X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fcore%2Fcgroup.c;h=1327486509a6eaaf54af54119087f077f8429f42;hp=4790a09ff24da9ecc2b9da8c09719fcd64500abc;hb=bdd13f6be4b588568683a1ab54f421fc6a636dbb;hpb=246aa6dd9dcea84bb945d16ec86e69f869dbb9b4 diff --git a/src/core/cgroup.c b/src/core/cgroup.c index 4790a09ff..132748650 100644 --- a/src/core/cgroup.c +++ b/src/core/cgroup.c @@ -3,7 +3,7 @@ /*** This file is part of systemd. - Copyright 2010 Lennart Poettering + Copyright 2013 Lennart Poettering systemd is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by @@ -19,569 +19,755 @@ along with systemd; If not, see . ***/ -#include -#include -#include -#include -#include -#include #include -#include "cgroup.h" -#include "cgroup-util.h" -#include "log.h" -#include "strv.h" #include "path-util.h" +#include "special.h" +#include "cgroup-util.h" +#include "cgroup.h" -int cgroup_bonding_realize(CGroupBonding *b) { - int r; +void cgroup_context_init(CGroupContext *c) { + assert(c); - assert(b); - assert(b->path); - assert(b->controller); + /* Initialize everything to the kernel defaults, assuming the + * structure is preinitialized to 0 */ - r = cg_create(b->controller, b->path); - if (r < 0) { - log_warning("Failed to create cgroup %s:%s: %s", b->controller, b->path, strerror(-r)); - return r; - } + c->cpu_shares = 1024; + c->memory_limit = (uint64_t) -1; + c->blockio_weight = 1000; +} - b->realized = true; +void cgroup_context_free_device_allow(CGroupContext *c, CGroupDeviceAllow *a) { + assert(c); + assert(a); - return 0; + LIST_REMOVE(device_allow, c->device_allow, a); + free(a->path); + free(a); } -int cgroup_bonding_realize_list(CGroupBonding *first) { - CGroupBonding *b; - int r; - - LIST_FOREACH(by_unit, b, first) - if ((r = cgroup_bonding_realize(b)) < 0 && b->essential) - return r; +void cgroup_context_free_blockio_device_weight(CGroupContext *c, CGroupBlockIODeviceWeight *w) { + assert(c); + assert(w); - return 0; + LIST_REMOVE(device_weights, c->blockio_device_weights, w); + free(w->path); + free(w); } -void cgroup_bonding_free(CGroupBonding *b, bool trim) { +void cgroup_context_free_blockio_device_bandwidth(CGroupContext *c, CGroupBlockIODeviceBandwidth *b) { + assert(c); assert(b); - if (b->unit) { - CGroupBonding *f; + LIST_REMOVE(device_bandwidths, c->blockio_device_bandwidths, b); + free(b->path); + free(b); +} - LIST_REMOVE(CGroupBonding, by_unit, b->unit->cgroup_bondings, b); +void cgroup_context_done(CGroupContext *c) { + assert(c); - if (streq(b->controller, SYSTEMD_CGROUP_CONTROLLER)) { - assert_se(f = hashmap_get(b->unit->manager->cgroup_bondings, b->path)); - LIST_REMOVE(CGroupBonding, by_path, f, b); + while (c->blockio_device_weights) + cgroup_context_free_blockio_device_weight(c, c->blockio_device_weights); - if (f) - hashmap_replace(b->unit->manager->cgroup_bondings, b->path, f); - else - hashmap_remove(b->unit->manager->cgroup_bondings, b->path); - } - } + while (c->blockio_device_bandwidths) + cgroup_context_free_blockio_device_bandwidth(c, c->blockio_device_bandwidths); - if (b->realized && b->ours && trim) - cg_trim(b->controller, b->path, false); + while (c->device_allow) + cgroup_context_free_device_allow(c, c->device_allow); +} - free(b->controller); - free(b->path); - free(b); +void cgroup_context_dump(CGroupContext *c, FILE* f, const char *prefix) { + CGroupBlockIODeviceBandwidth *b; + CGroupBlockIODeviceWeight *w; + CGroupDeviceAllow *a; + + assert(c); + assert(f); + + prefix = strempty(prefix); + + fprintf(f, + "%sCPUAccounting=%s\n" + "%sBlockIOAccounting=%s\n" + "%sMemoryAccounting=%s\n" + "%sCPUShares=%lu\n" + "%sBlockIOWeight=%lu\n" + "%sMemoryLimit=%" PRIu64 "\n" + "%sDevicePolicy=%s\n", + prefix, yes_no(c->cpu_accounting), + prefix, yes_no(c->blockio_accounting), + prefix, yes_no(c->memory_accounting), + prefix, c->cpu_shares, + prefix, c->blockio_weight, + prefix, c->memory_limit, + prefix, cgroup_device_policy_to_string(c->device_policy)); + + LIST_FOREACH(device_allow, a, c->device_allow) + fprintf(f, + "%sDeviceAllow=%s %s%s%s\n", + prefix, + a->path, + a->r ? "r" : "", a->w ? "w" : "", a->m ? "m" : ""); + + LIST_FOREACH(device_weights, w, c->blockio_device_weights) + fprintf(f, + "%sBlockIODeviceWeight=%s %lu", + prefix, + w->path, + w->weight); + + LIST_FOREACH(device_bandwidths, b, c->blockio_device_bandwidths) { + char buf[FORMAT_BYTES_MAX]; + + fprintf(f, + "%s%s=%s %s\n", + prefix, + b->read ? "BlockIOReadBandwidth" : "BlockIOWriteBandwidth", + b->path, + format_bytes(buf, sizeof(buf), b->bandwidth)); + } } -void cgroup_bonding_free_list(CGroupBonding *first, bool remove_or_trim) { - CGroupBonding *b, *n; +static int lookup_blkio_device(const char *p, dev_t *dev) { + struct stat st; + int r; - LIST_FOREACH_SAFE(by_unit, b, n, first) - cgroup_bonding_free(b, remove_or_trim); -} + assert(p); + assert(dev); -void cgroup_bonding_trim(CGroupBonding *b, bool delete_root) { - assert(b); + r = stat(p, &st); + if (r < 0) { + log_warning("Couldn't stat device %s: %m", p); + return -errno; + } - if (b->realized && b->ours) - cg_trim(b->controller, b->path, delete_root); -} + if (S_ISBLK(st.st_mode)) + *dev = st.st_rdev; + else if (major(st.st_dev) != 0) { + /* If this is not a device node then find the block + * device this file is stored on */ + *dev = st.st_dev; -void cgroup_bonding_trim_list(CGroupBonding *first, bool delete_root) { - CGroupBonding *b; + /* If this is a partition, try to get the originating + * block device */ + block_get_whole_disk(*dev, dev); + } else { + log_warning("%s is not a block device and file system block device cannot be determined or is not local.", p); + return -ENODEV; + } - LIST_FOREACH(by_unit, b, first) - cgroup_bonding_trim(b, delete_root); + return 0; } -int cgroup_bonding_install(CGroupBonding *b, pid_t pid, const char *cgroup_suffix) { - char *p = NULL; - const char *path; +static int whitelist_device(const char *path, const char *node, const char *acc) { + char buf[2+DECIMAL_STR_MAX(dev_t)*2+2+4]; + struct stat st; int r; - assert(b); - assert(pid >= 0); + assert(path); + assert(acc); - if (cgroup_suffix) { - p = strjoin(b->path, "/", cgroup_suffix, NULL); - if (!p) - return -ENOMEM; + if (stat(node, &st) < 0) { + log_warning("Couldn't stat device %s", node); + return -errno; + } - path = p; - } else - path = b->path; + if (!S_ISCHR(st.st_mode) && !S_ISBLK(st.st_mode)) { + log_warning("%s is not a device.", node); + return -ENODEV; + } - r = cg_create_and_attach(b->controller, path, pid); - free(p); + sprintf(buf, + "%c %u:%u %s", + S_ISCHR(st.st_mode) ? 'c' : 'b', + major(st.st_rdev), minor(st.st_rdev), + acc); + r = cg_set_attribute("devices", path, "devices.allow", buf); if (r < 0) - return r; + log_warning("Failed to set devices.allow on %s: %s", path, strerror(-r)); - b->realized = true; - return 0; + return r; } -int cgroup_bonding_install_list(CGroupBonding *first, pid_t pid, const char *cgroup_suffix) { - CGroupBonding *b; +static int whitelist_major(const char *path, const char *name, char type, const char *acc) { + _cleanup_fclose_ FILE *f = NULL; + char line[LINE_MAX]; + bool good = false; int r; - LIST_FOREACH(by_unit, b, first) { - r = cgroup_bonding_install(b, pid, cgroup_suffix); - if (r < 0 && b->essential) - return r; - } + assert(path); + assert(acc); + assert(type == 'b' || type == 'c'); - return 0; -} + f = fopen("/proc/devices", "re"); + if (!f) { + log_warning("Cannot open /proc/devices to resolve %s (%c): %m", name, type); + return -errno; + } -int cgroup_bonding_migrate(CGroupBonding *b, CGroupBonding *list) { - CGroupBonding *q; - int ret = 0; + FOREACH_LINE(line, f, goto fail) { + char buf[2+DECIMAL_STR_MAX(unsigned)+3+4], *p, *w; + unsigned maj; - LIST_FOREACH(by_unit, q, list) { - int r; + truncate_nl(line); - if (q == b) + if (type == 'c' && streq(line, "Character devices:")) { + good = true; continue; + } - if (!q->ours) + if (type == 'b' && streq(line, "Block devices:")) { + good = true; continue; + } - r = cg_migrate_recursive(q->controller, q->path, b->controller, b->path, true, false); - if (r < 0 && ret == 0) - ret = r; - } - - return ret; -} + if (isempty(line)) { + good = false; + continue; + } -int