Commit 347c4a87 authored by Tejun Heo's avatar Tejun Heo
Browse files

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: default avatarTejun Heo <tj@kernel.org>
Acked-by: default avatarLi Zefan <lizefan@huawei.com>
Acked-by: default avatarKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: default avatarMichal Hocko <mhocko@suse.cz>
parent fba94807

include/linux/vmpressure.h

+0 −2
Original line number Diff line number Diff line
@@ -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,

mm/memcontrol.c

+35 −30
Original line number Diff line number Diff line
@@ -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;

mm/vmpressure.c

+3 −11
Original line number Diff line number Diff line
@@ -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);

CRA Git | Maintained and supported by SUSTech CRA and CCSE