X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fcore%2Fcgroup.c;h=10fdcc9984e39f4a5171c77d68c750d7b7d3d490;hp=0951a09964358b7157a046cf7b1d36832b4aa9b3;hb=615938651d3a4fd9253b08da00db22d451a8cef8;hpb=a931ad47a8623163a29d898224d8a8c1177ffdaf

diff --git a/src/core/cgroup.c b/src/core/cgroup.c
index 0951a0996..10fdcc998 100644
--- a/src/core/cgroup.c
+++ b/src/core/cgroup.c
@@ -153,10 +153,8 @@ static int lookup_blkio_device(const char *p, dev_t *dev) {
         assert(dev);
 
         r = stat(p, &st);
-        if (r < 0) {
-                log_warning("Couldn't stat device %s: %m", p);
-                return -errno;
-        }
+        if (r < 0)
+                return log_warning_errno(errno, "Couldn't stat device %s: %m", p);
 
         if (S_ISBLK(st.st_mode))
                 *dev = st.st_rdev;
@@ -202,7 +200,8 @@ static int whitelist_device(const char *path, const char *node, const char *acc)
 
         r = cg_set_attribute("devices", path, "devices.allow", buf);
         if (r < 0)
-                log_full(r == -ENOENT ? LOG_DEBUG : LOG_WARNING, "Failed to set devices.allow on %s: %s", path, strerror(-r));
+                log_full_errno(IN_SET(r, -ENOENT, -EROFS, -EINVAL) ? LOG_DEBUG : LOG_WARNING, r,
+                               "Failed to set devices.allow on %s: %m", path);
 
         return r;
 }
@@ -218,10 +217,8 @@ static int whitelist_major(const char *path, const char *name, char type, const
         assert(type == 'b' || type == 'c');
 
         f = fopen("/proc/devices", "re");
-        if (!f) {
-                log_warning("Cannot open /proc/devices to resolve %s (%c): %m", name, type);
-                return -errno;
-        }
+        if (!f)
+                return log_warning_errno(errno, "Cannot open /proc/devices to resolve %s (%c): %m", name, type);
 
         FOREACH_LINE(line, f, goto fail) {
                 char buf[2+DECIMAL_STR_MAX(unsigned)+3+4], *p, *w;
@@ -274,13 +271,14 @@ static int whitelist_major(const char *path, const char *name, char type, const
 
                 r = cg_set_attribute("devices", path, "devices.allow", buf);
                 if (r < 0)
-                        log_full(r == -ENOENT ? LOG_DEBUG : LOG_WARNING, "Failed to set devices.allow on %s: %s", path, strerror(-r));
+                        log_full_errno(IN_SET(r, -ENOENT, -EROFS, -EINVAL) ? LOG_DEBUG : LOG_WARNING, r,
+                                       "Failed to set devices.allow on %s: %m", path);
         }
 
         return 0;
 
 fail:
-        log_warning("Failed to read /proc/devices: %m");
+        log_warning_errno(errno, "Failed to read /proc/devices: %m");
         return -errno;
 }
 
@@ -294,9 +292,16 @@ void cgroup_context_apply(CGroupContext *c, CGroupControllerMask mask, const cha
         if (mask == 0)
                 return;
 
-        /* Some cgroup attributes are not support on the root cgroup,
+        /* Some cgroup attributes are not supported on the root cgroup,
          * hence silently ignore */
         is_root = isempty(path) || path_equal(path, "/");
+        if (is_root)
+                /* Make sure we don't try to display messages with an empty path. */
+                path = "/";
+
+        /* We generally ignore errors caused by read-only mounted
+         * cgroup trees (assuming we are running in a container then),
+         * and missing cgroups, i.e. EROFS and ENOENT. */
 
         if ((mask & CGROUP_CPU) && !is_root) {
                 char buf[MAX(DECIMAL_STR_MAX(unsigned long), DECIMAL_STR_MAX(usec_t)) + 1];
@@ -306,12 +311,14 @@ void cgroup_context_apply(CGroupContext *c, CGroupControllerMask mask, const cha
                         c->cpu_shares != (unsigned long) -1 ? c->cpu_shares : 1024);
                 r = cg_set_attribute("cpu", path, "cpu.shares", buf);
                 if (r < 0)
-                        log_full(r == -ENOENT ? LOG_DEBUG : LOG_WARNING, "Failed to set cpu.shares on %s: %s", path, strerror(-r));
+                        log_full_errno(IN_SET(r, -ENOENT, -EROFS) ? LOG_DEBUG : LOG_WARNING, r,
+                                       "Failed to set cpu.shares on %s: %m", path);
 
