OSCL-LXR linux-6.0.1/​mm/​hugetlb_cgroup.c	Source navigation Diff markup Identifier search General search
	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 /*
  *
  * Copyright IBM Corporation, 2012
  * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
  *
  * Cgroup v2
  * Copyright (C) 2019 Red Hat, Inc.
  * Author: Giuseppe Scrivano <gscrivan@redhat.com>
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms of version 2.1 of the GNU Lesser General Public License
  * as published by the Free Software Foundation.
  *
  * This program is distributed in the hope that it would be useful, but
  * WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  *
  */
 
 #include <linux/cgroup.h>
 #include <linux/page_counter.h>
 #include <linux/slab.h>
 #include <linux/hugetlb.h>
 #include <linux/hugetlb_cgroup.h>
 
 #define MEMFILE_PRIVATE(x, val) (((x) << 16) | (val))
 #define MEMFILE_IDX(val)    (((val) >> 16) & 0xffff)
 #define MEMFILE_ATTR(val)   ((val) & 0xffff)
 
 static struct hugetlb_cgroup *root_h_cgroup __read_mostly;
 
 static inline struct page_counter *
 __hugetlb_cgroup_counter_from_cgroup(struct hugetlb_cgroup *h_cg, int idx,
                      bool rsvd)
 {
     if (rsvd)
         return &h_cg->rsvd_hugepage[idx];
     return &h_cg->hugepage[idx];
 }
 
 static inline struct page_counter *
 hugetlb_cgroup_counter_from_cgroup(struct hugetlb_cgroup *h_cg, int idx)
 {
     return __hugetlb_cgroup_counter_from_cgroup(h_cg, idx, false);
 }
 
 static inline struct page_counter *
 hugetlb_cgroup_counter_from_cgroup_rsvd(struct hugetlb_cgroup *h_cg, int idx)
 {
     return __hugetlb_cgroup_counter_from_cgroup(h_cg, idx, true);
 }
 
 static inline
 struct hugetlb_cgroup *hugetlb_cgroup_from_css(struct cgroup_subsys_state *s)
 {
     return s ? container_of(s, struct hugetlb_cgroup, css) : NULL;
 }
 
 static inline
 struct hugetlb_cgroup *hugetlb_cgroup_from_task(struct task_struct *task)
 {
     return hugetlb_cgroup_from_css(task_css(task, hugetlb_cgrp_id));
 }
 
 static inline bool hugetlb_cgroup_is_root(struct hugetlb_cgroup *h_cg)
 {
     return (h_cg == root_h_cgroup);
 }
 
 static inline struct hugetlb_cgroup *
 parent_hugetlb_cgroup(struct hugetlb_cgroup *h_cg)
 {
     return hugetlb_cgroup_from_css(h_cg->css.parent);
 }
 
 static inline bool hugetlb_cgroup_have_usage(struct hugetlb_cgroup *h_cg)
 {
     int idx;
 
     for (idx = 0; idx < hugetlb_max_hstate; idx++) {
         if (page_counter_read(
                 hugetlb_cgroup_counter_from_cgroup(h_cg, idx)))
             return true;
     }
     return false;
 }
 
 static void hugetlb_cgroup_init(struct hugetlb_cgroup *h_cgroup,
                 struct hugetlb_cgroup *parent_h_cgroup)
 {
     int idx;
 
     for (idx = 0; idx < HUGE_MAX_HSTATE; idx++) {
         struct page_counter *fault_parent = NULL;
         struct page_counter *rsvd_parent = NULL;
         unsigned long limit;
         int ret;
 
         if (parent_h_cgroup) {
             fault_parent = hugetlb_cgroup_counter_from_cgroup(
                 parent_h_cgroup, idx);
             rsvd_parent = hugetlb_cgroup_counter_from_cgroup_rsvd(
                 parent_h_cgroup, idx);
         }
         page_counter_init(hugetlb_cgroup_counter_from_cgroup(h_cgroup,
                                      idx),
                   fault_parent);
         page_counter_init(
             hugetlb_cgroup_counter_from_cgroup_rsvd(h_cgroup, idx),
             rsvd_parent);
 
         limit = round_down(PAGE_COUNTER_MAX,
                    pages_per_huge_page(&hstates[idx]));
 
         ret = page_counter_set_max(
             hugetlb_cgroup_counter_from_cgroup(h_cgroup, idx),
             limit);
         VM_BUG_ON(ret);
         ret = page_counter_set_max(
             hugetlb_cgroup_counter_from_cgroup_rsvd(h_cgroup, idx),
             limit);
         VM_BUG_ON(ret);
     }
 }
 
