diff options
| -rw-r--r-- | Documentation/admin-guide/cgroup-v2.rst | 79 | ||||
| -rw-r--r-- | block/blk-cgroup.c | 10 | ||||
| -rw-r--r-- | include/linux/bpf-cgroup.h | 9 | ||||
| -rw-r--r-- | include/linux/cgroup-defs.h | 100 | ||||
| -rw-r--r-- | include/linux/cgroup.h | 24 | ||||
| -rw-r--r-- | include/trace/events/cgroup.h | 12 | ||||
| -rw-r--r-- | kernel/bpf/cgroup.c | 38 | ||||
| -rw-r--r-- | kernel/cgroup/cgroup-internal.h | 6 | ||||
| -rw-r--r-- | kernel/cgroup/cgroup.c | 148 | ||||
| -rw-r--r-- | kernel/cgroup/cpuset.c | 90 | ||||
| -rw-r--r-- | kernel/cgroup/rstat.c | 460 | ||||
| -rw-r--r-- | mm/memcontrol.c | 4 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/progs/btf_type_tag_percpu.c | 18 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/progs/cgroup_hierarchical_stats.c | 9 |
14 files changed, 665 insertions, 342 deletions
diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst index 9e7de8e70048..1edc26622594 100644 --- a/Documentation/admin-guide/cgroup-v2.rst +++ b/Documentation/admin-guide/cgroup-v2.rst @@ -1076,7 +1076,7 @@ cpufreq governor about the minimum desired frequency which should always be provided by a CPU, as well as the maximum desired frequency, which should not be exceeded by a CPU. -WARNING: cgroup2 cpu controller doesn't yet fully support the control of +WARNING: cgroup2 cpu controller doesn't yet support the (bandwidth) control of realtime processes. For a kernel built with the CONFIG_RT_GROUP_SCHED option enabled for group scheduling of realtime processes, the cpu controller can only be enabled when all RT processes are in the root cgroup. Be aware that system @@ -1095,19 +1095,34 @@ realtime processes irrespective of CONFIG_RT_GROUP_SCHED. CPU Interface Files ~~~~~~~~~~~~~~~~~~~ -All time durations are in microseconds. +The interaction of a process with the cpu controller depends on its scheduling +policy and the underlying scheduler. From the point of view of the cpu controller, +processes can be categorized as follows: + +* Processes under the fair-class scheduler +* Processes under a BPF scheduler with the ``cgroup_set_weight`` callback +* Everything else: ``SCHED_{FIFO,RR,DEADLINE}`` and processes under a BPF scheduler + without the ``cgroup_set_weight`` callback + +For details on when a process is under the fair-class scheduler or a BPF scheduler, +check out :ref:`Documentation/scheduler/sched-ext.rst <sched-ext>`. + +For each of the following interface files, the above categories +will be referred to. All time durations are in microseconds. cpu.stat A read-only flat-keyed file. This file exists whether the controller is enabled or not. - It always reports the following three stats: + It always reports the following three stats, which account for all the + processes in the cgroup: - usage_usec - user_usec - system_usec - and the following five when the controller is enabled: + and the following five when the controller is enabled, which account for + only the processes under the fair-class scheduler: - nr_periods - nr_throttled @@ -1125,6 +1140,10 @@ All time durations are in microseconds. If the cgroup has been configured to be SCHED_IDLE (cpu.idle = 1), then the weight will show as a 0. + This file affects only processes under the fair-class scheduler and a BPF + scheduler with the ``cgroup_set_weight`` callback depending on what the + callback actually does. + cpu.weight.nice A read-write single value file which exists on non-root cgroups. The default is "0". @@ -1137,6 +1156,10 @@ All time durations are in microseconds. granularity is coarser for the nice values, the read value is the closest approximation of the current weight. + This file affects only processes under the fair-class scheduler and a BPF + scheduler with the ``cgroup_set_weight`` callback depending on what the + callback actually does. + cpu.max A read-write two value file which exists on non-root cgroups. The default is "max 100000". @@ -1149,43 +1172,55 @@ All time durations are in microseconds. $PERIOD duration. "max" for $MAX indicates no limit. If only one number is written, $MAX is updated. + This file affects only processes under the fair-class scheduler. + cpu.max.burst A read-write single value file which exists on non-root cgroups. The default is "0". The burst in the range [0, $MAX]. + This file affects only processes under the fair-class scheduler. + cpu.pressure A read-write nested-keyed file. Shows pressure stall information for CPU. See :ref:`Documentation/accounting/psi.rst <psi>` for details. + This file accounts for all the processes in the cgroup. + cpu.uclamp.min - A read-write single value file which exists on non-root cgroups. - The default is "0", i.e. no utilization boosting. + A read-write single value file which exists on non-root cgroups. + The default is "0", i.e. no utilization boosting. + + The requested minimum utilization (protection) as a percentage + rational number, e.g. 12.34 for 12.34%. - The requested minimum utilization (protection) as a percentage - rational number, e.g. 12.34 for 12.34%. + This interface allows reading and setting minimum utilization clamp + values similar to the sched_setattr(2). This minimum utilization + value is used to clamp the task specific minimum utilization clamp, + including those of realtime processes. - This interface allows reading and setting minimum utilization clamp - values similar to the sched_setattr(2). This minimum utilization - value is used to clamp the task specific minimum utilization clamp. + The requested minimum utilization (protection) is always capped by + the current value for the maximum utilization (limit), i.e. + `cpu.uclamp.max`. - The requested minimum utilization (protection) is always capped by - the current value for the maximum utilization (limit), i.e. - `cpu.uclamp.max`. + This file affects all the processes in the cgroup. cpu.uclamp.max - A read-write single value file which exists on non-root cgroups. - The default is "max". i.e. no utilization capping + A read-write single value file which exists on non-root cgroups. + The default is "max". i.e. no utilization capping + + The requested maximum utilization (limit) as a percentage rational + number, e.g. 98.76 for 98.76%. - The requested maximum utilization (limit) as a percentage rational - number, e.g. 98.76 for 98.76%. + This interface allows reading and setting maximum utilization clamp + values similar to the sched_setattr(2). This maximum utilization + value is used to clamp the task specific maximum utilization clamp, + including those of realtime processes. - This interface allows reading and setting maximum utilization clamp - values similar to the sched_setattr(2). This maximum utilization - value is used to clamp the task specific maximum utilization clamp. + This file affects all the processes in the cgroup. cpu.idle A read-write single value file which exists on non-root cgroups. @@ -1197,7 +1232,7 @@ All time durations are in microseconds. own relative priorities, but the cgroup itself will be treated as very low priority relative to its peers. - + This file affects only processes under the fair-class scheduler. Memory ------ diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index ce93706555c5..5936db7f8475 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -1074,8 +1074,8 @@ static void __blkcg_rstat_flush(struct blkcg *blkcg, int cpu) /* * For covering concurrent parent blkg update from blkg_release(). * - * When flushing from cgroup, cgroup_rstat_lock is always held, so - * this lock won't cause contention most of time. + * When flushing from cgroup, the subsystem rstat lock is always held, + * so this lock won't cause contention most of time. */ raw_spin_lock_irqsave(&blkg_stat_lock, flags); @@ -1144,7 +1144,7 @@ static void blkcg_rstat_flush(struct cgroup_subsys_state *css, int cpu) /* * We source root cgroup stats from the system-wide stats to avoid * tracking the same information twice and incurring overhead when no - * cgroups are defined. For that reason, cgroup_rstat_flush in + * cgroups are defined. For that reason, css_rstat_flush in * blkcg_print_stat does not actually fill out the iostat in the root * cgroup's blkcg_gq. * @@ -1253,7 +1253,7 @@ static int blkcg_print_stat(struct seq_file *sf, void *v) if (!seq_css(sf)->parent) blkcg_fill_root_iostats(); else - cgroup_rstat_flush(blkcg->css.cgroup); + css_rstat_flush(&blkcg->css); rcu_read_lock(); hlist_for_each_entry_rcu(blkg, &blkcg->blkg_list, blkcg_node) { @@ -2243,7 +2243,7 @@ void blk_cgroup_bio_start(struct bio *bio) } u64_stats_update_end_irqrestore(&bis->sync, flags); - cgroup_rstat_updated(blkcg->css.cgroup, cpu); + css_rstat_updated(&blkcg->css, cpu); put_cpu(); } diff --git a/include/linux/bpf-cgroup.h