                 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_full(r == -ENOENT ? LOG_DEBUG : LOG_WARNING, "Failed to set cpu.cfs_period_us on %s: %s", path, strerror(-r));
+                        log_full_errno(IN_SET(r, -ENOENT, -EROFS) ? LOG_DEBUG : LOG_WARNING, r,
+                                       "Failed to set cpu.cfs_period_us on %s: %m", path);
 
                 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);
@@ -319,7 +326,8 @@ void cgroup_context_apply(CGroupContext *c, CGroupControllerMask mask, const cha
                 } else
                         r = cg_set_attribute("cpu", path, "cpu.cfs_quota_us", "-1");
                 if (r < 0)
-                        log_full(r == -ENOENT ? LOG_DEBUG : LOG_WARNING, "Failed to set cpu.cfs_quota_us on %s: %s", path, strerror(-r));
+                        log_full_errno(IN_SET(r, -ENOENT, -EROFS) ? LOG_DEBUG : LOG_WARNING, r,
+                                       "Failed to set cpu.cfs_quota_us on %s: %m", path);
         }
 
         if (mask & CGROUP_BLKIO) {
@@ -334,7 +342,8 @@ void cgroup_context_apply(CGroupContext *c, CGroupControllerMask mask, const cha
                                 c->blockio_weight != (unsigned long) -1 ? c->blockio_weight : 1000);
                         r = cg_set_attribute("blkio", path, "blkio.weight", buf);
                         if (r < 0)
-                                log_full(r == -ENOENT ? LOG_DEBUG : LOG_WARNING, "Failed to set blkio.weight on %s: %s", path, strerror(-r));
+                                log_full_errno(IN_SET(r, -ENOENT, -EROFS) ? LOG_DEBUG : LOG_WARNING, r,
+                                               "Failed to set blkio.weight on %s: %m", path);
 
                         /* FIXME: no way to reset this list */
                         LIST_FOREACH(device_weights, w, c->blockio_device_weights) {
@@ -347,7 +356,8 @@ void cgroup_context_apply(CGroupContext *c, CGroupControllerMask mask, const cha
                                 sprintf(buf, "%u:%u %lu", major(dev), minor(dev), w->weight);
                                 r = cg_set_attribute("blkio", path, "blkio.weight_device", buf);
                                 if (r < 0)
-                                        log_full(r == -ENOENT ? LOG_DEBUG : LOG_WARNING, "Failed to set blkio.weight_device on %s: %s", path, strerror(-r));
+                                        log_full_errno(IN_SET(r, -ENOENT, -EROFS) ? LOG_DEBUG : LOG_WARNING, r,
+                                                       "Failed to set blkio.weight_device on %s: %m", path);
                         }
                 }
 
@@ -365,11 +375,12 @@ void cgroup_context_apply(CGroupContext *c, CGroupControllerMask mask, const cha
                         sprintf(buf, "%u:%u %" PRIu64 "\n", major(dev), minor(dev), b->bandwidth);
                         r = cg_set_attribute("blkio", path, a, buf);
                         if (r < 0)
-                                log_full(r == -ENOENT ? LOG_DEBUG : LOG_WARNING, "Failed to set %s on %s: %s", a, path, strerror(-r));
+                                log_full_errno(IN_SET(r, -ENOENT, -EROFS) ? LOG_DEBUG : LOG_WARNING, r,
+                                               "Failed to set %s on %s: %m", a, path);
                 }
         }
 
-        if (mask & CGROUP_MEMORY) {
+        if ((mask & CGROUP_MEMORY) && !is_root) {
                 if (c->memory_limit != (uint64_t) -1) {
                         char buf[DECIMAL_STR_MAX(uint64_t) + 1];
 
@@ -379,18 +390,24 @@ void cgroup_context_apply(CGroupContext *c, CGroupControllerMask mask, const cha
                         r = cg_set_attribute("memory", path, "memory.limit_in_bytes", "-1");
 
                 if (r < 0)
-                        log_full(r == -ENOENT ? LOG_DEBUG : LOG_WARNING, "Failed to set memory.limit_in_bytes on %s: %s", path, strerror(-r));
+                        log_full_errno(IN_SET(r, -ENOENT, -EROFS) ? LOG_DEBUG : LOG_WARNING, r,
+                                       "Failed to set memory.limit_in_bytes on %s: %m", path);
         }
 
         if ((mask & CGROUP_DEVICE) && !is_root) {
                 CGroupDeviceAllow *a;
 
