, &arg_mem_pressure_usec            },
                 {}
@@ -159,7 +159,12 @@ static int run(int argc, char *argv[]) {
         if (r < 0)
                 return log_error_errno(r, "Failed to create manager: %m");
 
-        r = manager_start(m, arg_dry_run, arg_swap_used_limit, arg_mem_pressure_limit_permyriad, arg_mem_pressure_usec);
+        r = manager_start(
+                        m,
+                        arg_dry_run,
+                        arg_swap_used_limit_permyriad,
+                        arg_mem_pressure_limit_permyriad,
+                        arg_mem_pressure_usec);
         if (r < 0)
                 return log_error_errno(r, "Failed to start up daemon: %m");
 
diff --git a/src/oom/oomd.conf b/src/oom/oomd.conf
index 59e3416bf3..f1bef9de6f 100644
--- a/src/oom/oomd.conf
+++ b/src/oom/oomd.conf
@@ -13,6 +13,6 @@
 # See oomd.conf(5) for details
 
 [OOM]
-#SwapUsedLimitPercent=90%
+#SwapUsedLimit=90%
 #DefaultMemoryPressureLimit=60%
 #DefaultMemoryPressureDurationSec=30s
diff --git a/src/oom/test-oomd-util.c b/src/oom/test-oomd-util.c
index 49a02f9424..a0e583ac6b 100644
--- a/src/oom/test-oomd-util.c
+++ b/src/oom/test-oomd-util.c
@@ -302,19 +302,19 @@ static void test_oomd_swap_free_below(void) {
                 .swap_total = 20971512 * 1024U,
                 .swap_used = 20971440 * 1024U,
         };
-        assert_se(oomd_swap_free_below(&ctx, 20) == true);
+        assert_se(oomd_swap_free_below(&ctx, 2000) == true);
 
         ctx = (OomdSystemContext) {
                 .swap_total = 20971512 * 1024U,
                 .swap_used = 3310136 * 1024U,
         };
-        assert_se(oomd_swap_free_below(&ctx, 20) == false);
+        assert_se(oomd_swap_free_below(&ctx, 2000) == false);
 
         ctx = (OomdSystemContext) {
                 .swap_total = 0,
                 .swap_used = 0,
         };
-        assert_se(oomd_swap_free_below(&ctx, 20) == false);
+        assert_se(oomd_swap_free_below(&ctx, 2000) == false);
 }
 
 static void test_oomd_sort_cgroups(void) {
diff --git a/src/shared/bus-unit-util.c b/src/shared/bus-unit-util.c
index 548dc57e3c..83130db2fa 100644
--- a/src/shared/bus-unit-util.c
+++ b/src/shared/bus-unit-util.c
@@ -28,6 +28,7 @@
 #include "numa-util.h"
 #include "parse-util.h"
 #include "path-util.h"
+#include "percent-util.h"
 #include "process-util.h"
 #include "rlimit-util.h"
 #if HAVE_SECCOMP
@@ -440,15 +441,12 @@ static int bus_append_cgroup_property(sd_bus_message *m, const char *field, cons
                 return bus_append_string(m, field, eq);
 
         if (STR_IN_SET(field, "ManagedOOMMemoryPressureLimit")) {
-                char *n;
-
                 r = parse_permyriad(eq);
                 if (r < 0)
                         return log_error_errno(r, "Failed to parse %s value: %s", field, eq);
 
-                n = strjoina(field, "Permyriad");
-
-                r = sd_bus_message_append(m, "(sv)", n, "u", (uint32_t) r);
+                /* Pass around scaled to 2^32-1 == 100% */
+                r = sd_bus_message_append(m, "(sv)", field, "u", UINT32_SCALE_FROM_PERMYRIAD(r));
                 if (r < 0)
                         return bus_log_create_error(r);
 
@@ -539,7 +537,7 @@ static int bus_append_cgroup_property(sd_bus_message *m, const char *field, cons
                         return 1;
                 }
 
