Re: [PATCH] mm/memcg: use exist interface to get css from memcg

From: Bob Liu
Date: Wed Jul 18 2012 - 05:23:29 EST


On Wed, Jul 18, 2012 at 5:06 PM, Wanpeng Li <liwanp@xxxxxxxxxxxxxxxxxx> wrote:
> Signed-off-by: Wanpeng Li <liwanp@xxxxxxxxxxxxxxxxxx>
>
> ---
> mm/memcontrol.c | 82 ++++++++++++++++++++++++++++---------------------------
> 1 files changed, 42 insertions(+), 40 deletions(-)
>
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index 20f6a15..42788b0 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -467,7 +467,7 @@ mem_cgroup_zoneinfo(struct mem_cgroup *memcg, int nid, int zid)
>
> struct cgroup_subsys_state *mem_cgroup_css(struct mem_cgroup *memcg)
> {
> - return &memcg->css;
> + return mem_cgroup_css(memcg);
> }

??

>
> static struct mem_cgroup_per_zone *
> @@ -861,7 +861,7 @@ struct mem_cgroup *try_get_mem_cgroup_from_mm(struct mm_struct *mm)
> memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
> if (unlikely(!memcg))
> break;
> - } while (!css_tryget(&memcg->css));
> + } while (!css_tryget(mem_cgroup_css(memcg)));
> rcu_read_unlock();
> return memcg;
> }
> @@ -897,10 +897,10 @@ struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *root,
> root = root_mem_cgroup;
>
> if (prev && !reclaim)
> - id = css_id(&prev->css);
> + id = css_id(mem_cgroup_css(prev));
>
> if (prev && prev != root)
> - css_put(&prev->css);
> + css_put(mem_cgroup_css(prev));
>
> if (!root->use_hierarchy && root != root_mem_cgroup) {
> if (prev)
> @@ -925,9 +925,10 @@ struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *root,
> }
>
> rcu_read_lock();
> - css = css_get_next(&mem_cgroup_subsys, id + 1, &root->css, &id);
> + css = css_get_next(&mem_cgroup_subsys,
> + id + 1, mem_cgroup_css(root), &id);
> if (css) {
> - if (css == &root->css || css_tryget(css))
> + if (css == mem_cgroup_css(root) || css_tryget(css))
> memcg = mem_cgroup_from_css(css,
> struct mem_cgroup, css);
> } else
> @@ -959,7 +960,7 @@ void mem_cgroup_iter_break(struct mem_cgroup *root,
> if (!root)
> root = root_mem_cgroup;
> if (prev && prev != root)
> - css_put(&prev->css);
> + css_put(mem_cgroup_css(prev));
> }
>
> /*
> @@ -1153,7 +1154,8 @@ static bool mem_cgroup_same_or_subtree(const struct mem_cgroup *root_memcg,
> {
> if (root_memcg != memcg) {
> return (root_memcg->use_hierarchy &&
> - css_is_ancestor(&memcg->css, &root_memcg->css));
> + css_is_ancestor(mem_cgroup_css(memcg),
> + mem_cgroup_css(root_memcg)));
> }
>
> return true;
> @@ -1178,7 +1180,7 @@ int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *memcg)
> task_lock(task);
> curr = mem_cgroup_from_task(task);
> if (curr)
> - css_get(&curr->css);
> + css_get(mem_cgroup_css(curr));
> task_unlock(task);
> }
> if (!curr)
> @@ -1190,7 +1192,7 @@ int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *memcg)
> * hierarchy(even if use_hierarchy is disabled in "memcg").