+                /* Changing the devices list of a populated cgroup
+                 * might result in EINVAL, hence ignore EINVAL
+                 * here. */
+
                 if (c->device_allow || c->device_policy != CGROUP_AUTO)
                         r = cg_set_attribute("devices", path, "devices.deny", "a");
                 else
                         r = cg_set_attribute("devices", path, "devices.allow", "a");
                 if (r < 0)
-                        log_full(r == -ENOENT ? LOG_DEBUG : LOG_WARNING, "Failed to reset devices.list on %s: %s", path, strerror(-r));
+                        log_full_errno(IN_SET(r, -ENOENT, -EROFS, -EINVAL) ? LOG_DEBUG : LOG_WARNING, r,
+                                       "Failed to reset devices.list on %s: %m", path);
 
                 if (c->device_policy == CGROUP_CLOSED ||
                     (c->device_policy == CGROUP_AUTO && c->device_allow)) {
@@ -609,40 +626,66 @@ static const char *migrate_callback(CGroupControllerMask mask, void *userdata) {
 }
 
 static int unit_create_cgroups(Unit *u, CGroupControllerMask mask) {
-        _cleanup_free_ char *path = NULL;
+        CGroupContext *c;
         int r;
 
         assert(u);
 
-        path = unit_default_cgroup_path(u);
-        if (!path)
-                return log_oom();
+        c = unit_get_cgroup_context(u);
+        if (!c)
+                return 0;
 
-        r = hashmap_put(u->manager->cgroup_unit, path, u);
-        if (r < 0) {
-                log_error(r == -EEXIST ? "cgroup %s exists already: %s" : "hashmap_put failed for %s: %s", path, strerror(-r));
-                return r;
-        }
-        if (r > 0) {
-                u->cgroup_path = path;
-                path = NULL;
+        if (!u->cgroup_path) {
+                _cleanup_free_ char *path = NULL;
+
+                path = unit_default_cgroup_path(u);
+                if (!path)
+                        return log_oom();
+
+                r = hashmap_put(u->manager->cgroup_unit, path, u);
+                if (r < 0) {
+                        log_error(r == -EEXIST ? "cgroup %s exists already: %s" : "hashmap_put failed for %s: %s", path, strerror(-r));
+                        return r;
+                }
+                if (r > 0) {
+                        u->cgroup_path = path;
+                        path = NULL;
+                }
         }
 
         /* First, create our own group */
         r = cg_create_everywhere(u->manager->cgroup_supported, mask, u->cgroup_path);
-        if (r < 0) {
-                log_error("Failed to create cgroup %s: %s", u->cgroup_path, strerror(-r));
-                return r;
-        }
+        if (r < 0)
+                return log_error_errno(r, "Failed to create cgroup %s: %m", u->cgroup_path);
 
         /* Keep track that this is now realized */
         u->cgroup_realized = true;
         u->cgroup_realized_mask = mask;
 
-        /* Then, possibly move things over */
-        r = cg_migrate_everywhere(u->manager->cgroup_supported, u->cgroup_path, u->cgroup_path, migrate_callback, u);
+        if (u->type != UNIT_SLICE && !c->delegate) {
+
+                /* Then, possibly move things over, but not if
+                 * subgroups may contain processes, which is the case
+                 * for slice and delegation units. */
+                r = cg_migrate_everywhere(u->manager->cgroup_supported, u->cgroup_path, u->cgroup_path, migrate_callback, u);
+                if (r < 0)
+                        log_warning_errno(r, "Failed to migrate cgroup from to %s: %m", u->cgroup_path);
+        }
+
+        return 0;
+}
+
+int unit_attach_pids_to_cgroup(Unit *u) {
+        int r;
+        assert(u);
+
+        r = unit_realize_cgroup(u);
         if (r < 0)
-                log_warning("Failed to migrate cgroup from to %s: %s", u->cgroup_path, strerror(-r));
+                return r;
+
+        r = cg_attach_many_everywhere(u->manager->cgroup_supported, u->cgroup_path, u->pids, migrate_callback, u);
+        if (r < 0)
+                return r;
 
         return 0;
 }
@@ -715,7 +758,7 @@ unsigned manager_dispatch_cgroup_queue(Manager *m) {
 
                 r = unit_realize_cgroup_now(i, state);
                 if (r < 0)
-                        log_warning("Failed to realize cgroups for queued unit %s: %s", i->id, strerror(-r));
+                        log_warning_errno(r, "Failed to realize cgroups for queued unit %s: %m", i->id);
 
                 n++;
         }
@@ -788,7 +831,7 @@ int unit_realize_cgroup(Unit *u) {
         return unit_realize_cgroup_now(u, manager_state(u->manager));
 }
 