-                r = parse_permille(eq);
+                r = parse_permyriad(eq);
                 if (r >= 0) {
                         char *n;
 
@@ -548,7 +546,7 @@ static int bus_append_cgroup_property(sd_bus_message *m, const char *field, cons
                          * size can be determined server-side. */
 
                         n = strjoina(field, "Scale");
-                        r = sd_bus_message_append(m, "(sv)", n, "u", (uint32_t) (((uint64_t) r * UINT32_MAX) / 1000U));
+                        r = sd_bus_message_append(m, "(sv)", n, "u", UINT32_SCALE_FROM_PERMYRIAD(r));
                         if (r < 0)
                                 return bus_log_create_error(r);
 
@@ -565,14 +563,14 @@ static int bus_append_cgroup_property(sd_bus_message *m, const char *field, cons
                 if (isempty(eq))
                         r = sd_bus_message_append(m, "(sv)", "CPUQuotaPerSecUSec", "t", USEC_INFINITY);
                 else {
-                        r = parse_permille_unbounded(eq);
+                        r = parse_permyriad_unbounded(eq);
                         if (r == 0)
                                 return log_error_errno(SYNTHETIC_ERRNO(ERANGE),
                                                        "CPU quota too small.");
                         if (r < 0)
                                 return log_error_errno(r, "CPU quota '%s' invalid.", eq);
 
-                        r = sd_bus_message_append(m, "(sv)", "CPUQuotaPerSecUSec", "t", (((uint64_t) r * USEC_PER_SEC) / 1000U));
+                        r = sd_bus_message_append(m, "(sv)", "CPUQuotaPerSecUSec", "t", (((uint64_t) r * USEC_PER_SEC) / 10000U));
                 }
 
                 if (r < 0)
diff --git a/src/shared/conf-parser.c b/src/shared/conf-parser.c
index c3d7e536ec..df6472d4be 100644
--- a/src/shared/conf-parser.c
+++ b/src/shared/conf-parser.c
@@ -22,6 +22,7 @@
 #include "nulstr-util.h"
 #include "parse-util.h"
 #include "path-util.h"
+#include "percent-util.h"
 #include "process-util.h"
 #include "rlimit-util.h"
 #include "sd-id128.h"
diff --git a/src/test/meson.build b/src/test/meson.build
index 5bf1ca3490..c567a4cfcb 100644
--- a/src/test/meson.build
+++ b/src/test/meson.build
@@ -547,6 +547,8 @@ tests += [
 
         [['src/test/test-bus-util.c']],
 
+        [['src/test/test-percent-util.c']],
+
         [['src/test/test-sd-hwdb.c']],
 
         [['src/test/test-sd-path.c']],
diff --git a/src/test/test-parse-util.c b/src/test/test-parse-util.c
index 6e23efe134..756934acad 100644
--- a/src/test/test-parse-util.c
+++ b/src/test/test-parse-util.c
@@ -718,144 +718,6 @@ static void test_safe_atod(void) {
         assert_se(r == -EINVAL);
 }
 
