From: Xuehan Xu <xuxuehan@xxxxxx> this controller is supposed to facilitate limiting the metadata ops or data ops issued to the underlying cluster. Signed-off-by: Xuehan Xu <xuxuehan@xxxxxx> --- include/linux/cgroup_cephfs.h | 57 +++++ include/linux/cgroup_subsys.h | 4 + init/Kconfig | 5 + kernel/cgroup/Makefile | 1 + kernel/cgroup/cephfs.c | 398 ++++++++++++++++++++++++++++++++++ 5 files changed, 465 insertions(+) create mode 100644 include/linux/cgroup_cephfs.h create mode 100644 kernel/cgroup/cephfs.c diff --git a/include/linux/cgroup_cephfs.h b/include/linux/cgroup_cephfs.h new file mode 100644 index 000000000000..91809862b8f8 --- /dev/null +++ b/include/linux/cgroup_cephfs.h @@ -0,0 +1,57 @@ +#ifndef _CEPHFS_CGROUP_H +#define _CEPHFS_CGROUP_H + +#include <linux/cgroup.h> + +#define META_OPS_IOPS_IDX 0 +#define DATA_OPS_IOPS_IDX 0 +#define DATA_OPS_BAND_IDX 1 +#define META_OPS_TB_NUM 1 +#define DATA_OPS_TB_NUM 2 + +/* + * token bucket throttle + */ +struct token_bucket { + u64 remain; + u64 max; + u64 target_throughput; +}; + +struct token_bucket_throttle { + struct token_bucket* tb; + u64 tick_interval; + int tb_num; + struct list_head reqs_blocked; + struct mutex bucket_lock; + struct delayed_work tick_work; + unsigned long tbt_timeout; +}; + +struct queue_item { + struct list_head token_bucket_throttle_item; + u64* tokens_requested; + int tb_item_num; + struct completion throttled; + unsigned long tbt_timeout; +}; + +struct cephfscg { + struct cgroup_subsys_state css; + spinlock_t lock; + + struct token_bucket_throttle meta_ops_throttle; + struct token_bucket_throttle data_ops_throttle; +}; + +extern void schedule_token_bucket_throttle_tick(struct token_bucket_throttle* ptbt, u64 tick_interval); + +extern void token_bucket_throttle_tick(struct work_struct* work); + +extern int get_token_bucket_throttle(struct token_bucket_throttle* ptbt, struct queue_item* req); + +extern int queue_item_init(struct queue_item* qitem, struct token_bucket_throttle* ptbt, int tb_item_num); + +extern int token_bucket_throttle_init(struct token_bucket_throttle* ptbt, int token_bucket_num); + +#endif /*_CEPHFS_CGROUP_H*/ diff --git a/include/linux/cgroup_subsys.h b/include/linux/cgroup_subsys.h index acb77dcff3b4..577a276570a5 100644 --- a/include/linux/cgroup_subsys.h +++ b/include/linux/cgroup_subsys.h @@ -61,6 +61,10 @@ SUBSYS(pids) SUBSYS(rdma) #endif +#if IS_ENABLED(CONFIG_CGROUP_CEPH_FS) +SUBSYS(cephfs) +#endif + /* * The following subsystems are not supported on the default hierarchy. */ diff --git a/init/Kconfig b/init/Kconfig index 4592bf7997c0..e22f3aea9e23 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -867,6 +867,11 @@ config CGROUP_RDMA Attaching processes with active RDMA resources to the cgroup hierarchy is allowed even if can cross the hierarchy's limit. +config CGROUP_CEPH_FS + bool "cephfs controller" + help + cephfs cgroup controller + config CGROUP_FREEZER bool "Freezer controller" help diff --git a/kernel/cgroup/Makefile b/kernel/cgroup/Makefile index bfcdae896122..aaf836181f1a 100644 --- a/kernel/cgroup/Makefile +++ b/kernel/cgroup/Makefile @@ -6,3 +6,4 @@ obj-$(CONFIG_CGROUP_PIDS) += pids.o obj-$(CONFIG_CGROUP_RDMA) += rdma.o obj-$(CONFIG_CPUSETS) += cpuset.o obj-$(CONFIG_CGROUP_DEBUG) += debug.o +obj-$(CONFIG_CGROUP_CEPH_FS) += cephfs.o diff --git a/kernel/cgroup/cephfs.c b/kernel/cgroup/cephfs.c new file mode 100644 index 000000000000..65b9e9618a5d --- /dev/null +++ b/kernel/cgroup/cephfs.c @@ -0,0 +1,398 @@ +#include <linux/cgroup_cephfs.h> +#include <linux/slab.h> + +struct cephfscg cephfscg_root; + +static void put_token(struct