From 79bd9814e5ec9a288d6599f53aeac0b548fdfe52 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 22 Nov 2013 18:20:42 -0500 Subject: cgroup, memcg: move cgroup_event implementation to memcg cgroup_event is way over-designed and tries to build a generic flexible event mechanism into cgroup - fully customizable event specification for each user of the interface. This is utterly unnecessary and overboard especially in the light of the planned unified hierarchy as there's gonna be single agent. Simply generating events at fixed points, or if that's too restrictive, configureable cadence or single set of configureable points should be enough. Thankfully, memcg is the only user and gets to keep it. Replacing it with something simpler on sane_behavior is strongly recommended. This patch moves cgroup_event and "cgroup.event_control" implementation to mm/memcontrol.c. Clearing of events on cgroup destruction is moved from cgroup_destroy_locked() to mem_cgroup_css_offline(), which shouldn't make any noticeable difference. cgroup_css() and __file_cft() are exported to enable the move; however, this will soon be reverted once the event code is updated to be memcg specific. Note that "cgroup.event_control" will now exist only on the hierarchy with memcg attached to it. While this change is visible to userland, it is unlikely to be noticeable as the file has never been meaningful outside memcg. Aside from the above change, this is pure code relocation. v2: Per Li Zefan's comments, init/Kconfig updated accordingly and poll.h inclusion moved from cgroup.c to memcontrol.c. Signed-off-by: Tejun Heo Acked-by: Li Zefan Acked-by: Kirill A. Shutemov Acked-by: Michal Hocko Cc: Johannes Weiner Cc: Balbir Singh --- mm/memcontrol.c | 248 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 248 insertions(+) (limited to 'mm') diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 13b9d0f221b..02dae329266 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -45,6 +45,7 @@ #include #include #include +#include #include #include #include @@ -55,6 +56,7 @@ #include #include #include +#include #include "internal.h" #include #include @@ -226,6 +228,36 @@ struct mem_cgroup_eventfd_list { struct eventfd_ctx *eventfd; }; +/* + * cgroup_event represents events which userspace want to receive. + */ +struct cgroup_event { + /* + * css which the event belongs to. + */ + struct cgroup_subsys_state *css; + /* + * Control file which the event associated. + */ + struct cftype *cft; + /* + * eventfd to signal userspace about the event. + */ + struct eventfd_ctx *eventfd; + /* + * Each of these stored in a list by the cgroup. + */ + struct list_head list; + /* + * All fields below needed to unregister event when + * userspace closes eventfd. + */ + poll_table pt; + wait_queue_head_t *wqh; + wait_queue_t wait; + struct work_struct remove; +}; + static void mem_cgroup_threshold(struct mem_cgroup *memcg); static void mem_cgroup_oom_notify(struct mem_cgroup *memcg); @@ -5947,6 +5979,202 @@ static void kmem_cgroup_css_offline(struct mem_cgroup *memcg) } #endif +/* + * Unregister event and free resources. + * + * Gets called from workqueue. + */ +static void cgroup_event_remove(struct work_struct *work) +{ + struct cgroup_event *event = container_of(work, struct cgroup_event, + remove); + struct cgroup_subsys_state *css = event->css; + + remove_wait_queue(event->wqh, &event->wait); + + event->cft->unregister_event(css, event->cft, event->eventfd); + + /* Notify userspace the event is going away. */ + eventfd_signal(event->eventfd, 1); + + eventfd_ctx_put(event->eventfd); + kfree(event); + css_put(css); +} + +/* + * Gets called on POLLHUP on eventfd when user closes it. + * + * Called with wqh->lock held and interrupts disabled. + */ +static int cgroup_event_wake(wait_queue_t *wait, unsigned mode, + int sync, void *key) +{ + struct cgroup_event *event = container_of(wait, + struct cgroup_event, wait); + struct cgroup *cgrp = event->css->cgroup; + unsigned long flags = (unsigned long)key; + + if (flags & POLLHUP) { + /* + * If the event has been detached at cgroup removal, we + * can simply return knowing the other side will cleanup + * for us. + * + * We can't race against event freeing since the other + * side will require wqh->lock via remove_wait_queue(), + * which we hold. + */ + spin_lock(&cgrp->event_list_lock); + if (!list_empty(&event->list)) { + list_del_init(&event->list); + /* + * We are in atomic context, but cgroup_event_remove() + * may sleep, so we have to call it in workqueue. + */ + schedule_work(&event->remove); + } + spin_unlock(&cgrp->event_list_lock); + } + + return 0; +} + +static void cgroup_event_ptable_queue_proc(struct file *file, + wait_queue_head_t *wqh, poll_table *pt) +{ + struct cgroup_event *event = container_of(pt, + struct cgroup_event, pt); + + event->wqh = wqh; + add_wait_queue(wqh, &event->wait); +} + +/* + * Parse input and register new cgroup event handler. + * + * Input must be in format ' '. + * Interpretation of args is defined by control file implementation. + */ +static int cgroup_write_event_control(struct cgroup_subsys_state *dummy_css, + struct cftype *cft, const char *buffer) +{ + struct cgroup *cgrp = dummy_css->cgroup; + struct cgroup_event *event; + struct cgroup_subsys_state *cfile_css; + unsigned int efd, cfd; + struct fd efile; + struct fd cfile; + char *endp; + int ret; + + efd = simple_strtoul(buffer, &endp, 10); + if (*endp != ' ') + return -EINVAL; + buffer = endp + 1; + + cfd = simple_strtoul(buffer, &endp, 10); + if ((*endp != ' ') && (*endp != '\0')) + return -EINVAL; + buffer = endp + 1; + + event = kzalloc(sizeof(*event), GFP_KERNEL); + if (!event) + return -ENOMEM; + + INIT_LIST_HEAD(&event->list); + init_poll_funcptr(&event->pt, cgroup_event_ptable_queue_proc); + init_waitqueue_func_entry(&event->wait, cgroup_event_wake); + INIT_WORK(&event->remove, cgroup_event_remove); + + efile = fdget(efd); + if (!efile.file) { + ret = -EBADF; + goto out_kfree; + } + + event->eventfd = eventfd_ctx_fileget(efile.file); + if (IS_ERR(event->eventfd)) { + ret = PTR_ERR(event->eventfd); + goto out_put_efile; + } + + cfile = fdget(cfd); + if (!cfile.file) { + ret = -EBADF; + goto out_put_eventfd; + } + + /* the process need read permission on control file */ + /* AV: shouldn't we check that it's been opened for read instead? */ + ret = inode_permission(file_inode(cfile.file), MAY_READ); + if (ret < 0) + goto out_put_cfile; + + event->cft = __file_cft(cfile.file); + if (IS_ERR(event->cft)) { + ret = PTR_ERR(event->cft); + goto out_put_cfile; + } + + if (!event->cft->ss) { + ret = -EBADF; + goto out_put_cfile; + } + + /* + * Determine the css of @cfile, verify it belongs to the same + * cgroup as cgroup.event_control, and associate @event with it. + * Remaining events are automatically removed on cgroup destruction + * but the removal is asynchronous, so take an extra ref. + */ + rcu_read_lock(); + + ret = -EINVAL; + event->css = cgroup_css(cgrp, event->cft->ss); + cfile_css = css_from_dir(cfile.file->f_dentry->d_parent, event->cft->ss); + if (event->css && event->css == cfile_css && css_tryget(event->css)) + ret = 0; + + rcu_read_unlock(); + if (ret) + goto out_put_cfile; + + if (!event->cft->register_event || !event->cft->unregister_event) { + ret = -EINVAL; + goto out_put_css; + } + + ret = event->cft->register_event(event->css, event->cft, + event->eventfd, buffer); + if (ret) + goto out_put_css; + + efile.file->f_op->poll(efile.file, &event->pt); + + spin_lock(&cgrp->event_list_lock); + list_add(&event->list, &cgrp->event_list); + spin_unlock(&cgrp->event_list_lock); + + fdput(cfile); + fdput(efile); + + return 0; + +out_put_css: + css_put(event->css); +out_put_cfile: + fdput(cfile); +out_put_eventfd: + eventfd_ctx_put(event->eventfd); +out_put_efile: + fdput(efile); +out_kfree: + kfree(event); + + return ret; +} + static struct cftype mem_cgroup_files[] = { { .name = "usage_in_bytes", @@ -5993,6 +6221,12 @@ static struct cftype mem_cgroup_files[] = { .write_u64 = mem_cgroup_hierarchy_write, .read_u64 = mem_cgroup_hierarchy_read, }, + { + .name = "cgroup.event_control", + .write_string = cgroup_write_event_control, + .flags = CFTYPE_NO_PREFIX, + .mode = S_IWUGO, + }, { .name = "swappiness", .read_u64 = mem_cgroup_swappiness_read, @@ -6326,6 +6560,20 @@ static void mem_cgroup_invalidate_reclaim_iterators(struct mem_cgroup *memcg) static void mem_cgroup_css_offline(struct cgroup_subsys_state *css) { struct mem_cgroup *memcg = mem_cgroup_from_css(css); + struct cgroup *cgrp = css->cgroup; + struct cgroup_event *event, *tmp; + + /* + * Unregister events and notify userspace. + * Notify userspace about cgroup removing only after rmdir of cgroup + * directory to avoid race between userspace and kernelspace. + */ + spin_lock(&cgrp->event_list_lock); + list_for_each_entry_safe(event, tmp, &cgrp->event_list, list) { + list_del_init(&event->list); + schedule_work(&event->remove); + } + spin_unlock(&cgrp->event_list_lock); kmem_cgroup_css_offline(memcg); -- cgit v1.2.3-70-g09d2 From b5557c4c3b1a38074d7001b87c2482eda3a0834a Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 22 Nov 2013 18:20:42 -0500 Subject: memcg: cgroup_write_event_control() now knows @css is for memcg @css for cgroup_write_event_control() is now always for memcg and the target file should be a memcg file too. Drop code which assumes @css is dummy_css and the target file may belong to different subsystems. Signed-off-by: Tejun Heo Acked-by: Li Zefan Acked-by: Kirill A. Shutemov --- mm/memcontrol.c | 27 +++++++++++---------------- 1 file changed, 11 insertions(+), 16 deletions(-) (limited to 'mm') diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 02dae329266..d00368110b0 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -6056,10 +6056,10 @@ static void cgroup_event_ptable_queue_proc(struct file *file, * Input must be in format ' '. * Interpretation of args is defined by control file implementation. */ -static int cgroup_write_event_control(struct cgroup_subsys_state *dummy_css, +static int cgroup_write_event_control(struct cgroup_subsys_state *css, struct cftype *cft, const char *buffer) { - struct cgroup *cgrp = dummy_css->cgroup; + struct cgroup *cgrp = css->cgroup; struct cgroup_event *event; struct cgroup_subsys_state *cfile_css; unsigned int efd, cfd; @@ -6082,6 +6082,7 @@ static int cgroup_write_event_control(struct cgroup_subsys_state *dummy_css, if (!event) return -ENOMEM; + event->css = css; INIT_LIST_HEAD(&event->list); init_poll_funcptr(&event->pt, cgroup_event_ptable_queue_proc); init_waitqueue_func_entry(&event->wait, cgroup_event_wake); @@ -6117,23 +6118,17 @@ static int cgroup_write_event_control(struct cgroup_subsys_state *dummy_css, goto