core/cgroup: fold unit_get_current_memory() into generic memory accounting helper

diff --git a/src/core/cgroup.c b/src/core/cgroup.c
index afb53f26c3287c7deae314bf77824b12f09fa906..fb913f7c90e551f45f6770e606912d2ba2ea121e 100644 (file)
--- a/src/core/cgroup.c
+++ b/src/core/cgroup.c
@@ -4505,7 +4505,7 @@ int unit_get_memory_available(Unit *u, uint64_t *ret) {
                 if (!crt || !crt->cgroup_path)
                         continue;
 
-                (void) unit_get_memory_current(u, &current);
+                (void) unit_get_memory_accounting(u, CGROUP_MEMORY_CURRENT, &current);
                 /* in case of error, previous current propagates as lower bound */
 
                 if (unit_has_name(u, SPECIAL_ROOT_SLICE))
@@ -4523,38 +4523,10 @@ int unit_get_memory_available(Unit *u, uint64_t *ret) {
         return 0;
 }
 
-int unit_get_memory_current(Unit *u, uint64_t *ret) {
-        int r;
-
-        // FIXME: Merge this into unit_get_memory_accounting after support for cgroup v1 is dropped
-
-        assert(u);
-        assert(ret);
-
-        if (!UNIT_CGROUP_BOOL(u, memory_accounting))
-                return -ENODATA;
-
-        CGroupRuntime *crt = unit_get_cgroup_runtime(u);
-        if (!crt || !crt->cgroup_path)
-                return -ENODATA;
-
-        /* The root cgroup doesn't expose this information, let's get it from /proc instead */
-        if (unit_has_host_root_cgroup(u))
-                return procfs_memory_get_used(ret);
-
-        if ((crt->cgroup_realized_mask & CGROUP_MASK_MEMORY) == 0)
-                return -ENODATA;
-
-        r = cg_all_unified();
-        if (r < 0)
-                return r;
-
-        return cg_get_attribute_as_uint64("memory", crt->cgroup_path, r > 0 ? "memory.current" : "memory.usage_in_bytes", ret);
-}
-
 int unit_get_memory_accounting(Unit *u, CGroupMemoryAccountingMetric metric, uint64_t *ret) {
 
         static const char* const attributes_table[_CGROUP_MEMORY_ACCOUNTING_METRIC_MAX] = {
+                [CGROUP_MEMORY_CURRENT]       = "memory.current",
                 [CGROUP_MEMORY_PEAK]          = "memory.peak",
                 [CGROUP_MEMORY_SWAP_CURRENT]  = "memory.swap.current",
                 [CGROUP_MEMORY_SWAP_PEAK]     = "memory.swap.peak",
@@ -4573,8 +4545,13 @@ int unit_get_memory_accounting(Unit *u, CGroupMemoryAccountingMetric metric, uin
                 return -ENODATA;
 
         /* The root cgroup doesn't expose this information. */
-        if (unit_has_host_root_cgroup(u))
+        if (unit_has_host_root_cgroup(u)) {
+                /* System-wide memory usage can be acquired from /proc/ */
+                if (metric == CGROUP_MEMORY_CURRENT)
+                        return procfs_memory_get_used(ret);
+
                 return -ENODATA;
+        }
 
         CGroupRuntime *crt = unit_get_cgroup_runtime(u);
         if (!crt)
@@ -4586,12 +4563,6 @@ int unit_get_memory_accounting(Unit *u, CGroupMemoryAccountingMetric metric, uin
         if (!FLAGS_SET(crt->cgroup_realized_mask, CGROUP_MASK_MEMORY))
                 return -ENODATA;
 