> */
> ret = mem_cgroup_same_or_subtree(memcg, curr);
> - css_put(&curr->css);
> + css_put(mem_cgroup_css(curr));
> return ret;
> }
>
> @@ -1282,7 +1284,7 @@ static unsigned long mem_cgroup_margin(struct mem_cgroup *memcg)
>
> int mem_cgroup_swappiness(struct mem_cgroup *memcg)
> {
> - struct cgroup *cgrp = memcg->css.cgroup;
> + struct cgroup *cgrp = mem_cgroup_css(memcg)->cgroup;
>
> /* root ? */
> if (cgrp->parent == NULL)
> @@ -1402,7 +1404,7 @@ void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p)
>
> rcu_read_lock();
>
> - mem_cgrp = memcg->css.cgroup;
> + mem_cgrp = mem_cgroup_css(memcg)->cgroup;
> task_cgrp = task_cgroup(p, mem_cgroup_subsys_id);
>
> ret = cgroup_path(task_cgrp, memcg_name, PATH_MAX);
> @@ -2276,12 +2278,12 @@ static int __mem_cgroup_try_charge(struct mm_struct *mm,
> again:
> if (*ptr) { /* css should be a valid one */
> memcg = *ptr;
> - VM_BUG_ON(css_is_removed(&memcg->css));
> + VM_BUG_ON(css_is_removed(mem_cgroup_css(memcg)));
> if (mem_cgroup_is_root(memcg))
> goto done;
> if (nr_pages == 1 && consume_stock(memcg))
> goto done;
> - css_get(&memcg->css);
> + css_get(mem_cgroup_css(memcg));
> } else {
> struct task_struct *p;
>
> @@ -2317,7 +2319,7 @@ again:
> goto done;
> }
> /* after here, we may be blocked. we need to get refcnt */
> - if (!css_tryget(&memcg->css)) {
> + if (!css_tryget(mem_cgroup_css(memcg))) {
> rcu_read_unlock();
> goto again;
> }
> @@ -2329,7 +2331,7 @@ again:
>
> /* If killed, bypass charge */
> if (fatal_signal_pending(current)) {
> - css_put(&memcg->css);
> + css_put(mem_cgroup_css(memcg));
> goto bypass;
> }
>
> @@ -2345,29 +2347,29 @@ again:
> break;
> case CHARGE_RETRY: /* not in OOM situation but retry */
> batch = nr_pages;
> - css_put(&memcg->css);
> + css_put(mem_cgroup_css(memcg));
> memcg = NULL;
> goto again;
> case CHARGE_WOULDBLOCK: /* !__GFP_WAIT */
> - css_put(&memcg->css);
> + css_put(mem_cgroup_css(memcg));
> goto nomem;
> case CHARGE_NOMEM: /* OOM routine works */
> if (!oom) {
> - css_put(&memcg->css);
> + css_put(mem_cgroup_css(memcg));
> goto nomem;
> }
> /* If oom, we never return -ENOMEM */
> nr_oom_retries--;
> break;
> case CHARGE_OOM_DIE: /* Killed by OOM Killer */
> - css_put(&memcg->css);
> + css_put(mem_cgroup_css(memcg));
> goto bypass;
> }
> } while (ret != CHARGE_OK);
>
> if (batch > nr_pages)
> refill_stock(memcg, batch - nr_pages);
> - css_put(&memcg->css);
> + css_put(mem_cgroup_css(memcg));
> done:
> *ptr = memcg;
> return 0;
> @@ -2428,14 +2430,14 @@ struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page)
> lock_page_cgroup(pc);
> if (PageCgroupUsed(pc)) {
> memcg = pc->mem_cgroup;
> - if (memcg && !css_tryget(&memcg->css))
> + if (memcg && !css_tryget(mem_cgroup_css(memcg)))
> memcg = NULL;
> } else if (PageSwapCache(page)) {
> ent.val = page_private(page);
> id = lookup_swap_cgroup_id(ent);
> rcu_read_lock();
> memcg = mem_cgroup_lookup(id);
> - if (memcg && !css_tryget(&memcg->css))
> + if (memcg && !css_tryget(mem_cgroup_css(memcg)))
> memcg = NULL;
> rcu_read_unlock();
> }
> @@ -2640,7 +2642,7 @@ static int mem_cgroup_move_parent(struct page *page,
> struct mem_cgroup *child,
> gfp_t gfp_mask)
> {
> - struct cgroup *cg = child->css.cgroup;
> + struct cgroup *cg = mem_cgroup_css(child)->cgroup;
> struct cgroup *pcg = cg->parent;
> struct mem_cgroup *parent;
> unsigned int nr_pages;
> @@ -2790,7 +2792,7 @@ int mem_cgroup_try_charge_swapin(struct mm_struct *mm,
> goto charge_cur_mm;
> *memcgp = memcg;
> ret = __mem_cgroup_try_charge(NULL, mask, 1, memcgp, true);
> - css_put(&memcg->css);
> + css_put(mem_cgroup_css(memcg));
> if (ret == -EINTR)
> ret = 0;
> return ret;
> @@ -2813,7 +2815,7 @@ __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *memcg,
> return;
> if (!memcg)
> return;
> - cgroup_exclude_rmdir(&memcg->css);
> + cgroup_exclude_rmdir(mem_cgroup_css(memcg));
>
> pc = lookup_page_cgroup(page);
> __mem_cgroup_commit_charge(memcg, page, 1, pc, ctype, true);
> @@ -2850,7 +2852,7 @@ __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *memcg,
> * So, rmdir()->pre_destroy() can be called while we do this charge.
> * In that case, we need to call pre_destroy() again. check it here.
> */
> - cgroup_release_and_wakeup_rmdir(&memcg->css);
> + cgroup_release_and_wakeup_rmdir(mem_cgroup_css(memcg));
> }
>
> void mem_cgroup_commit_charge_swapin(struct page *page,
> @@ -3089,7 +3091,7 @@ mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent, bool swapout)
> * mem_cgroup_get() was called in uncharge().