b/include/linux/bpf-cgroup.h index 9de7adb68294..60d1511b4f4d 100644 --- a/include/linux/bpf-cgroup.h +++ b/include/linux/bpf-cgroup.h @@ -114,8 +114,7 @@ struct bpf_prog_list { u32 flags; }; -int cgroup_bpf_inherit(struct cgroup *cgrp); -void cgroup_bpf_offline(struct cgroup *cgrp); +void __init cgroup_bpf_lifetime_notifier_init(void); int __cgroup_bpf_run_filter_skb(struct sock *sk, struct sk_buff *skb, @@ -431,8 +430,10 @@ const struct bpf_func_proto * cgroup_current_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog); #else -static inline int cgroup_bpf_inherit(struct cgroup *cgrp) { return 0; } -static inline void cgroup_bpf_offline(struct cgroup *cgrp) {} +static inline void cgroup_bpf_lifetime_notifier_init(void) +{ + return; +} static inline int cgroup_bpf_prog_attach(const union bpf_attr *attr, enum bpf_prog_type ptype, diff --git a/include/linux/cgroup-defs.h b/include/linux/cgroup-defs.h index 5bc8f55c8cca..e61687d5e496 100644 --- a/include/linux/cgroup-defs.h +++ b/include/linux/cgroup-defs.h @@ -170,6 +170,23 @@ struct cgroup_subsys_state { struct percpu_ref refcnt; /* + * Depending on the context, this field is initialized + * via css_rstat_init() at different places: + * + * when css is associated with cgroup::self + * when css->cgroup is the root cgroup + * performed in cgroup_init() + * when css->cgroup is not the root cgroup + * performed in cgroup_create() + * when css is associated with a subsystem + * when css->cgroup is the root cgroup + * performed in cgroup_init_subsys() in the non-early path + * when css->cgroup is not the root cgroup + * performed in css_create() + */ + struct css_rstat_cpu __percpu *rstat_cpu; + + /* * siblings list anchored at the parent's ->children * * linkage is protected by cgroup_mutex or RCU @@ -177,9 +194,6 @@ struct cgroup_subsys_state { struct list_head sibling; struct list_head children; - /* flush target list anchored at cgrp->rstat_css_list */ - struct list_head rstat_css_node; - /* * PI: Subsys-unique ID. 0 is unused and root is always 1. The * matching css can be looked up using css_from_id(). @@ -219,6 +233,16 @@ struct cgroup_subsys_state { * Protected by cgroup_mutex. */ int nr_descendants; + + /* + * A singly-linked list of css structures to be rstat flushed. + * This is a scratch field to be used exclusively by + * css_rstat_flush(). + * + * Protected by rstat_base_lock when css is cgroup::self. + * Protected by css->ss->rstat_ss_lock otherwise. + */ + struct cgroup_subsys_state *rstat_flush_next; }; /* @@ -329,10 +353,10 @@ struct cgroup_base_stat { /* * rstat - cgroup scalable recursive statistics. Accounting is done - * per-cpu in cgroup_rstat_cpu which is then lazily propagated up the + * per-cpu in css_rstat_cpu which is then lazily propagated up the * hierarchy on reads. * - * When a stat gets updated, the cgroup_rstat_cpu and its ancestors are + * When a stat gets updated, the css_rstat_cpu and its ancestors are * linked into the updated tree. On the following read, propagation only * considers and consumes the updated tree. This makes reading O(the * number of descendants which have been active since last read) instead of @@ -344,10 +368,29 @@ struct cgroup_base_stat { * frequency decreases the cost of each read. * * This struct hosts both the fields which implement the above - - * updated_children and updated_next - and the fields which track basic - * resource statistics on top of it - bsync, bstat and last_bstat. + * updated_children and updated_next. */ -struct cgroup_rstat_cpu { +struct css_rstat_cpu { + /* + * Child cgroups with stat updates on this cpu since the last read + * are linked on the parent's ->updated_children through + * ->updated_next. updated_children is terminated by its container css. + * + * In addition to being more compact, singly-linked list pointing to + * the css makes it unnecessary for each per-cpu struct to point back + * to the associated css. + * + * Protected by per-cpu css->ss->rstat_ss_cpu_lock. + */ + struct cgroup_subsys_state *updated_children; + struct cgroup_subsys_state *updated_next; /* NULL if not on the list */ +}; + +/* + * This struct hosts the fields which track basic resource statistics on + * top of it - bsync, bstat and last_bstat. + */ +struct cgroup_rstat_base_cpu { /* * ->bsync protects ->bstat. These are the only fields which get * updated in the hot path. @@ -374,20 +417,6 @@ struct cgroup_rstat_cpu { * deltas to propagate to the per-cpu subtree_bstat. */ struct cgroup_base_stat last_subtree_bstat; - - /* - * Child cgroups with stat updates on this cpu since the last read - * are linked on the parent's ->updated_children through - * ->updated_next. - * - * In addition to being more compact, singly-linked list pointing - * to the cgroup makes it unnecessary for each per-cpu struct to - * point back to the associated cgroup. - * - * Protected by per-cpu cgroup_rstat_cpu_lock. - */ - struct cgroup *updated_children; /* terminated by self cgroup */ - struct cgroup *updated_next; /* NULL iff not on the list */ }; struct cgroup_freezer_state { @@ -516,23 +545,23 @@ struct cgroup { struct cgroup *dom_cgrp; struct cgroup *old_dom_cgrp; /* used while enabling threaded */ - /* per-cpu recursive resource statistics */ - struct cgroup_rstat_cpu __percpu *rstat_cpu; - struct list_head rstat_css_list; - /* - * Add padding to separate the read mostly rstat_cpu and - * rstat_css_list into a different cacheline from the following - * rstat_flush_next and *bstat fields which can have frequent updates. + * Depending on the context, this field is initialized via + * css_rstat_init() at different places: + * + * when cgroup is the root cgroup + * performed in cgroup_setup_root() + * otherwise + * performed in cgroup_create() */ - CACHELINE_PADDING(_pad_); + struct cgroup_rstat_base_cpu __percpu *rstat_base_cpu; /* - * A singly-linked list of cgroup structures to be rstat flushed. - * This is a scratch field to be used exclusively by - * cgroup_rstat_flush_locked() and protected by cgroup_rstat_lock. + * Add padding to keep the read mostly rstat per-cpu pointer on a + * different cacheline than the following *bstat fields which can have + * frequent updates. */ - struct cgroup *rstat_flush_next; + CACHELINE_PADDING(_pad_); /* cgroup basic resource statistics */ struct cgroup_base_stat last_bstat; @@ -790,6 +819,9 @@ struct cgroup_subsys { * specifies the mask of subsystems that this one depends on. */ unsigned int depends_on; + + spinlock_t rstat_ss_lock; + raw_spinlock_t __percpu *rstat_ss_cpu_lock; }; extern struct percpu_rw_semaphore cgroup_threadgroup_rwsem; diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 166d6de50dbf..b18fb5fcb38e 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -19,6 +19,7 @@ #include <linux/kernfs.h> #include <linux/jump_label.h> #include <linux/types.h> +#include <linux/notifier.h> #include <linux/ns_common.h> #include <linux/nsproxy.h> #include <linux/user_namespace.h> @@ -40,7 +41,7 @@ struct kernel_clone_args; #ifdef CONFIG_CGROUPS -enum { +enum css_task_iter_flags { CSS_TASK_ITER_PROCS = (1U << 0), /* walk only threadgroup leaders */ CSS_TASK_ITER_THREADED = (1U << 1), /* walk all threaded css_sets in the domain */ CSS_TASK_ITER_SKIPPED = (1U << 16), /* internal flags */ @@ -66,10 +67,16 @@ struct css_task_iter { struct list_head iters_node; /* css_set->task_iters */ }; +enum cgroup_lifetime_events { + CGROUP_LIFETIME_ONLINE, + CGROUP_LIFETIME_OFFLINE, +}; + extern struct file_system_type cgroup_fs_type; extern struct cgroup_root cgrp_dfl_root; extern struct css_set init_css_set; extern spinlock_t css_set_lock; +extern struct blocking_notifier_head cgroup_lifetime_notifier; #define SUBSYS(_x) extern struct cgroup_subsys _x ## _cgrp_subsys; #include <linux/cgroup_subsys.h> @@ -347,6 +354,17 @@ static inline bool css_is_dying(struct cgroup_subsys_state *css) return css->flags & CSS_DYING; } +static inline bool css_is_self(struct cgroup_subsys_state *css) +{ + if (css == &css->cgroup->self) { + /* cgroup::self should not have subsystem association */ + WARN_ON(css->ss != NULL); + return true; + } + + return false; +} + static inline void cgroup_get(struct cgroup *cgrp) { css_get(&cgrp->self); @@ -688,8 +706,8 @@ static inline void cgroup_path_from_kernfs_id(u64 id, char *buf, size_t buflen) /* * cgroup scalable recursive statistics. */ -void cgroup_rstat_updated(struct cgroup *cgrp, int cpu); -void cgroup_rstat_flush(struct cgroup *cgrp); +void css_rstat_updated(struct cgroup_subsys_state *css, int cpu); +void css_rstat_flush(struct cgroup_subsys_state *css); /* * Basic resource stats. diff --git a/include/trace/events/cgroup.h b/include/trace/events/cgroup.h index af2755bda6eb..7d332387be6c 100644 --- a/include/trace/events/cgroup.h +++ b/include/trace/events/cgroup.h @@ -231,7 +231,11 @@ DECLARE_EVENT_CLASS(cgroup_rstat, __entry->cpu, __entry->contended) ); -/* Related to global: cgroup_rstat_lock */ +/* + * Related to locks: + * global rstat_base_lock for base stats + * cgroup_subsys::rstat_ss_lock for subsystem stats + */ DEFINE_EVENT(cgroup_rstat, cgroup_rstat_lock_contended, TP_PROTO(struct cgroup *cgrp, int cpu, bool contended), @@ -253,7 +257,11 @@ DEFINE_EVENT(cgroup_rstat, cgroup_rstat_unlock, TP_ARGS(cgrp, cpu, contended) ); -/* Related to per CPU: cgroup_rstat_cpu_lock */ +/* + * Related to per CPU locks: + * global rstat_base_cpu_lock for base stats + * cgroup_subsys::rstat_ss_cpu_lock for subsystem stats + */ DEFINE_EVENT(cgroup_rstat, cgroup_rstat_cpu_lock_contended, TP_PROTO(struct cgroup *cgrp, int cpu, bool contended), diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c index 84f58f3d028a..cad0194552fb 100644 --- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -41,6 +41,19 @@ static int __init cgroup_bpf_wq_init(void) } core_initcall(cgroup_bpf_wq_init); +static int cgroup_bpf_lifetime_notify(struct notifier_block *nb, + unsigned long action, void *data); + +static struct notifier_block cgroup_bpf_lifetime_nb = { + .notifier_call = cgroup_bpf_lifetime_notify, +}; + +void __init cgroup_bpf_lifetime_notifier_init(void) +{ + BUG_ON(blocking_notifier_chain_register(&cgroup_lifetime_notifier, + &cgroup_bpf_lifetime_nb)); +} + /* __always_inline is necessary to prevent indirect call through run_prog * function pointer. */ @@ -206,7 +219,7 @@ bpf_cgroup_atype_find(enum bpf_attach_type attach_type, u32 attach_btf_id) } #endif /* CONFIG_BPF_LSM */ -void cgroup_bpf_offline(struct cgroup *cgrp) +static void cgroup_bpf_offline(struct cgroup *cgrp) { cgroup_get(cgrp); percpu_ref_kill(&cgrp->bpf.refcnt); @@ -491,7 +504,7 @@ static void activate_effective_progs(struct cgroup *cgrp, * cgroup_bpf_inherit() - inherit effective programs from parent * @cgrp: the cgroup to modify */ -int cgroup_bpf_inherit(struct cgroup *cgrp) +static int cgroup_bpf_inherit(struct cgroup *cgrp) { /* has to use marco instead of const int, since compiler thinks * that array below is variable length @@ -534,6 +547,27 @@ cleanup: return -ENOMEM; } +static int cgroup_bpf_lifetime_notify(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct cgroup *cgrp = data; + int ret = 0; + + if (cgrp->root != &cgrp_dfl_root) + return NOTIFY_OK; + + switch (action) { + case CGROUP_LIFETIME_ONLINE: + ret = cgroup_bpf_inherit(cgrp); + break; + case CGROUP_LIFETIME_OFFLINE: + cgroup_bpf_offline(cgrp); + break; + } + + return notifier_from_errno(ret); +} + static int update_effective_progs(struct cgroup *cgrp, enum cgroup_bpf_attach_type atype) { diff --git a/kernel/cgroup/cgroup-internal.h b/kernel/cgroup/cgroup-internal.h index 95ab39e1ec8f..b14e61c64a34 100644 --- a/kernel/cgroup/cgroup-internal.h +++ b/kernel/cgroup/cgroup-internal.h @@ -270,9 +270,9 @@ int cgroup_task_count(const struct cgroup *cgrp); /* * rstat.c */ -int cgroup_rstat_init(struct cgroup *cgrp); -void cgroup_rstat_exit(struct cgroup *cgrp); -void cgroup_rstat_boot(void); +int css_rstat_init(struct cgroup_subsys_state *css); +void css_rstat_exit(struct cgroup_subsys_state *css); +int ss_rstat_init(struct cgroup_subsys *ss); void cgroup_base_stat_cputime_show(struct seq_file *seq); /* diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index 63e5b90da1f3..a723b7dc6e4e 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -95,6 +95,9 @@ EXPORT_SYMBOL_GPL(cgroup_mutex); EXPORT_SYMBOL_GPL(css_set_lock); #endif +struct blocking_notifier_head cgroup_lifetime_notifier = + BLOCKING_NOTIFIER_INIT(cgroup_lifetime_notifier); + DEFINE_SPINLOCK(trace_cgroup_path_lock); char trace_cgroup_path[TRACE_CGROUP_PATH_LEN]; static bool cgroup_debug __read_mostly; @@ -161,10 +164,14 @@ static struct static_key_true *cgroup_subsys_on_dfl_key[] = { }; #undef SUBSYS -static DEFINE_PER_CPU(struct cgroup_rstat_cpu, cgrp_dfl_root_rstat_cpu); +static DEFINE_PER_CPU(struct css_rstat_cpu, root_rstat_cpu); +static DEFINE_PER_CPU(struct cgroup_rstat_base_cpu, root_rstat_base_cpu); /* the default hierarchy */ -struct cgroup_root cgrp_dfl_root = { .cgrp.rstat_cpu = &cgrp_dfl_root_rstat_cpu }; +struct cgroup_root cgrp_dfl_root = { + .cgrp.self.rstat_cpu = &root_rstat_cpu, + .cgrp.rstat_base_cpu = &root_rstat_base_cpu, +}; EXPORT_SYMBOL_GPL(cgrp_dfl_root); /* @@ -1335,6 +1342,7 @@ static void cgroup_destroy_root(struct cgroup_root *root) { struct cgroup *cgrp = &root->cgrp; struct cgrp_cset_link *link, *tmp_link; + int ret; trace_cgroup_destroy_root(root); @@ -1343,6 +1351,10 @@ static void cgroup_destroy_root(struct cgroup_root *root) BUG_ON(atomic_read(&root->nr_cgrps)); BUG_ON(!list_empty(&cgrp->self.children)); + ret = blocking_notifier_call_chain(&cgroup_lifetime_notifier, + CGROUP_LIFETIME_OFFLINE, cgrp); + WARN_ON_ONCE(notifier_to_errno(ret)); + /* Rebind all subsystems back to the default hierarchy */ WARN_ON(rebind_subsystems(&cgrp_dfl_root, root->subsys_mask)); @@ -1371,7 +1383,6 @@ static void cgroup_destroy_root(struct cgroup_root *root) cgroup_unlock(); - cgroup_rstat_exit(cgrp); kernfs_destroy_root(root->kf_root); cgroup_free_root(root); } @@ -1715,7 +1726,7 @@ static void css_clear_dir(struct cgroup_subsys_state *css) css->flags &= ~CSS_VISIBLE; - if (!css->ss) { + if (css_is_self(css)) { if (cgroup_on_dfl(cgrp)) { cgroup_addrm_files(css, cgrp, cgroup_base_files, false); @@ -1747,7 +1758,7 @@ static int css_populate_dir(struct cgroup_subsys_state *css) if (css->flags & CSS_VISIBLE) return 0; - if (!css->ss) { + if (css_is_self(css)) { if (cgroup_on_dfl(cgrp)) { ret = cgroup_addrm_files(css, cgrp, cgroup_base_files, true); @@ -1876,13 +1887,6 @@ int rebind_subsystems(struct cgroup_root *dst_root, u16 ss_mask) } spin_unlock_irq(&css_set_lock); - if (ss->css_rstat_flush) { - list_del_rcu(&css->rstat_css_node); - synchronize_rcu(); - list_add_rcu(&css->rstat_css_node, - &dcgrp->rstat_css_list); - } - /* default hierarchy doesn't enable controllers by default */ dst_root->subsys_mask |= 1 << ssid; if (dst_root == &cgrp_dfl_root) { @@ -2065,7 +2069,6 @@ static void init_cgroup_housekeeping(struct cgroup *cgrp) cgrp->dom_cgrp = cgrp; cgrp->max_descendants = INT_MAX; cgrp->max_depth = INT_MAX; - INIT_LIST_HEAD(&cgrp->rstat_css_list); prev_cputime_init(&cgrp->prev_cputime); for_each_subsys(ss, ssid) @@ -2146,7 +2149,7 @@ int cgroup_setup_root(struct cgroup_root *root, u16 ss_mask) if (ret) goto destroy_root; - ret = cgroup_rstat_init(root_cgrp); + ret = css_rstat_init(&root_cgrp->self); if (ret) goto destroy_root; @@ -2154,10 +2157,9 @@ int cgroup_setup_root(struct cgroup_root *root, u16 ss_mask) if (ret) goto exit_stats; - if (root == &cgrp_dfl_root) { - ret = cgroup_bpf_inherit(root_cgrp); - WARN_ON_ONCE(ret); - } + ret = blocking_notifier_call_chain(&cgroup_lifetime_notifier, + CGROUP_LIFETIME_ONLINE, root_cgrp); + WARN_ON_ONCE(notifier_to_errno(ret)); trace_cgroup_setup_root(root); @@ -2188,7 +2190,7 @@ int cgroup_setup_root(struct cgroup_root *root, u16 ss_mask) goto out; exit_stats: - cgroup_rstat_exit(root_cgrp); + css_rstat_exit(&root_cgrp->self); destroy_root: kernfs_destroy_root(root->kf_root); root->kf_root = NULL; @@ -5444,8 +5446,9 @@ static void css_free_rwork_fn(struct work_struct *work) struct cgroup *cgrp = css->cgroup; percpu_ref_exit(&css->refcnt); + css_rstat_exit(css); - if (ss) { + if (!css_is_self(css)) { /* css free path */ struct cgroup_subsys_state *parent = css->parent; int id = css->id; @@ -5474,7 +5477,6 @@ static void css_free_rwork_fn(struct work_struct *work) cgroup_put(cgroup_parent(cgrp)); kernfs_put(cgrp->kn); psi_cgroup_free(cgrp); - cgroup_rstat_exit(cgrp); kfree(cgrp); } else { /* @@ -5499,14 +5501,10 @@ static void css_release_work_fn(struct work_struct *work) css->flags |= CSS_RELEASED; list_del_rcu(&css->sibling); - if (ss) { + if (!css_is_self(css)) { struct cgroup *parent_cgrp; - /* css release path */ - if (!list_empty(&css->rstat_css_node)) { - cgroup_rstat_flush(cgrp); - list_del_rcu(&css->rstat_css_node); - } + css_rstat_flush(css); cgroup_idr_replace(&ss->css_idr, NULL, css->id); if (ss->css_released) @@ -5532,7 +5530,7 @@ static void css_release_work_fn(struct work_struct *work) /* cgroup release path */ TRACE_CGROUP_PATH(release, cgrp); - cgroup_rstat_flush(cgrp); + css_rstat_flush(&cgrp->self); spin_lock_irq(&css_set_lock); for (tcgrp = cgroup_parent(cgrp); tcgrp; @@ -5580,7 +5578,6 @@ static void init_and_link_css(struct cgroup_subsys_state *css, css->id = -1; INIT_LIST_HEAD(&css->sibling); INIT_LIST_HEAD(&css->children); - INIT_LIST_HEAD(&css->rstat_css_node); css->serial_nr = css_serial_nr_next++; atomic_set(&css->online_cnt, 0); @@ -5589,9 +5586,6 @@ static void init_and_link_css(struct cgroup_subsys_state *css, css_get(css->parent); } - if (ss->css_rstat_flush) - list_add_rcu(&css->rstat_css_node, &cgrp->rstat_css_list); - BUG_ON(cgroup_css(cgrp, ss)); } @@ -5684,6 +5678,10 @@ static struct cgroup_subsys_state *css_create(struct cgroup *cgrp, goto err_free_css; css->id = err; + err = css_rstat_init(css); + if (err) + goto err_free_css; + /* @css is ready to be brought online now, make it visible */ list_add_tail_rcu(&css->sibling, &parent_css->children); cgroup_idr_replace(&ss->css_idr, css, css->id); @@ -5697,7 +5695,6 @@ static struct cgroup_subsys_state *css_create(struct cgroup *cgrp, err_list_del: list_del_rcu(&css->sibling); err_free_css: - list_del_rcu(&css->rstat_css_node); INIT_RCU_WORK(&css->destroy_rwork, css_free_rwork_fn); queue_rcu_work(cgroup_destroy_wq, &css->destroy_rwork); return ERR_PTR(err); @@ -5713,7 +5710,7 @@ static struct cgroup *cgroup_create(struct cgroup *parent, const char *name, struct cgroup_root *root = parent->root; struct cgroup *cgrp, *tcgrp; struct kernfs_node *kn; - int level = parent->level + 1; + int i, level = parent->level + 1; int ret; /* allocate the cgroup and its ID, 0 is reserved for the root */ @@ -5725,17 +5722,13 @@ static struct cgroup *cgroup_create(struct cgroup *parent, const char *name, if (ret) goto out_free_cgrp; - ret = cgroup_rstat_init(cgrp); - if (ret) - goto out_cancel_ref; - /* create the directory */ kn = kernfs_create_dir_ns(parent->kn, name, mode, current_fsuid(), current_fsgid(), cgrp, NULL); if (IS_ERR(kn)) { ret = PTR_ERR(kn); - goto out_stat_exit; + goto out_cancel_ref; } cgrp->kn = kn; @@ -5745,15 +5738,20 @@ static struct cgroup *cgroup_create(struct cgroup *parent, const char *name, cgrp->root = root; cgrp->level = level; - ret = psi_cgroup_alloc(cgrp); + /* + * Now that init_cgroup_housekeeping() has been called and cgrp->self + * is setup, it is safe to perform rstat initialization on it. + */ + ret = css_rstat_init(&cgrp->self); if (ret) goto out_kernfs_remove; - if (cgrp->root == &cgrp_dfl_root) { - ret = cgroup_bpf_inherit(cgrp); - if (ret) - goto out_psi_free; - } + ret = psi_cgroup_alloc(cgrp); + if (ret) + goto out_stat_exit; + + for (tcgrp = cgrp; tcgrp; tcgrp = cgroup_parent(tcgrp)) + cgrp->ancestors[tcgrp->level] = tcgrp; /* * New cgroup inherits effective freeze counter, and @@ -5771,24 +5769,6 @@ static struct cgroup *cgroup_create(struct cgroup *parent, const char *name, set_bit(CGRP_FROZEN, &cgrp->flags); } - spin_lock_irq(&css_set_lock); - for (tcgrp = cgrp; tcgrp; tcgrp = cgroup_parent(tcgrp)) { - cgrp->ancestors[tcgrp->level] = tcgrp; - - if (tcgrp != cgrp) { - tcgrp->nr_descendants++; - - /* - * If the new cgroup is frozen, all ancestor cgroups - * get a new frozen descendant, but their state can't - * change because of this. - */ - if (cgrp->freezer.e_freeze) - tcgrp->freezer.nr_frozen_descendants++; - } - } - spin_unlock_irq(&css_set_lock); - if (notify_on_release(parent)) set_bit(CGRP_NOTIFY_ON_RELEASE, &cgrp->flags); @@ -5797,7 +5777,29 @@ static struct cgroup *cgroup_create(struct cgroup *parent, const char *name, cgrp->self.serial_nr = css_serial_nr_next++; + ret = blocking_notifier_call_chain_robust(&cgroup_lifetime_notifier, + CGROUP_LIFETIME_ONLINE, + CGROUP_LIFETIME_OFFLINE, cgrp); + ret = notifier_to_errno(ret); + if (ret) + goto out_psi_free; + /* allocation complete, commit to creation */ + spin_lock_irq(&css_set_lock); + for (i = 0; i < level; i++) { + tcgrp = cgrp->ancestors[i]; + tcgrp->nr_descendants++; + + /* + * If the new cgroup is frozen, all ancestor cgroups get a new + * frozen descendant, but their state can't change because of + * this. + */ + if (cgrp->freezer.e_freeze) + tcgrp->freezer.nr_frozen_descendants++; + } + spin_unlock_irq(&css_set_lock); + list_add_tail_rcu(&cgrp->self.sibling, &cgroup_parent(cgrp)->self.children); atomic_inc(&root->nr_cgrps); cgroup_get_live(parent); @@ -5815,10 +5817,10 @@ static struct cgroup *cgroup_create(struct cgroup *parent, const char *name, out_psi_free: psi_cgroup_free(cgrp); +out_stat_exit: + css_rstat_exit(&cgrp->self); out_kernfs_remove: kernfs_remove(cgrp->kn); -out_stat_exit: - cgroup_rstat_exit(cgrp); out_cancel_ref: percpu_ref_exit(&cgrp->self.refcnt); out_free_cgrp: @@ -6015,7 +6017,7 @@ static int cgroup_destroy_locked(struct cgroup *cgrp) struct cgroup *tcgrp, *parent = cgroup_parent(cgrp); struct cgroup_subsys_state *css; struct cgrp_cset_link *link; - int ssid; + int ssid, ret; lockdep_assert_held(&cgroup_mutex); @@ -6073,8 +6075,9 @@ static int cgroup_destroy_locked(struct cgroup *cgrp) cgroup1_check_for_release(parent); - if (cgrp->root == &cgrp_dfl_root) - cgroup_bpf_offline(cgrp); + ret = blocking_notifier_call_chain(&cgroup_lifetime_notifier, + CGROUP_LIFETIME_OFFLINE, cgrp); + WARN_ON_ONCE(notifier_to_errno(ret)); /* put the base reference */ percpu_ref_kill(&cgrp->self.refcnt); @@ -6136,6 +6139,9 @@ static void __init cgroup_init_subsys(struct cgroup_subsys *ss, bool early) } else { css->id = cgroup_idr_alloc(&ss->css_idr, css, 1, 2, GFP_KERNEL); BUG_ON(css->id < 0); + + BUG_ON(ss_rstat_init(ss)); + BUG_ON(css_rstat_init(css)); } /* Update the init_css_set to contain a subsys @@ -6184,6 +6190,8 @@ int __init cgroup_init_early(void) ss->id, ss->name); WARN(strlen(cgroup_subsys_name[i]) > MAX_CGROUP_TYPE_NAMELEN, "cgroup_subsys_name %s too long\n", cgroup_subsys_name[i]); + WARN(ss->early_init && ss->css_rstat_flush, + "cgroup rstat cannot be used with early init subsystem\n"); ss->id = i; ss->name = cgroup_subsys_name[i]; @@ -6212,7 +6220,7 @@ int __init cgroup_init(void) BUG_ON(cgroup_init_cftypes(NULL, cgroup_psi_files)); BUG_ON(cgroup_init_cftypes(NULL, cgroup1_base_files)); - cgroup_rstat_boot(); + BUG_ON(ss_rstat_init(NULL)); get_user_ns(init_cgroup_ns.user_ns); @@ -6225,6 +6233,8 @@ int __init cgroup_init(void) hash_add(css_set_table, &init_css_set.hlist, css_set_hash(init_css_set.subsys)); + cgroup_bpf_lifetime_notifier_init(); + BUG_ON(cgroup_setup_root(&cgrp_dfl_root, 0)); cgroup_unlock(); diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index 24b70ea3e6ce..6d3ac19cc2ac 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -192,6 +192,20 @@ static inline void notify_partition_change(struct cpuset *cs, int old_prs) WRITE_ONCE(cs->prs_err, PERR_NONE); } +/* + * The top_cpuset is always synchronized to cpu_active_mask and we should avoid + * using cpu_online_mask as much as possible. An active CPU is always an online + * CPU, but not vice versa. cpu_active_mask and cpu_online_mask can differ + * during hotplug operations. A CPU is marked active at the last stage of CPU + * bringup (CPUHP_AP_ACTIVE). It is also the stage where cpuset hotplug code + * will be called to update the sched domains so that the scheduler can move + * a normal task to a newly active CPU or remove tasks away from a newly + * inactivated CPU. The online bit is set much earlier in the CPU bringup + * process and cleared much later in CPU teardown. + * + * If cpu_online_mask is used while a hotunplug operation is happening in + * parallel, we may leave an offline CPU in cpu_allowed or some other masks. + */ static struct cpuset top_cpuset = { .flags = BIT(CS_ONLINE) | BIT(CS_CPU_EXCLUSIVE) | BIT(CS_MEM_EXCLUSIVE) | BIT(CS_SCHED_LOAD_BALANCE), @@ -355,18 +369,18 @@ static inline bool partition_is_populated(struct cpuset *cs, * appropriate cpus. * * One way or another, we guarantee to return some non-empty subset - * of cpu_online_mask. + * of cpu_active_mask. * * Call with callback_lock or cpuset_mutex held. */ -static void guarantee_online_cpus(struct task_struct *tsk, +static void guarantee_active_cpus(struct task_struct *tsk, struct cpumask *pmask) { const struct cpumask *possible_mask = task_cpu_possible_mask(tsk); struct cpuset *cs; - if (WARN_ON(!cpumask_and(pmask, possible_mask, cpu_online_mask))) - cpumask_copy(pmask, cpu_online_mask); + if (WARN_ON(!cpumask_and(pmask, possible_mask, cpu_active_mask))) + cpumask_copy(pmask, cpu_active_mask); rcu_read_lock(); cs = task_cs(tsk); @@ -1390,14 +1404,12 @@ static int compute_effective_exclusive_cpumask(struct cpuset *cs, if (sibling == cs) continue; - if (!cpumask_empty(sibling->exclusive_cpus) && - cpumask_intersects(xcpus, sibling->exclusive_cpus)) { + if (cpumask_intersects(xcpus, sibling->exclusive_cpus)) { cpumask_andnot(xcpus, xcpus, sibling->exclusive_cpus); retval++; continue; } - if (!cpumask_empty(sibling->effective_xcpus) && - cpumask_intersects(xcpus, sibling->effective_xcpus)) { + if (cpumask_intersects(xcpus, sibling->effective_xcpus)) { cpumask_andnot(xcpus, xcpus, sibling->effective_xcpus); retval++; } @@ -1441,13 +1453,15 @@ static