-static void test_parse_percent(void) {
-        assert_se(parse_percent("") == -EINVAL);
-        assert_se(parse_percent("foo") == -EINVAL);
-        assert_se(parse_percent("0") == -EINVAL);
-        assert_se(parse_percent("50") == -EINVAL);
-        assert_se(parse_percent("100") == -EINVAL);
-        assert_se(parse_percent("-1") == -EINVAL);
-        assert_se(parse_percent("0%") == 0);
-        assert_se(parse_percent("55%") == 55);
-        assert_se(parse_percent("100%") == 100);
-        assert_se(parse_percent("-7%") == -ERANGE);
-        assert_se(parse_percent("107%") == -ERANGE);
-        assert_se(parse_percent("%") == -EINVAL);
-        assert_se(parse_percent("%%") == -EINVAL);
-        assert_se(parse_percent("%1") == -EINVAL);
-        assert_se(parse_percent("1%%") == -EINVAL);
-        assert_se(parse_percent("3.2%") == -EINVAL);
-}
-
-static void test_parse_percent_unbounded(void) {
-        assert_se(parse_percent_unbounded("101%") == 101);
-        assert_se(parse_percent_unbounded("400%") == 400);
-}
-
-static void test_parse_permille(void) {
-        assert_se(parse_permille("") == -EINVAL);
-        assert_se(parse_permille("foo") == -EINVAL);
-        assert_se(parse_permille("0") == -EINVAL);
-        assert_se(parse_permille("50") == -EINVAL);
-        assert_se(parse_permille("100") == -EINVAL);
-        assert_se(parse_permille("-1") == -EINVAL);
-
-        assert_se(parse_permille("0‰") == 0);
-        assert_se(parse_permille("555‰") == 555);
-        assert_se(parse_permille("1000‰") == 1000);
-        assert_se(parse_permille("-7‰") == -ERANGE);
-        assert_se(parse_permille("1007‰") == -ERANGE);
-        assert_se(parse_permille("‰") == -EINVAL);
-        assert_se(parse_permille("‰‰") == -EINVAL);
-        assert_se(parse_permille("‰1") == -EINVAL);
-        assert_se(parse_permille("1‰‰") == -EINVAL);
-        assert_se(parse_permille("3.2‰") == -EINVAL);
-
-        assert_se(parse_permille("0%") == 0);
-        assert_se(parse_permille("55%") == 550);
-        assert_se(parse_permille("55.5%") == 555);
-        assert_se(parse_permille("100%") == 1000);
-        assert_se(parse_permille("-7%") == -ERANGE);
-        assert_se(parse_permille("107%") == -ERANGE);
-        assert_se(parse_permille("%") == -EINVAL);
-        assert_se(parse_permille("%%") == -EINVAL);
-        assert_se(parse_permille("%1") == -EINVAL);
-        assert_se(parse_permille("1%%") == -EINVAL);
-        assert_se(parse_permille("3.21%") == -EINVAL);
-}
-
-static void test_parse_permille_unbounded(void) {
-        assert_se(parse_permille_unbounded("1001‰") == 1001);
-        assert_se(parse_permille_unbounded("4000‰") == 4000);
-        assert_se(parse_permille_unbounded("2147483647‰") == 2147483647);
-        assert_se(parse_permille_unbounded("2147483648‰") == -ERANGE);
-        assert_se(parse_permille_unbounded("4294967295‰") == -ERANGE);
-        assert_se(parse_permille_unbounded("4294967296‰") == -ERANGE);
-
-        assert_se(parse_permille_unbounded("101%") == 1010);
-        assert_se(parse_permille_unbounded("400%") == 4000);
-        assert_se(parse_permille_unbounded("214748364.7%") == 2147483647);
-        assert_se(parse_permille_unbounded("214748364.8%") == -ERANGE);
-        assert_se(parse_permille_unbounded("429496729.5%") == -ERANGE);
-        assert_se(parse_permille_unbounded("429496729.6%") == -ERANGE);
-}
-