 static void hugetlb_cgroup_free(struct hugetlb_cgroup *h_cgroup)
 {
     int node;
 
     for_each_node(node)
         kfree(h_cgroup->nodeinfo[node]);
     kfree(h_cgroup);
 }
 
 static struct cgroup_subsys_state *
 hugetlb_cgroup_css_alloc(struct cgroup_subsys_state *parent_css)
 {
     struct hugetlb_cgroup *parent_h_cgroup = hugetlb_cgroup_from_css(parent_css);
     struct hugetlb_cgroup *h_cgroup;
     int node;
 
     h_cgroup = kzalloc(struct_size(h_cgroup, nodeinfo, nr_node_ids),
                GFP_KERNEL);
 
     if (!h_cgroup)
         return ERR_PTR(-ENOMEM);
 
     if (!parent_h_cgroup)
         root_h_cgroup = h_cgroup;
 
     /*
      * TODO: this routine can waste much memory for nodes which will
      * never be onlined. It's better to use memory hotplug callback
      * function.
      */
     for_each_node(node) {
         /* Set node_to_alloc to -1 for offline nodes. */
         int node_to_alloc =
             node_state(node, N_NORMAL_MEMORY) ? node : -1;
         h_cgroup->nodeinfo[node] =
             kzalloc_node(sizeof(struct hugetlb_cgroup_per_node),
                      GFP_KERNEL, node_to_alloc);
         if (!h_cgroup->nodeinfo[node])
             goto fail_alloc_nodeinfo;
     }
 
     hugetlb_cgroup_init(h_cgroup, parent_h_cgroup);
     return &h_cgroup->css;
 
 fail_alloc_nodeinfo:
     hugetlb_cgroup_free(h_cgroup);
     return ERR_PTR(-ENOMEM);
 }
 
 static void hugetlb_cgroup_css_free(struct cgroup_subsys_state *css)
 {
     hugetlb_cgroup_free(hugetlb_cgroup_from_css(css));
 }
 
 /*
  * Should be called with hugetlb_lock held.
  * Since we are holding hugetlb_lock, pages cannot get moved from
  * active list or uncharged from the cgroup, So no need to get
  * page reference and test for page active here. This function
  * cannot fail.
  */
 static void hugetlb_cgroup_move_parent(int idx, struct hugetlb_cgroup *h_cg,
                        struct page *page)
 {
     unsigned int nr_pages;
     struct page_counter *counter;
     struct hugetlb_cgroup *page_hcg;
     struct hugetlb_cgroup *parent = parent_hugetlb_cgroup(h_cg);
 
     page_hcg = hugetlb_cgroup_from_page(page);
     /*
      * We can have pages in active list without any cgroup
      * ie, hugepage with less than 3 pages. We can safely
      * ignore those pages.
      */
     if (!page_hcg || page_hcg != h_cg)
         goto out;
 
     nr_pages = compound_nr(page);
     if (!parent) {
         parent = root_h_cgroup;
         /* root has no limit */
         page_counter_charge(&parent->hugepage[idx], nr_pages);
     }
     counter = &h_cg->hugepage[idx];
     /* Take the pages off the local counter */
     page_counter_cancel(counter, nr_pages);
 
     set_hugetlb_cgroup(page, parent);
 out:
     return;
 }
 
 /*
  * Force the hugetlb cgroup to empty the hugetlb resources by moving them to
  * the parent cgroup.
  */
 static void hugetlb_cgroup_css_offline(struct cgroup_subsys_state *css)
 {
     struct hugetlb_cgroup *h_cg = hugetlb_cgroup_from_css(css);
     struct hstate *h;
     struct page *page;
     int idx;
 
     do {
         idx = 0;
         for_each_hstate(h) {
             spin_lock_irq(&hugetlb_lock);
             list_for_each_entry(page, &h->hugepage_activelist, lru)
                 hugetlb_cgroup_move_parent(idx, h_cg, page);
 
             spin_unlock_irq(&hugetlb_lock);
             idx++;
         }
         cond_resched();
     } while (hugetlb_cgroup_have_usage(h_cg));
 }
 
 static inline void hugetlb_event(struct hugetlb_cgroup *hugetlb, int idx,
                  enum hugetlb_memory_event event)
 {
     atomic_long_inc(&hugetlb->events_local[idx][event]);
     cgroup_file_notify(&hugetlb->events_local_file[idx]);
 