out_put_cfile; } - if (!event->cft->ss) { - ret = -EBADF; - goto out_put_cfile; - } - /* - * Determine the css of @cfile, verify it belongs to the same - * cgroup as cgroup.event_control, and associate @event with it. - * Remaining events are automatically removed on cgroup destruction - * but the removal is asynchronous, so take an extra ref. + * Verify @cfile should belong to @css. Also, remaining events are + * automatically removed on cgroup destruction but the removal is + * asynchronous, so take an extra ref on @css. */ rcu_read_lock(); ret = -EINVAL; - event->css = cgroup_css(cgrp, event->cft->ss); - cfile_css = css_from_dir(cfile.file->f_dentry->d_parent, event->cft->ss); - if (event->css && event->css == cfile_css && css_tryget(event->css)) + cfile_css = css_from_dir(cfile.file->f_dentry->d_parent, + &mem_cgroup_subsys); + if (cfile_css == css && css_tryget(css)) ret = 0; rcu_read_unlock(); @@ -6145,7 +6140,7 @@ static int cgroup_write_event_control(struct cgroup_subsys_state *dummy_css, goto out_put_css; } - ret = event->cft->register_event(event->css, event->cft, + ret = event->cft->register_event(css, event->cft, event->eventfd, buffer); if (ret) goto out_put_css; @@ -6162,7 +6157,7 @@ static int cgroup_write_event_control(struct cgroup_subsys_state *dummy_css, return 0; out_put_css: - css_put(event->css); + css_put(css); out_put_cfile: fdput(cfile); out_put_eventfd: -- cgit v1.2.3-70-g09d2 From fba94807837850e211f8975e1970e23e7804ff4d Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 22 Nov 2013 18:20:43 -0500 Subject: cgroup, memcg: move cgroup->event_list[_lock] and event callbacks into memcg cgroup_event is being moved from cgroup core to memcg and the implementation is already moved by the previous patch. This patch moves the data fields and callbacks. * cgroup->event_list[_lock] are moved to mem_cgroup. * cftype->[un]register_event() are moved to cgroup_event. This makes it impossible for individual cftype definitions to specify their event callbacks. This is worked around by simply hard-coding filename to event callback mapping in cgroup_write_event_control(). This is awkward and inflexible, which is actually desirable given that we don't want to grow more usages of this feature. * eventfd_ctx declaration is removed from cgroup.h, which makes vmpressure.h miss eventfd_ctx declaration. Include eventfd.h from vmpressure.h. v2: Use file name from dentry instead of cftype. This will allow removing all cftype handling in the function. Signed-off-by: Tejun Heo Acked-by: Li Zefan Acked-by: Kirill A. Shutemov Acked-by: Michal Hocko Cc: Johannes Weiner Cc: Balbir Singh --- include/linux/cgroup.h | 24 ------------- include/linux/vmpressure.h | 1 + kernel/cgroup.c | 2 -- mm/memcontrol.c | 87 ++++++++++++++++++++++++++++++++-------------- 4 files changed, 61 insertions(+), 53 deletions(-) (limited to 'mm') diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 40c2427806c..612adc5b87c 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -29,7 +29,6 @@ struct cgroup_subsys; struct inode; struct cgroup; struct css_id; -struct eventfd_ctx; extern int cgroup_init_early(void); extern int cgroup_init(void); @@ -239,10 +238,6 @@ struct cgroup { struct rcu_head rcu_head; struct work_struct destroy_work; - /* List of events which userspace want to receive */ - struct list_head event_list; - spinlock_t event_list_lock; - /* directory xattrs */ struct simple_xattrs xattrs; }; @@ -506,25 +501,6 @@ struct cftype { int (*trigger)(struct cgroup_subsys_state *css, unsigned int event); int (*release)(struct inode *inode, struct file *file); - - /* - * register_event() callback will be used to add new userspace - * waiter for changes related to the cftype. Implement it if - * you want to provide this functionality. Use eventfd_signal() - * on eventfd to send notification to userspace. - */ - int (*register_event)(struct cgroup_subsys_state *css, - struct cftype *cft, struct eventfd_ctx *eventfd, - const char *args); - /* - * unregister_event() callback will be called when userspace - * closes the eventfd or on cgroup removing. - * This callback must be implemented, if you want provide - * notification functionality. - */ - void (*unregister_event)(struct cgroup_subsys_state *css, - struct cftype *cft, - struct eventfd_ctx *eventfd); }; /* diff --git a/include/linux/vmpressure.h b/include/linux/vmpressure.h index 3f3788d4936..9dd1914f1a6 100644 --- a/include/linux/vmpressure.h +++ b/include/linux/vmpressure.h @@ -7,6 +7,7 @@ #include #include #include +#include struct vmpressure { unsigned long scanned; diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 4bccaa7dda3..feda7c54fa6 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -1352,8 +1352,6 @@ static void init_cgroup_housekeeping(struct cgroup *cgrp) INIT_LIST_HEAD(&cgrp->pidlists); mutex_init(&cgrp->pidlist_mutex); cgrp->dummy_css.cgroup = cgrp; - INIT_LIST_HEAD(&cgrp->event_list); - spin_lock_init(&cgrp->event_list_lock); simple_xattrs_init(&cgrp->xattrs); } diff --git a/mm/memcontrol.c b/mm/memcontrol.c index d00368110b0..2fcacb18404 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -248,6 +248,22 @@ struct cgroup_event { * Each of these stored in a list by the cgroup. */ struct list_head list; + /* + * register_event() callback will be used to add new userspace + * waiter for changes related to this event. Use eventfd_signal() + * on eventfd to send notification to userspace. + */ + int (*register_event)(struct cgroup_subsys_state *css, + struct cftype *cft, struct eventfd_ctx *eventfd, + const char *args); + /* + * unregister_event() callback will be called when userspace closes + * the eventfd or on cgroup removing. This callback must be set, + * if you want provide notification functionality. + */ + void (*unregister_event)(struct cgroup_subsys_state *css, + struct cftype *cft, + struct eventfd_ctx *eventfd); /* * All fields below needed to unregister event when * userspace closes eventfd. @@ -362,6 +378,10 @@ struct mem_cgroup { atomic_t numainfo_updating; #endif + /* List of events which userspace want to receive */ + struct list_head event_list; + spinlock_t event_list_lock; + struct mem_cgroup_per_node *nodeinfo[0]; /* WARNING: nodeinfo must be the last member here */ }; @@ -5992,7 +6012,7 @@ static void cgroup_event_remove(struct work_struct *work) remove_wait_queue(event->wqh, &event->wait); - event->cft->unregister_event(css, event->cft, event->eventfd); + event->unregister_event(css, event->cft, event->eventfd); /* Notify userspace the event is going away. */ eventfd_signal(event->eventfd, 1); @@ -6012,7 +6032,7 @@ static int cgroup_event_wake(wait_queue_t *wait, unsigned mode, { struct cgroup_event *event = container_of(wait, struct cgroup_event, wait); - struct cgroup *cgrp = event->css->cgroup; + struct mem_cgroup *memcg = mem_cgroup_from_css(event->css); unsigned long flags = (unsigned long)key; if (flags & POLLHUP) { @@ -6025,7 +6045,7 @@ static int cgroup_event_wake(wait_queue_t *wait, unsigned mode, * side will require wqh->lock via remove_wait_queue(), * which we hold. */ - spin_lock(&cgrp->event_list_lock); + spin_lock(&memcg->event_list_lock); if (!list_empty(&event->list)) { list_del_init(&event->list); /* @@ -6034,7 +6054,7 @@ static int cgroup_event_wake(wait_queue_t *wait, unsigned mode, */ schedule_work(&event->remove); } - spin_unlock(&cgrp->event_list_lock); + spin_unlock(&memcg->event_list_lock); } return 0; @@ -6059,12 +6079,13 @@ static void cgroup_event_ptable_queue_proc(struct file *file, static int cgroup_write_event_control(struct cgroup_subsys_state *css, struct cftype *cft, const char *buffer) { - struct cgroup *cgrp = css->cgroup; + struct mem_cgroup *memcg = mem_cgroup_from_css(css); struct cgroup_event *event; struct cgroup_subsys_state *cfile_css; unsigned int efd, cfd; struct fd efile; struct fd cfile; + const char *name; char *endp; int ret; @@ -6118,6 +6139,31 @@ static int cgroup_write_event_control(struct cgroup_subsys_state *css, goto out_put_cfile; } + /* + * Determine the event callbacks and set them in @event. This used + * to be done via struct cftype but cgroup core no longer knows + * about these events. The following is crude but the whole thing + * is for compatibility anyway. + */ + name = cfile.file->f_dentry->d_name.name; + + if (!strcmp(name, "memory.usage_in_bytes")) { + event->register_event = mem_cgroup_usage_register_event; + event->unregister_event = mem_cgroup_usage_unregister_event; + } else if (!strcmp(name, "memory.oom_control")) { + event->register_event = mem_cgroup_oom_register_event; + event->unregister_event = mem_cgroup_oom_unregister_event; + } else if (!strcmp(name, "memory.pressure_level")) { + event->register_event = vmpressure_register_event; + event->unregister_event = vmpressure_unregister_event; + } else if (!strcmp(name, "memory.memsw.usage_in_bytes")) { + event->register_event = mem_cgroup_usage_register_event; + event->unregister_event = mem_cgroup_usage_unregister_event; + } else { + ret = -EINVAL; + goto out_put_cfile; + } + /* * Verify @cfile should belong to @css. Also, remaining events are * automatically removed on cgroup destruction but the removal is @@ -6135,21 +6181,15 @@ static int cgroup_write_event_control(struct cgroup_subsys_state *css, if (ret) goto out_put_cfile; - if (!event->cft->register_event || !event->cft->unregister_event) { - ret = -EINVAL; - goto out_put_css; - } - - ret = event->cft->register_event(css, event->cft, - event->eventfd, buffer); + ret = event->register_event(css, event->cft, event->eventfd, buffer); if (ret) goto out_put_css; efile.file->f_op->poll(efile.file, &event->pt); - spin_lock(&cgrp->event_list_lock); - list_add(&event->list, &cgrp->event_list); - spin_unlock(&cgrp->event_list_lock); + spin_lock(&memcg->event_list_lock); + list_add(&event->list, &memcg->event_list); + spin_unlock(&memcg->event_list_lock); fdput(cfile); fdput(efile); @@ -6175,8 +6215,6 @@ static struct cftype mem_cgroup_files[] = { .name = "usage_in_bytes", .private = MEMFILE_PRIVATE(_MEM, RES_USAGE), .read = mem_cgroup_read, - .register_event = mem_cgroup_usage_register_event, - .unregister_event = mem_cgroup_usage_unregister_event, }, { .name = "max_usage_in_bytes", @@ -6236,14 +6274,10 @@ static struct cftype mem_cgroup_files[] = { .name = "oom_control", .read_map = mem_cgroup_oom_control_read, .write_u64 = mem_cgroup_oom_control_write, - .register_event = mem_cgroup_oom_register_event, - .unregister_event = mem_cgroup_oom_unregister_event, .private = MEMFILE_PRIVATE(_OOM_TYPE, OOM_CONTROL), }, { .name = "pressure_level", - .register_event = vmpressure_register_event, - .unregister_event = vmpressure_unregister_event, }, #ifdef CONFIG_NUMA { @@ -6291,8 +6325,6 @@ static