-static void test_parse_permyriad(void) {
-        assert_se(parse_permyriad("") == -EINVAL);
-        assert_se(parse_permyriad("foo") == -EINVAL);
-        assert_se(parse_permyriad("0") == -EINVAL);
-        assert_se(parse_permyriad("50") == -EINVAL);
-        assert_se(parse_permyriad("100") == -EINVAL);
-        assert_se(parse_permyriad("-1") == -EINVAL);
-
-        assert_se(parse_permyriad("0‱") == 0);
-        assert_se(parse_permyriad("555‱") == 555);
-        assert_se(parse_permyriad("1000‱") == 1000);
-        assert_se(parse_permyriad("-7‱") == -ERANGE);
-        assert_se(parse_permyriad("10007‱") == -ERANGE);
-        assert_se(parse_permyriad("‱") == -EINVAL);
-        assert_se(parse_permyriad("‱‱") == -EINVAL);
-        assert_se(parse_permyriad("‱1") == -EINVAL);
-        assert_se(parse_permyriad("1‱‱") == -EINVAL);
-        assert_se(parse_permyriad("3.2‱") == -EINVAL);
-
-        assert_se(parse_permyriad("0‰") == 0);
-        assert_se(parse_permyriad("555.5‰") == 5555);
-        assert_se(parse_permyriad("1000.0‰") == 10000);
-        assert_se(parse_permyriad("-7‰") == -ERANGE);
-        assert_se(parse_permyriad("1007‰") == -ERANGE);
-        assert_se(parse_permyriad("‰") == -EINVAL);
-        assert_se(parse_permyriad("‰‰") == -EINVAL);
-        assert_se(parse_permyriad("‰1") == -EINVAL);
-        assert_se(parse_permyriad("1‰‰") == -EINVAL);
-        assert_se(parse_permyriad("3.22‰") == -EINVAL);
-
-        assert_se(parse_permyriad("0%") == 0);
-        assert_se(parse_permyriad("55%") == 5500);
-        assert_se(parse_permyriad("55.53%") == 5553);
-        assert_se(parse_permyriad("100%") == 10000);
-        assert_se(parse_permyriad("-7%") == -ERANGE);
-        assert_se(parse_permyriad("107%") == -ERANGE);
-        assert_se(parse_permyriad("%") == -EINVAL);
-        assert_se(parse_permyriad("%%") == -EINVAL);
-        assert_se(parse_permyriad("%1") == -EINVAL);
-        assert_se(parse_permyriad("1%%") == -EINVAL);
-        assert_se(parse_permyriad("3.212%") == -EINVAL);
-}
-
-static void test_parse_permyriad_unbounded(void) {
-        assert_se(parse_permyriad_unbounded("1001‱") == 1001);
-        assert_se(parse_permyriad_unbounded("4000‱") == 4000);
-        assert_se(parse_permyriad_unbounded("2147483647‱") == 2147483647);
-        assert_se(parse_permyriad_unbounded("2147483648‱") == -ERANGE);
-        assert_se(parse_permyriad_unbounded("4294967295‱") == -ERANGE);
-        assert_se(parse_permyriad_unbounded("4294967296‱") == -ERANGE);
-
-        assert_se(parse_permyriad_unbounded("101‰") == 1010);
-        assert_se(parse_permyriad_unbounded("400‰") == 4000);
-        assert_se(parse_permyriad_unbounded("214748364.7‰") == 2147483647);
-        assert_se(parse_permyriad_unbounded("214748364.8‰") == -ERANGE);
-        assert_se(parse_permyriad_unbounded("429496729.5‰") == -ERANGE);
-        assert_se(parse_permyriad_unbounded("429496729.6‰") == -ERANGE);
-
-        assert_se(parse_permyriad_unbounded("99%") == 9900);
-        assert_se(parse_permyriad_unbounded("40%") == 4000);
-        assert_se(parse_permyriad_unbounded("21474836.47%") == 2147483647);
-        assert_se(parse_permyriad_unbounded("21474836.48%") == -ERANGE);
-        assert_se(parse_permyriad_unbounded("42949672.95%") == -ERANGE);
-        assert_se(parse_permyriad_unbounded("42949672.96%") == -ERANGE);
-}
-
 static void test_parse_nice(void) {
         int n;
 