     do {
         atomic_long_inc(&hugetlb->events[idx][event]);
         cgroup_file_notify(&hugetlb->events_file[idx]);
     } while ((hugetlb = parent_hugetlb_cgroup(hugetlb)) &&
          !hugetlb_cgroup_is_root(hugetlb));
 }
 
 static int __hugetlb_cgroup_charge_cgroup(int idx, unsigned long nr_pages,
                       struct hugetlb_cgroup **ptr,
                       bool rsvd)
 {
     int ret = 0;
     struct page_counter *counter;
     struct hugetlb_cgroup *h_cg = NULL;
 
     if (hugetlb_cgroup_disabled())
         goto done;
     /*
      * We don't charge any cgroup if the compound page have less
      * than 3 pages.
      */
     if (huge_page_order(&hstates[idx]) < HUGETLB_CGROUP_MIN_ORDER)
         goto done;
 again:
     rcu_read_lock();
     h_cg = hugetlb_cgroup_from_task(current);
     if (!css_tryget(&h_cg->css)) {
         rcu_read_unlock();
         goto again;
     }
     rcu_read_unlock();
 
     if (!page_counter_try_charge(
             __hugetlb_cgroup_counter_from_cgroup(h_cg, idx, rsvd),
             nr_pages, &counter)) {
         ret = -ENOMEM;
         hugetlb_event(h_cg, idx, HUGETLB_MAX);
         css_put(&h_cg->css);
         goto done;
     }
     /* Reservations take a reference to the css because they do not get
      * reparented.
      */
     if (!rsvd)
         css_put(&h_cg->css);
 done:
     *ptr = h_cg;
     return ret;
 }
 
 int hugetlb_cgroup_charge_cgroup(int idx, unsigned long nr_pages,
                  struct hugetlb_cgroup **ptr)
 {
     return __hugetlb_cgroup_charge_cgroup(idx, nr_pages, ptr, false);
 }
 
 int hugetlb_cgroup_charge_cgroup_rsvd(int idx, unsigned long nr_pages,
                       struct hugetlb_cgroup **ptr)
 {
     return __hugetlb_cgroup_charge_cgroup(idx, nr_pages, ptr, true);
 }
 
 /* Should be called with hugetlb_lock held */
 static void __hugetlb_cgroup_commit_charge(int idx, unsigned long nr_pages,
                        struct hugetlb_cgroup *h_cg,
                        struct page *page, bool rsvd)
 {
     if (hugetlb_cgroup_disabled() || !h_cg)
         return;
 
     __set_hugetlb_cgroup(page, h_cg, rsvd);
     if (!rsvd) {
         unsigned long usage =
             h_cg->nodeinfo[page_to_nid(page)]->usage[idx];
         /*
          * This write is not atomic due to fetching usage and writing
          * to it, but that's fine because we call this with
          * hugetlb_lock held anyway.
          */
         WRITE_ONCE(h_cg->nodeinfo[page_to_nid(page)]->usage[idx],
                usage + nr_pages);
     }
 }
 
 void hugetlb_cgroup_commit_charge(int idx, unsigned long nr_pages,
                   struct hugetlb_cgroup *h_cg,
                   struct page *page)
 {
     __hugetlb_cgroup_commit_charge(idx, nr_pages, h_cg, page, false);
 }
 
 void hugetlb_cgroup_commit_charge_rsvd(int idx, unsigned long nr_pages,
                        struct hugetlb_cgroup *h_cg,
                        struct page *page)
 {
     __hugetlb_cgroup_commit_charge(idx, nr_pages, h_cg, page, true);
 }
 
 /*
  * Should be called with hugetlb_lock held
  */
 static void __hugetlb_cgroup_uncharge_page(int idx, unsigned long nr_pages,
                        struct page *page, bool rsvd)
 {
     struct hugetlb_cgroup *h_cg;
 
     if (hugetlb_cgroup_disabled())
         return;
     lockdep_assert_held(&hugetlb_lock);
     h_cg = __hugetlb_cgroup_from_page(page, rsvd);
     if (unlikely(!h_cg))
         return;
     __set_hugetlb_cgroup(page, NULL, rsvd);
 
     page_counter_uncharge(__hugetlb_cgroup_counter_from_cgroup(h_cg, idx,
                                    rsvd),
                   nr_pages);
 
     if (rsvd)
         css_put(&h_cg->css);
     else {
         unsigned long usage =
             h_cg->nodeinfo[page_to_nid(page)]->usage[idx];
         /*
          * This write is not atomic due to fetching usage and writing
          * to it, but that's fine because we call this with
          * hugetlb_lock held anyway.
          */
         WRITE_ONCE(h_cg->nodeinfo[page_to_nid(page)]->usage[idx],
                usage - nr_pages);
     }
 }
 