struct cftype memsw_cgroup_files[] = { .name = "memsw.usage_in_bytes", .private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE), .read = mem_cgroup_read, - .register_event = mem_cgroup_usage_register_event, - .unregister_event = mem_cgroup_usage_unregister_event, }, { .name = "memsw.max_usage_in_bytes", @@ -6483,6 +6515,8 @@ mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) mutex_init(&memcg->thresholds_lock); spin_lock_init(&memcg->move_lock); vmpressure_init(&memcg->vmpressure); + INIT_LIST_HEAD(&memcg->event_list); + spin_lock_init(&memcg->event_list_lock); return &memcg->css; @@ -6555,7 +6589,6 @@ static void mem_cgroup_invalidate_reclaim_iterators(struct mem_cgroup *memcg) static void mem_cgroup_css_offline(struct cgroup_subsys_state *css) { struct mem_cgroup *memcg = mem_cgroup_from_css(css); - struct cgroup *cgrp = css->cgroup; struct cgroup_event *event, *tmp; /* @@ -6563,12 +6596,12 @@ static void mem_cgroup_css_offline(struct cgroup_subsys_state *css) * Notify userspace about cgroup removing only after rmdir of cgroup * directory to avoid race between userspace and kernelspace. */ - spin_lock(&cgrp->event_list_lock); - list_for_each_entry_safe(event, tmp, &cgrp->event_list, list) { + spin_lock(&memcg->event_list_lock); + list_for_each_entry_safe(event, tmp, &memcg->event_list, list) { list_del_init(&event->list); schedule_work(&event->remove); } - spin_unlock(&cgrp->event_list_lock); + spin_unlock(&memcg->event_list_lock); kmem_cgroup_css_offline(memcg); -- cgit v1.2.3-70-g09d2 From 347c4a8747104a945ecced358944e42879176ca5 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 22 Nov 2013 18:20:43 -0500 Subject: memcg: remove cgroup_event->cft The only use of cgroup_event->cft is distinguishing "usage_in_bytes" and "memsw.usgae_in_bytes" for mem_cgroup_usage_[un]register_event(), which can be done by adding an explicit argument to the function and implementing two wrappers so that the two cases can be distinguished from the function alone. Remove cgroup_event->cft and the related code including [un]register_events() methods. Signed-off-by: Tejun Heo Acked-by: Li Zefan Acked-by: Kirill A. Shutemov Acked-by: Michal Hocko --- include/linux/vmpressure.h | 2 -- mm/memcontrol.c | 65 +++++++++++++++++++++++++--------------------- mm/vmpressure.c | 14 +++------- 3 files changed, 38 insertions(+), 43 deletions(-) (limited to 'mm') diff --git a/include/linux/vmpressure.h b/include/linux/vmpressure.h index 9dd1914f1a6..b048365a7ed 100644 --- a/include/linux/vmpressure.h +++ b/include/linux/vmpressure.h @@ -36,11 +36,9 @@ extern struct vmpressure *memcg_to_vmpressure(struct mem_cgroup *memcg); extern struct cgroup_subsys_state *vmpressure_to_css(struct vmpressure *vmpr); extern struct vmpressure *css_to_vmpressure(struct cgroup_subsys_state *css); extern int vmpressure_register_event(struct cgroup_subsys_state *css, - struct cftype *cft, struct eventfd_ctx *eventfd, const char *args); extern void vmpressure_unregister_event(struct cgroup_subsys_state *css, - struct cftype *cft, struct eventfd_ctx *eventfd); #else static inline void vmpressure(gfp_t gfp, struct mem_cgroup *memcg, diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 2fcacb18404..3c93dcfd26d 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -236,10 +236,6 @@ struct cgroup_event { * css which the event belongs to. */ struct cgroup_subsys_state *css; - /* - * Control file which the event associated. - */ - struct cftype *cft; /* * eventfd to signal userspace about the event. */ @@ -254,15 +250,13 @@ struct cgroup_event { * on eventfd to send notification to userspace. */ int (*register_event)(struct cgroup_subsys_state *css, - struct cftype *cft, struct eventfd_ctx *eventfd, - const char *args); + struct eventfd_ctx *eventfd, const char *args); /* * unregister_event() callback will be called when userspace closes * the eventfd or on cgroup removing. This callback must be set, * if you want provide notification functionality. */ void (*unregister_event)(struct cgroup_subsys_state *css, - struct cftype *cft, struct eventfd_ctx *eventfd); /* * All fields below needed to unregister event when @@ -5688,13 +5682,12 @@ static void mem_cgroup_oom_notify(struct mem_cgroup *memcg) mem_cgroup_oom_notify_cb(iter); } -static int mem_cgroup_usage_register_event(struct cgroup_subsys_state *css, - struct cftype *cft, struct eventfd_ctx *eventfd, const char *args) +static int __mem_cgroup_usage_register_event(struct cgroup_subsys_state *css, + struct eventfd_ctx *eventfd, const char *args, enum res_type type) { struct mem_cgroup *memcg = mem_cgroup_from_css(css); struct mem_cgroup_thresholds *thresholds; struct mem_cgroup_threshold_ary *new; - enum res_type type = MEMFILE_TYPE(cft->private); u64 threshold, usage; int i, size, ret; @@ -5771,13 +5764,24 @@ unlock: return ret; } -static void mem_cgroup_usage_unregister_event(struct cgroup_subsys_state *css, - struct cftype *cft, struct eventfd_ctx *eventfd) +static int mem_cgroup_usage_register_event(struct cgroup_subsys_state *css, + struct eventfd_ctx *eventfd, const char *args) +{ + return __mem_cgroup_usage_register_event(css, eventfd, args, _MEM); +} + +static int memsw_cgroup_usage_register_event(struct cgroup_subsys_state *css, + struct eventfd_ctx *eventfd, const char *args) +{ + return __mem_cgroup_usage_register_event(css, eventfd, args, _MEMSWAP); +} + +static void __mem_cgroup_usage_unregister_event(struct cgroup_subsys_state *css, + struct eventfd_ctx *eventfd, enum res_type type) { struct mem_cgroup *memcg = mem_cgroup_from_css(css); struct mem_cgroup_thresholds *thresholds; struct mem_cgroup_threshold_ary *new; - enum res_type type = MEMFILE_TYPE(cft->private); u64 usage; int i, j, size; @@ -5850,14 +5854,24 @@ unlock: mutex_unlock(&memcg->thresholds_lock); } +static void mem_cgroup_usage_unregister_event(struct cgroup_subsys_state *css, + struct eventfd_ctx *eventfd) +{ + return __mem_cgroup_usage_unregister_event(css, eventfd, _MEM); +} + +static void memsw_cgroup_usage_unregister_event(struct cgroup_subsys_state *css, + struct eventfd_ctx *eventfd) +{ + return __mem_cgroup_usage_unregister_event(css, eventfd, _MEMSWAP); +} + static int mem_cgroup_oom_register_event(struct cgroup_subsys_state *css, - struct cftype *cft, struct eventfd_ctx *eventfd, const char *args) + struct eventfd_ctx *eventfd, const char *args) { struct mem_cgroup *memcg = mem_cgroup_from_css(css); struct mem_cgroup_eventfd_list *event; - enum res_type type = MEMFILE_TYPE(cft->private); - BUG_ON(type != _OOM_TYPE); event = kmalloc(sizeof(*event), GFP_KERNEL); if (!event) return -ENOMEM; @@ -5876,13 +5890,10 @@ static int mem_cgroup_oom_register_event(struct cgroup_subsys_state *css, } static void mem_cgroup_oom_unregister_event(struct cgroup_subsys_state *css, - struct cftype *cft, struct eventfd_ctx *eventfd) + struct eventfd_ctx *eventfd) { struct mem_cgroup *memcg = mem_cgroup_from_css(css); struct mem_cgroup_eventfd_list *ev, *tmp; - enum res_type type = MEMFILE_TYPE(cft->private); - - BUG_ON(type != _OOM_TYPE); spin_lock(&memcg_oom_lock); @@ -6012,7 +6023,7 @@ static void cgroup_event_remove(struct work_struct *work) remove_wait_queue(event->wqh, &event->wait); - event->unregister_event(css, event->cft, event->eventfd); + event->unregister_event(css, event->eventfd); /* Notify userspace the event is going away. */ eventfd_signal(event->eventfd, 1); @@ -6133,12 +6144,6 @@ static int cgroup_write_event_control(struct cgroup_subsys_state *css, if (ret < 0) goto out_put_cfile; - event->cft = __file_cft(cfile.file); - if (IS_ERR(event->cft)) { - ret = PTR_ERR(event->cft); - goto out_put_cfile; - } - /* * Determine the event callbacks and set them in @event. This used * to be done via struct cftype but cgroup core no longer knows @@ -6157,8 +6162,8 @@ static int cgroup_write_event_control(struct cgroup_subsys_state *css, event->register_event = vmpressure_register_event; event->unregister_event = vmpressure_unregister_event; } else if (!strcmp(name, "memory.memsw.usage_in_bytes")) { - event->register_event = mem_cgroup_usage_register_event; - event->unregister_event = mem_cgroup_usage_unregister_event; + event->register_event = memsw_cgroup_usage_register_event; + event->unregister_event = memsw_cgroup_usage_unregister_event; } else { ret = -EINVAL; goto out_put_cfile; @@ -6181,7 +6186,7 @@ static int cgroup_write_event_control(struct cgroup_subsys_state *css, if (ret) goto out_put_cfile; - ret = event->register_event(css, event->cft, event->eventfd, buffer); + ret = event->register_event(css, event->eventfd, buffer); if (ret) goto out_put_css; diff --git a/mm/vmpressure.c b/mm/vmpressure.c index e0f62837c3f..0f25a996d15 100644 --- a/mm/vmpressure.c +++ b/mm/vmpressure.c @@ -279,7 +279,6 @@ void vmpressure_prio(gfp_t gfp, struct mem_cgroup *memcg, int prio) /** * vmpressure_register_event() - Bind vmpressure notifications to an eventfd * @css: css that is interested in vmpressure notifications - * @cft: cgroup control files handle * @eventfd: eventfd context to link notifications with * @args: event arguments (used to set up a pressure level threshold) * @@ -289,13 +288,10 @@ void vmpressure_prio(gfp_t gfp, struct mem_cgroup *memcg, int prio) * threshold (one of vmpressure_str_levels, i.e. "low", "medium", or * "critical"). * - * This function should not be used directly, just pass it to (struct - * cftype).register_event, and then cgroup core will handle everything by - * itself. + * To be used as memcg event method. */ int vmpressure_register_event(struct cgroup_subsys_state *css, - struct cftype *cft, struct eventfd_ctx *eventfd, - const char *args) + struct eventfd_ctx *eventfd, const char *args) { struct vmpressure *vmpr = css_to_vmpressure(css); struct vmpressure_event *ev; @@ -326,19 +322,15 @@ int vmpressure_register_event(struct cgroup_subsys_state *css, /** * vmpressure_unregister_event() - Unbind eventfd from vmpressure * @css: css handle - * @cft: cgroup control files handle * @eventfd: eventfd context that was used to link vmpressure with the @cg * * This function does internal manipulations to detach the @eventfd from * the vmpressure notifications, and then frees internal resources * associated with the @eventfd (but the @eventfd itself is not freed). * - * This function should not be used directly, just pass it to (struct - * cftype).unregister_event, and then cgroup core will handle everything - * by itself. + * To be used as memcg event method. */ void vmpressure_unregister_event(struct cgroup_subsys_state *css, - struct cftype *cft, struct eventfd_ctx *eventfd) { struct vmpressure *vmpr = css_to_vmpressure(css); -- cgit v1.2.3-70-g09d2 From 59b6f87344ab5eb3057e5844b8cd8a39e668f477 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 