@@ -1049,12 +911,6 @@ int main(int argc, char *argv[]) {
         test_safe_atoi64();
         test_safe_atoux64();
         test_safe_atod();
-        test_parse_percent();
-        test_parse_percent_unbounded();
-        test_parse_permille();
-        test_parse_permille_unbounded();
-        test_parse_permyriad();
-        test_parse_permyriad_unbounded();
         test_parse_nice();
         test_parse_dev();
         test_parse_errno();
diff --git a/src/test/test-percent-util.c b/src/test/test-percent-util.c
new file mode 100644
index 0000000000..b8801438a7
--- /dev/null
+++ b/src/test/test-percent-util.c
@@ -0,0 +1,211 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include "percent-util.h"
+#include "tests.h"
+#include "time-util.h"
+
+static void test_parse_percent(void) {
+        assert_se(parse_percent("") == -EINVAL);
+        assert_se(parse_percent("foo") == -EINVAL);
+        assert_se(parse_percent("0") == -EINVAL);
+        assert_se(parse_percent("0.1") == -EINVAL);
+        assert_se(parse_percent("50") == -EINVAL);
+        assert_se(parse_percent("100") == -EINVAL);
+        assert_se(parse_percent("-1") == -EINVAL);
+        assert_se(parse_percent("0%") == 0);
+        assert_se(parse_percent("55%") == 55);
+        assert_se(parse_percent("100%") == 100);
+        assert_se(parse_percent("-7%") == -ERANGE);
+        assert_se(parse_percent("107%") == -ERANGE);
+        assert_se(parse_percent("%") == -EINVAL);
+        assert_se(parse_percent("%%") == -EINVAL);
+        assert_se(parse_percent("%1") == -EINVAL);
+        assert_se(parse_percent("1%%") == -EINVAL);
+        assert_se(parse_percent("3.2%") == -EINVAL);
+}
+
+static void test_parse_percent_unbounded(void) {
+        assert_se(parse_percent_unbounded("101%") == 101);
+        assert_se(parse_percent_unbounded("400%") == 400);
+}
+
+static void test_parse_permille(void) {
+        assert_se(parse_permille("") == -EINVAL);
+        assert_se(parse_permille("foo") == -EINVAL);
+        assert_se(parse_permille("0") == -EINVAL);
+        assert_se(parse_permille("50") == -EINVAL);
+        assert_se(parse_permille("100") == -EINVAL);
+        assert_se(parse_permille("-1") == -EINVAL);
+        assert_se(parse_permille("0.1") == -EINVAL);
+        assert_se(parse_permille("5%") == 50);
+        assert_se(parse_permille("5.5%") == 55);
+        assert_se(parse_permille("5.12%") == -EINVAL);
+
+        assert_se(parse_permille("0‰") == 0);
+        assert_se(parse_permille("555‰") == 555);
+        assert_se(parse_permille("1000‰") == 1000);
+        assert_se(parse_permille("-7‰") == -ERANGE);
+        assert_se(parse_permille("1007‰") == -ERANGE);
+        assert_se(parse_permille("‰") == -EINVAL);
+        assert_se(parse_permille("‰‰") == -EINVAL);
+        assert_se(parse_permille("‰1") == -EINVAL);
+        assert_se(parse_permille("1‰‰") == -EINVAL);
+        assert_se(parse_permille("3.2‰") == -EINVAL);
+        assert_se(parse_permille("0.1‰") == -EINVAL);
+
+        assert_se(parse_permille("0%") == 0);
+        assert_se(parse_permille("55%") == 550);
+        assert_se(parse_permille("55.5%") == 555);
+        assert_se(parse_permille("100%") == 1000);
+        assert_se(parse_permille("-7%") == -ERANGE);
+        assert_se(parse_permille("107%") == -ERANGE);
+        assert_se(parse_permille("%") == -EINVAL);
+        assert_se(parse_permille("%%") == -EINVAL);
+        assert_se(parse_permille("%1") == -EINVAL);
+        assert_se(parse_permille("1%%") == -EINVAL);
