Re: [RFC][PATCH 2/3] memcg: oom notifier

[KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>]

Thank you.

On Thu, 11 Mar 2010 16:47:00 +0200
"Kirill A. Shutemov" <kirill@shutemov.name> wrote:

> On Thu, Mar 11, 2010 at 9:57 AM, KAMEZAWA Hiroyuki
> <kamezawa.hiroyu@jp.fujitsu.com> wrote:
> > From: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>

> > A  A  A  A /*
> > A  A  A  A  * Should we move charges of a task when a task is moved into this
> > A  A  A  A  * mem_cgroup ? And what type of charges should we move ?
> > @@ -282,9 +292,12 @@ enum charge_type {
> > A /* for encoding cft->private value on file */
> > A #define _MEM A  A  A  A  A  A  A  A  A  (0)
> > A #define _MEMSWAP A  A  A  A  A  A  A  (1)
> > +#define _OOM_TYPE A  A  A  A  A  A  A (2)
> > A #define MEMFILE_PRIVATE(x, val) A  A  A  A (((x) << 16) | (val))
> > A #define MEMFILE_TYPE(val) A  A  A (((val) >> 16) & 0xffff)
> > A #define MEMFILE_ATTR(val) A  A  A ((val) & 0xffff)
> > +/* Used for OOM nofiier */
> > +#define OOM_CONTROL A  A  A  A  A  A (0)
> >
> > A /*
> > A * Reclaim flags for mem_cgroup_hierarchical_reclaim
> > @@ -1351,6 +1364,8 @@ bool mem_cgroup_handle_oom(struct mem_cg
> > A  A  A  A  */
> > A  A  A  A if (!locked)
> > A  A  A  A  A  A  A  A prepare_to_wait(&memcg_oom_waitq, &owait.wait, TASK_KILLABLE);
> > + A  A  A  else
> > + A  A  A  A  A  A  A  mem_cgroup_oom_notify(mem);
> > A  A  A  A mutex_unlock(&memcg_oom_mutex);
> >
> > A  A  A  A if (locked)
> > @@ -3398,8 +3413,22 @@ static int compare_thresholds(const void
> > A  A  A  A return _a->threshold - _b->threshold;
> > A }
> >
> > -static int mem_cgroup_register_event(struct cgroup *cgrp, struct cftype *cft,
> > - A  A  A  A  A  A  A  struct eventfd_ctx *eventfd, const char *args)
> > +static int mem_cgroup_oom_notify_cb(struct mem_cgroup *mem, void *data)
> > +{
> > + A  A  A  struct mem_cgroup_eventfd_list *ev;
> > +
> > + A  A  A  list_for_each_entry(ev, &mem->oom_notify, list)
> > + A  A  A  A  A  A  A  eventfd_signal(ev->eventfd, 1);
> > + A  A  A  return 0;
> > +}
> > +
> > +static void mem_cgroup_oom_notify(struct mem_cgroup *mem)
> > +{
> > + A  A  A  mem_cgroup_walk_tree(mem, NULL, mem_cgroup_oom_notify_cb);
> > +}
> > +
> > +static int mem_cgroup_usage_register_event(struct cgroup *cgrp,
> > + A  A  A  struct cftype *cft, struct eventfd_ctx *eventfd, const char *args)
> > A {
> > A  A  A  A struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp);
> > A  A  A  A struct mem_cgroup_threshold_ary *thresholds, *thresholds_new;
> > @@ -3483,8 +3512,8 @@ unlock:
> > A  A  A  A return ret;
> > A }
> >
> > -static int mem_cgroup_unregister_event(struct cgroup *cgrp, struct cftype *cft,
> > - A  A  A  A  A  A  A  struct eventfd_ctx *eventfd)
> > +static int mem_cgroup_usage_unregister_event(struct cgroup *cgrp,
> > + A  A  A  struct cftype *cft, struct eventfd_ctx *eventfd)
> > A {
> > A  A  A  A struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp);
> > A  A  A  A struct mem_cgroup_threshold_ary *thresholds, *thresholds_new;
> > @@ -3568,13 +3597,66 @@ unlock:
> > A  A  A  A return ret;
> > A }
> >
> > +static int mem_cgroup_oom_register_event(struct cgroup *cgrp,
> > + A  A  A  struct cftype *cft, struct eventfd_ctx *eventfd, const char *args)
> > +{
> > + A  A  A  struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp);
> > + A  A  A  struct mem_cgroup_eventfd_list *event;
> > + A  A  A  int type = MEMFILE_TYPE(cft->private);
> > + A  A  A  int ret = -ENOMEM;
> > +
> > + A  A  A  BUG_ON(type != _OOM_TYPE);
> > +
> > + A  A  A  mutex_lock(&memcg_oom_mutex);
> > +
> > + A  A  A  /* Allocate memory for new array of thresholds */
> 
> Irrelevant comment?
> 
> > + A  A  A  event = kmalloc(sizeof(*event), GFP_KERNEL);
> > + A  A  A  if (!event)
> > + A  A  A  A  A  A  A  goto unlock;
> > + A  A  A  /* Add new threshold */
> 
> Ditto.
> 
Ah...sorry for garbages..I'll clean these up.

Thanks,
-Kame

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>