int remote_partition_enable(struct cpuset *cs, int new_prs, * The requested exclusive_cpus must not be allocated to other * partitions and it can't use up all the root's effective_cpus. * - * Note that if there is any local partition root above it or - * remote partition root underneath it, its exclusive_cpus must - * have overlapped with subpartitions_cpus. + * The effective_xcpus mask can contain offline CPUs, but there must + * be at least one or more online CPUs present before it can be enabled. + * + * Note that creating a remote partition with any local partition root + * above it or remote partition root underneath it is not allowed. */ compute_effective_exclusive_cpumask(cs, tmp->new_cpus, NULL); - if (cpumask_empty(tmp->new_cpus) || - cpumask_intersects(tmp->new_cpus, subpartitions_cpus) || + WARN_ON_ONCE(cpumask_intersects(tmp->new_cpus, subpartitions_cpus)); + if (!cpumask_intersects(tmp->new_cpus, cpu_active_mask) || cpumask_subset(top_cpuset.effective_cpus, tmp->new_cpus)) return PERR_INVCPUS; @@ -1543,6 +1557,7 @@ static void remote_cpus_update(struct cpuset *cs, struct cpumask *xcpus, * left in the top cpuset. */ if (adding) { + WARN_ON_ONCE(cpumask_intersects(tmp->addmask, subpartitions_cpus)); if (!capable(CAP_SYS_ADMIN)) cs->prs_err = PERR_ACCESS; else if (cpumask_intersects(tmp->addmask, subpartitions_cpus) || @@ -1652,7 +1667,7 @@ static int update_parent_effective_cpumask(struct cpuset *cs, int cmd, bool nocpu; lockdep_assert_held(&cpuset_mutex); - WARN_ON_ONCE(is_remote_partition(cs)); + WARN_ON_ONCE(is_remote_partition(cs)); /* For local partition only */ /* * new_prs will only be changed for the partcmd_update and @@ -1698,7 +1713,7 @@ static int update_parent_effective_cpumask(struct cpuset *cs, int cmd, * exclusive_cpus not set. Sibling conflict should only happen * if exclusive_cpus isn't set. */ - xcpus = tmp->new_cpus; + xcpus = tmp->delmask; if (compute_effective_exclusive_cpumask(cs, xcpus, NULL)) WARN_ON_ONCE(!cpumask_empty(cs->exclusive_cpus)); @@ -1719,9 +1734,20 @@ static int update_parent_effective_cpumask(struct cpuset *cs, int cmd, if (nocpu) return PERR_NOCPUS; - deleting = cpumask_and(tmp->delmask, xcpus, parent->effective_xcpus); - if (deleting) - subparts_delta++; + /* + * This function will only be called when all the preliminary + * checks have passed. At this point, the following condition + * should hold. + * + * (cs->effective_xcpus & cpu_active_mask) ⊆ parent->effective_cpus + * + * Warn if it is not the case. + */ + cpumask_and(tmp->new_cpus, xcpus, cpu_active_mask); + WARN_ON_ONCE(!cpumask_subset(tmp->new_cpus, parent->effective_cpus)); + + deleting = true; + subparts_delta++; new_prs = (cmd == partcmd_enable) ? PRS_ROOT : PRS_ISOLATED; } else if (cmd == partcmd_disable) { /* @@ -1776,6 +1802,15 @@ static int update_parent_effective_cpumask(struct cpuset *cs, int cmd, parent->effective_xcpus); } /* + * The new CPUs to be removed from parent's effective CPUs + * must be present. + */ + if (deleting) { + cpumask_and(tmp->new_cpus, tmp->delmask, cpu_active_mask); + WARN_ON_ONCE(!cpumask_subset(tmp->new_cpus, parent->effective_cpus)); + } + + /* * Make partition invalid if parent's effective_cpus could * become empty and there are tasks in the parent. */ @@ -2265,7 +2300,7 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs, bool force = false; int old_prs = cs->partition_root_state; - /* top_cpuset.cpus_allowed tracks cpu_online_mask; it's read-only */ + /* top_cpuset.cpus_allowed tracks cpu_active_mask; it's read-only */ if (cs == &top_cpuset) return -EACCES; @@ -3084,7 +3119,7 @@ static void cpuset_attach_task(struct cpuset *cs, struct task_struct *task) lockdep_assert_held(&cpuset_mutex); if (cs != &top_cpuset) - guarantee_online_cpus(task, cpus_attach); + guarantee_active_cpus(task, cpus_attach); else cpumask_andnot(cpus_attach, task_cpu_possible_mask(task), subpartitions_cpus); @@ -3526,11 +3561,7 @@ out_unlock: * will call rebuild_sched_domains_locked(). That is not needed * in the default hierarchy where only changes in partition * will cause repartitioning. - * - * If the cpuset has the 'sched.partition' flag enabled, simulate - * turning 'sched.partition" off. */ - static void cpuset_css_offline(struct cgroup_subsys_state *css) { struct cpuset *cs = css_cs(css); @@ -3548,6 +3579,11 @@ static void cpuset_css_offline(struct cgroup_subsys_state *css) cpus_read_unlock(); } +/* + * If a dying cpuset has the 'cpus.partition' enabled, turn it off by + * changing it back to member to free its exclusive CPUs back to the pool to + * be used by other online cpusets. + */ static void cpuset_css_killed(struct cgroup_subsys_state *css) { struct cpuset *cs = css_cs(css); @@ -4028,7 +4064,7 @@ void __init cpuset_init_smp(void) * * Description: Returns the cpumask_var_t cpus_allowed of the cpuset * attached to the specified @tsk. Guaranteed to return some non-empty - * subset of cpu_online_mask, even if this means going outside the + * subset of cpu_active_mask, even if this means going outside the * tasks cpuset, except when the task is in the top cpuset. **/ @@ -4042,7 +4078,7 @@ void cpuset_cpus_allowed(struct task_struct *tsk, struct cpumask *pmask) cs = task_cs(tsk); if (cs != &top_cpuset) - guarantee_online_cpus(tsk, pmask); + guarantee_active_cpus(tsk, pmask); /* * Tasks in the top cpuset won't get update to their cpumasks * when a hotplug online/offline event happens. So we include all @@ -4056,7 +4092,7 @@ void cpuset_cpus_allowed(struct task_struct *tsk, struct cpumask *pmask) * allowable online cpu left, we fall back to all possible cpus. */ cpumask_andnot(pmask, possible_mask, subpartitions_cpus); - if (!cpumask_intersects(pmask, cpu_online_mask)) + if (!cpumask_intersects(pmask, cpu_active_mask)) cpumask_copy(pmask, possible_mask); } diff --git a/kernel/cgroup/rstat.c b/kernel/cgroup/rstat.c index b2239156b7de..ce4752ab9e09 100644 --- a/kernel/cgroup/rstat.c +++ b/kernel/cgroup/rstat.c @@ -9,18 +9,52 @@ #include <trace/events/cgroup.h> -static DEFINE_SPINLOCK(cgroup_rstat_lock); -static DEFINE_PER_CPU(raw_spinlock_t, cgroup_rstat_cpu_lock); +static DEFINE_SPINLOCK(rstat_base_lock); +static DEFINE_PER_CPU(raw_spinlock_t, rstat_base_cpu_lock); static void cgroup_base_stat_flush(struct cgroup *cgrp, int cpu); -static struct cgroup_rstat_cpu *cgroup_rstat_cpu(struct cgroup *cgrp, int cpu) +/* + * Determines whether a given css can participate in rstat. + * css's that are cgroup::self use rstat for base stats. + * Other css's associated with a subsystem use rstat only when + * they define the ss->css_rstat_flush callback. + */ +static inline bool css_uses_rstat(struct cgroup_subsys_state *css) +{ + return css_is_self(css) || css->ss->css_rstat_flush != NULL; +} + +static struct css_rstat_cpu *css_rstat_cpu( + struct cgroup_subsys_state *css, int cpu) +{ + return per_cpu_ptr(css->rstat_cpu, cpu); +} + +static struct cgroup_rstat_base_cpu *cgroup_rstat_base_cpu( + struct cgroup *cgrp, int cpu) { - return per_cpu_ptr(cgrp->rstat_cpu, cpu); + return per_cpu_ptr(cgrp->rstat_base_cpu, cpu); +} + +static spinlock_t *ss_rstat_lock(struct cgroup_subsys *ss) +{ + if (ss) + return &ss->rstat_ss_lock; + + return &rstat_base_lock; +} + +static raw_spinlock_t *ss_rstat_cpu_lock(struct cgroup_subsys *ss, int cpu) +{ + if (ss) + return per_cpu_ptr(ss->rstat_ss_cpu_lock, cpu); + + return per_cpu_ptr(&rstat_base_cpu_lock, cpu); } /* - * Helper functions for rstat per CPU lock (cgroup_rstat_cpu_lock). + * Helper functions for rstat per CPU locks. * * This makes it easier to diagnose locking issues and contention in * production environments. The parameter @fast_path determine the @@ -28,20 +62,23 @@ static struct cgroup_rstat_cpu *cgroup_rstat_cpu(struct cgroup *cgrp, int cpu) * operations without handling high-frequency fast-path "update" events. */ static __always_inline -unsigned long _cgroup_rstat_cpu_lock(raw_spinlock_t *cpu_lock, int cpu, - struct cgroup *cgrp, const bool fast_path) +unsigned long _css_rstat_cpu_lock(struct cgroup_subsys_state *css, int cpu, + const bool fast_path) { + struct cgroup *cgrp = css->cgroup; + raw_spinlock_t *cpu_lock; unsigned long flags; bool contended; /* - * The _irqsave() is needed because cgroup_rstat_lock is - * spinlock_t which is a sleeping lock on PREEMPT_RT. Acquiring - * this lock with the _irq() suffix only disables interrupts on - * a non-PREEMPT_RT kernel. The raw_spinlock_t below disables - * interrupts on both configurations. The _irqsave() ensures - * that interrupts are always disabled and later restored. + * The _irqsave() is needed because the locks used for flushing are + * spinlock_t which is a sleeping lock on PREEMPT_RT. Acquiring this lock + * with the _irq() suffix only