22 Nov 2013 18:20:43 -0500 Subject: memcg: make cgroup_event deal with mem_cgroup instead of cgroup_subsys_state cgroup_event is now memcg specific. Replace cgroup_event->css with ->memcg and convert [un]register_event() callbacks to take mem_cgroup pointer instead of cgroup_subsys_state one. This simplifies the code slightly and makes css_to_vmpressure() unnecessary which is removed. Signed-off-by: Tejun Heo Acked-by: Li Zefan Acked-by: Kirill A. Shutemov Acked-by: Michal Hocko --- include/linux/vmpressure.h | 5 ++--- mm/memcontrol.c | 53 +++++++++++++++++++--------------------------- mm/vmpressure.c | 12 +++++------ 3 files changed, 30 insertions(+), 40 deletions(-) (limited to 'mm') diff --git a/include/linux/vmpressure.h b/include/linux/vmpressure.h index b048365a7ed..3e4535876d3 100644 --- a/include/linux/vmpressure.h +++ b/include/linux/vmpressure.h @@ -34,11 +34,10 @@ extern void vmpressure_init(struct vmpressure *vmpr); extern void vmpressure_cleanup(struct vmpressure *vmpr); extern struct vmpressure *memcg_to_vmpressure(struct mem_cgroup *memcg); extern struct cgroup_subsys_state *vmpressure_to_css(struct vmpressure *vmpr); -extern struct vmpressure *css_to_vmpressure(struct cgroup_subsys_state *css); -extern int vmpressure_register_event(struct cgroup_subsys_state *css, +extern int vmpressure_register_event(struct mem_cgroup *memcg, struct eventfd_ctx *eventfd, const char *args); -extern void vmpressure_unregister_event(struct cgroup_subsys_state *css, +extern void vmpressure_unregister_event(struct mem_cgroup *memcg, struct eventfd_ctx *eventfd); #else static inline void vmpressure(gfp_t gfp, struct mem_cgroup *memcg, diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 3c93dcfd26d..42f2843af1a 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -233,9 +233,9 @@ struct mem_cgroup_eventfd_list { */ struct cgroup_event { /* - * css which the event belongs to. + * memcg which the event belongs to. */ - struct cgroup_subsys_state *css; + struct mem_cgroup *memcg; /* * eventfd to signal userspace about the event. */ @@ -249,14 +249,14 @@ struct cgroup_event { * waiter for changes related to this event. Use eventfd_signal() * on eventfd to send notification to userspace. */ - int (*register_event)(struct cgroup_subsys_state *css, + int (*register_event)(struct mem_cgroup *memcg, struct eventfd_ctx *eventfd, const char *args); /* * unregister_event() callback will be called when userspace closes * the eventfd or on cgroup removing. This callback must be set, * if you want provide notification functionality. */ - void (*unregister_event)(struct cgroup_subsys_state *css, + void (*unregister_event)(struct mem_cgroup *memcg, struct eventfd_ctx *eventfd); /* * All fields below needed to unregister event when @@ -535,11 +535,6 @@ struct cgroup_subsys_state *vmpressure_to_css(struct vmpressure *vmpr) return &container_of(vmpr, struct mem_cgroup, vmpressure)->css; } -struct vmpressure *css_to_vmpressure(struct cgroup_subsys_state *css) -{ - return &mem_cgroup_from_css(css)->vmpressure; -} - static inline bool mem_cgroup_is_root(struct mem_cgroup *memcg) { return (memcg == root_mem_cgroup); @@ -5682,10 +5677,9 @@ static void mem_cgroup_oom_notify(struct mem_cgroup *memcg) mem_cgroup_oom_notify_cb(iter); } -static int __mem_cgroup_usage_register_event(struct cgroup_subsys_state *css, +static int __mem_cgroup_usage_register_event(struct mem_cgroup *memcg, struct eventfd_ctx *eventfd, const char *args, enum res_type type) { - struct mem_cgroup *memcg = mem_cgroup_from_css(css); struct mem_cgroup_thresholds *thresholds; struct mem_cgroup_threshold_ary *new; u64 threshold, usage; @@ -5764,22 +5758,21 @@ unlock: return ret; } -static int mem_cgroup_usage_register_event(struct cgroup_subsys_state *css, +static int mem_cgroup_usage_register_event(struct mem_cgroup *memcg, struct eventfd_ctx *eventfd, const char *args) { - return __mem_cgroup_usage_register_event(css, eventfd, args, _MEM); + return __mem_cgroup_usage_register_event(memcg, eventfd, args, _MEM); } -static int memsw_cgroup_usage_register_event(struct cgroup_subsys_state *css, +static int memsw_cgroup_usage_register_event(struct mem_cgroup *memcg, struct eventfd_ctx *eventfd, const char *args) { - return __mem_cgroup_usage_register_event(css, eventfd, args, _MEMSWAP); + return __mem_cgroup_usage_register_event(memcg, eventfd, args, _MEMSWAP); } -static void __mem_cgroup_usage_unregister_event(struct cgroup_subsys_state *css, +static void __mem_cgroup_usage_unregister_event(struct mem_cgroup *memcg, struct eventfd_ctx *eventfd, enum res_type type) { - struct mem_cgroup *memcg = mem_cgroup_from_css(css); struct mem_cgroup_thresholds *thresholds; struct mem_cgroup_threshold_ary *new; u64 usage; @@ -5854,22 +5847,21 @@ unlock: mutex_unlock(&memcg->thresholds_lock); } -static void mem_cgroup_usage_unregister_event(struct cgroup_subsys_state *css, +static void mem_cgroup_usage_unregister_event(struct mem_cgroup *memcg, struct eventfd_ctx *eventfd) { - return __mem_cgroup_usage_unregister_event(css, eventfd, _MEM); + return __mem_cgroup_usage_unregister_event(memcg, eventfd, _MEM); } -static void memsw_cgroup_usage_unregister_event(struct cgroup_subsys_state *css, +static void memsw_cgroup_usage_unregister_event(struct mem_cgroup *memcg, struct eventfd_ctx *eventfd) { - return __mem_cgroup_usage_unregister_event(css, eventfd, _MEMSWAP); + return __mem_cgroup_usage_unregister_event(memcg, eventfd, _MEMSWAP); } -static int mem_cgroup_oom_register_event(struct cgroup_subsys_state *css, +static int mem_cgroup_oom_register_event(struct mem_cgroup *memcg, struct eventfd_ctx *eventfd, const char *args) { - struct mem_cgroup *memcg = mem_cgroup_from_css(css); struct mem_cgroup_eventfd_list *event; event = kmalloc(sizeof(*event), GFP_KERNEL); @@ -5889,10 +5881,9 @@ static int mem_cgroup_oom_register_event(struct cgroup_subsys_state *css, return 0; } -static void mem_cgroup_oom_unregister_event(struct cgroup_subsys_state *css, +static void mem_cgroup_oom_unregister_event(struct mem_cgroup *memcg, struct eventfd_ctx *eventfd) { - struct mem_cgroup *memcg = mem_cgroup_from_css(css); struct mem_cgroup_eventfd_list *ev, *tmp; spin_lock(&memcg_oom_lock); @@ -6019,18 +6010,18 @@ static void cgroup_event_remove(struct work_struct *work) { struct cgroup_event *event = container_of(work, struct cgroup_event, remove); - struct cgroup_subsys_state *css = event->css; + struct mem_cgroup *memcg = event->memcg; remove_wait_queue(event->wqh, &event->wait); - event->unregister_event(css, event->eventfd); + event->unregister_event(memcg, event->eventfd); /* Notify userspace the event is going away. */ eventfd_signal(event->eventfd, 1); eventfd_ctx_put(event->eventfd); kfree(event); - css_put(css); + css_put(&memcg->css); } /* @@ -6043,7 +6034,7 @@ static int cgroup_event_wake(wait_queue_t *wait, unsigned mode, { struct cgroup_event *event = container_of(wait, struct cgroup_event, wait); - struct mem_cgroup *memcg = mem_cgroup_from_css(event->css); + struct mem_cgroup *memcg = event->memcg; unsigned long flags = (unsigned long)key; if (flags & POLLHUP) { @@ -6114,7 +6105,7 @@ static int cgroup_write_event_control(struct cgroup_subsys_state *css, if (!event) return -ENOMEM; - event->css = css; + event->memcg = memcg; INIT_LIST_HEAD(&event->list); init_poll_funcptr(&event->pt, cgroup_event_ptable_queue_proc); init_waitqueue_func_entry(&event->wait, cgroup_event_wake); @@ -6186,7 +6177,7 @@ static int cgroup_write_event_control(struct cgroup_subsys_state *css, if (ret) goto out_put_cfile; - ret = event->register_event(css, event->eventfd, buffer); + ret = event->register_event(memcg, event->eventfd, buffer); if (ret) goto out_put_css; diff --git a/mm/vmpressure.c b/mm/vmpressure.c index 0f25a996d15..196970a4541 100644 --- a/mm/vmpressure.c +++ b/mm/vmpressure.c @@ -278,7 +278,7 @@ void vmpressure_prio(gfp_t gfp, struct mem_cgroup *memcg, int prio) /** * vmpressure_register_event() - Bind vmpressure notifications to an eventfd - * @css: css that is interested in vmpressure notifications + * @memcg: memcg that is interested in vmpressure notifications * @eventfd: eventfd context to link notifications with * @args: event arguments (used to set up a pressure level threshold) * @@ -290,10 +290,10 @@ void vmpressure_prio(gfp_t gfp, struct mem_cgroup *memcg, int prio) * * To be used as memcg event method. */ -int vmpressure_register_event(struct cgroup_subsys_state *css, +int vmpressure_register_event(struct mem_cgroup *memcg, struct eventfd_ctx *eventfd, const char *args) { - struct vmpressure *vmpr = css_to_vmpressure(css); + struct vmpressure *vmpr = memcg_to_vmpressure(memcg); struct vmpressure_event *ev; int level; @@ -321,7 +321,7 @@ int vmpressure_register_event(struct cgroup_subsys_state *css, /** * vmpressure_unregister_event() - Unbind eventfd from vmpressure - * @css: css handle + * @memcg: memcg handle * @eventfd: eventfd context that was used to link vmpressure with the @cg * * This function does internal manipulations to detach the @eventfd from @@ -330,10 +330,10 @@ int vmpressure_register_event(struct cgroup_subsys_state *css, * * To be used as memcg event method. */ -void vmpressure_unregister_event(struct cgroup_subsys_state *css, +void vmpressure_unregister_event(struct mem_cgroup *memcg, struct eventfd_ctx *eventfd) { - struct vmpressure *vmpr = css_to_vmpressure(css); + struct vmpressure *vmpr = memcg_to_vmpressure(memcg); struct vmpressure_event *ev; mutex_lock(&vmpr->events_lock); -- cgit v1.2.3-70-g09d2 From 3bc942f372af383f49d56aab599469561a5e39ec Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 22 Nov 2013 18:20:44 -0500 Subject: memcg: rename cgroup_event to mem_cgroup_event cgroup_event is only available in memcg now. Let's brand it that way. While at it, add a comment encouraging deprecation of the feature and remove the respective section from cgroup documentation. This patch is cosmetic. v3: Typo update as per Li Zefan. v2: Index in cgroups.txt updated accordingly as suggested by Li Zefan. Signed-off-by: Tejun Heo Acked-by: Li Zefan Acked-by: Kirill A. Shutemov Acked-by: Michal Hocko --- Documentation/cgroups/cgroups.txt | 20 -------------- mm/memcontrol.c | 57 +++++++++++++++++++++++++-------------- 2 files changed, 37 insertions(+), 40 deletions(-) (limited to 'mm') diff --git a/Documentation/cgroups/cgroups.txt b/Documentation/cgroups/cgroups.txt index 638bf17ff86..821de56d158 100644 --- a/Documentation/cgroups/cgroups.txt +++ b/Documentation/cgroups/cgroups.txt @@ -24,7 +24,6 @@ CONTENTS: 2.1 Basic Usage 2.2 Attaching processes 2.3 Mounting hierarchies by name - 2.4 Notification API 3. Kernel API 3.1 Overview 3.2 Synchronization @@ -472,25 +471,6 @@ you give a subsystem a name. The name of the subsystem appears as part of the hierarchy description in /proc/mounts and /proc//cgroups. -2.4 Notification API --------------------- - -There is mechanism which allows to get notifications about changing -status of a cgroup. - -To register a new notification handler you need to: - - create a file descriptor for event notification using eventfd(2); - - open a control file to be monitored (e.g. memory.usage_in_bytes); - - write " " to cgroup.event_control. - Interpretation of args is defined by control file implementation; - -eventfd will be woken up by control file implementation or when the -cgroup is removed. - -To unregister a notification handler just close eventfd. - -NOTE: Support of notifications should be implemented for the control -file. See documentation for the subsystem. 