 void hugetlb_cgroup_uncharge_page(int idx, unsigned long nr_pages,
                   struct page *page)
 {
     __hugetlb_cgroup_uncharge_page(idx, nr_pages, page, false);
 }
 
 void hugetlb_cgroup_uncharge_page_rsvd(int idx, unsigned long nr_pages,
                        struct page *page)
 {
     __hugetlb_cgroup_uncharge_page(idx, nr_pages, page, true);
 }
 
 static void __hugetlb_cgroup_uncharge_cgroup(int idx, unsigned long nr_pages,
                          struct hugetlb_cgroup *h_cg,
                          bool rsvd)
 {
     if (hugetlb_cgroup_disabled() || !h_cg)
         return;
 
     if (huge_page_order(&hstates[idx]) < HUGETLB_CGROUP_MIN_ORDER)
         return;
 
     page_counter_uncharge(__hugetlb_cgroup_counter_from_cgroup(h_cg, idx,
                                    rsvd),
                   nr_pages);
 
     if (rsvd)
         css_put(&h_cg->css);
 }
 
 void hugetlb_cgroup_uncharge_cgroup(int idx, unsigned long nr_pages,
                     struct hugetlb_cgroup *h_cg)
 {
     __hugetlb_cgroup_uncharge_cgroup(idx, nr_pages, h_cg, false);
 }
 
 void hugetlb_cgroup_uncharge_cgroup_rsvd(int idx, unsigned long nr_pages,
                      struct hugetlb_cgroup *h_cg)
 {
     __hugetlb_cgroup_uncharge_cgroup(idx, nr_pages, h_cg, true);
 }
 
 void hugetlb_cgroup_uncharge_counter(struct resv_map *resv, unsigned long start,
                      unsigned long end)
 {
     if (hugetlb_cgroup_disabled() || !resv || !resv->reservation_counter ||
         !resv->css)
         return;
 
     page_counter_uncharge(resv->reservation_counter,
                   (end - start) * resv->pages_per_hpage);
     css_put(resv->css);
 }
 
 void hugetlb_cgroup_uncharge_file_region(struct resv_map *resv,
                      struct file_region *rg,
                      unsigned long nr_pages,
                      bool region_del)
 {
     if (hugetlb_cgroup_disabled() || !resv || !rg || !nr_pages)
         return;
 
     if (rg->reservation_counter && resv->pages_per_hpage && nr_pages > 0 &&
         !resv->reservation_counter) {
         page_counter_uncharge(rg->reservation_counter,
                       nr_pages * resv->pages_per_hpage);
         /*
          * Only do css_put(rg->css) when we delete the entire region
          * because one file_region must hold exactly one css reference.
          */
         if (region_del)
             css_put(rg->css);
     }
 }
 
 enum {
     RES_USAGE,
     RES_RSVD_USAGE,
     RES_LIMIT,
     RES_RSVD_LIMIT,
     RES_MAX_USAGE,
     RES_RSVD_MAX_USAGE,
     RES_FAILCNT,
     RES_RSVD_FAILCNT,
 };
 
 static int hugetlb_cgroup_read_numa_stat(struct seq_file *seq, void *dummy)
 {
     int nid;
     struct cftype *cft = seq_cft(seq);
     int idx = MEMFILE_IDX(cft->private);
     bool legacy = MEMFILE_ATTR(cft->private);
     struct hugetlb_cgroup *h_cg = hugetlb_cgroup_from_css(seq_css(seq));
     struct cgroup_subsys_state *css;
     unsigned long usage;
 
     if (legacy) {
         /* Add up usage across all nodes for the non-hierarchical total. */
         usage = 0;
         for_each_node_state(nid, N_MEMORY)
             usage += READ_ONCE(h_cg->nodeinfo[nid]->usage[idx]);
         seq_printf(seq, "total=%lu", usage * PAGE_SIZE);
 
         /* Simply print the per-node usage for the non-hierarchical total. */
         for_each_node_state(nid, N_MEMORY)
             seq_printf(seq, " N%d=%lu", nid,
                    READ_ONCE(h_cg->nodeinfo[nid]->usage[idx]) *
                        PAGE_SIZE);
         seq_putc(seq, '\n');
     }
 