cgroup_bonding_migrate_to(CGroupBonding *b, const char *target, bool rem) { - assert(b); - assert(target); + if (!good) + continue; - return cg_migrate_recursive(b->controller, b->path, b->controller, target, true, rem); -} + p = strstrip(line); -int cgroup_bonding_set_group_access(CGroupBonding *b, mode_t mode, uid_t uid, gid_t gid) { - assert(b); + w = strpbrk(p, WHITESPACE); + if (!w) + continue; + *w = 0; - if (!b->realized) - return -EINVAL; + r = safe_atou(p, &maj); + if (r < 0) + continue; + if (maj <= 0) + continue; - return cg_set_group_access(b->controller, b->path, mode, uid, gid); -} + w++; + w += strspn(w, WHITESPACE); + if (!streq(w, name)) + continue; -int cgroup_bonding_set_group_access_list(CGroupBonding *first, mode_t mode, uid_t uid, gid_t gid) { - CGroupBonding *b; - int r; + sprintf(buf, + "%c %u:* %s", + type, + maj, + acc); - LIST_FOREACH(by_unit, b, first) { - r = cgroup_bonding_set_group_access(b, mode, uid, gid); + r = cg_set_attribute("devices", path, "devices.allow", buf); if (r < 0) - return r; + log_warning("Failed to set devices.allow on %s: %s", path, strerror(-r)); } return 0; + +fail: + log_warning("Failed to read /proc/devices: %m"); + return -errno; } -int cgroup_bonding_set_task_access(CGroupBonding *b, mode_t mode, uid_t uid, gid_t gid, int sticky) { - assert(b); +void cgroup_context_apply(CGroupContext *c, CGroupControllerMask mask, const char *path) { + bool is_root; + int r; - if (!b->realized) - return -EINVAL; + assert(c); + assert(path); - return cg_set_task_access(b->controller, b->path, mode, uid, gid, sticky); -} + if (mask == 0) + return; -int cgroup_bonding_set_task_access_list(CGroupBonding *first, mode_t mode, uid_t uid, gid_t gid, int sticky) { - CGroupBonding *b; - int r; + /* Some cgroup attributes are not support on the root cgroup, + * hence silently ignore */ + is_root = isempty(path) || path_equal(path, "/"); + + if ((mask & CGROUP_CPU) && !is_root) { + char buf[DECIMAL_STR_MAX(unsigned long) + 1]; - LIST_FOREACH(by_unit, b, first) { - r = cgroup_bonding_set_task_access(b, mode, uid, gid, sticky); + sprintf(buf, "%lu\n", c->cpu_shares); + r = cg_set_attribute("cpu", path, "cpu.shares", buf); if (r < 0) - return r; + log_warning("Failed to set cpu.shares on %s: %s", path, strerror(-r)); } - return 0; -} + if (mask & CGROUP_BLKIO) { + char buf[MAX3(DECIMAL_STR_MAX(unsigned long)+1, + DECIMAL_STR_MAX(dev_t)*2+2+DECIMAL_STR_MAX(unsigned long)*1, + DECIMAL_STR_MAX(dev_t)*2+2+DECIMAL_STR_MAX(uint64_t)+1)]; + CGroupBlockIODeviceWeight *w; + CGroupBlockIODeviceBandwidth *b; + + if (!is_root) { + sprintf(buf, "%lu\n", c->blockio_weight); + r = cg_set_attribute("blkio", path, "blkio.weight", buf); + if (r < 0) + log_warning("Failed to set blkio.weight on %s: %s", path, strerror(-r)); + + /* FIXME: no way to reset this list */ + LIST_FOREACH(device_weights, w, c->blockio_device_weights) { + dev_t dev; + + r = lookup_blkio_device(w->path, &dev); + if (r < 0) + continue; + + 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_error("Failed to set blkio.weight_device on %s: %s", path, strerror(-r)); + } + } -int cgroup_bonding_kill(CGroupBonding *b, int sig, bool sigcont, bool rem, Set *s, const char *cgroup_suffix) { - char *p = NULL; - const char *path; - int r; + /* FIXME: no way to reset this list */ + LIST_FOREACH(device_bandwidths, b, c->blockio_device_bandwidths) { + const char *a; + dev_t dev; - assert(b); - assert(sig >= 0); + r = lookup_blkio_device(b->path, &dev); + if (r < 0) + continue; - /* Don't kill cgroups that aren't ours */ - if (!b->ours) - return 0; + a = b->read ? "blkio.throttle.read_bps_device" : "blkio.throttle.write_bps_device"; - if (cgroup_suffix) { - p = strjoin(b->path, "/", cgroup_suffix, NULL); - if (!p) - return -ENOMEM; + sprintf(buf, "%u:%u %" PRIu64 "\n", major(dev), minor(dev), b->bandwidth); + r = cg_set_attribute("blkio", path, a, buf); + if (r < 0) + log_error("Failed to set %s on %s: %s", a, path, strerror(-r)); + } + } - path = p; - } else - path = b->path; + if (mask & CGROUP_MEMORY) { + if (c->memory_limit != (uint64_t) -1) { + char