+        assert_se(parse_permille("3.21%") == -EINVAL);
+        assert_se(parse_permille("0.1%") == 1);
+}
+
+static void test_parse_permille_unbounded(void) {
+        assert_se(parse_permille_unbounded("1001‰") == 1001);
+        assert_se(parse_permille_unbounded("4000‰") == 4000);
+        assert_se(parse_permille_unbounded("2147483647‰") == 2147483647);
+        assert_se(parse_permille_unbounded("2147483648‰") == -ERANGE);
+        assert_se(parse_permille_unbounded("4294967295‰") == -ERANGE);
+        assert_se(parse_permille_unbounded("4294967296‰") == -ERANGE);
+
+        assert_se(parse_permille_unbounded("101%") == 1010);
+        assert_se(parse_permille_unbounded("400%") == 4000);
+        assert_se(parse_permille_unbounded("214748364.7%") == 2147483647);
+        assert_se(parse_permille_unbounded("214748364.8%") == -ERANGE);
+        assert_se(parse_permille_unbounded("429496729.5%") == -ERANGE);
+        assert_se(parse_permille_unbounded("429496729.6%") == -ERANGE);
+}
+
+static void test_parse_permyriad(void) {
+        assert_se(parse_permyriad("") == -EINVAL);
+        assert_se(parse_permyriad("foo") == -EINVAL);
+        assert_se(parse_permyriad("0") == -EINVAL);
+        assert_se(parse_permyriad("50") == -EINVAL);
+        assert_se(parse_permyriad("100") == -EINVAL);
+        assert_se(parse_permyriad("-1") == -EINVAL);
+
+        assert_se(parse_permyriad("0‱") == 0);
+        assert_se(parse_permyriad("555‱") == 555);
+        assert_se(parse_permyriad("1000‱") == 1000);
+        assert_se(parse_permyriad("-7‱") == -ERANGE);
+        assert_se(parse_permyriad("10007‱") == -ERANGE);
+        assert_se(parse_permyriad("‱") == -EINVAL);
+        assert_se(parse_permyriad("‱‱") == -EINVAL);
+        assert_se(parse_permyriad("‱1") == -EINVAL);
+        assert_se(parse_permyriad("1‱‱") == -EINVAL);
+        assert_se(parse_permyriad("3.2‱") == -EINVAL);
+
+        assert_se(parse_permyriad("0‰") == 0);
+        assert_se(parse_permyriad("555.5‰") == 5555);
+        assert_se(parse_permyriad("1000.0‰") == 10000);
+        assert_se(parse_permyriad("-7‰") == -ERANGE);
+        assert_se(parse_permyriad("1007‰") == -ERANGE);
+        assert_se(parse_permyriad("‰") == -EINVAL);
+        assert_se(parse_permyriad("‰‰") == -EINVAL);
+        assert_se(parse_permyriad("‰1") == -EINVAL);
+        assert_se(parse_permyriad("1‰‰") == -EINVAL);
+        assert_se(parse_permyriad("3.22‰") == -EINVAL);
+
+        assert_se(parse_permyriad("0%") == 0);
+        assert_se(parse_permyriad("55%") == 5500);
+        assert_se(parse_permyriad("55.5%") == 5550);
+        assert_se(parse_permyriad("55.50%") == 5550);
+        assert_se(parse_permyriad("55.53%") == 5553);
+        assert_se(parse_permyriad("100%") == 10000);
+        assert_se(parse_permyriad("-7%") == -ERANGE);
+        assert_se(parse_permyriad("107%") == -ERANGE);
+        assert_se(parse_permyriad("%") == -EINVAL);
+        assert_se(parse_permyriad("%%") == -EINVAL);
+        assert_se(parse_permyriad("%1") == -EINVAL);
+        assert_se(parse_permyriad("1%%") == -EINVAL);
+        assert_se(parse_permyriad("3.212%") == -EINVAL);
+}
+
+static void test_parse_permyriad_unbounded(void) {
+        assert_se(parse_permyriad_unbounded("1001‱") == 1001);
+        assert_se(parse_permyriad_unbounded("4000‱") == 4000);
+        assert_se(parse_permyriad_unbounded("2147483647‱") == 2147483647);
+        assert_se(parse_permyriad_unbounded("2147483648‱") == -ERANGE);
+        assert_se(parse_permyriad_unbounded("4294967295‱") == -ERANGE);