disables interrupts on a non-PREEMPT_RT + * kernel. The raw_spinlock_t below disables interrupts on both + * configurations. The _irqsave() ensures that interrupts are always + * disabled and later restored. */ + cpu_lock = ss_rstat_cpu_lock(css->ss, cpu); contended = !raw_spin_trylock_irqsave(cpu_lock, flags); if (contended) { if (fast_path) @@ -61,50 +98,59 @@ unsigned long _cgroup_rstat_cpu_lock(raw_spinlock_t *cpu_lock, int cpu, } static __always_inline -void _cgroup_rstat_cpu_unlock(raw_spinlock_t *cpu_lock, int cpu, - struct cgroup *cgrp, unsigned long flags, - const bool fast_path) +void _css_rstat_cpu_unlock(struct cgroup_subsys_state *css, int cpu, + unsigned long flags, const bool fast_path) { + struct cgroup *cgrp = css->cgroup; + raw_spinlock_t *cpu_lock; + if (fast_path) trace_cgroup_rstat_cpu_unlock_fastpath(cgrp, cpu, false); else trace_cgroup_rstat_cpu_unlock(cgrp, cpu, false); + cpu_lock = ss_rstat_cpu_lock(css->ss, cpu); raw_spin_unlock_irqrestore(cpu_lock, flags); } /** - * cgroup_rstat_updated - keep track of updated rstat_cpu - * @cgrp: target cgroup + * css_rstat_updated - keep track of updated rstat_cpu + * @css: target cgroup subsystem state * @cpu: cpu on which rstat_cpu was updated * - * @cgrp's rstat_cpu on @cpu was updated. Put it on the parent's matching - * rstat_cpu->updated_children list. See the comment on top of - * cgroup_rstat_cpu definition for details. + * @css's rstat_cpu on @cpu was updated. Put it on the parent's matching + * rstat_cpu->updated_children list. See the comment on top of + * css_rstat_cpu definition for details. */ -__bpf_kfunc void cgroup_rstat_updated(struct cgroup *cgrp, int cpu) +__bpf_kfunc void css_rstat_updated(struct cgroup_subsys_state *css, int cpu) { - raw_spinlock_t *cpu_lock = per_cpu_ptr(&cgroup_rstat_cpu_lock, cpu); unsigned long flags; /* + * Since bpf programs can call this function, prevent access to + * uninitialized rstat pointers. + */ + if (!css_uses_rstat(css)) + return; + + /* * Speculative already-on-list test. This may race leading to * temporary inaccuracies, which is fine. * * Because @parent's updated_children is terminated with @parent - * instead of NULL, we can tell whether @cgrp is on the list by + * instead of NULL, we can tell whether @css is on the list by * testing the next pointer for NULL. */ - if (data_race(cgroup_rstat_cpu(cgrp, cpu)->updated_next)) + if (data_race(css_rstat_cpu(css, cpu)->updated_next)) return; - flags = _cgroup_rstat_cpu_lock(cpu_lock, cpu, cgrp, true); + flags = _css_rstat_cpu_lock(css, cpu, true); - /* put @cgrp and all ancestors on the corresponding updated lists */ + /* put @css and all ancestors on the corresponding updated lists */ while (true) { - struct cgroup_rstat_cpu *rstatc = cgroup_rstat_cpu(cgrp, cpu); - struct cgroup *parent = cgroup_parent(cgrp); - struct cgroup_rstat_cpu *prstatc; + struct css_rstat_cpu *rstatc = css_rstat_cpu(css, cpu); + struct cgroup_subsys_state *parent = css->parent; + struct css_rstat_cpu *prstatc; /* * Both additions and removals are bottom-up. If a cgroup @@ -115,53 +161,78 @@ __bpf_kfunc void cgroup_rstat_updated(struct cgroup *cgrp, int cpu) /* Root has no parent to link it to, but mark it busy */ if (!parent) { - rstatc->updated_next = cgrp; + rstatc->updated_next = css; break; } - prstatc = cgroup_rstat_cpu(parent, cpu); + prstatc = css_rstat_cpu(parent, cpu); rstatc->updated_next = prstatc->updated_children; - prstatc->updated_children = cgrp; + prstatc->updated_children = css; - cgrp = parent; + css = parent; } - _cgroup_rstat_cpu_unlock(cpu_lock, cpu, cgrp, flags, true); + _css_rstat_cpu_unlock(css, cpu, flags, true); } /** - * cgroup_rstat_push_children - push children cgroups into the given list + * css_rstat_push_children - push children css's into the given list * @head: current head of the list (= subtree root) * @child: first child of the root * @cpu: target cpu - * Return: A new singly linked list of cgroups to be flush + * Return: A new singly linked list of css's to be flushed * - * Iteratively traverse down the cgroup_rstat_cpu updated tree level by + * Iteratively traverse down the css_rstat_cpu updated tree level by * level and push all the parents first before their next level children - * into a singly linked list built from the tail backward like "pushing" - * cgroups into a stack. The root is pushed by the caller. + * into a singly linked list via the rstat_flush_next pointer built from the + * tail backward like "pushing" css's into a stack. The root is pushed by + * the caller. */ -static struct cgroup *cgroup_rstat_push_children(struct cgroup *head, - struct cgroup *child, int cpu) +static struct cgroup_subsys_state *css_rstat_push_children( + struct cgroup_subsys_state *head, + struct cgroup_subsys_state *child, int cpu) { - struct cgroup *chead = child; /* Head of child cgroup level */ - struct cgroup *ghead = NULL; /* Head of grandchild cgroup level */ - struct cgroup *parent, *grandchild; - struct cgroup_rstat_cpu *crstatc; + struct cgroup_subsys_state *cnext = child; /* Next head of child css level */ + struct cgroup_subsys_state *ghead = NULL; /* Head of grandchild css level */ + struct cgroup_subsys_state *parent, *grandchild; + struct css_rstat_cpu *crstatc; child->rstat_flush_next = NULL; + /* + * The subsystem rstat lock must be held for the whole duration from + * here as the rstat_flush_next list is being constructed to when + * it is consumed later in css_rstat_flush(). + */ + lockdep_assert_held(ss_rstat_lock(head->ss)); + + /* + * Notation: -> updated_next pointer + * => rstat_flush_next pointer + * + * Assuming the following sample updated_children lists: + * P: C1 -> C2 -> P + * C1: G11 -> G12 -> C1 + * C2: G21 -> G22 -> C2 + * + * After 1st iteration: + * head => C2 => C1 => NULL + * ghead => G21 => G11 => NULL + * + * After 2nd iteration: + * head => G12 => G11 => G22 => G21 => C2 => C1 => NULL + */ next_level: - while (chead) { - child = chead; - chead = child->rstat_flush_next; - parent = cgroup_parent(child); + while (cnext) { + child = cnext; + cnext = child->rstat_flush_next; + parent = child->parent; - /* updated_next is parent cgroup terminated */ + /* updated_next is parent cgroup terminated if !NULL */ while (child != parent) { child->rstat_flush_next = head; head = child; - crstatc = cgroup_rstat_cpu(child, cpu); + crstatc = css_rstat_cpu(child, cpu); grandchild = crstatc->updated_children; if (grandchild != child) { /* Push the grand child to the next level */ @@ -175,7 +246,7 @@ next_level: } if (ghead) { - chead = ghead; + cnext = ghead; ghead = NULL; goto next_level; } @@ -183,31 +254,31 @@ next_level: } /** - * cgroup_rstat_updated_list - return a list of updated cgroups to be flushed - * @root: root of the cgroup subtree to traverse + * css_rstat_updated_list - build a list of updated css's to be flushed + * @root: root of the css subtree to traverse * @cpu: target cpu - * Return: A singly linked list of cgroups to be flushed + * Return: A singly linked list of css's to be flushed * * Walks the updated rstat_cpu tree on @cpu from @root. During traversal, - * each returned cgroup is unlinked from the updated tree. + * each returned css is unlinked from the updated tree. * * The only ordering guarantee is that, for a parent and a child pair * covered by a given traversal, the child is before its parent in * the list. * * Note that updated_children is self terminated and points to a list of - * child cgroups if not empty. Whereas updated_next is like a sibling link - * within the children list and terminated by the parent cgroup. An exception - * here is the cgroup root whose updated_next can be self terminated. + * child css's if not empty. Whereas updated_next is like a sibling link + * within the children list and terminated by the parent css. An exception + * here is the css root whose updated_next can be self terminated. */ -static struct cgroup *cgroup_rstat_updated_list(struct cgroup *root, int cpu) +static struct cgroup_subsys_state *css_rstat_updated_list( + struct cgroup_subsys_state *root, int cpu) { - raw_spinlock_t *cpu_lock = per_cpu_ptr(&cgroup_rstat_cpu_lock, cpu); - struct cgroup_rstat_cpu *rstatc = cgroup_rstat_cpu(root, cpu); - struct cgroup *head = NULL, *parent, *child; + struct css_rstat_cpu *rstatc = css_rstat_cpu(root, cpu); + struct cgroup_subsys_state *head = NULL, *parent, *child; unsigned long flags; - flags = _cgroup_rstat_cpu_lock(cpu_lock, cpu, root, false); + flags = _css_rstat_cpu_lock(root, cpu, false); /* Return NULL if this subtree is not on-list */ if (!rstatc->updated_next) @@ -217,17 +288,17 @@ static struct cgroup *cgroup_rstat_updated_list(struct cgroup *root, int cpu) * Unlink @root from its parent. As the