token_bucket_throttle* ptbt, u64 tick_interval) +{ + struct token_bucket* ptb = NULL; + u64 tokens_to_put = 0; + int i = 0; + + for (i = 0; i < ptbt->tb_num; i++) { + ptb = &ptbt->tb[i]; + + if (!ptb->max) + continue; + + tokens_to_put = ptb->target_throughput * tick_interval / HZ; + + if (ptb->remain + tokens_to_put >= ptb->max) + ptb->remain = ptb->max; + else + ptb->remain += tokens_to_put; + pr_debug("%s: put_token: token bucket remain: %lld\n", __func__, ptb->remain); + } +} + +static bool should_wait(struct token_bucket_throttle* ptbt, struct queue_item* qitem) +{ + struct token_bucket* ptb = NULL; + int i = 0; + + BUG_ON(ptbt->tb_num != qitem->tb_item_num); + for (i = 0; i < ptbt->tb_num; i++) { + ptb = &ptbt->tb[i]; + + if (!ptb->max) + continue; + + if (ptb->remain < qitem->tokens_requested[i]) + return true; + } + return false; +} + +static void get_token(struct token_bucket_throttle* ptbt, struct queue_item* qitem) +{ + struct token_bucket* ptb = NULL; + int i = 0; + BUG_ON(should_wait(ptbt, qitem)); + + for (i = 0; i < ptbt->tb_num; i++) { + ptb = &ptbt->tb[i]; + if (!ptb->max) + continue; + ptb->remain -= qitem->tokens_requested[i]; + } +} + +void schedule_token_bucket_throttle_tick(struct token_bucket_throttle* ptbt, u64 tick_interval) +{ + if (tick_interval) + schedule_delayed_work(&ptbt->tick_work, tick_interval); +} +EXPORT_SYMBOL(schedule_token_bucket_throttle_tick); + +void token_bucket_throttle_tick(struct work_struct* work) +{ + struct token_bucket_throttle* ptbt = + container_of(work, struct token_bucket_throttle, tick_work.work); + struct queue_item* req = NULL, *tmp = NULL; + LIST_HEAD(reqs_to_go); + u64 tick_interval = ptbt->tick_interval; + + mutex_lock(&ptbt->bucket_lock); + put_token(ptbt, tick_interval); + if (!tick_interval) + pr_debug("%s: tick_interval set to 0, turning off the throttle, item: %p\n", __func__, req); + + list_for_each_entry_safe(req, tmp, &ptbt->reqs_blocked, token_bucket_throttle_item) { + pr_debug("%s: waiting item: %p\n", __func__, req); + if (tick_interval) { + if (should_wait(ptbt, req)) + break; + get_token(ptbt, req); + } + list_del(&req->token_bucket_throttle_item); + list_add_tail(&req->token_bucket_throttle_item, &reqs_to_go); + pr_debug("%s: tokens got for req: %p\n", __func__, req); + } + mutex_unlock(&ptbt->bucket_lock); + + list_for_each_entry_safe(req, tmp, &reqs_to_go, token_bucket_throttle_item) { + pr_debug("%s: notifying req: %p, list head: %p\n", __func__, req, &reqs_to_go); + complete_all(&req->throttled); + list_del(&req->token_bucket_throttle_item); + } + + if (tick_interval) + schedule_token_bucket_throttle_tick(ptbt, tick_interval); +} +EXPORT_SYMBOL(token_bucket_throttle_tick); + +int get_token_bucket_throttle(struct token_bucket_throttle* ptbt, struct queue_item* req) +{ + int ret = 0; + long timeleft = 0; + + mutex_lock(&ptbt->bucket_lock); + if (should_wait(ptbt, req)) { + pr_debug("%s: wait for tokens, req: %p\n", __func__, req); + list_add_tail(&req->token_bucket_throttle_item, &ptbt->reqs_blocked); + mutex_unlock(&ptbt->bucket_lock); + timeleft = wait_for_completion_killable_timeout(&req->throttled, req->tbt_timeout ?: MAX_SCHEDULE_TIMEOUT); + if (timeleft > 0) + ret = 0; + else if (!timeleft) + ret = -EIO; /* timed out */ + else { + /* killed */ + pr_debug("%s: killed, req: %p\n", __func__, req); + mutex_lock(&ptbt->bucket_lock); + list_del(&req->token_bucket_throttle_item); + mutex_unlock(&ptbt->bucket_lock); + ret = timeleft; + } + } else { + pr_debug("%s: no need to wait for tokens, going ahead, req: %p\n", __func__, req); + get_token(ptbt, req); + mutex_unlock(&ptbt->bucket_lock); + } + return