buf[DECIMAL_STR_MAX(uint64_t) + 1]; - r = cg_kill_recursive(b->controller, path, sig, sigcont, true, rem, s); - free(p); + sprintf(buf, "%" PRIu64 "\n", c->memory_limit); + r = cg_set_attribute("memory", path, "memory.limit_in_bytes", buf); + } else + r = cg_set_attribute("memory", path, "memory.limit_in_bytes", "-1"); - return r; -} + if (r < 0) + log_error("Failed to set memory.limit_in_bytes on %s: %s", path, strerror(-r)); + } -int cgroup_bonding_kill_list(CGroupBonding *first, int sig, bool sigcont, bool rem, Set *s, const char *cgroup_suffix) { - CGroupBonding *b; - Set *allocated_set = NULL; - int ret = -EAGAIN, r; + if ((mask & CGROUP_DEVICE) && !is_root) { + CGroupDeviceAllow *a; - if (!first) - return 0; + 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_warning("Failed to reset devices.list on %s: %s", path, strerror(-r)); - if (!s) - if (!(s = allocated_set = set_new(trivial_hash_func, trivial_compare_func))) - return -ENOMEM; + if (c->device_policy == CGROUP_CLOSED || + (c->device_policy == CGROUP_AUTO && c->device_allow)) { + static const char auto_devices[] = + "/dev/null\0" "rw\0" + "/dev/zero\0" "rw\0" + "/dev/full\0" "rw\0" + "/dev/random\0" "rw\0" + "/dev/urandom\0" "rw\0"; - LIST_FOREACH(by_unit, b, first) { - r = cgroup_bonding_kill(b, sig, sigcont, rem, s, cgroup_suffix); - if (r < 0) { - if (r == -EAGAIN || r == -ESRCH) - continue; + const char *x, *y; - ret = r; - goto finish; + NULSTR_FOREACH_PAIR(x, y, auto_devices) + whitelist_device(path, x, y); } - if (ret < 0 || r > 0) - ret = r; - } + LIST_FOREACH(device_allow, a, c->device_allow) { + char acc[4]; + unsigned k = 0; -finish: - if (allocated_set) - set_free(allocated_set); + if (a->r) + acc[k++] = 'r'; + if (a->w) + acc[k++] = 'w'; + if (a->m) + acc[k++] = 'm'; - return ret; + if (k == 0) + continue; + + acc[k++] = 0; + + if (startswith(a->path, "/dev/")) + whitelist_device(path, a->path, acc); + else if (startswith(a->path, "block-")) + whitelist_major(path, a->path + 6, 'b', acc); + else if (startswith(a->path, "char-")) + whitelist_major(path, a->path + 5, 'c', acc); + else + log_debug("Ignoring device %s while writing cgroup attribute.", a->path); + } + } } -/* Returns 1 if the group is empty, 0 if it is not, -EAGAIN if we - * cannot know */ -int cgroup_bonding_is_empty(CGroupBonding *b) { - int r; +CGroupControllerMask cgroup_context_get_mask(CGroupContext *c) { + CGroupControllerMask mask = 0; - assert(b); + /* Figure out which controllers we need */ - if ((r = cg_is_empty_recursive(b->controller, b->path, true)) < 0) - return r; + if (c->cpu_accounting || c->cpu_shares != 1024) + mask |= CGROUP_CPUACCT | CGROUP_CPU; - /* If it is empty it is empty */ - if (r > 0) - return 1; + if (c->blockio_accounting || + c->blockio_weight != 1000 || + c->blockio_device_weights || + c->blockio_device_bandwidths) + mask |= CGROUP_BLKIO; - /* It's not only us using this cgroup, so we just don't know */ - return b->ours ? 0 : -EAGAIN; -} + if (c->memory_accounting || + c->memory_limit != (uint64_t) -1) + mask |= CGROUP_MEMORY; -int cgroup_bonding_is_empty_list(CGroupBonding *first) { - CGroupBonding *b; + if (c->device_allow || c->device_policy != CGROUP_AUTO) + mask |= CGROUP_DEVICE; - LIST_FOREACH(by_unit, b, first) { - int r; + return mask; +} - if ((r = cgroup_bonding_is_empty(b)) < 0) { - /* If this returned -EAGAIN, then we don't know if the - * group is empty, so let's see if another group can - * tell us */ +CGroupControllerMask unit_get_cgroup_mask(Unit *u) { + CGroupContext *c; - if (r != -EAGAIN) - return r; - } else - return r; - } + c = unit_get_cgroup_context(u); + if (!c) + return 0; - return -EAGAIN; + return cgroup_context_get_mask(c); } -int manager_setup_cgroup(Manager *m) { - char *current = NULL, *path = NULL; - int r; - char suffix[32]; +CGroupControllerMask unit_get_members_mask(Unit *u) { + assert(u); - assert(m); + if (u->cgroup_members_mask_valid) + return u->cgroup_members_mask; - /* 0. Be nice to Ingo Molnar #628004 */ - if (path_is_mount_point("/sys/fs/cgroup/systemd", false) <= 0) { - log_warning("No