-        r = cg_all_unified();
-        if (r < 0)
-                return r;
-        if (r == 0)
-                return -ENODATA;
-
         r = cg_get_attribute_as_uint64("memory", crt->cgroup_path, attributes_table[metric], &bytes);
         if (r < 0 && r != -ENODATA)
                 return r;
@@ -5686,6 +5657,7 @@ static const char* const cgroup_io_accounting_metric_table[_CGROUP_IO_ACCOUNTING
 DEFINE_STRING_TABLE_LOOKUP(cgroup_io_accounting_metric, CGroupIOAccountingMetric);
 
 static const char* const cgroup_memory_accounting_metric_table[_CGROUP_MEMORY_ACCOUNTING_METRIC_MAX] = {
+        [CGROUP_MEMORY_CURRENT]       = "MemoryCurrent",
         [CGROUP_MEMORY_PEAK]          = "MemoryPeak",
         [CGROUP_MEMORY_SWAP_CURRENT]  = "MemorySwapCurrent",
         [CGROUP_MEMORY_SWAP_PEAK]     = "MemorySwapPeak",

diff --git a/src/core/cgroup.h b/src/core/cgroup.h
index b25cdad7d866dc076f8df4af5a47ede003b317ae..7b3fbc3b1504c2305755eca12c09c62aa55dac88 100644 (file)
--- a/src/core/cgroup.h
+++ b/src/core/cgroup.h
@@ -280,6 +280,7 @@ typedef enum CGroupMemoryAccountingMetric {
         _CGROUP_MEMORY_ACCOUNTING_METRIC_CACHED_LAST = CGROUP_MEMORY_SWAP_PEAK,
 
         /* These attributes are transient, so no need for caching. */
+        CGROUP_MEMORY_CURRENT,
         CGROUP_MEMORY_SWAP_CURRENT,
         CGROUP_MEMORY_ZSWAP_CURRENT,
 
@@ -478,7 +479,6 @@ int unit_watch_all_pids(Unit *u);
 int unit_synthesize_cgroup_empty_event(Unit *u);
 
 int unit_get_memory_available(Unit *u, uint64_t *ret);
-int unit_get_memory_current(Unit *u, uint64_t *ret);
 int unit_get_memory_accounting(Unit *u, CGroupMemoryAccountingMetric metric, uint64_t *ret);
 int unit_get_tasks_current(Unit *u, uint64_t *ret);
 int unit_get_cpu_usage(Unit *u, nsec_t *ret);

diff --git a/src/core/dbus-unit.c b/src/core/dbus-unit.c
index 68cfed9444f07deec7050c9bc86a70b14738b48a..e9a2a4a4c092898bab70b1293d6887d05bff7ab2 100644 (file)
--- a/src/core/dbus-unit.c
+++ b/src/core/dbus-unit.c
@@ -1052,29 +1052,6 @@ static int property_get_slice(
         return sd_bus_message_append(reply, "s", unit_slice_name(u));
 }
 
-static int property_get_current_memory(
-                sd_bus *bus,
-                const char *path,
-                const char *interface,
-                const char *property,
-                sd_bus_message *reply,
-                void *userdata,
-                sd_bus_error *error) {
-
-        uint64_t sz = UINT64_MAX;
-        Unit *u = ASSERT_PTR(userdata);
-        int r;
-
-        assert(bus);
-        assert(reply);
-
-        r = unit_get_memory_current(u, &sz);
-        if (r < 0 && r != -ENODATA)
-                log_unit_warning_errno(u, r, "Failed to get current memory usage from cgroup: %m");
-
-        return sd_bus_message_append(reply, "t", sz);
-}
-
 static int property_get_available_memory(
                 sd_bus *bus,
                 const char *path,
@@ -1652,7 +1629,7 @@ const sd_bus_vtable bus_unit_cgroup_vtable[] = {
         SD_BUS_PROPERTY("Slice", "s", property_get_slice, 0, 0),
         SD_BUS_PROPERTY("ControlGroup", "s", property_get_cgroup, 0, 0),
         SD_BUS_PROPERTY("ControlGroupId", "t", property_get_cgroup_id, 0, 0),
-        SD_BUS_PROPERTY("MemoryCurrent", "t", property_get_current_memory, 0, 0),
+        SD_BUS_PROPERTY("MemoryCurrent", "t", property_get_memory_accounting, 0, 0),
         SD_BUS_PROPERTY("MemoryPeak", "t", property_get_memory_accounting, 0, 0),
         SD_BUS_PROPERTY("MemorySwapCurrent", "t", property_get_memory_accounting, 0, 0),
         SD_BUS_PROPERTY("MemorySwapPeak", "t", property_get_memory_accounting, 0, 0),