> */
> if (do_swap_account && swapout && memcg)
> - swap_cgroup_record(ent, css_id(&memcg->css));
> + swap_cgroup_record(ent, css_id(mem_cgroup_css(memcg)));
> }
> #endif
>
> @@ -3142,8 +3144,8 @@ static int mem_cgroup_move_swap_account(swp_entry_t entry,
> {
> unsigned short old_id, new_id;
>
> - old_id = css_id(&from->css);
> - new_id = css_id(&to->css);
> + old_id = css_id(mem_cgroup_css(from));
> + new_id = css_id(mem_cgroup_css(to));
>
> if (swap_cgroup_cmpxchg(entry, old_id, new_id) == old_id) {
> mem_cgroup_swap_statistics(from, false);
> @@ -3202,7 +3204,7 @@ int mem_cgroup_prepare_migration(struct page *page,
> lock_page_cgroup(pc);
> if (PageCgroupUsed(pc)) {
> memcg = pc->mem_cgroup;
> - css_get(&memcg->css);
> + css_get(mem_cgroup_css(memcg));
> /*
> * At migrating an anonymous page, its mapcount goes down
> * to 0 and uncharge() will be called. But, even if it's fully
> @@ -3245,7 +3247,7 @@ int mem_cgroup_prepare_migration(struct page *page,
>
> *memcgp = memcg;
> ret = __mem_cgroup_try_charge(NULL, gfp_mask, 1, memcgp, false);
> - css_put(&memcg->css);/* drop extra refcnt */
> + css_put(mem_cgroup_css(memcg));/* drop extra refcnt */
> if (ret) {
> if (PageAnon(page)) {
> lock_page_cgroup(pc);
> @@ -3286,7 +3288,7 @@ void mem_cgroup_end_migration(struct mem_cgroup *memcg,
> if (!memcg)
> return;
> /* blocks rmdir() */
> - cgroup_exclude_rmdir(&memcg->css);
> + cgroup_exclude_rmdir(mem_cgroup_css(memcg));
> if (!migration_ok) {
> used = oldpage;
> unused = newpage;
> @@ -3322,7 +3324,7 @@ void mem_cgroup_end_migration(struct mem_cgroup *memcg,
> * So, rmdir()->pre_destroy() can be called while we do this charge.
> * In that case, we need to call pre_destroy() again. check it here.
> */
> - cgroup_release_and_wakeup_rmdir(&memcg->css);
> + cgroup_release_and_wakeup_rmdir(mem_cgroup_css(memcg));
> }
>
> /*
> @@ -3686,9 +3688,9 @@ static int mem_cgroup_force_empty(struct mem_cgroup *memcg, bool free_all)
> int ret;
> int node, zid, shrink;
> int nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
> - struct cgroup *cgrp = memcg->css.cgroup;
> + struct cgroup *cgrp = mem_cgroup_css(memcg)->cgroup;
>
> - css_get(&memcg->css);
> + css_get(mem_cgroup_css(memcg));
>
> shrink = 0;
> /* should free all ? */
> @@ -3729,7 +3731,7 @@ move_account:
> /* "ret" should also be checked to ensure all lists are empty. */
> } while (memcg->res.usage > 0 || ret);
> out:
> - css_put(&memcg->css);
> + css_put(mem_cgroup_css(memcg));
> return ret;
>
> try_to_free:
> @@ -3928,7 +3930,7 @@ static void memcg_get_hierarchical_limit(struct mem_cgroup *memcg,
>
> min_limit = res_counter_read_u64(&memcg->res, RES_LIMIT);
> min_memsw_limit = res_counter_read_u64(&memcg->memsw, RES_LIMIT);
> - cgroup = memcg->css.cgroup;
> + cgroup = mem_cgroup_css(memcg)->cgroup;
> if (!memcg->use_hierarchy)
> goto out;
>
> @@ -4842,7 +4844,7 @@ static void __mem_cgroup_free(struct mem_cgroup *memcg)
> int node;
>
> mem_cgroup_remove_from_trees(memcg);
> - free_css_id(&mem_cgroup_subsys, &memcg->css);
> + free_css_id(&mem_cgroup_subsys, mem_cgroup_css(memcg));
>
> for_each_node(node)
> free_mem_cgroup_per_zone_info(memcg, node);
> @@ -4989,7 +4991,7 @@ mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont)
> atomic_set(&memcg->refcnt, 1);
> memcg->move_charge_at_immigrate = 0;
> mutex_init(&memcg->thresholds_lock);
> - return &memcg->css;
> + return mem_cgroup_css(memcg);
> free_out:
> __mem_cgroup_free(memcg);
> return ERR_PTR(error);
> --
> 1.7.5.4
>
> --
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--
Regards,
--Bob
--
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