     /*
      * The hierarchical total is pretty much the value recorded by the
      * counter, so use that.
      */
     seq_printf(seq, "%stotal=%lu", legacy ? "hierarchical_" : "",
            page_counter_read(&h_cg->hugepage[idx]) * PAGE_SIZE);
 
     /*
      * For each node, transverse the css tree to obtain the hierarchical
      * node usage.
      */
     for_each_node_state(nid, N_MEMORY) {
         usage = 0;
         rcu_read_lock();
         css_for_each_descendant_pre(css, &h_cg->css) {
             usage += READ_ONCE(hugetlb_cgroup_from_css(css)
                            ->nodeinfo[nid]
                            ->usage[idx]);
         }
         rcu_read_unlock();
         seq_printf(seq, " N%d=%lu", nid, usage * PAGE_SIZE);
     }
 
     seq_putc(seq, '\n');
 
     return 0;
 }
 
 static u64 hugetlb_cgroup_read_u64(struct cgroup_subsys_state *css,
                    struct cftype *cft)
 {
     struct page_counter *counter;
     struct page_counter *rsvd_counter;
     struct hugetlb_cgroup *h_cg = hugetlb_cgroup_from_css(css);
 
     counter = &h_cg->hugepage[MEMFILE_IDX(cft->private)];
     rsvd_counter = &h_cg->rsvd_hugepage[MEMFILE_IDX(cft->private)];
 
     switch (MEMFILE_ATTR(cft->private)) {
     case RES_USAGE:
         return (u64)page_counter_read(counter) * PAGE_SIZE;
     case RES_RSVD_USAGE:
         return (u64)page_counter_read(rsvd_counter) * PAGE_SIZE;
     case RES_LIMIT:
         return (u64)counter->max * PAGE_SIZE;
     case RES_RSVD_LIMIT:
         return (u64)rsvd_counter->max * PAGE_SIZE;
     case RES_MAX_USAGE:
         return (u64)counter->watermark * PAGE_SIZE;
     case RES_RSVD_MAX_USAGE:
         return (u64)rsvd_counter->watermark * PAGE_SIZE;
     case RES_FAILCNT:
         return counter->failcnt;
     case RES_RSVD_FAILCNT:
         return rsvd_counter->failcnt;
     default:
         BUG();
     }
 }
 
 static int hugetlb_cgroup_read_u64_max(struct seq_file *seq, void *v)
 {
     int idx;
     u64 val;
     struct cftype *cft = seq_cft(seq);
     unsigned long limit;
     struct page_counter *counter;
     struct hugetlb_cgroup *h_cg = hugetlb_cgroup_from_css(seq_css(seq));
 
     idx = MEMFILE_IDX(cft->private);
     counter = &h_cg->hugepage[idx];
 
     limit = round_down(PAGE_COUNTER_MAX,
                pages_per_huge_page(&hstates[idx]));
 
     switch (MEMFILE_ATTR(cft->private)) {
     case RES_RSVD_USAGE:
         counter = &h_cg->rsvd_hugepage[idx];
         fallthrough;
     case RES_USAGE:
         val = (u64)page_counter_read(counter);
         seq_printf(seq, "%llu\n", val * PAGE_SIZE);
         break;
     case RES_RSVD_LIMIT:
         counter = &h_cg->rsvd_hugepage[idx];
         fallthrough;
     case RES_LIMIT:
         val = (u64)counter->max;
         if (val == limit)
             seq_puts(seq, "max\n");
         else
             seq_printf(seq, "%llu\n", val * PAGE_SIZE);
         break;
     default:
         BUG();
     }
 
     return 0;
 }
 
 static DEFINE_MUTEX(hugetlb_limit_mutex);
 
 static ssize_t hugetlb_cgroup_write(struct kernfs_open_file *of,
                     char *buf, size_t nbytes, loff_t off,
                     const char *max)
 {
     int ret, idx;
     unsigned long nr_pages;
     struct hugetlb_cgroup *h_cg = hugetlb_cgroup_from_css(of_css(of));
     bool rsvd = false;
 
     if (hugetlb_cgroup_is_root(h_cg)) /* Can't set limit on root */
         return -EINVAL;
 
     buf = strstrip(buf);
     ret = page_counter_memparse(buf, max, &nr_pages);
     if (ret)
         return ret;
 
     idx = MEMFILE_IDX(of_cft(of)->private);
     nr_pages = round_down(nr_pages, pages_per_huge_page(&hstates[idx]));
 