updated_children list is * singly linked, we have to walk it to find the removal point. */ - parent = cgroup_parent(root); + parent = root->parent; if (parent) { - struct cgroup_rstat_cpu *prstatc; - struct cgroup **nextp; + struct css_rstat_cpu *prstatc; + struct cgroup_subsys_state **nextp; - prstatc = cgroup_rstat_cpu(parent, cpu); + prstatc = css_rstat_cpu(parent, cpu); nextp = &prstatc->updated_children; while (*nextp != root) { - struct cgroup_rstat_cpu *nrstatc; + struct css_rstat_cpu *nrstatc; - nrstatc = cgroup_rstat_cpu(*nextp, cpu); + nrstatc = css_rstat_cpu(*nextp, cpu); WARN_ON_ONCE(*nextp == parent); nextp = &nrstatc->updated_next; } @@ -242,16 +313,16 @@ static struct cgroup *cgroup_rstat_updated_list(struct cgroup *root, int cpu) child = rstatc->updated_children; rstatc->updated_children = root; if (child != root) - head = cgroup_rstat_push_children(head, child, cpu); + head = css_rstat_push_children(head, child, cpu); unlock_ret: - _cgroup_rstat_cpu_unlock(cpu_lock, cpu, root, flags, false); + _css_rstat_cpu_unlock(root, cpu, flags, false); return head; } /* * A hook for bpf stat collectors to attach to and flush their stats. - * Together with providing bpf kfuncs for cgroup_rstat_updated() and - * cgroup_rstat_flush(), this enables a complete workflow where bpf progs that + * Together with providing bpf kfuncs for css_rstat_updated() and + * css_rstat_flush(), this enables a complete workflow where bpf progs that * collect cgroup stats can integrate with rstat for efficient flushing. * * A static noinline declaration here could cause the compiler to optimize away @@ -271,7 +342,7 @@ __weak noinline void bpf_rstat_flush(struct cgroup *cgrp, __bpf_hook_end(); /* - * Helper functions for locking cgroup_rstat_lock. + * Helper functions for locking. * * This makes it easier to diagnose locking issues and contention in * production environments. The parameter @cpu_in_loop indicate lock @@ -279,115 +350,186 @@ __bpf_hook_end(); * value -1 is used when obtaining the main lock else this is the CPU * number processed last. */ -static inline void __cgroup_rstat_lock(struct cgroup *cgrp, int cpu_in_loop) - __acquires(&cgroup_rstat_lock) +static inline void __css_rstat_lock(struct cgroup_subsys_state *css, + int cpu_in_loop) + __acquires(ss_rstat_lock(css->ss)) { + struct cgroup *cgrp = css->cgroup; + spinlock_t *lock; bool contended; - contended = !spin_trylock_irq(&cgroup_rstat_lock); + lock = ss_rstat_lock(css->ss); + contended = !spin_trylock_irq(lock); if (contended) { trace_cgroup_rstat_lock_contended(cgrp, cpu_in_loop, contended); - spin_lock_irq(&cgroup_rstat_lock); + spin_lock_irq(lock); } trace_cgroup_rstat_locked(cgrp, cpu_in_loop, contended); } -static inline void __cgroup_rstat_unlock(struct cgroup *cgrp, int cpu_in_loop) - __releases(&cgroup_rstat_lock) +static inline void __css_rstat_unlock(struct cgroup_subsys_state *css, + int cpu_in_loop) + __releases(ss_rstat_lock(css->ss)) { + struct cgroup *cgrp = css->cgroup; + spinlock_t *lock; + + lock = ss_rstat_lock(css->ss); trace_cgroup_rstat_unlock(cgrp, cpu_in_loop, false); - spin_unlock_irq(&cgroup_rstat_lock); + spin_unlock_irq(lock); } /** - * cgroup_rstat_flush - flush stats in @cgrp's subtree - * @cgrp: target cgroup + * css_rstat_flush - flush stats in @css's rstat subtree + * @css: target cgroup subsystem state * - * Collect all per-cpu stats in @cgrp's subtree into the global counters - * and propagate them upwards. After this function returns, all cgroups in - * the subtree have up-to-date ->stat. + * Collect all per-cpu stats in @css's subtree into the global counters + * and propagate them upwards. After this function returns, all rstat + * nodes in the subtree have up-to-date ->stat. * - * This also gets all cgroups in the subtree including @cgrp off the + * This also gets all rstat nodes in the subtree including @css off the * ->updated_children lists. * * This function may block. */ -__bpf_kfunc void cgroup_rstat_flush(struct cgroup *cgrp) +__bpf_kfunc void css_rstat_flush(struct cgroup_subsys_state *css) { int cpu; + bool is_self = css_is_self(css); + + /* + * Since bpf programs can call this function, prevent access to + * uninitialized rstat pointers. + */ + if (!css_uses_rstat(css)) + return; might_sleep(); for_each_possible_cpu(cpu) { - struct cgroup *pos; + struct cgroup_subsys_state *pos; /* Reacquire for each CPU to avoid disabling IRQs too long */ - __cgroup_rstat_lock(cgrp, cpu); - pos = cgroup_rstat_updated_list(cgrp, cpu); + __css_rstat_lock(css, cpu); + pos = css_rstat_updated_list(css, cpu); for (; pos; pos = pos->rstat_flush_next) { - struct cgroup_subsys_state *css; - - cgroup_base_stat_flush(pos, cpu); - bpf_rstat_flush(pos, cgroup_parent(pos), cpu); - - rcu_read_lock(); - list_for_each_entry_rcu(css, &pos->rstat_css_list, - rstat_css_node) - css->ss->css_rstat_flush(css, cpu); - rcu_read_unlock(); + if (is_self) { + cgroup_base_stat_flush(pos->cgroup, cpu); + bpf_rstat_flush(pos->cgroup, + cgroup_parent(pos->cgroup), cpu); + } else + pos->ss->css_rstat_flush(pos, cpu); } - __cgroup_rstat_unlock(cgrp, cpu); + __css_rstat_unlock(css, cpu); if (!cond_resched()) cpu_relax(); } } -int cgroup_rstat_init(struct cgroup *cgrp) +int css_rstat_init(struct cgroup_subsys_state *css) { + struct cgroup *cgrp = css->cgroup; int cpu; + bool is_self = css_is_self(css); + + if (is_self) { + /* the root cgrp has rstat_base_cpu preallocated */ + if (!cgrp->rstat_base_cpu) { + cgrp->rstat_base_cpu = alloc_percpu(struct cgroup_rstat_base_cpu); + if (!cgrp->rstat_base_cpu) + return -ENOMEM; + } + } else if (css->ss->css_rstat_flush == NULL) + return 0; + + /* the root cgrp's self css has rstat_cpu preallocated */ + if (!css->rstat_cpu) { + css->rstat_cpu = alloc_percpu(struct css_rstat_cpu); + if (!css->rstat_cpu) { + if (is_self) + free_percpu(cgrp->rstat_base_cpu); - /* the root cgrp has rstat_cpu preallocated */ - if (!cgrp->rstat_cpu) { - cgrp->rstat_cpu = alloc_percpu(struct cgroup_rstat_cpu); - if (!cgrp->rstat_cpu) return -ENOMEM; + } } /* ->updated_children list is self terminated */ for_each_possible_cpu(cpu) { - struct cgroup_rstat_cpu *rstatc = cgroup_rstat_cpu(cgrp, cpu); + struct css_rstat_cpu *rstatc = css_rstat_cpu(css, cpu); + + rstatc->updated_children = css; + + if (is_self) { + struct cgroup_rstat_base_cpu *rstatbc; - rstatc->updated_children = cgrp; - u64_stats_init(&rstatc->bsync); + rstatbc = cgroup_rstat_base_cpu(cgrp, cpu); + u64_stats_init(&rstatbc->bsync); + } } return 0; } -void cgroup_rstat_exit(struct cgroup *cgrp) +void css_rstat_exit(struct cgroup_subsys_state *css) { int cpu; - cgroup_rstat_flush(cgrp); + if (!css_uses_rstat(css)) + return; + + css_rstat_flush(css); /* sanity check */ for_each_possible_cpu(cpu) { - struct cgroup_rstat_cpu *rstatc = cgroup_rstat_cpu(cgrp, cpu); + struct css_rstat_cpu *rstatc = css_rstat_cpu(css, cpu); - if (WARN_ON_ONCE(rstatc->updated_children != cgrp) || + if (WARN_ON_ONCE(rstatc->updated_children != css) || WARN_ON_ONCE(rstatc->updated_next)) return; } - free_percpu(cgrp->rstat_cpu); - cgrp->rstat_cpu = NULL; + if (css_is_self(css)) { + struct cgroup *cgrp = css->cgroup; + + free_percpu(cgrp->rstat_base_cpu); + cgrp->rstat_base_cpu = NULL; + } + + free_percpu(css->rstat_cpu); + css->rstat_cpu = NULL; } -void __init cgroup_rstat_boot(void) +/** + * ss_rstat_init - subsystem-specific rstat initialization + * @ss: target subsystem + * + * If @ss is NULL, the static locks associated with the base stats + * are initialized. If @ss is non-NULL, the subsystem-specific locks + * are initialized. + */ +int __init ss_rstat_init(struct cgroup_subsys *ss) { int cpu; +#ifdef CONFIG_SMP + /* + * On uniprocessor machines, arch_spinlock_t is defined as an empty + * struct. Avoid allocating a size of zero by having this block + * excluded in this case. It's acceptable to leave the subsystem locks + * unitialized since the associated lock functions are no-ops in the + * non-smp case. + */ + if (ss) { + ss->rstat_ss_cpu_lock = alloc_percpu(raw_spinlock_t); + if (!ss->rstat_ss_cpu_lock) + return -ENOMEM; + } +#endif + + spin_lock_init(ss_rstat_lock(ss)); for_each_possible_cpu(cpu) - raw_spin_lock_init(per_cpu_ptr(&cgroup_rstat_cpu_lock, cpu)); + raw_spin_lock_init(ss_rstat_cpu_lock(ss, cpu)); + + return 0; } /* @@ -420,9 +562,9 @@ static void cgroup_base_stat_sub(struct cgroup_base_stat *dst_bstat, static void cgroup_base_stat_flush(struct cgroup *cgrp, int cpu) { - struct cgroup_rstat_cpu *rstatc = cgroup_rstat_cpu(cgrp, cpu); + struct cgroup_rstat_base_cpu *rstatbc = cgroup_rstat_base_cpu(cgrp, cpu); struct cgroup *parent = cgroup_parent(cgrp); - struct cgroup_rstat_cpu *prstatc; + struct cgroup_rstat_base_cpu *prstatbc; struct cgroup_base_stat