+        assert_se(parse_permyriad_unbounded("4294967296‱") == -ERANGE);
+
+        assert_se(parse_permyriad_unbounded("101‰") == 1010);
+        assert_se(parse_permyriad_unbounded("400‰") == 4000);
+        assert_se(parse_permyriad_unbounded("214748364.7‰") == 2147483647);
+        assert_se(parse_permyriad_unbounded("214748364.8‰") == -ERANGE);
+        assert_se(parse_permyriad_unbounded("429496729.5‰") == -ERANGE);
+        assert_se(parse_permyriad_unbounded("429496729.6‰") == -ERANGE);
+
+        assert_se(parse_permyriad_unbounded("99%") == 9900);
+        assert_se(parse_permyriad_unbounded("40%") == 4000);
+        assert_se(parse_permyriad_unbounded("21474836.47%") == 2147483647);
+        assert_se(parse_permyriad_unbounded("21474836.48%") == -ERANGE);
+        assert_se(parse_permyriad_unbounded("42949672.95%") == -ERANGE);
+        assert_se(parse_permyriad_unbounded("42949672.96%") == -ERANGE);
+}
+
+static void test_scale(void) {
+        /* Check some fixed values */
+        assert_se(UINT32_SCALE_FROM_PERCENT(0) == 0);
+        assert_se(UINT32_SCALE_FROM_PERCENT(50) == UINT32_MAX/2+1);
+        assert_se(UINT32_SCALE_FROM_PERCENT(100) == UINT32_MAX);
+
+        assert_se(UINT32_SCALE_FROM_PERMILLE(0) == 0);
+        assert_se(UINT32_SCALE_FROM_PERMILLE(500) == UINT32_MAX/2+1);
+        assert_se(UINT32_SCALE_FROM_PERMILLE(1000) == UINT32_MAX);
+
+        assert_se(UINT32_SCALE_FROM_PERMYRIAD(0) == 0);
+        assert_se(UINT32_SCALE_FROM_PERMYRIAD(5000) == UINT32_MAX/2+1);
+        assert_se(UINT32_SCALE_FROM_PERMYRIAD(10000) == UINT32_MAX);
+
+        /* Make sure there's no numeric noise on the 0%…100% scale when converting from percent and back. */
+        for (int percent = 0; percent <= 100; percent++) {
+                log_debug("%i%% → %" PRIu32 " → %i%%",
+                          percent,
+                          UINT32_SCALE_FROM_PERCENT(percent),
+                          UINT32_SCALE_TO_PERCENT(UINT32_SCALE_FROM_PERCENT(percent)));
+
+                assert_se(UINT32_SCALE_TO_PERCENT(UINT32_SCALE_FROM_PERCENT(percent)) == percent);
+        }
+
+        /* Make sure there's no numeric noise on the 0‰…1000‰ scale when converting from permille and back. */
+        for (int permille = 0; permille <= 1000; permille++) {
+                log_debug("%i‰ → %" PRIu32 " → %i‰",
+                          permille,
+                          UINT32_SCALE_FROM_PERMILLE(permille),
+                          UINT32_SCALE_TO_PERMILLE(UINT32_SCALE_FROM_PERMILLE(permille)));
+
+                assert_se(UINT32_SCALE_TO_PERMILLE(UINT32_SCALE_FROM_PERMILLE(permille)) == permille);
+        }
+
+        /* Make sure there's no numeric noise on the 0‱…10000‱ scale when converting from permyriad and back. */
+        for (int permyriad = 0; permyriad <= 10000; permyriad++) {
+                log_debug("%i‱ → %" PRIu32 " → %i‱",
+                          permyriad,
+                          UINT32_SCALE_FROM_PERMYRIAD(permyriad),
+                          UINT32_SCALE_TO_PERMYRIAD(UINT32_SCALE_FROM_PERMYRIAD(permyriad)));
+
+                assert_se(UINT32_SCALE_TO_PERMYRIAD(UINT32_SCALE_FROM_PERMYRIAD(permyriad)) == permyriad);
+        }
+}
+
+int main(int argc, char *argv[]) {
+        test_setup_logging(LOG_DEBUG);
+
+        test_parse_percent();
+        test_parse_percent_unbounded();
+        test_parse_permille();
+        test_parse_permille_unbounded();
+        test_parse_permyriad();
+        test_parse_permyriad_unbounded();
+        test_scale();
+
+        return 0;
+}