3. Kernel API ============= diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 42f2843af1a..ec8582b3a23 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -231,7 +231,7 @@ struct mem_cgroup_eventfd_list { /* * cgroup_event represents events which userspace want to receive. */ -struct cgroup_event { +struct mem_cgroup_event { /* * memcg which the event belongs to. */ @@ -6001,15 +6001,28 @@ static void kmem_cgroup_css_offline(struct mem_cgroup *memcg) } #endif +/* + * DO NOT USE IN NEW FILES. + * + * "cgroup.event_control" implementation. + * + * This is way over-engineered. It tries to support fully configurable + * events for each user. Such level of flexibility is completely + * unnecessary especially in the light of the planned unified hierarchy. + * + * Please deprecate this and replace with something simpler if at all + * possible. + */ + /* * Unregister event and free resources. * * Gets called from workqueue. */ -static void cgroup_event_remove(struct work_struct *work) +static void memcg_event_remove(struct work_struct *work) { - struct cgroup_event *event = container_of(work, struct cgroup_event, - remove); + struct mem_cgroup_event *event = + container_of(work, struct mem_cgroup_event, remove); struct mem_cgroup *memcg = event->memcg; remove_wait_queue(event->wqh, &event->wait); @@ -6029,11 +6042,11 @@ static void cgroup_event_remove(struct work_struct *work) * * Called with wqh->lock held and interrupts disabled. */ -static int cgroup_event_wake(wait_queue_t *wait, unsigned mode, - int sync, void *key) +static int memcg_event_wake(wait_queue_t *wait, unsigned mode, + int sync, void *key) { - struct cgroup_event *event = container_of(wait, - struct cgroup_event, wait); + struct mem_cgroup_event *event = + container_of(wait, struct mem_cgroup_event, wait); struct mem_cgroup *memcg = event->memcg; unsigned long flags = (unsigned long)key; @@ -6062,27 +6075,29 @@ static int cgroup_event_wake(wait_queue_t *wait, unsigned mode, return 0; } -static void cgroup_event_ptable_queue_proc(struct file *file, +static void memcg_event_ptable_queue_proc(struct file *file, wait_queue_head_t *wqh, poll_table *pt) { - struct cgroup_event *event = container_of(pt, - struct cgroup_event, pt); + struct mem_cgroup_event *event = + container_of(pt, struct mem_cgroup_event, pt); event->wqh = wqh; add_wait_queue(wqh, &event->wait); } /* + * DO NOT USE IN NEW FILES. + * * Parse input and register new cgroup event handler. * * Input must be in format ' '. * Interpretation of args is defined by control file implementation. */ -static int cgroup_write_event_control(struct cgroup_subsys_state *css, - struct cftype *cft, const char *buffer) +static int memcg_write_event_control(struct cgroup_subsys_state *css, + struct cftype *cft, const char *buffer) { struct mem_cgroup *memcg = mem_cgroup_from_css(css); - struct cgroup_event *event; + struct mem_cgroup_event *event; struct cgroup_subsys_state *cfile_css; unsigned int efd, cfd; struct fd efile; @@ -6107,9 +6122,9 @@ static int cgroup_write_event_control(struct cgroup_subsys_state *css, event->memcg = memcg; INIT_LIST_HEAD(&event->list); - init_poll_funcptr(&event->pt, cgroup_event_ptable_queue_proc); - init_waitqueue_func_entry(&event->wait, cgroup_event_wake); - INIT_WORK(&event->remove, cgroup_event_remove); + init_poll_funcptr(&event->pt, memcg_event_ptable_queue_proc); + init_waitqueue_func_entry(&event->wait, memcg_event_wake); + INIT_WORK(&event->remove, memcg_event_remove); efile = fdget(efd); if (!efile.file) { @@ -6140,6 +6155,8 @@ static int cgroup_write_event_control(struct cgroup_subsys_state *css, * to be done via struct cftype but cgroup core no longer knows * about these events. The following is crude but the whole thing * is for compatibility anyway. + * + * DO NOT ADD NEW FILES. */ name = cfile.file->f_dentry->d_name.name; @@ -6251,8 +6268,8 @@ static struct cftype mem_cgroup_files[] = { .read_u64 = mem_cgroup_hierarchy_read, }, { - .name = "cgroup.event_control", - .write_string = cgroup_write_event_control, + .name = "cgroup.event_control", /* XXX: for compat */ + .write_string = memcg_write_event_control, .flags = CFTYPE_NO_PREFIX, .mode = S_IWUGO, }, @@ -6585,7 +6602,7 @@ static void mem_cgroup_invalidate_reclaim_iterators(struct mem_cgroup *memcg) static void mem_cgroup_css_offline(struct cgroup_subsys_state *css) { struct mem_cgroup *memcg = mem_cgroup_from_css(css); - struct cgroup_event *event, *tmp; + struct mem_cgroup_event *event, *tmp; /* * Unregister events and notify userspace. -- cgit v1.2.3-70-g09d2 From 791badbdb3e4fc1001ee3bcdaedc6d4f167fcbe8 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 5 Dec 2013 12:28:02 -0500 Subject: memcg: convert away from cftype->read() and ->read_map() In preparation of conversion to kernfs, cgroup file handling is being consolidated so that it can be easily mapped to the seq_file based interface of kernfs. cftype->read_map() doesn't add any value and being replaced with ->read_seq_string(), and all users of cftype->read() can be easily served, usually better, by seq_file and other methods. Update mem_cgroup_read() to return u64 instead of printing itself and rename it to mem_cgroup_read_u64(), and update mem_cgroup_oom_control_read() to use ->read_seq_string() instead of ->read_map(). This patch doesn't make any visible behavior changes. Signed-off-by: Tejun Heo Acked-by: Michal Hocko Acked-by: Li Zefan Cc: Johannes Weiner Cc: Balbir Singh Cc: KAMEZAWA Hiroyuki --- mm/memcontrol.c | 49 +++++++++++++++++++++---------------------------- 1 file changed, 21 insertions(+), 28 deletions(-) (limited to 'mm') diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 7aa0d405b14..f149521a77e 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -5150,14 +5150,12 @@ static inline u64 mem_cgroup_usage(struct mem_cgroup *memcg, bool swap) return val << PAGE_SHIFT; } -static ssize_t mem_cgroup_read(struct cgroup_subsys_state *css, - struct cftype *cft, struct file *file, - char __user *buf, size_t nbytes, loff_t *ppos) +static u64 mem_cgroup_read_u64(struct cgroup_subsys_state *css, + struct cftype *cft) { struct mem_cgroup *memcg = mem_cgroup_from_css(css); - char str[64]; u64 val; - int name, len; + int name; enum res_type type; type = MEMFILE_TYPE(cft->private); @@ -5183,8 +5181,7 @@ static ssize_t mem_cgroup_read(struct cgroup_subsys_state *css, BUG(); } - len = scnprintf(str, sizeof(str), "%llu\n", (unsigned long long)val); - return simple_read_from_buffer(buf, nbytes, ppos, str, len); + return val; } static int memcg_update_kmem_limit(struct cgroup_subsys_state *css, u64 val) @@ -5911,16 +5908,12 @@ static void mem_cgroup_oom_unregister_event(struct mem_cgroup *memcg, } static int mem_cgroup_oom_control_read(struct cgroup_subsys_state *css, - struct cftype *cft, struct cgroup_map_cb *cb) + struct cftype *cft, struct seq_file *sf) { struct mem_cgroup *memcg = mem_cgroup_from_css(css); - cb->fill(cb, "oom_kill_disable", memcg->oom_kill_disable); - - if (atomic_read(&memcg->under_oom)) - cb->fill(cb, "under_oom", 1); - else - cb->fill(cb, "under_oom", 0); + seq_printf(sf, "oom_kill_disable %d\n", memcg->oom_kill_disable); + seq_printf(sf, "under_oom %d\n", (bool)atomic_read(&memcg->under_oom)); return 0; } @@ -6239,31 +6232,31 @@ static struct cftype mem_cgroup_files[] = { { .name = "usage_in_bytes", .private = MEMFILE_PRIVATE(_MEM, RES_USAGE), - .read = mem_cgroup_read, + .read_u64 = mem_cgroup_read_u64, }, { .name = "max_usage_in_bytes", .private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE), .trigger = mem_cgroup_reset, - .read = mem_cgroup_read, + .read_u64 = mem_cgroup_read_u64, }, { .name = "limit_in_bytes", .private = MEMFILE_PRIVATE(_MEM, RES_LIMIT), .write_string = mem_cgroup_write, - .read = mem_cgroup_read, + .read_u64 = mem_cgroup_read_u64, }, { .name = "soft_limit_in_bytes", .private = MEMFILE_PRIVATE(_MEM, RES_SOFT_LIMIT), .write_string = mem_cgroup_write, - .read = mem_cgroup_read, + .read_u64 = mem_cgroup_read_u64, }, { .name = "failcnt", .private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT), .trigger = mem_cgroup_reset, - .read = mem_cgroup_read, + .read_u64 = mem_cgroup_read_u64, }, { .name = "stat", @@ -6297,7 +6290,7 @@ static struct cftype mem_cgroup_files[] = { }, { .name = "oom_control", - .read_map = mem_cgroup_oom_control_read, + .read_seq_string = mem_cgroup_oom_control_read, .write_u64 = mem_cgroup_oom_control_write, .private = MEMFILE_PRIVATE(_OOM_TYPE, OOM_CONTROL), }, @@ -6315,24 +6308,24 @@ static struct cftype mem_cgroup_files[] = { .name = "kmem.limit_in_bytes", .private = MEMFILE_PRIVATE(_KMEM, RES_LIMIT), .write_string = mem_cgroup_write, - .read = mem_cgroup_read, + .read_u64 = mem_cgroup_read_u64, }, { .name = "kmem.usage_in_bytes", .private = MEMFILE_PRIVATE(_KMEM, RES_USAGE), - .read = mem_cgroup_read, + .read_u64 = mem_cgroup_read_u64, }, { .name = "kmem.failcnt", .private = MEMFILE_PRIVATE(_KMEM, RES_FAILCNT), .trigger = mem_cgroup_reset, - .read = mem_cgroup_read, + .read_u64 = mem_cgroup_read_u64, }, { .name = "kmem.max_usage_in_bytes", .private = MEMFILE_PRIVATE(_KMEM, RES_MAX_USAGE), .trigger = mem_cgroup_reset, - .read = mem_cgroup_read, + .read_u64 = mem_cgroup_read_u64, }, #ifdef CONFIG_SLABINFO { @@ -6349,25 +6342,25 @@ static struct cftype memsw_cgroup_files[] = { { .name = "memsw.usage_in_bytes", .private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE), - .read = mem_cgroup_read, + .read_u64 = mem_cgroup_read_u64, }, { .name = "memsw.max_usage_in_bytes", .private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE), .trigger = mem_cgroup_reset, - .read = mem_cgroup_read, + .read_u64 = mem_cgroup_read_u64, }, { .name = "memsw.limit_in_bytes", .private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT), .write_string = mem_cgroup_write, - .read = mem_cgroup_read, + .read_u64 = mem_cgroup_read_u64, }, { .name = "memsw.failcnt", .private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT), .trigger = mem_cgroup_reset, - .read = mem_cgroup_read, + .read_u64 = mem_cgroup_read_u64, }, { }, /* terminate */ }; -- cgit v1.2.3-70-g09d2 From 716f479d279fb456f58be44180d7479da75e5a4e Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 5 Dec 2013 12:28:03 -0500 Subject: hugetlb_cgroup: convert away from cftype->read() In preparation of conversion to kernfs, cgroup file handling is being consolidated so that it can be easily mapped to the seq_file based interface of kernfs. All users of cftype->read() can be easily served, usually better, by seq_file and other methods. Update hugetlb_cgroup_read() to return u64 instead of printing itself and rename it to hugetlb_cgroup_read_u64(). This patch doesn't make any visible behavior changes. Signed-off-by: Tejun Heo Reviewed-by: Michal Hocko Acked-by: Li Zefan Cc: Aneesh Kumar K.V Cc: Johannes Weiner --- mm/hugetlb_cgroup.c | 22 ++++++++-------------- 1 file changed, 8 insertions(+), 14 deletions(-) (limited to 'mm') diff --git a/mm/hugetlb_cgroup.c b/mm/hugetlb_cgroup.c index bda8e44f6fd..d747a84e09b 100644 --- a/mm/hugetlb_cgroup.c +++ b/mm/hugetlb_cgroup.c @@ -242,22 +242,16 @@ void hugetlb_cgroup_uncharge_cgroup(int idx, unsigned long nr_pages, return; } -static ssize_t hugetlb_cgroup_read(struct cgroup_subsys_state *css, - struct cftype *cft, struct file *file, - char __user *buf, size_t nbytes, - loff_t *ppos) +static u64 hugetlb_cgroup_read_u64(struct cgroup_subsys_state *css, + struct cftype *cft) { - u64 val; - char str[64]; - int idx, name, len; + int idx, name; struct hugetlb_cgroup *h_cg = hugetlb_cgroup_from_css(css); idx = MEMFILE_IDX(cft->private); name = MEMFILE_ATTR(cft->private); - val = res_counter_read_u64(&h_cg->hugepage[idx], name); - len = scnprintf(str, sizeof(str), "%llu\n", (unsigned long long)val); - return simple_read_from_buffer(buf, nbytes, ppos, str, len); + return res_counter_read_u64(&h_cg->hugepage[idx], name); } static int hugetlb_cgroup_write(struct cgroup_subsys_state *css, @@ -337,28 +331,28 @@ static void __init __hugetlb_cgroup_file_init(int idx) cft = &h->cgroup_files[0]; snprintf(cft->name, MAX_CFTYPE_NAME, "%s.limit_in_bytes", buf); cft->private = MEMFILE_PRIVATE(idx, RES_LIMIT); - cft->read = hugetlb_cgroup_read; + cft->read_u64 = hugetlb_cgroup_read_u64; cft->write_string = hugetlb_cgroup_write; /* Add the usage file */ cft = &h->cgroup_files[1]; snprintf(cft->name, MAX_CFTYPE_NAME, "%s.usage_in_bytes", buf); cft->private = MEMFILE_PRIVATE(idx, RES_USAGE); - cft->read = hugetlb_cgroup_read; + cft->read_u64 = hugetlb_cgroup_read_u64; /* Add the MAX usage file */ cft = &h->cgroup_files[2]; snprintf(cft->name, MAX_CFTYPE_NAME, "%s.max_usage_in_bytes", buf); cft->private = MEMFILE_PRIVATE(idx, RES_MAX_USAGE); cft->trigger = hugetlb_cgroup_reset; - cft->read = hugetlb_cgroup_read; + cft->read_u64 = hugetlb_cgroup_read_u64; /* Add the failcntfile */ cft = &h->cgroup_files[3]; snprintf(cft->name, MAX_CFTYPE_NAME, "%s.failcnt", buf); cft->private = MEMFILE_PRIVATE(idx, RES_FAILCNT); cft->trigger = hugetlb_cgroup_reset; - cft->read = hugetlb_cgroup_read; + cft->read_u64 = hugetlb_cgroup_read_u64; /* NULL terminate the last cft */ cft = &h->cgroup_files[4]; -- cgit v1.2.3-70-g09d2 From 2da8ca822d49c8b8781800ad155aaa00e7bb5f1a Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 5 Dec 2013 12:28:04 -0500 Subject: cgroup: replace cftype->read_seq_string() with cftype->seq_show() In preparation of conversion to kernfs, cgroup file handling is updated so that it can be easily mapped to kernfs. This patch replaces cftype->read_seq_string() with cftype->seq_show() which is not limited to single_open() operation and will map directcly to kernfs seq_file interface. The conversions are mechanical. As ->seq_show() doesn't have @css and @cft, the functions which make use of them are converted to use seq_css() and seq_cft() respectively. In several occassions, e.f. if it has seq_string in its name, the function name is updated to fit the new method better. This patch does not introduce any behavior changes. Signed-off-by: Tejun Heo Acked-by: Aristeu Rozanski Acked-by: Vivek Goyal Acked-by: Michal Hocko Acked-by: Daniel Wagner Acked-by: Li Zefan Cc: Jens Axboe Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Johannes Weiner Cc: Balbir Singh Cc: KAMEZAWA Hiroyuki Cc: Neil Horman --- block/blk-throttle.c | 35 ++++++------- block/cfq-iosched.c | 131 ++++++++++++++++++++-------------------------- include/linux/cgroup.h | 9 ++-- kernel/cgroup.c | 34 ++++++------ kernel/cgroup_freezer.c | 7 ++- kernel/cpuset.c | 12 ++--- kernel/sched/core.c | 7 ++- kernel/sched/cpuacct.c | 14 +++-- mm/memcontrol.c | 28 +++++----- net/core/netprio_cgroup.c | 8 +-- security/device_cgroup.c | 7 ++- 11 files changed, 128 insertions(+), 164 deletions(-) (limited to 'mm') diff --git a/block/blk-throttle.c b/block/blk-throttle.c index 06534049afb..a760857e6b6 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -1303,13 +1303,10 @@ static u64 tg_prfill_cpu_rwstat(struct seq_file *sf, return __blkg_prfill_rwstat(sf, pd, &rwstat); } -static int tg_print_cpu_rwstat(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *sf) +static int tg_print_cpu_rwstat(struct seq_file *sf, void *v) { - struct blkcg *blkcg = css_to_blkcg(css); - - blkcg_print_blkgs(sf, blkcg, tg_prfill_cpu_rwstat, &blkcg_policy_throtl, - cft->private, true); + blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), tg_prfill_cpu_rwstat, + &blkcg_policy_throtl, seq_cft(sf)->private, true); return 0; } @@ -1335,19 +1332,17 @@ static u64 tg_prfill_conf_uint(struct seq_file *sf, struct blkg_policy_data *pd, return __blkg_prfill_u64(sf, pd, v); } -static int tg_print_conf_u64(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *sf) +static int tg_print_conf_u64(struct seq_file *sf, void *v) { - blkcg_print_blkgs(sf, css_to_blkcg(css), tg_prfill_conf_u64, - &blkcg_policy_throtl, cft->private, false); + blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), tg_prfill_conf_u64, + &blkcg_policy_throtl, seq_cft(sf)->private, false); return 0; } -static int tg_print_conf_uint(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *sf) +static int tg_print_conf_uint(struct seq_file *sf, void *v) { - blkcg_print_blkgs(sf, css_to_blkcg(css), tg_prfill_conf_uint, - &blkcg_policy_throtl, cft->private, false); + blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), tg_prfill_conf_uint, + &blkcg_policy_throtl, seq_cft(sf)->private, false); return 0; } @@ -1428,40 +1423,40 @@ static struct cftype throtl_files[] = { { .name = "throttle.read_bps_device", .private = offsetof(struct throtl_grp, bps[READ]), - .read_seq_string = tg_print_conf_u64, + .seq_show = tg_print_conf_u64, .write_string = tg_set_conf_u64, .max_write_len = 256, }, { .name = "throttle.write_bps_device", .private = offsetof(struct throtl_grp, bps[WRITE]), - .read_seq_string = tg_print_conf_u64, + .seq_show = tg_print_conf_u64, .write_string = tg_set_conf_u64, .max_write_len = 256, }, { .name = "throttle.read_iops_device", .private = offsetof(struct throtl_grp, iops[READ]), - .read_seq_string = tg_print_conf_uint, + .seq_show = tg_print_conf_uint, .write_string = tg_set_conf_uint, .max_write_len = 256, }, { .name = "throttle.write_iops_device", .private = offsetof(struct throtl_grp, iops[WRITE]), - .read_seq_string = tg_print_conf_uint, + .seq_show = tg_print_conf_uint, .write_string = tg_set_conf_uint, .max_write_len = 256, }, { .name = "throttle.io_service_bytes", .private = offsetof(struct tg_stats_cpu, service_bytes), - .read_seq_string = tg_print_cpu_rwstat, + .seq_show = tg_print_cpu_rwstat, }, { .name = "throttle.io_serviced", .private = offsetof(struct tg_stats_cpu, serviced), - .read_seq_string = tg_print_cpu_rwstat, + .seq_show = tg_print_cpu_rwstat, }, { } /* terminate */ }; diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 4d5cec1ad80..744833b630c 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -1632,11 +1632,11 @@ static u64 cfqg_prfill_weight_device(struct seq_file *sf, return __blkg_prfill_u64(sf, pd, cfqg->dev_weight); } -static int cfqg_print_weight_device(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *sf) +static int cfqg_print_weight_device(struct seq_file *sf, void *v) { - blkcg_print_blkgs(sf, css_to_blkcg(css), cfqg_prfill_weight_device, - &blkcg_policy_cfq, 0, false); + blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), + cfqg_prfill_weight_device, &blkcg_policy_cfq, + 0, false); return 0; } @@ -1650,26 +1650,23 @@ static u64 cfqg_prfill_leaf_weight_device(struct seq_file *sf, return __blkg_prfill_u64(sf, pd, cfqg->dev_leaf_weight); } -static int cfqg_print_leaf_weight_device(struct cgroup_subsys_state *css, - struct cftype *cft, - struct seq_file *sf) +static int cfqg_print_leaf_weight_device(struct seq_file *sf, void *v) { - blkcg_print_blkgs(sf, css_to_blkcg(css), cfqg_prfill_leaf_weight_device, - &blkcg_policy_cfq, 0, false); + blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), + cfqg_prfill_leaf_weight_device, &blkcg_policy_cfq, + 0, false); return 0; } -static int cfq_print_weight(struct cgroup_subsys_state *css, struct cftype *cft, - struct seq_file *sf) +static int cfq_print_weight(struct seq_file *sf, void *v) { - seq_printf(sf, "%u\n", css_to_blkcg(css)->cfq_weight); + seq_printf(sf, "%u\n", css_to_blkcg(seq_css(sf))->cfq_weight); return 0; } -static int cfq_print_leaf_weight(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *sf) +static int cfq_print_leaf_weight(struct seq_file *sf, void *v) { - seq_printf(sf, "%u\n", css_to_blkcg(css)->cfq_leaf_weight); + seq_printf(sf, "%u\n", css_to_blkcg(seq_css(sf))->cfq_leaf_weight); return 0; } @@ -1762,23 +1759,17 @@ static int cfq_set_leaf_weight(struct cgroup_subsys_state *css, return __cfq_set_weight(css, cft, val, true); } -static int cfqg_print_stat(struct cgroup_subsys_state *css, struct cftype *cft, - struct seq_file *sf) +static int cfqg_print_stat(struct seq_file *sf, void *v) { - struct blkcg *blkcg = css_to_blkcg(css); - - blkcg_print_blkgs(sf, blkcg, blkg_prfill_stat, &blkcg_policy_cfq, - cft->private, false); + blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), blkg_prfill_stat, + &blkcg_policy_cfq, seq_cft(sf)->private, false); return 0; } -static int cfqg_print_rwstat(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *sf) +static int cfqg_print_rwstat(struct seq_file *sf, void *v) { - struct blkcg *blkcg = css_to_blkcg(css); - - blkcg_print_blkgs(sf, blkcg, blkg_prfill_rwstat, &blkcg_policy_cfq, - cft->private, true); + blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), blkg_prfill_rwstat, + &blkcg_policy_cfq, seq_cft(sf)->private, true); return 0; } @@ -1798,23 +1789,19 @@ static u64 cfqg_prfill_rwstat_recursive(struct seq_file *sf, return __blkg_prfill_rwstat(sf, pd, &sum); } -static int cfqg_print_stat_recursive(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *sf) +static int cfqg_print_stat_recursive(struct seq_file *sf, void *v) { - struct blkcg *blkcg = css_to_blkcg(css); - - blkcg_print_blkgs(sf, blkcg, cfqg_prfill_stat_recursive, - &blkcg_policy_cfq, cft->private, false); + blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), + cfqg_prfill_stat_recursive, &blkcg_policy_cfq, + seq_cft(sf)->private, false); return 0; } -static int cfqg_print_rwstat_recursive(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *sf) +static int cfqg_print_rwstat_recursive(struct seq_file *sf, void *v) { - struct blkcg *blkcg = css_to_blkcg(css); - - blkcg_print_blkgs(sf, blkcg, cfqg_prfill_rwstat_recursive, - &blkcg_policy_cfq, cft->private, true); + blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), + cfqg_prfill_rwstat_recursive, &blkcg_policy_cfq, + seq_cft(sf)->private, true); return 0; } @@ -1835,13 +1822,11 @@ static u64 cfqg_prfill_avg_queue_size(struct seq_file *sf, } /* print avg_queue_size */ -static int cfqg_print_avg_queue_size(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *sf) +static int cfqg_print_avg_queue_size(struct seq_file *sf, void *v) { - struct blkcg *blkcg = css_to_blkcg(css); - - blkcg_print_blkgs(sf, blkcg, cfqg_prfill_avg_queue_size, - &blkcg_policy_cfq, 0, false); + blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), + cfqg_prfill_avg_queue_size, &blkcg_policy_cfq, + 0, false); return 0; } #endif /* CONFIG_DEBUG_BLK_CGROUP */ @@ -1851,14 +1836,14 @@ static struct cftype cfq_blkcg_files[] = { { .name = "weight_device", .flags = CFTYPE_ONLY_ON_ROOT, - .read_seq_string = cfqg_print_leaf_weight_device, + .seq_show = cfqg_print_leaf_weight_device, .write_string = cfqg_set_leaf_weight_device, .max_write_len = 256, }, { .name = "weight", .flags = CFTYPE_ONLY_ON_ROOT, - .read_seq_string = cfq_print_leaf_weight, + .seq_show = cfq_print_leaf_weight, .write_u64 = cfq_set_leaf_weight, }, @@ -1866,26 +1851,26 @@ static struct cftype cfq_blkcg_files[] = { { .name = "weight_device", .flags = CFTYPE_NOT_ON_ROOT, - .read_seq_string = cfqg_print_weight_device, + .seq_show = cfqg_print_weight_device, .write_string = cfqg_set_weight_device, .max_write_len = 256, }, { .name = "weight", .flags = CFTYPE_NOT_ON_ROOT, - .read_seq_string = cfq_print_weight, + .seq_show = cfq_print_weight, .write_u64 = cfq_set_weight, }, { .name = "leaf_weight_device", - .read_seq_string = cfqg_print_leaf_weight_device, + .seq_show = cfqg_print_leaf_weight_device, .write_string = cfqg_set_leaf_weight_device, .max_write_len = 256, }, { .name = "leaf_weight", - .read_seq_string = cfq_print_leaf_weight, + .seq_show = cfq_print_leaf_weight, .write_u64 = cfq_set_leaf_weight, }, @@ -1893,114 +1878,114 @@ static struct cftype cfq_blkcg_files[] = { { .name = "time", .private = offsetof(struct cfq_group, stats.time), - .read_seq_string = cfqg_print_stat, + .seq_show = cfqg_print_stat, }, { .name = "sectors", .private = offsetof(struct cfq_group, stats.sectors), - .read_seq_string = cfqg_print_stat, + .seq_show = cfqg_print_stat, }, { .name = "io_service_bytes", .private = offsetof(struct cfq_group, stats.service_bytes), - .read_seq_string = cfqg_print_rwstat, + .seq_show = cfqg_print_rwstat, }, { .name = "io_serviced", .private = offsetof(struct cfq_group, stats.serviced), - .read_seq_string = cfqg_print_rwstat, + .seq_show = cfqg_print_rwstat, }, { .name = "io_service_time", .private = offsetof(struct cfq_group, stats.service_time), - .read_seq_string = cfqg_print_rwstat, + .seq_show = cfqg_print_rwstat, }, { .name = "io_wait_time", .private = offsetof(struct cfq_group, stats.wait_time), - .read_seq_string = cfqg_print_rwstat, + .seq_show = cfqg_print_rwstat, }, { .name = "io_merged", .private = offsetof(struct cfq_group, stats.merged), - .read_seq_string = cfqg_print_rwstat, + .seq_show = cfqg_print_rwstat, }, { .name = "io_queued", .private = offsetof(struct cfq_group, stats.queued), - .read_seq_string = cfqg_print_rwstat, + .seq_show = cfqg_print_rwstat, }, /* the same statictics which cover the cfqg and its descendants */ { .name = "time_recursive", .private = offsetof(struct cfq_group, stats.time), - .read_seq_string = cfqg_print_stat_recursive, + .seq_show = cfqg_print_stat_recursive, }, { .name = "sectors_recursive", .private = offsetof(struct cfq_group, stats.sectors), - .read_seq_string = cfqg_print_stat_recursive, + .seq_show = cfqg_print_stat_recursive, }, { .name = "io_service_bytes_recursive", .private = offsetof(struct cfq_group, stats.service_bytes), - .read_seq_string = cfqg_print_rwstat_recursive, + .seq_show = cfqg_print_rwstat_recursive, }, { .name = "io_serviced_recursive", .private = offsetof(struct cfq_group, stats.serviced), - .read_seq_string = cfqg_print_rwstat_recursive, + .seq_show = cfqg_print_rwstat_recursive, }, { .name = "io_service_time_recursive", .private = offsetof(struct cfq_group, stats.service_time), - .read_seq_string = cfqg_print_rwstat_recursive, + .seq_show = cfqg_print_rwstat_recursive, }, { .name = "io_wait_time_recursive", .private = offsetof(struct cfq_group, stats.wait_time), - .read_seq_string = cfqg_print_rwstat_recursive, + .seq_show = cfqg_print_rwstat_recursive, }, { .name = "io_merged_recursive", .private = offsetof(struct cfq_group, stats.merged), - .read_seq_string = cfqg_print_rwstat_recursive, + .seq_show = cfqg_print_rwstat_recursive, }, { .name = "io_queued_recursive", .private = offsetof(struct cfq_group, stats.queued), - .read_seq_string = cfqg_print_rwstat_recursive, + .seq_show = cfqg_print_rwstat_recursive, }, #ifdef CONFIG_DEBUG_BLK_CGROUP { .name = "avg_queue_size", - .read_seq_string = cfqg_print_avg_queue_size, + .seq_show = cfqg_print_avg_queue_size, }, { .name = "group_wait_time", .private = offsetof(struct cfq_group, stats.group_wait_time), - .read_seq_string = cfqg_print_stat, + .seq_show = cfqg_print_stat, }, { .name = "idle_time", .private = offsetof(struct cfq_group, stats.idle_time), - .read_seq_string = cfqg_print_stat, + .seq_show = cfqg_print_stat, }, { .name = "empty_time", .private = offsetof(struct cfq_group, stats.empty_time), - .read_seq_string = cfqg_print_stat, + .seq_show = cfqg_print_stat, }, { .name = "dequeue", .private = offsetof(struct cfq_group, stats.dequeue), - .read_seq_string = cfqg_print_stat, + .seq_show = cfqg_print_stat, }, { .name = "unaccounted_time", .private = offsetof(struct cfq_group, stats.unaccounted_time), - .read_seq_string = cfqg_print_stat, + .seq_show = cfqg_print_stat, }, #endif /* CONFIG_DEBUG_BLK_CGROUP */ { } /* terminate */ diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index c3d698a72e0..b32a0f8ae9a 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -444,12 +444,9 @@ struct cftype { * read_s64() is a signed version of read_u64() */ s64 (*read_s64)(struct cgroup_subsys_state *css, struct cftype *cft); - /* - * read_seq_string() is used for outputting a simple sequence - * using seqfile. - */ - int (*read_seq_string)(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *m); + + /* generic seq_file read interface */ + int (*seq_show)(struct seq_file *sf, void *v); /* * write_u64() is a shortcut for the common case of accepting diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 036c05d8e57..c45e63328a0 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -2212,10 +2212,9 @@ static int cgroup_release_agent_write(struct cgroup_subsys_state *css, return 0; } -static int cgroup_release_agent_show(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *seq) +static int cgroup_release_agent_show(struct seq_file *seq, void *v) { - struct cgroup *cgrp = css->cgroup; + struct cgroup *cgrp = seq_css(seq)->cgroup; if (!cgroup_lock_live_group(cgrp)) return -ENODEV; @@ -2225,10 +2224,11 @@ static int cgroup_release_agent_show(struct cgroup_subsys_state *css, return 0; } -static int cgroup_sane_behavior_show(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *seq) +static int cgroup_sane_behavior_show(struct seq_file *seq, void *v) { - seq_printf(seq, "%d\n", cgroup_sane_behavior(css->cgroup)); + struct cgroup *cgrp = seq_css(seq)->cgroup; + + seq_printf(seq, "%d\n", cgroup_sane_behavior(cgrp)); return 0; } @@ -2291,8 +2291,8 @@ static int cgroup_seqfile_show(struct seq_file *m, void *arg) struct cftype *cft = seq_cft(m); struct cgroup_subsys_state *css = seq_css(m); - if (cft->read_seq_string) - return cft->read_seq_string(css, cft, m); + if (cft->seq_show) + return cft->seq_show(m, arg); if (cft->read_u64) seq_printf(m, "%llu\n", cft->read_u64(css, cft)); @@ -2559,7 +2559,7 @@ static umode_t cgroup_file_mode(const struct cftype *cft) if (cft->mode) return cft->mode; - if (cft->read_u64 || cft->read_s64 || cft->read_seq_string) + if (cft->read_u64 || cft->read_s64 || cft->seq_show) mode |= S_IRUGO; if (cft->write_u64 || cft->write_s64 || cft->write_string || @@ -3874,7 +3874,7 @@ static struct cftype cgroup_base_files[] = { { .name = "cgroup.sane_behavior", .flags = CFTYPE_ONLY_ON_ROOT, - .read_seq_string = cgroup_sane_behavior_show, + .seq_show = cgroup_sane_behavior_show, }, /* @@ -3899,7 +3899,7 @@ static struct cftype cgroup_base_files[] = { { .name = "release_agent", .flags = CFTYPE_INSANE | CFTYPE_ONLY_ON_ROOT, - .read_seq_string = cgroup_release_agent_show, + .seq_show = cgroup_release_agent_show, .write_string = cgroup_release_agent_write, .max_write_len = PATH_MAX, }, @@ -5274,9 +5274,7 @@ static u64 current_css_set_refcount_read(struct cgroup_subsys_state *css, return count; } -static int current_css_set_cg_links_read(struct cgroup_subsys_state *css, - struct cftype *cft, - struct seq_file *seq) +static int current_css_set_cg_links_read(struct seq_file *seq, void *v) { struct cgrp_cset_link *link; struct css_set *cset; @@ -5301,9 +5299,9 @@ static int current_css_set_cg_links_read(struct cgroup_subsys_state *css, } #define MAX_TASKS_SHOWN_PER_CSS 25 -static int cgroup_css_links_read(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *seq) +static int cgroup_css_links_read(struct seq_file *seq, void *v) { + struct cgroup_subsys_state *css = seq_css(seq); struct cgrp_cset_link *link; read_lock(&css_set_lock); @@ -5349,12 +5347,12 @@ static struct cftype debug_files[] = { { .name = "current_css_set_cg_links", - .read_seq_string = current_css_set_cg_links_read, + .seq_show = current_css_set_cg_links_read, }, { .name = "cgroup_css_links", - .read_seq_string = cgroup_css_links_read, + .seq_show = cgroup_css_links_read, }, { diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c index f0ff64d0eba..6c3154e477f 100644 --- a/kernel/cgroup_freezer.c +++ b/kernel/cgroup_freezer.c @@ -301,10 +301,9 @@ out_unlock: spin_unlock_irq(&freezer->lock); } -static int freezer_read(struct cgroup_subsys_state *css, struct cftype *cft, - struct seq_file *m) +static int freezer_read(struct seq_file *m, void *v) { - struct cgroup_subsys_state *pos; + struct cgroup_subsys_state *css = seq_css(m), *pos; rcu_read_lock(); @@ -458,7 +457,7 @@ static struct cftype files[] = { { .name = "state", .flags = CFTYPE_NOT_ON_ROOT, - .read_seq_string = freezer_read, + .seq_show = freezer_read, .write_string = freezer_write, }, { diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 032929f9164..4410ac6a55f 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -1732,12 +1732,10 @@ out_unlock: * and since these maps can change value dynamically, one could read * gibberish by doing partial reads while a list was changing. */ -static int cpuset_common_read_seq_string(struct cgroup_subsys_state *css, - struct cftype *cft, - struct seq_file *sf) +static int cpuset_common_seq_show(struct seq_file *sf, void *v) { - struct cpuset *cs = css_cs(css); - cpuset_filetype_t type = cft->private; + struct cpuset *cs = css_cs(seq_css(sf)); + cpuset_filetype_t type = seq_cft(sf)->private; ssize_t count; char *buf, *s; int ret = 0; @@ -1824,7 +1822,7 @@ static s64 cpuset_read_s64(struct cgroup_subsys_state *css, struct cftype *cft) static struct cftype files[] = { { .name = "cpus", - .read_seq_string = cpuset_common_read_seq_string, + .seq_show = cpuset_common_seq_show, .write_string = cpuset_write_resmask, .max_write_len = (100U + 6 * NR_CPUS), .private = FILE_CPULIST, @@ -1832,7 +1830,7 @@ static struct cftype files[] = { { .name = "mems", - .read_seq_string = cpuset_common_read_seq_string, + .seq_show = cpuset_common_seq_show, .write_string = cpuset_write_resmask, .max_write_len = (100U + 6 * MAX_NUMNODES), .private = FILE_MEMLIST, diff --git a/kernel/sched/core.c b/kernel/sched/core.c index f28ec6722f0..7e8cbb9ee4d 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -7256,10 +7256,9 @@ static int __cfs_schedulable(struct task_group *tg, u64 period, u64 quota) return ret; } -static int cpu_stats_show(struct cgroup_subsys_state *css, struct cftype *cft, - struct seq_file *sf) +static int cpu_stats_show(struct seq_file *sf, void *v) { - struct task_group *tg = css_tg(css); + struct task_group *tg = css_tg(seq_css(sf)); struct cfs_bandwidth *cfs_b = &tg->cfs_bandwidth; seq_printf(sf, "nr_periods %d\n", cfs_b->nr_periods); @@ -7318,7 +7317,7 @@ static struct cftype cpu_files[] = { }, { .name = "stat", - .read_seq_string = cpu_stats_show, + .seq_show = cpu_stats_show, }, #endif #ifdef CONFIG_RT_GROUP_SCHED diff --git a/kernel/sched/cpuacct.c b/kernel/sched/cpuacct.c index dd88738cd4a..622e0818f90 100644 --- a/kernel/sched/cpuacct.c +++ b/kernel/sched/cpuacct.c @@ -163,10 +163,9 @@ out: return err; } -static int cpuacct_percpu_seq_read(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *m) +static int cpuacct_percpu_seq_show(struct seq_file *m, void *V) { - struct cpuacct *ca = css_ca(css); + struct cpuacct *ca = css_ca(seq_css(m)); u64 percpu; int i; @@ -183,10 +182,9 @@ static const char * const cpuacct_stat_desc[] = { [CPUACCT_STAT_SYSTEM] = "system", }; -static int cpuacct_stats_show(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *sf) +static int cpuacct_stats_show(struct seq_file *sf, void *v) { - struct cpuacct *ca = css_ca(css); + struct cpuacct *ca = css_ca(seq_css(sf)); int cpu; s64 val = 0; @@ -220,11 +218,11 @@ static struct cftype files[] = { }, { .name = "usage_percpu", - .read_seq_string = cpuacct_percpu_seq_read, + .seq_show = cpuacct_percpu_seq_show, }, { .name = "stat", - .read_seq_string = cpuacct_stats_show, + .seq_show = cpuacct_stats_show, }, { } /* terminate */ }; diff --git a/mm/memcontrol.c b/mm/memcontrol.c index f149521a77e..9252219376c 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3014,10 +3014,9 @@ static struct kmem_cache *memcg_params_to_cache(struct memcg_cache_params *p) } #ifdef CONFIG_SLABINFO -static int mem_cgroup_slabinfo_read(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *m) +static int mem_cgroup_slabinfo_read(struct seq_file *m, void *v) { - struct mem_cgroup *memcg = mem_cgroup_from_css(css); + struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m)); struct memcg_cache_params *params; if (!memcg_can_account_kmem(memcg)) @@ -5418,8 +5417,7 @@ static int mem_cgroup_move_charge_write(struct cgroup_subsys_state *css, #endif #ifdef CONFIG_NUMA -static int memcg_numa_stat_show(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *m) +static int memcg_numa_stat_show(struct seq_file *m, void *v) { struct numa_stat { const char *name; @@ -5435,7 +5433,7 @@ static int memcg_numa_stat_show(struct cgroup_subsys_state *css, const struct numa_stat *stat; int nid; unsigned long nr; - struct mem_cgroup *memcg = mem_cgroup_from_css(css); + struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m)); for (stat = stats; stat < stats + ARRAY_SIZE(stats); stat++) { nr = mem_cgroup_nr_lru_pages(memcg, stat->lru_mask); @@ -5474,10 +5472,9 @@ static inline void mem_cgroup_lru_names_not_uptodate(void) BUILD_BUG_ON(ARRAY_SIZE(mem_cgroup_lru_names) != NR_LRU_LISTS); } -static int memcg_stat_show(struct cgroup_subsys_state *css, struct cftype *cft, - struct seq_file *m) +static int memcg_stat_show(struct seq_file *m, void *v) { - struct mem_cgroup *memcg = mem_cgroup_from_css(css); + struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m)); struct mem_cgroup *mi; unsigned int i; @@ -5907,10 +5904,9 @@ static void mem_cgroup_oom_unregister_event(struct mem_cgroup *memcg, spin_unlock(&memcg_oom_lock); } -static int mem_cgroup_oom_control_read(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *sf) +static int mem_cgroup_oom_control_read(struct seq_file *sf, void *v) { - struct mem_cgroup *memcg = mem_cgroup_from_css(css); + struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(sf)); seq_printf(sf, "oom_kill_disable %d\n", memcg->oom_kill_disable); seq_printf(sf, "under_oom %d\n", (bool)atomic_read(&memcg->under_oom)); @@ -6260,7 +6256,7 @@ static struct cftype mem_cgroup_files[] = { }, { .name = "stat", - .read_seq_string = memcg_stat_show, + .seq_show = memcg_stat_show, }, { .name = "force_empty", @@ -6290,7 +6286,7 @@ static struct cftype mem_cgroup_files[] = { }, { .name = "oom_control", - .read_seq_string = mem_cgroup_oom_control_read, + .seq_show = mem_cgroup_oom_control_read, .write_u64 = mem_cgroup_oom_control_write, .private = MEMFILE_PRIVATE(_OOM_TYPE, OOM_CONTROL), }, @@ -6300,7 +6296,7 @@ static struct cftype mem_cgroup_files[] = { #ifdef CONFIG_NUMA { .name = "numa_stat", - .read_seq_string = memcg_numa_stat_show, + .seq_show = memcg_numa_stat_show, }, #endif #ifdef CONFIG_MEMCG_KMEM @@ -6330,7 +6326,7 @@ static struct cftype mem_cgroup_files[] = { #ifdef CONFIG_SLABINFO { .name = "kmem.slabinfo", - .read_seq_string = mem_cgroup_slabinfo_read, + .seq_show = mem_cgroup_slabinfo_read, }, #endif #endif diff --git a/net/core/netprio_cgroup.c b/net/core/netprio_cgroup.c index 498710dce4a..56cbb69ba02 100644 --- a/net/core/netprio_cgroup.c +++ b/net/core/netprio_cgroup.c @@ -173,14 +173,14 @@ static u64 read_prioidx(struct cgroup_subsys_state *css, struct cftype *cft) return css->cgroup->id; } -static int read_priomap(struct cgroup_subsys_state *css, struct cftype *cft, - struct seq_file *sf) +static int read_priomap(struct seq_file *sf, void *v) { struct net_device *dev; rcu_read_lock(); for_each_netdev_rcu(&init_net, dev) - seq_printf(sf, "%s %u\n", dev->name, netprio_prio(css, dev)); + seq_printf(sf, "%s %u\n", dev->name, + netprio_prio(seq_css(sf), dev)); rcu_read_unlock(); return 0; } @@ -238,7 +238,7 @@ static struct cftype ss_files[] = { }, { .name = "ifpriomap", - .read_seq_string = read_priomap, + .seq_show = read_priomap, .write_string = write_priomap, }, { } /* terminate */ diff --git a/security/device_cgroup.c b/security/device_cgroup.c index 7c2a0a71049..d3b6d2cd3a0 100644 --- a/security/device_cgroup.c +++ b/security/device_cgroup.c @@ -274,10 +274,9 @@ static void set_majmin(char *str, unsigned m) sprintf(str, "%u", m); } -static int devcgroup_seq_read(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *m) +static int devcgroup_seq_show(struct seq_file *m, void *v) { - struct dev_cgroup *devcgroup = css_to_devcgroup(css); + struct dev_cgroup *devcgroup = css_to_devcgroup(seq_css(m)); struct dev_exception_item *ex; char maj[MAJMINLEN], min[MAJMINLEN], acc[ACCLEN]; @@ -679,7 +678,7 @@ static struct cftype dev_cgroup_files[] = { }, { .name = "list", - .read_seq_string = devcgroup_seq_read, + .seq_show = devcgroup_seq_show, .private = DEVCG_LIST, }, { } /* terminate */ -- cgit v1.2.3-70-g09d2 From b3ff8a2f9569fb41b9cf8902897d787a33bac84f Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Sun, 12 Jan 2014 20:23:27 -0800 Subject: cgroup: remove stray references to css_id Trivial: remove the few stray references to css_id, which itself was removed in v3.13's 2ff2a7d03bbe "cgroup: kill css_id". Signed-off-by: Hugh Dickins Signed-off-by: Tejun Heo --- drivers/md/bcache/request.c | 1 - include/linux/cgroup.h | 3 --- mm/page_cgroup.c | 2 +- 3 files changed, 1 insertion(+), 5 deletions(-) (limited to 'mm') diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c index fbcc851ed5a..61bcfc21d2a 100644 --- a/drivers/md/bcache/request.c +++ b/drivers/md/bcache/request.c @@ -163,7 +163,6 @@ static struct cgroup_subsys_state *bcachecg_create(struct cgroup *cgroup) static void bcachecg_destroy(struct cgroup *cgroup) { struct bch_cgroup *cg = cgroup_to_bcache(cgroup); - free_css_id(&bcache_subsys, &cg->css); kfree(cg); } diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index cfaf416492d..5c097596104 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -29,7 +29,6 @@ struct cgroupfs_root; struct cgroup_subsys; struct inode; struct cgroup; -struct css_id; extern int cgroup_init_early(void); extern int cgroup_init(void); @@ -79,8 +78,6 @@ struct cgroup_subsys_state { struct cgroup_subsys_state *parent; unsigned long flags; - /* ID for this css, if possible */ - struct css_id __rcu *id; /* percpu_ref killing and RCU release */ struct rcu_head rcu_head; diff --git a/mm/page_cgroup.c b/mm/page_cgroup.c index 6d757e3a872..3bd0b8e6ab1 100644 --- a/mm/page_cgroup.c +++ b/mm/page_cgroup.c @@ -451,7 +451,7 @@ unsigned short swap_cgroup_record(swp_entry_t ent, unsigned short id) * lookup_swap_cgroup_id - lookup mem_cgroup id tied to swap entry * @ent: swap entry to be looked up. * - * Returns CSS ID of mem_cgroup at success. 0 at failure. (0 is invalid ID) + * Returns ID of mem_cgroup at success. 0 at failure. (0 is invalid ID) */ unsigned short lookup_swap_cgroup_id(swp_entry_t ent) { -- cgit v1.2.3-70-g09d2