delta; unsigned seq; @@ -432,15 +574,15 @@ static void cgroup_base_stat_flush(struct cgroup *cgrp, int cpu) /* fetch the current per-cpu values */ do { - seq = __u64_stats_fetch_begin(&rstatc->bsync); - delta = rstatc->bstat; - } while (__u64_stats_fetch_retry(&rstatc->bsync, seq)); + seq = __u64_stats_fetch_begin(&rstatbc->bsync); + delta = rstatbc->bstat; + } while (__u64_stats_fetch_retry(&rstatbc->bsync, seq)); /* propagate per-cpu delta to cgroup and per-cpu global statistics */ - cgroup_base_stat_sub(&delta, &rstatc->last_bstat); + cgroup_base_stat_sub(&delta, &rstatbc->last_bstat); cgroup_base_stat_add(&cgrp->bstat, &delta); - cgroup_base_stat_add(&rstatc->last_bstat, &delta); - cgroup_base_stat_add(&rstatc->subtree_bstat, &delta); + cgroup_base_stat_add(&rstatbc->last_bstat, &delta); + cgroup_base_stat_add(&rstatbc->subtree_bstat, &delta); /* propagate cgroup and per-cpu global delta to parent (unless that's root) */ if (cgroup_parent(parent)) { @@ -449,73 +591,73 @@ static void cgroup_base_stat_flush(struct cgroup *cgrp, int cpu) cgroup_base_stat_add(&parent->bstat, &delta); cgroup_base_stat_add(&cgrp->last_bstat, &delta); - delta = rstatc->subtree_bstat; - prstatc = cgroup_rstat_cpu(parent, cpu); - cgroup_base_stat_sub(&delta, &rstatc->last_subtree_bstat); - cgroup_base_stat_add(&prstatc->subtree_bstat, &delta); - cgroup_base_stat_add(&rstatc->last_subtree_bstat, &delta); + delta = rstatbc->subtree_bstat; + prstatbc = cgroup_rstat_base_cpu(parent, cpu); + cgroup_base_stat_sub(&delta, &rstatbc->last_subtree_bstat); + cgroup_base_stat_add(&prstatbc->subtree_bstat, &delta); + cgroup_base_stat_add(&rstatbc->last_subtree_bstat, &delta); } } -static struct cgroup_rstat_cpu * +static struct cgroup_rstat_base_cpu * cgroup_base_stat_cputime_account_begin(struct cgroup *cgrp, unsigned long *flags) { - struct cgroup_rstat_cpu *rstatc; + struct cgroup_rstat_base_cpu *rstatbc; - rstatc = get_cpu_ptr(cgrp->rstat_cpu); - *flags = u64_stats_update_begin_irqsave(&rstatc->bsync); - return rstatc; + rstatbc = get_cpu_ptr(cgrp->rstat_base_cpu); + *flags = u64_stats_update_begin_irqsave(&rstatbc->bsync); + return rstatbc; } static void cgroup_base_stat_cputime_account_end(struct cgroup *cgrp, - struct cgroup_rstat_cpu *rstatc, + struct cgroup_rstat_base_cpu *rstatbc, unsigned long flags) { - u64_stats_update_end_irqrestore(&rstatc->bsync, flags); - cgroup_rstat_updated(cgrp, smp_processor_id()); - put_cpu_ptr(rstatc); + u64_stats_update_end_irqrestore(&rstatbc->bsync, flags); + css_rstat_updated(&cgrp->self, smp_processor_id()); + put_cpu_ptr(rstatbc); } void __cgroup_account_cputime(struct cgroup *cgrp, u64 delta_exec) { - struct cgroup_rstat_cpu *rstatc; + struct cgroup_rstat_base_cpu *rstatbc; unsigned long flags; - rstatc = cgroup_base_stat_cputime_account_begin(cgrp, &flags); - rstatc->bstat.cputime.sum_exec_runtime += delta_exec; - cgroup_base_stat_cputime_account_end(cgrp, rstatc, flags); + rstatbc = cgroup_base_stat_cputime_account_begin(cgrp, &flags); + rstatbc->bstat.cputime.sum_exec_runtime += delta_exec; + cgroup_base_stat_cputime_account_end(cgrp, rstatbc, flags); } void __cgroup_account_cputime_field(struct cgroup *cgrp, enum cpu_usage_stat index, u64 delta_exec) { - struct cgroup_rstat_cpu *rstatc; + struct cgroup_rstat_base_cpu *rstatbc; unsigned long flags; - rstatc = cgroup_base_stat_cputime_account_begin(cgrp, &flags); + rstatbc = cgroup_base_stat_cputime_account_begin(cgrp, &flags); switch (index) { case CPUTIME_NICE: - rstatc->bstat.ntime += delta_exec; + rstatbc->bstat.ntime += delta_exec; fallthrough; case CPUTIME_USER: - rstatc->bstat.cputime.utime += delta_exec; + rstatbc->bstat.cputime.utime += delta_exec; break; case CPUTIME_SYSTEM: case CPUTIME_IRQ: case CPUTIME_SOFTIRQ: - rstatc->bstat.cputime.stime += delta_exec; + rstatbc->bstat.cputime.stime += delta_exec; break; #ifdef CONFIG_SCHED_CORE case CPUTIME_FORCEIDLE: - rstatc->bstat.forceidle_sum += delta_exec; + rstatbc->bstat.forceidle_sum += delta_exec; break; #endif default: break; } - cgroup_base_stat_cputime_account_end(cgrp, rstatc, flags); + cgroup_base_stat_cputime_account_end(cgrp, rstatbc, flags); } /* @@ -574,12 +716,12 @@ void cgroup_base_stat_cputime_show(struct seq_file *seq) struct cgroup_base_stat bstat; if (cgroup_parent(cgrp)) { - cgroup_rstat_flush(cgrp); - __cgroup_rstat_lock(cgrp, -1); + css_rstat_flush(&cgrp->self); + __css_rstat_lock(&cgrp->self, -1); bstat = cgrp->bstat; cputime_adjust(&cgrp->bstat.cputime, &cgrp->prev_cputime, &bstat.cputime.utime, &bstat.cputime.stime); - __cgroup_rstat_unlock(cgrp, -1); + __css_rstat_unlock(&cgrp->self, -1); } else { root_cgroup_cputime(&bstat); } @@ -601,10 +743,10 @@ void cgroup_base_stat_cputime_show(struct seq_file *seq) cgroup_force_idle_show(seq, &bstat); } -/* Add bpf kfuncs for cgroup_rstat_updated() and cgroup_rstat_flush() */ +/* Add bpf kfuncs for css_rstat_updated() and css_rstat_flush() */ BTF_KFUNCS_START(bpf_rstat_kfunc_ids) -BTF_ID_FLAGS(func, cgroup_rstat_updated) -BTF_ID_FLAGS(func, cgroup_rstat_flush, KF_SLEEPABLE) +BTF_ID_FLAGS(func, css_rstat_updated) +BTF_ID_FLAGS(func, css_rstat_flush, KF_SLEEPABLE) BTF_KFUNCS_END(bpf_rstat_kfunc_ids) static const struct btf_kfunc_id_set bpf_rstat_kfunc_set = { diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 2d4d65f25fec..ec39e62b172e 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -582,7 +582,7 @@ static inline void memcg_rstat_updated(struct mem_cgroup *memcg, int val) if (!val) return; - cgroup_rstat_updated(memcg->css.cgroup, cpu); + css_rstat_updated(&memcg->css, cpu); statc = this_cpu_ptr(memcg->vmstats_percpu); for (; statc; statc = statc->parent) { stats_updates = READ_ONCE(statc->stats_updates) + abs(val); @@ -614,7 +614,7 @@ static void __mem_cgroup_flush_stats(struct mem_cgroup *memcg, bool force) if (mem_cgroup_is_root(memcg)) WRITE_ONCE(flush_last_time, jiffies_64); - cgroup_rstat_flush(memcg->css.cgroup); + css_rstat_flush(&memcg->css); } /* diff --git a/tools/testing/selftests/bpf/progs/btf_type_tag_percpu.c b/tools/testing/selftests/bpf/progs/btf_type_tag_percpu.c index 38f78d9345de..69f81cb555ca 100644 --- a/tools/testing/selftests/bpf/progs/btf_type_tag_percpu.c +++ b/tools/testing/selftests/bpf/progs/btf_type_tag_percpu.c @@ -30,22 +30,27 @@ int BPF_PROG(test_percpu2, struct bpf_testmod_btf_type_tag_2 *arg) /* trace_cgroup_mkdir(struct cgroup *cgrp, const char *path) * - * struct cgroup_rstat_cpu { + * struct css_rstat_cpu { * ... - * struct cgroup *updated_children; + * struct cgroup_subsys_state *updated_children; * ... * }; * - * struct cgroup { + * struct cgroup_subsys_state { + * ... + * struct css_rstat_cpu __percpu *rstat_cpu; * ... - * struct cgroup_rstat_cpu __percpu *rstat_cpu; + * }; + * + * struct cgroup { + * struct cgroup_subsys_state self; * ... * }; */ SEC("tp_btf/cgroup_mkdir") int BPF_PROG(test_percpu_load, struct cgroup *cgrp, const char *path) { - g = (__u64)cgrp->rstat_cpu->updated_children; + g = (__u64)cgrp->self.rstat_cpu->updated_children; return 0; } @@ -56,7 +61,8 @@ int BPF_PROG(test_percpu_helper, struct cgroup *cgrp, const char *path) __u32 cpu; cpu = bpf_get_smp_processor_id(); - rstat = (struct cgroup_rstat_cpu *)bpf_per_cpu_ptr(cgrp->rstat_cpu, cpu); + rstat = (struct cgroup_rstat_cpu *)bpf_per_cpu_ptr( + cgrp->self.rstat_cpu, cpu); if (rstat) { /* READ_ONCE */ *(volatile int *)rstat; diff --git a/tools/testing/selftests/bpf/progs/cgroup_hierarchical_stats.c b/tools/testing/selftests/bpf/progs/cgroup_hierarchical_stats.c index c74362854948..ff189a736ad8 100644 --- a/tools/testing/selftests/bpf/progs/cgroup_hierarchical_stats.c +++ b/tools/testing/selftests/bpf/progs/cgroup_hierarchical_stats.c @@ -37,8 +37,9 @@ struct { __type(value, struct attach_counter); } attach_counters SEC(".maps"); -extern void cgroup_rstat_updated(struct cgroup *cgrp, int cpu) __ksym; -extern void cgroup_rstat_flush(struct cgroup *cgrp) __ksym; +extern void css_rstat_updated( + struct cgroup_subsys_state *css, int cpu) __ksym; +extern void css_rstat_flush(struct cgroup_subsys_state *css) __ksym; static uint64_t cgroup_id(struct cgroup *cgrp) { @@ -75,7 +76,7 @@ int BPF_PROG(counter, struct cgroup *dst_cgrp, struct task_struct *leader, else if (create_percpu_attach_counter(cg_id, 1)) return 0; - cgroup_rstat_updated(dst_cgrp, bpf_get_smp_processor_id()); + css_rstat_updated(&dst_cgrp->self, bpf_get_smp_processor_id()); return 0; } @@ -141,7 +142,7 @@ int BPF_PROG(dumper, struct bpf_iter_meta *meta, struct cgroup *cgrp) return 1; /* Flush the stats to make sure we get the most updated numbers */ - cgroup_rstat_flush(cgrp); + css_rstat_flush(&cgrp->self); total_counter = bpf_map_lookup_elem(&attach_counters, &cg_id); if (!total_counter) { |