ret; +} +EXPORT_SYMBOL(get_token_bucket_throttle); + +int queue_item_init(struct queue_item* qitem, struct token_bucket_throttle* ptbt, int tb_item_num) +{ + qitem->tokens_requested = kzalloc(sizeof(*qitem->tokens_requested) * tb_item_num, GFP_KERNEL); + if (!qitem->tokens_requested) + return -ENOMEM; + + qitem->tb_item_num = tb_item_num; + INIT_LIST_HEAD(&qitem->token_bucket_throttle_item); + init_completion(&qitem->throttled); + qitem->tbt_timeout = ptbt->tbt_timeout; + + return 0; +} +EXPORT_SYMBOL(queue_item_init); + +int token_bucket_throttle_init(struct token_bucket_throttle* ptbt, + int token_bucket_num) +{ + int i = 0; + + INIT_LIST_HEAD(&ptbt->reqs_blocked); + mutex_init(&ptbt->bucket_lock); + ptbt->tb_num = token_bucket_num; + ptbt->tb = kzalloc(sizeof(*ptbt->tb) * ptbt->tb_num, GFP_KERNEL); + if (!ptbt->tb) { + return -ENOMEM; + } + + for (i = 0; i < ptbt->tb_num; i++) { + ptbt->tb[i].target_throughput = 0; + ptbt->tb[i].max = 0; + } + ptbt->tick_interval = 0; + ptbt->tbt_timeout = 0; + INIT_DELAYED_WORK(&ptbt->tick_work, token_bucket_throttle_tick); + + return 0; +} +EXPORT_SYMBOL(token_bucket_throttle_init); + +static int set_throttle_params(struct token_bucket_throttle* ptbt, char* param_list) +{ + char* options = strstrip(param_list); + char* val = NULL; + int res = 0; + unsigned long interval = 0, timeout = 0, last_interval = ptbt->tick_interval; + + val = strsep(&options, ","); + if (!val) + return -EINVAL; + + res = kstrtol(val, 0, &interval); + if (res) + return res; + + val = strsep(&options, ","); + if (!val) + return -EINVAL; + + res = kstrtol(val, 0, &timeout); + if (res) + return res; + + if (last_interval && !interval) { + int i = 0; + + for (i = 0; i<ptbt->tb_num; i++) { + if (ptbt->tb[i].max) { + /* all token bucket must be unset + * before turning off the throttle */ + return -EINVAL; + } + } + } + ptbt->tick_interval = msecs_to_jiffies(interval); + ptbt->tbt_timeout = timeout; + + if (ptbt->tick_interval && !last_interval) { + schedule_token_bucket_throttle_tick(ptbt, ptbt->tick_interval); + } + + return 0; +} + +static int set_tb_params(struct token_bucket_throttle* ptbt, int tb_idx, char* param_list) +{ + char* options = strstrip(param_list); + char* val = NULL; + int res = 0; + unsigned long throughput = 0, burst = 0; + + val = strsep(&options, ","); + if (!val) + return -EINVAL; + + res = kstrtol(val, 0, &throughput); + if (res) + return res; + + val = strsep(&options, ","); + if (!val) + return -EINVAL; + + res = kstrtol(val, 0, &burst); + if (res) + return res; + + if (!(throughput && burst) && (throughput || burst)) { + /* either both or none of throughput and burst are set*/ + return -EINVAL; + } + if (throughput && !ptbt->tick_interval) { + /* all token bucket must be unset + * before turning off the throttle */ + return -EINVAL; + } + ptbt->tb[tb_idx].target_throughput = throughput; + ptbt->tb[tb_idx].max = burst; + + return 0; +} + +static ssize_t cephfscg_set_throttle_params(struct kernfs_open_file *of, + char *buf, size_t nbytes, loff_t off) +{ + const char *throttle_name; + int ret = 0; + struct cephfscg* cephfscg_p = + container_of(seq_css(of->seq_file), struct cephfscg, css); + + throttle_name = of->kn->name; + if (!strcmp(throttle_name, "cephfs.meta_ops")) { + ret = set_throttle_params(&cephfscg_p->meta_ops_throttle, buf); + } else if (!strcmp(throttle_name, "cephfs.data_ops")) { + ret = set_throttle_params(&cephfscg_p->data_ops_throttle, buf); + } else if (!strcmp(throttle_name, "cephfs.meta_ops.iops")) { + ret = set_tb_params(&cephfscg_p->meta_ops_throttle, META_OPS_IOPS_IDX, buf); + } else if (!strcmp(throttle_name, "cephfs.data_ops.iops")) { + ret = set_tb_params(&cephfscg_p->data_ops_throttle, DATA_OPS_IOPS_IDX, buf); + } else if (!strcmp(throttle_name, "cephfs.data_ops.band")) { + ret = set_tb_params(&cephfscg_p->data_ops_throttle, DATA_OPS_BAND_IDX, buf); + } + + return ret ?: nbytes; +} + +static int cephfscg_throttle_params_read(struct seq_file *sf, void *v) +{ + const char *throttle_name; + struct cephfscg* cephfscg_p = + container_of(seq_css(sf), struct cephfscg, css); + + throttle_name = ((struct kernfs_open_file*)sf->private)->kn->name; + if (!strcmp(throttle_name, "cephfs.meta_ops")) { + seq_printf(sf, "%llu,%lu\n", + cephfscg_p->meta_ops_throttle.tick_interval, + cephfscg_p->meta_ops_throttle.tbt_timeout); + } else if (!strcmp(throttle_name, "cephfs.data_ops")) { + seq_printf(sf, "%llu,%lu\n", + cephfscg_p->data_ops_throttle.tick_interval, + cephfscg_p->data_ops_throttle.tbt_timeout); + } else if (!strcmp(throttle_name, "cephfs.data_ops.iops")) { + seq_printf(sf, "%llu,%llu\n", + cephfscg_p->data_ops_throttle.tb[DATA_OPS_IOPS_IDX].target_throughput, + cephfscg_p->data_ops_throttle.tb[DATA_OPS_IOPS_IDX].max); + } else if (!strcmp(throttle_name, "cephfs.data_ops.band")) { + seq_printf(sf, "%llu,%llu\n", + cephfscg_p->data_ops_throttle.tb[DATA_OPS_BAND_IDX].target_throughput, + cephfscg_p->data_ops_throttle.tb[DATA_OPS_BAND_IDX].max); + } else if (!strcmp(throttle_name, "cephfs.meta_ops.iops")) { + seq_printf(sf, "%llu,%llu\n", + cephfscg_p->meta_ops_throttle.tb[META_OPS_IOPS_IDX].target_throughput, + cephfscg_p->meta_ops_throttle.tb[META_OPS_IOPS_IDX].max); + } + + return 0; +} + +static struct cftype cephfscg_files[] = { + { + .name = "meta_ops.iops", + .write = cephfscg_set_throttle_params, + .seq_show = cephfscg_throttle_params_read, + }, + { + .name = "meta_ops", + .write = cephfscg_set_throttle_params, + .seq_show = cephfscg_throttle_params_read, + }, + { + .name = "data_ops.iops", + .write = cephfscg_set_throttle_params, + .seq_show = cephfscg_throttle_params_read, + }, + { + .name = "data_ops.band", + .write = cephfscg_set_throttle_params, + .seq_show = cephfscg_throttle_params_read, + }, + { + .name = "data_ops", + .write = cephfscg_set_throttle_params, + .seq_show = cephfscg_throttle_params_read, + }, + { } +}; + +static struct cgroup_subsys_state * +cephfscg_css_alloc(struct cgroup_subsys_state *parent_css) { + + struct cephfscg* cephfscg_p = NULL; + struct cgroup_subsys_state *ret = NULL; + int r = 0; + + if (!parent_css) { + cephfscg_p = &cephfscg_root; + } else { + cephfscg_p = kzalloc(sizeof(*cephfscg_p), GFP_KERNEL); + if (!cephfscg_p) { + ret = ERR_PTR(-ENOMEM); + goto err; + } + } + + spin_lock_init(&cephfscg_p->lock); + + r = token_bucket_throttle_init(&cephfscg_p->meta_ops_throttle, 1); + if (r) { + ret = ERR_PTR(r); + goto err; + } + + r = token_bucket_throttle_init(&cephfscg_p->data_ops_throttle, 2); + if (r) { + ret = ERR_PTR(r); + goto err; + } + + return &cephfscg_p->css; +err: + return ret; +} + +static void cephfscg_css_free(struct cgroup_subsys_state *css) { + struct cephfscg* cephfscg_p = + css ? container_of(css, struct cephfscg, css) : NULL; + + cancel_delayed_work_sync(&cephfscg_p->meta_ops_throttle.tick_work); + cancel_delayed_work_sync(&cephfscg_p->data_ops_throttle.tick_work); + + kfree(cephfscg_p->meta_ops_throttle.tb); + kfree(cephfscg_p->data_ops_throttle.tb); + + kfree(cephfscg_p); +} + +struct cgroup_subsys cephfs_cgrp_subsys = { + .css_alloc = cephfscg_css_alloc, + .css_free = cephfscg_css_free, + .dfl_cftypes = cephfscg_files, + .legacy_cftypes = cephfscg_files, +}; +EXPORT_SYMBOL_GPL(cephfs_cgrp_subsys); -- 2.20.1