     switch (MEMFILE_ATTR(of_cft(of)->private)) {
     case RES_RSVD_LIMIT:
         rsvd = true;
         fallthrough;
     case RES_LIMIT:
         mutex_lock(&hugetlb_limit_mutex);
         ret = page_counter_set_max(
             __hugetlb_cgroup_counter_from_cgroup(h_cg, idx, rsvd),
             nr_pages);
         mutex_unlock(&hugetlb_limit_mutex);
         break;
     default:
         ret = -EINVAL;
         break;
     }
     return ret ?: nbytes;
 }
 
 static ssize_t hugetlb_cgroup_write_legacy(struct kernfs_open_file *of,
                        char *buf, size_t nbytes, loff_t off)
 {
     return hugetlb_cgroup_write(of, buf, nbytes, off, "-1");
 }
 
 static ssize_t hugetlb_cgroup_write_dfl(struct kernfs_open_file *of,
                     char *buf, size_t nbytes, loff_t off)
 {
     return hugetlb_cgroup_write(of, buf, nbytes, off, "max");
 }
 
 static ssize_t hugetlb_cgroup_reset(struct kernfs_open_file *of,
                     char *buf, size_t nbytes, loff_t off)
 {
     int ret = 0;
     struct page_counter *counter, *rsvd_counter;
     struct hugetlb_cgroup *h_cg = hugetlb_cgroup_from_css(of_css(of));
 
     counter = &h_cg->hugepage[MEMFILE_IDX(of_cft(of)->private)];
     rsvd_counter = &h_cg->rsvd_hugepage[MEMFILE_IDX(of_cft(of)->private)];
 
     switch (MEMFILE_ATTR(of_cft(of)->private)) {
     case RES_MAX_USAGE:
         page_counter_reset_watermark(counter);
         break;
     case RES_RSVD_MAX_USAGE:
         page_counter_reset_watermark(rsvd_counter);
         break;
     case RES_FAILCNT:
         counter->failcnt = 0;
         break;
     case RES_RSVD_FAILCNT:
         rsvd_counter->failcnt = 0;
         break;
     default:
         ret = -EINVAL;
         break;
     }
     return ret ?: nbytes;
 }
 
 static char *mem_fmt(char *buf, int size, unsigned long hsize)
 {
     if (hsize >= (1UL << 30))
         snprintf(buf, size, "%luGB", hsize >> 30);
     else if (hsize >= (1UL << 20))
         snprintf(buf, size, "%luMB", hsize >> 20);
     else
         snprintf(buf, size, "%luKB", hsize >> 10);
     return buf;
 }
 
 static int __hugetlb_events_show(struct seq_file *seq, bool local)
 {
     int idx;
     long max;
     struct cftype *cft = seq_cft(seq);
     struct hugetlb_cgroup *h_cg = hugetlb_cgroup_from_css(seq_css(seq));
 
     idx = MEMFILE_IDX(cft->private);
 
     if (local)
         max = atomic_long_read(&h_cg->events_local[idx][HUGETLB_MAX]);
     else
         max = atomic_long_read(&h_cg->events[idx][HUGETLB_MAX]);
 
     seq_printf(seq, "max %lu\n", max);
 
     return 0;
 }
 
 static int hugetlb_events_show(struct seq_file *seq, void *v)
 {
     return __hugetlb_events_show(seq, false);
 }
 
 static int hugetlb_events_local_show(struct seq_file *seq, void *v)
 {
     return __hugetlb_events_show(seq, true);
 }
 
 static void __init __hugetlb_cgroup_file_dfl_init(int idx)
 {
     char buf[32];
     struct cftype *cft;
     struct hstate *h = &hstates[idx];
 
     /* format the size */
     mem_fmt(buf, sizeof(buf), huge_page_size(h));
 
     /* Add the limit file */
     cft = &h->cgroup_files_dfl[0];
     snprintf(cft->name, MAX_CFTYPE_NAME, "%s.max", buf);
     cft->private = MEMFILE_PRIVATE(idx, RES_LIMIT);
     cft->seq_show = hugetlb_cgroup_read_u64_max;
     cft->write = hugetlb_cgroup_write_dfl;
     cft->flags = CFTYPE_NOT_ON_ROOT;
 
     /* Add the reservation limit file */
     cft = &h->cgroup_files_dfl[1];
     snprintf(cft->name, MAX_CFTYPE_NAME, "%s.rsvd.max", buf);
     cft->private = MEMFILE_PRIVATE(idx, RES_RSVD_LIMIT);
     cft->seq_show = hugetlb_cgroup_read_u64_max;
     cft->write = hugetlb_cgroup_write_dfl;
     cft->flags = CFTYPE_NOT_ON_ROOT;
 