control group support available, not creating root group."); - return 0; - } + u->cgroup_members_mask = 0; - /* 1. Determine hierarchy */ - r = cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, 0, ¤t); - if (r < 0) { - log_error("Cannot determine cgroup we are running in: %s", strerror(-r)); - goto finish; - } + if (u->type == UNIT_SLICE) { + Unit *member; + Iterator i; - if (m->running_as == SYSTEMD_SYSTEM) - strcpy(suffix, "/system"); - else { - snprintf(suffix, sizeof(suffix), "/systemd-%lu", (unsigned long) getpid()); - char_array_0(suffix); - } + SET_FOREACH(member, u->dependencies[UNIT_BEFORE], i) { - free(m->cgroup_hierarchy); - if (endswith(current, suffix)) { - /* We probably got reexecuted and can continue to use our root cgroup */ - m->cgroup_hierarchy = current; - current = NULL; + if (member == u) + continue; - } else { - /* We need a new root cgroup */ - m->cgroup_hierarchy = NULL; - if (asprintf(&m->cgroup_hierarchy, "%s%s", streq(current, "/") ? "" : current, suffix) < 0) { - r = log_oom(); - goto finish; + if (UNIT_DEREF(member->slice) != u) + continue; + + u->cgroup_members_mask |= + unit_get_cgroup_mask(member) | + unit_get_members_mask(member); } } - /* 2. Show data */ - r = cg_get_path(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_hierarchy, NULL, &path); - if (r < 0) { - log_error("Cannot find cgroup mount point: %s", strerror(-r)); - goto finish; - } + u->cgroup_members_mask_valid = true; + return u->cgroup_members_mask; +} - log_debug("Using cgroup controller " SYSTEMD_CGROUP_CONTROLLER ". File system hierarchy is at %s.", path); +CGroupControllerMask unit_get_siblings_mask(Unit *u) { + CGroupControllerMask m; - /* 3. Install agent */ - 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)); - else if (r > 0) - log_debug("Installed release agent."); + assert(u); + + if (UNIT_ISSET(u->slice)) + m = unit_get_members_mask(UNIT_DEREF(u->slice)); else - log_debug("Release agent already installed."); + m = unit_get_cgroup_mask(u) | unit_get_members_mask(u); - /* 4. Realize the group */ - r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_hierarchy, 0); - if (r < 0) { - log_error("Failed to create root cgroup hierarchy: %s", strerror(-r)); - goto finish; - } + /* Sibling propagation is only relevant for weight-based + * controllers, so let's mask out everything else */ + return m & (CGROUP_CPU|CGROUP_BLKIO|CGROUP_CPUACCT); +} - /* 5. And pin it, so that it cannot be unmounted */ - if (m->pin_cgroupfs_fd >= 0) - close_nointr_nofail(m->pin_cgroupfs_fd); +CGroupControllerMask unit_get_target_mask(Unit *u) { + CGroupControllerMask mask; - m->pin_cgroupfs_fd = open(path, O_RDONLY|O_CLOEXEC|O_DIRECTORY|O_NOCTTY|O_NONBLOCK); - if (r < 0) { - log_error("Failed to open pin file: %m"); - r = -errno; - goto finish; - } + mask = unit_get_cgroup_mask(u) | unit_get_members_mask(u) | unit_get_siblings_mask(u); + mask &= u->manager->cgroup_supported; - log_debug("Created root group."); + return mask; +} - cg_shorten_controllers(m->default_controllers); +/* Recurse from a unit up through its containing slices, propagating + * mask bits upward. A unit is also member of itself. */ +void unit_update_cgroup_members_masks(Unit *u) { + CGroupControllerMask m; + bool more; -finish: - free(current); - free(path); + assert(u); - return r; -} + /* Calculate subtree mask */ + m = unit_get_cgroup_mask(u) | unit_get_members_mask(u); -void manager_shutdown_cgroup(Manager *m, bool delete) { - assert(m); + /* See if anything changed from the previous invocation. If + * not, we're done. */ + if (u->cgroup_subtree_mask_valid && m == u->cgroup_subtree_mask) + return; - if (delete && m->cgroup_hierarchy) - cg_delete(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_hierarchy); + more = + u->cgroup_subtree_mask_valid && + ((m & ~u->cgroup_subtree_mask) != 0) && + ((~m & u->cgroup_subtree_mask) == 0); - if (m->pin_cgroupfs_fd >= 0) { - close_nointr_nofail(m->pin_cgroupfs_fd); - m->pin_cgroupfs_fd = -1; - } + u->cgroup_subtree_mask = m; + u->cgroup_subtree_mask_valid = true; - free(m->cgroup_hierarchy); - m->cgroup_hierarchy = NULL; -} + if (UNIT_ISSET(u->slice)) { + Unit *s = UNIT_DEREF(u->slice); -int cgroup_bonding_get(Manager *m, const char *cgroup, CGroupBonding **bonding) { - CGroupBonding *b; - char *p; + if (more) + /* There's more set now than before. We + * propagate the new mask to the parent's mask + * (not caring if it actually was valid or + * not). */ - assert(m); - assert(cgroup); - assert(bonding); + s->cgroup_members_mask |= m; - b = hashmap_get(m->cgroup_bondings, cgroup); - if (b) { - *bonding = b; - return 1; - } + else + /* There's less set now than before (or we + * don't know), we need to recalculate + * everything, so let's invalidate the + * parent's members mask */ - p = strdup(cgroup); - if (!p) - return -ENOMEM; + s->cgroup_members_mask_valid = false; - for (;;) { - char *e; + /* And now make sure that this change also hits our + * grandparents */ + unit_update_cgroup_members_masks(s); + } +} - e = strrchr(p, '/'); - if (!e || e == p) { - free(p); - *bonding = NULL; - return 0; - } +static const char *migrate_callback(CGroupControllerMask mask, void *userdata) { + Unit *u = userdata; - *e = 0; + assert(mask != 0); + assert(u); - b = hashmap_get(m->cgroup_bondings, p); - if (b) { - free(p); - *bonding = b; - return 1; - } + while (u) { + if (u->cgroup_path && + u->cgroup_realized && + (u->cgroup_realized_mask & mask) == mask) + return u->cgroup_path; + + u = UNIT_DEREF(u->slice); } + + return NULL; } -int cgroup_notify_empty(Manager *m, const char *group) { - CGroupBonding *l, *b; +static int unit_create_cgroups(Unit *u, CGroupControllerMask mask) { + _cleanup_free_ char *path = NULL; int r; - assert(m); - assert(group); + assert(u); + + path = unit_default_cgroup_path(u); + if (!path) + return log_oom(); - r = cgroup_bonding_get(m, group, &l); - if (r <= 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; + } - LIST_FOREACH(by_path, b, l) { - int t; + /* 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 (!b->unit) - continue; + /* Keep track that this is now realized */ + u->cgroup_realized = true; + u->cgroup_realized_mask = mask; - t = cgroup_bonding_is_empty_list(b); - if (t < 0) { + /* Then, possibly move things over */ + r = cg_migrate_everywhere(u->manager->cgroup_supported, u->cgroup_path, u->cgroup_path, migrate_callback, u); + if (r < 0) + log_warning("Failed to migrate cgroup from to %s: %s", u->cgroup_path, strerror(-r)); - /* If we don't know, we don't know */ - if (t != -EAGAIN) - log_warning("Failed to check whether cgroup is empty: %s", strerror(errno)); + return 0; +} - continue; - } +static bool unit_has_mask_realized(Unit *u, CGroupControllerMask mask) { + assert(u); + + return u->cgroup_realized && u->cgroup_realized_mask == mask; +} - if (t > 0) { - /* If it is empty, let's delete it */ - cgroup_bonding_trim_list(b->unit->cgroup_bondings, true); +/* Check if necessary controllers and attributes for a unit are in place. + * + * If so, do nothing. + * If not, create paths, move processes over, and set attributes. + * + * Returns 0 on success and < 0 on failure. */ +static int unit_realize_cgroup_now(Unit *u) { + CGroupControllerMask mask; + int r; - if (UNIT_VTABLE(b->unit)->cgroup_notify_empty) - UNIT_VTABLE(b->unit)->cgroup_notify_empty(b->unit); - } + assert(u); + + if (u->in_cgroup_queue) { + LIST_REMOVE(cgroup_queue, u->manager->cgroup_queue, u); + u->in_cgroup_queue = false; + } + + mask = unit_get_target_mask(u); + + if (unit_has_mask_realized(u, mask)) + return 0; + + /* First, realize parents */ + if (UNIT_ISSET(u->slice)) { + r = unit_realize_cgroup_now(UNIT_DEREF(u->slice)); + if (r < 0) + return r; } + /* And then do the real work */ + r = unit_create_cgroups(u, mask); + if (r < 0) + return r; + + /* Finally, apply the necessary attributes. */ + cgroup_context_apply(unit_get_cgroup_context(u), mask, u->cgroup_path); + return 0; } -Unit* cgroup_unit_by_pid(Manager *m, pid_t pid) { - CGroupBonding *l, *b; - char *group = NULL; +static void unit_add_to_cgroup_queue(Unit *u) { - assert(m); + if (u->in_cgroup_queue) + return; - if (pid <= 1) - return