-void unit_destroy_cgroup(Unit *u) {
+void unit_destroy_cgroup_if_empty(Unit *u) {
         int r;
 
         assert(u);
@@ -797,8 +840,10 @@ void unit_destroy_cgroup(Unit *u) {
                 return;
 
         r = cg_trim_everywhere(u->manager->cgroup_supported, u->cgroup_path, !unit_has_name(u, SPECIAL_ROOT_SLICE));
-        if (r < 0)
-                log_debug("Failed to destroy cgroup %s: %s", u->cgroup_path, strerror(-r));
+        if (r < 0) {
+                log_debug_errno(r, "Failed to destroy cgroup %s: %m", u->cgroup_path);
+                return;
+        }
 
         hashmap_remove(u->manager->cgroup_unit, u->cgroup_path);
 
@@ -806,7 +851,6 @@ void unit_destroy_cgroup(Unit *u) {
         u->cgroup_path = NULL;
         u->cgroup_realized = false;
         u->cgroup_realized_mask = 0;
-
 }
 
 pid_t unit_search_main_pid(Unit *u) {
@@ -857,10 +901,8 @@ int manager_setup_cgroup(Manager *m) {
         m->cgroup_root = NULL;
 
         r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, 0, &m->cgroup_root);
-        if (r < 0) {
-                log_error("Cannot determine cgroup we are running in: %s", strerror(-r));
-                return r;
-        }
+        if (r < 0)
+                return log_error_errno(r, "Cannot determine cgroup we are running in: %m");
 
         /* LEGACY: Already in /system.slice? If so, let's cut this
          * off. This is to support live upgrades from older systemd
@@ -883,10 +925,8 @@ int manager_setup_cgroup(Manager *m) {
 
         /* 2. Show data */
         r = cg_get_path(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_root, NULL, &path);
-        if (r < 0) {
-                log_error("Cannot find cgroup mount point: %s", strerror(-r));
-                return r;
-        }
+        if (r < 0)
+                return log_error_errno(r, "Cannot find cgroup mount point: %m");
 
         log_debug("Using cgroup controller " SYSTEMD_CGROUP_CONTROLLER ". File system hierarchy is at %s.", path);
         if (!m->test_run) {
@@ -895,7 +935,7 @@ int manager_setup_cgroup(Manager *m) {
                 if (m->running_as == SYSTEMD_SYSTEM) {
                         r = cg_install_release_agent(SYSTEMD_CGROUP_CONTROLLER, SYSTEMD_CGROUP_AGENT_PATH);
                         if (r < 0)
-                                log_warning("Failed to install release agent, ignoring: %s", strerror(-r));
+                                log_warning_errno(r, "Failed to install release agent, ignoring: %m");
                         else if (r > 0)
                                 log_debug("Installed release agent.");
                         else
@@ -904,21 +944,17 @@ int manager_setup_cgroup(Manager *m) {
 
                 /* 4. Make sure we are in the root cgroup */
                 r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_root, 0);
-                if (r < 0) {
-                        log_error("Failed to create root cgroup hierarchy: %s", strerror(-r));
-                        return r;
-                }
+                if (r < 0)
+                        return log_error_errno(r, "Failed to create root cgroup hierarchy: %m");
 
                 /* 5. And pin it, so that it cannot be unmounted */
                 safe_close(m->pin_cgroupfs_fd);
 
                 m->pin_cgroupfs_fd = open(path, O_RDONLY|O_CLOEXEC|O_DIRECTORY|O_NOCTTY|O_NONBLOCK);
-                if (m->pin_cgroupfs_fd < 0) {
-                        log_error("Failed to open pin file: %m");
-                        return -errno;
-                }
+                if (m->pin_cgroupfs_fd < 0)
+                        return log_error_errno(errno, "Failed to open pin file: %m");
 
-                /* 6.  Always enable hierarchial support if it exists... */
+                /* 6.  Always enable hierarchical support if it exists... */
                 cg_set_attribute("memory", "/", "memory.use_hierarchy", "1");
         }