     /* Add the current usage file */
     cft = &h->cgroup_files_dfl[2];
     snprintf(cft->name, MAX_CFTYPE_NAME, "%s.current", buf);
     cft->private = MEMFILE_PRIVATE(idx, RES_USAGE);
     cft->seq_show = hugetlb_cgroup_read_u64_max;
     cft->flags = CFTYPE_NOT_ON_ROOT;
 
     /* Add the current reservation usage file */
     cft = &h->cgroup_files_dfl[3];
     snprintf(cft->name, MAX_CFTYPE_NAME, "%s.rsvd.current", buf);
     cft->private = MEMFILE_PRIVATE(idx, RES_RSVD_USAGE);
     cft->seq_show = hugetlb_cgroup_read_u64_max;
     cft->flags = CFTYPE_NOT_ON_ROOT;
 
     /* Add the events file */
     cft = &h->cgroup_files_dfl[4];
     snprintf(cft->name, MAX_CFTYPE_NAME, "%s.events", buf);
     cft->private = MEMFILE_PRIVATE(idx, 0);
     cft->seq_show = hugetlb_events_show;
     cft->file_offset = offsetof(struct hugetlb_cgroup, events_file[idx]);
     cft->flags = CFTYPE_NOT_ON_ROOT;
 
     /* Add the events.local file */
     cft = &h->cgroup_files_dfl[5];
     snprintf(cft->name, MAX_CFTYPE_NAME, "%s.events.local", buf);
     cft->private = MEMFILE_PRIVATE(idx, 0);
     cft->seq_show = hugetlb_events_local_show;
     cft->file_offset = offsetof(struct hugetlb_cgroup,
                     events_local_file[idx]);
     cft->flags = CFTYPE_NOT_ON_ROOT;
 
     /* Add the numa stat file */
     cft = &h->cgroup_files_dfl[6];
     snprintf(cft->name, MAX_CFTYPE_NAME, "%s.numa_stat", buf);
     cft->private = MEMFILE_PRIVATE(idx, 0);
     cft->seq_show = hugetlb_cgroup_read_numa_stat;
     cft->flags = CFTYPE_NOT_ON_ROOT;
 
     /* NULL terminate the last cft */
     cft = &h->cgroup_files_dfl[7];
     memset(cft, 0, sizeof(*cft));
 
     WARN_ON(cgroup_add_dfl_cftypes(&hugetlb_cgrp_subsys,
                        h->cgroup_files_dfl));
 }
 
 static void __init __hugetlb_cgroup_file_legacy_init(int idx)
 {
     char buf[32];
     struct cftype *cft;
     struct hstate *h = &hstates[idx];
 
     /* format the size */
     mem_fmt(buf, sizeof(buf), huge_page_size(h));
 
     /* Add the limit file */
     cft = &h->cgroup_files_legacy[0];
     snprintf(cft->name, MAX_CFTYPE_NAME, "%s.limit_in_bytes", buf);
     cft->private = MEMFILE_PRIVATE(idx, RES_LIMIT);
     cft->read_u64 = hugetlb_cgroup_read_u64;
     cft->write = hugetlb_cgroup_write_legacy;
 
     /* Add the reservation limit file */
     cft = &h->cgroup_files_legacy[1];
     snprintf(cft->name, MAX_CFTYPE_NAME, "%s.rsvd.limit_in_bytes", buf);
     cft->private = MEMFILE_PRIVATE(idx, RES_RSVD_LIMIT);
     cft->read_u64 = hugetlb_cgroup_read_u64;
     cft->write = hugetlb_cgroup_write_legacy;
 
     /* Add the usage file */
     cft = &h->cgroup_files_legacy[2];
     snprintf(cft->name, MAX_CFTYPE_NAME, "%s.usage_in_bytes", buf);
     cft->private = MEMFILE_PRIVATE(idx, RES_USAGE);
     cft->read_u64 = hugetlb_cgroup_read_u64;
 
     /* Add the reservation usage file */
     cft = &h->cgroup_files_legacy[3];
     snprintf(cft->name, MAX_CFTYPE_NAME, "%s.rsvd.usage_in_bytes", buf);
     cft->private = MEMFILE_PRIVATE(idx, RES_RSVD_USAGE);
     cft->read_u64 = hugetlb_cgroup_read_u64;
 