NULL; + LIST_PREPEND(cgroup_queue, u->manager->cgroup_queue, u); + u->in_cgroup_queue = true; +} - if (cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, pid, &group) < 0) - return NULL; +unsigned manager_dispatch_cgroup_queue(Manager *m) { + Unit *i; + unsigned n = 0; + int r; - l = hashmap_get(m->cgroup_bondings, group); + while ((i = m->cgroup_queue)) { + assert(i->in_cgroup_queue); - if (!l) { - char *slash; + r = unit_realize_cgroup_now(i); + if (r < 0) + log_warning("Failed to realize cgroups for queued unit %s: %s", i->id, strerror(-r)); - while ((slash = strrchr(group, '/'))) { - if (slash == group) - break; + n++; + } - *slash = 0; + return n; +} - if ((l = hashmap_get(m->cgroup_bondings, group))) - break; - } - } +static void unit_queue_siblings(Unit *u) { + Unit *slice; - free(group); + /* This adds the siblings of the specified unit and the + * siblings of all parent units to the cgroup queue. (But + * neither the specified unit itself nor the parents.) */ - LIST_FOREACH(by_path, b, l) { + while ((slice = UNIT_DEREF(u->slice))) { + Iterator i; + Unit *m; - if (!b->unit) - continue; + SET_FOREACH(m, slice->dependencies[UNIT_BEFORE], i) { + if (m == u) + continue; - if (b->ours) - return b->unit; - } + /* Skip units that have a dependency on the slice + * but aren't actually in it. */ + if (UNIT_DEREF(m->slice) != slice) + continue; - return NULL; + /* No point in doing cgroup application for units + * without active processes. */ + if (UNIT_IS_INACTIVE_OR_FAILED(unit_active_state(m))) + continue; + + /* If the unit doesn't need any new controllers + * and has current ones realized, it doesn't need + * any changes. */ + if (unit_has_mask_realized(m, unit_get_target_mask(m))) + continue; + + unit_add_to_cgroup_queue(m); + } + + u = slice; + } } -CGroupBonding *cgroup_bonding_find_list(CGroupBonding *first, const char *controller) { - CGroupBonding *b; +int unit_realize_cgroup(Unit *u) { + CGroupContext *c; - if (!controller) - controller = SYSTEMD_CGROUP_CONTROLLER; + assert(u); - LIST_FOREACH(by_unit, b, first) - if (streq(b->controller, controller)) - return b; + c = unit_get_cgroup_context(u); + if (!c) + return 0; - return NULL; + /* So, here's the deal: when realizing the cgroups for this + * unit, we need to first create all parents, but there's more + * actually: for the weight-based controllers we also need to + * make sure that all our siblings (i.e. units that are in the + * same slice as we are) have cgroups, too. Otherwise, things + * would become very uneven as each of their processes would + * get as much resources as all our group together. This call + * will synchronously create the parent cgroups, but will + * defer work on the siblings to the next event loop + * iteration. */ + + /* Add all sibling slices to the cgroup queue. */ + unit_queue_siblings(u); + + /* And realize this one now (and apply the values) */ + return unit_realize_cgroup_now(u); } -char *cgroup_bonding_to_string(CGroupBonding *b) { - char *r; +void unit_destroy_cgroup(Unit *u) { + int r; - assert(b); + assert(u); - if (asprintf(&r, "%s:%s", b->controller, b->path) < 0) - return NULL; + if (!u->cgroup_path) + 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)); + + hashmap_remove(u->manager->cgroup_unit, u->cgroup_path); + + free(u->cgroup_path); + u->cgroup_path = NULL; + u->cgroup_realized = false; + u->cgroup_realized_mask = 0; - return r; } -pid_t cgroup_bonding_search_main_pid(CGroupBonding *b) { - FILE *f; +pid_t unit_search_main_pid(Unit *u) { + _cleanup_fclose_ FILE *f = NULL; pid_t pid = 0, npid, mypid; - assert(b); + assert(u); - if (!b->ours) + if (!u->cgroup_path) return 0; - if (cg_enumerate_processes(b->controller, b->path, &f) < 0) + if (cg_enumerate_processes(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, &f) < 0) return 0; mypid = getpid(); - while (cg_read_pid(f, &npid) > 0) { pid_t ppid; @@ -603,24 +789,180 @@ pid_t cgroup_bonding_search_main_pid(CGroupBonding *b) { pid = npid; } - fclose(f); - return pid; } -pid_t cgroup_bonding_search_main_pid_list(CGroupBonding *first) { - CGroupBonding *b; - pid_t pid; +int manager_setup_cgroup(Manager *m) { + _cleanup_free_ char *path = NULL; + char *e; + int r; + + assert(m); + + /* 0. Be nice to Ingo Molnar #628004 */ + if (path_is_mount_point("/sys/fs/cgroup/systemd", false) <= 0) { + log_warning("No control group support available, not creating root group."); + return 0; + } - /* Try to find a main pid from this cgroup, but checking if - * there's only one PID in the cgroup and returning it. Later - * on we might want to add additional, smarter heuristics - * here. */ + /* 1. Determine hierarchy */ + free(m->cgroup_root); + m->cgroup_root = NULL; - LIST_FOREACH(by_unit, b, first) - if ((pid = cgroup_bonding_search_main_pid(b)) != 0) - return pid; + 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; + } + + /* LEGACY: Already in /system.slice? If so, let's cut this + * off. This is to support live upgrades from older systemd + * versions where PID 1 was moved there. */ + if (m->running_as == SYSTEMD_SYSTEM) { + e = endswith(m->cgroup_root, "/" SPECIAL_SYSTEM_SLICE); + if (!e) + e = endswith(m->cgroup_root, "/system"); + if (e) + *e = 0; + } + + /* And make sure to store away the root value without trailing + * slash, even for the root dir, so that we can easily prepend + * it everywhere. */ + if (streq(m->cgroup_root, "/")) + m->cgroup_root[0] = 0; + + /* 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; + } + + log_debug("Using cgroup controller " SYSTEMD_CGROUP_CONTROLLER ". File system hierarchy is at %s.", path); + + /* 3. Install agent */ + 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)); + else if (r > 0) + log_debug("Installed release agent."); + else + log_debug("Release agent already installed."); + } + + /* 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; + } + + /* 5. And pin it, so that it cannot be unmounted */ + if (m->pin_cgroupfs_fd >= 0) + close_nointr_nofail(m->pin_cgroupfs_fd); + + m->pin_cgroupfs_fd = open(path, O_RDONLY|O_CLOEXEC|O_DIRECTORY|O_NOCTTY|O_NONBLOCK); + if (r < 0) { + log_error("Failed to open pin file: %m"); + return -errno; + } + + /* 6. Figure out which controllers are supported */ + m->cgroup_supported = cg_mask_supported(); + + /* 7. Always enable hierarchial support if it exists... */ + cg_set_attribute("memory", "/", "memory.use_hierarchy", "1"); return 0; +} + +void manager_shutdown_cgroup(Manager *m, bool delete) { + assert(m); + + /* We can't really delete the group, since we are in it. But + * let's trim it. */ + if (delete && m->cgroup_root) + cg_trim(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_root, false); + + if (m->pin_cgroupfs_fd >= 0) { + close_nointr_nofail(m->pin_cgroupfs_fd); + m->pin_cgroupfs_fd = -1; + } + + free(m->cgroup_root); + m->cgroup_root = NULL; +} + +Unit* manager_get_unit_by_cgroup(Manager *m, const char *cgroup) { + char *p; + Unit *u; + + assert(m); + assert(cgroup); + u = hashmap_get(m->cgroup_unit, cgroup); + if (u) + return u; + + p = strdupa(cgroup); + for (;;) { + char *e; + + e = strrchr(p, '/'); + if (e == p || !e) + return NULL; + + *e = 0; + + u = hashmap_get(m->cgroup_unit, p); + if (u) + return u; + } } + +Unit *manager_get_unit_by_pid(Manager *m, pid_t pid) { + _cleanup_free_ char *cgroup = NULL; + int r; + + assert(m); + + if (pid <= 1) + return NULL; + + r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, pid, &cgroup); + if (r < 0) + return NULL; + + return manager_get_unit_by_cgroup(m, cgroup); +} + +int manager_notify_cgroup_empty(Manager *m, const char *cgroup) { + Unit *u; + int r; + + assert(m); + assert(cgroup); + + u = manager_get_unit_by_cgroup(m, cgroup); + if (u) { + r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, true); + if (r > 0) { + if (UNIT_VTABLE(u)->notify_cgroup_empty) + UNIT_VTABLE(u)->notify_cgroup_empty(u); + + unit_add_to_gc_queue(u); + } + } + + return 0; +} + +static const char* const cgroup_device_policy_table[_CGROUP_DEVICE_POLICY_MAX] = { + [CGROUP_AUTO] = "auto", + [CGROUP_CLOSED] = "closed", + [CGROUP_STRICT] = "strict", +}; + +DEFINE_STRING_TABLE_LOOKUP(cgroup_device_policy, CGroupDevicePolicy);