     /* Add the MAX usage file */
     cft = &h->cgroup_files_legacy[4];
     snprintf(cft->name, MAX_CFTYPE_NAME, "%s.max_usage_in_bytes", buf);
     cft->private = MEMFILE_PRIVATE(idx, RES_MAX_USAGE);
     cft->write = hugetlb_cgroup_reset;
     cft->read_u64 = hugetlb_cgroup_read_u64;
 
     /* Add the MAX reservation usage file */
     cft = &h->cgroup_files_legacy[5];
     snprintf(cft->name, MAX_CFTYPE_NAME, "%s.rsvd.max_usage_in_bytes", buf);
     cft->private = MEMFILE_PRIVATE(idx, RES_RSVD_MAX_USAGE);
     cft->write = hugetlb_cgroup_reset;
     cft->read_u64 = hugetlb_cgroup_read_u64;
 
     /* Add the failcntfile */
     cft = &h->cgroup_files_legacy[6];
     snprintf(cft->name, MAX_CFTYPE_NAME, "%s.failcnt", buf);
     cft->private = MEMFILE_PRIVATE(idx, RES_FAILCNT);
     cft->write = hugetlb_cgroup_reset;
     cft->read_u64 = hugetlb_cgroup_read_u64;
 
     /* Add the reservation failcntfile */
     cft = &h->cgroup_files_legacy[7];
     snprintf(cft->name, MAX_CFTYPE_NAME, "%s.rsvd.failcnt", buf);
     cft->private = MEMFILE_PRIVATE(idx, RES_RSVD_FAILCNT);
     cft->write = hugetlb_cgroup_reset;
     cft->read_u64 = hugetlb_cgroup_read_u64;
 
     /* Add the numa stat file */
     cft = &h->cgroup_files_legacy[8];
     snprintf(cft->name, MAX_CFTYPE_NAME, "%s.numa_stat", buf);
     cft->private = MEMFILE_PRIVATE(idx, 1);
     cft->seq_show = hugetlb_cgroup_read_numa_stat;
 
     /* NULL terminate the last cft */
     cft = &h->cgroup_files_legacy[9];
     memset(cft, 0, sizeof(*cft));
 
     WARN_ON(cgroup_add_legacy_cftypes(&hugetlb_cgrp_subsys,
                       h->cgroup_files_legacy));
 }
 
 static void __init __hugetlb_cgroup_file_init(int idx)
 {
     __hugetlb_cgroup_file_dfl_init(idx);
     __hugetlb_cgroup_file_legacy_init(idx);
 }
 
 void __init hugetlb_cgroup_file_init(void)
 {
     struct hstate *h;
 
     for_each_hstate(h) {
         /*
          * Add cgroup control files only if the huge page consists
          * of more than two normal pages. This is because we use
          * page[2].private for storing cgroup details.
          */
         if (huge_page_order(h) >= HUGETLB_CGROUP_MIN_ORDER)
             __hugetlb_cgroup_file_init(hstate_index(h));
     }
 }
 
 /*
  * hugetlb_lock will make sure a parallel cgroup rmdir won't happen
  * when we migrate hugepages
  */
 void hugetlb_cgroup_migrate(struct page *oldhpage, struct page *newhpage)
 {
     struct hugetlb_cgroup *h_cg;
     struct hugetlb_cgroup *h_cg_rsvd;
     struct hstate *h = page_hstate(oldhpage);
 
     if (hugetlb_cgroup_disabled())
         return;
 
     spin_lock_irq(&hugetlb_lock);
     h_cg = hugetlb_cgroup_from_page(oldhpage);
     h_cg_rsvd = hugetlb_cgroup_from_page_rsvd(oldhpage);
     set_hugetlb_cgroup(oldhpage, NULL);
     set_hugetlb_cgroup_rsvd(oldhpage, NULL);
 
     /* move the h_cg details to new cgroup */
     set_hugetlb_cgroup(newhpage, h_cg);
     set_hugetlb_cgroup_rsvd(newhpage, h_cg_rsvd);
     list_move(&newhpage->lru, &h->hugepage_activelist);
     spin_unlock_irq(&hugetlb_lock);
     return;
 }
 
 static struct cftype hugetlb_files[] = {
     {} /* terminate */
 };
 
 struct cgroup_subsys hugetlb_cgrp_subsys = {
     .css_alloc  = hugetlb_cgroup_css_alloc,
     .css_offline    = hugetlb_cgroup_css_offline,
     .css_free   = hugetlb_cgroup_css_free,
     .dfl_cftypes    = hugetlb_files,
     .legacy_cftypes = hugetlb_files,
 };

This page was automatically generated by the 2.1.0 LXR engine. The LXR team