From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753967Ab0CBWZF (ORCPT ); Tue, 2 Mar 2010 17:25:05 -0500 Received: from trinity.develer.com ([83.149.158.210]:35739 "EHLO trinity.develer.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753615Ab0CBWZB (ORCPT ); Tue, 2 Mar 2010 17:25:01 -0500 Date: Tue, 2 Mar 2010 23:24:55 +0100 From: Andrea Righi To: Greg Thelen Cc: Balbir Singh , KAMEZAWA Hiroyuki , Suleiman Souhlal , Daisuke Nishimura , "Kirill A. Shutemov" , Andrew Morton , containers@lists.linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH -mmotm 2/3] memcg: dirty pages accounting and limiting infrastructure Message-ID: <20100302222455.GE2369@linux> References: <1267478620-5276-1-git-send-email-arighi@develer.com> <1267478620-5276-3-git-send-email-arighi@develer.com> <49b004811003021008t4fae71bbu8d56192e48c32f39@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <49b004811003021008t4fae71bbu8d56192e48c32f39@mail.gmail.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 02, 2010 at 10:08:17AM -0800, Greg Thelen wrote: > Comments below. Yet to be tested on my end, but I will test it. > > On Mon, Mar 1, 2010 at 1:23 PM, Andrea Righi wrote: > > Infrastructure to account dirty pages per cgroup and add dirty limit > > interfaces in the cgroupfs: > > > >  - Direct write-out: memory.dirty_ratio, memory.dirty_bytes > > > >  - Background write-out: memory.dirty_background_ratio, memory.dirty_background_bytes > > > > Signed-off-by: Andrea Righi > > --- > >  include/linux/memcontrol.h |   77 ++++++++++- > >  mm/memcontrol.c            |  336 ++++++++++++++++++++++++++++++++++++++++---- > >  2 files changed, 384 insertions(+), 29 deletions(-) > > > > diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h > > index 1f9b119..cc88b2e 100644 > > --- a/include/linux/memcontrol.h > > +++ b/include/linux/memcontrol.h > > @@ -19,12 +19,50 @@ > > > >  #ifndef _LINUX_MEMCONTROL_H > >  #define _LINUX_MEMCONTROL_H > > + > > +#include > >  #include > > + > >  struct mem_cgroup; > >  struct page_cgroup; > >  struct page; > >  struct mm_struct; > > > > +/* Cgroup memory statistics items exported to the kernel */ > > +enum mem_cgroup_page_stat_item { > > +       MEMCG_NR_DIRTYABLE_PAGES, > > +       MEMCG_NR_RECLAIM_PAGES, > > +       MEMCG_NR_WRITEBACK, > > +       MEMCG_NR_DIRTY_WRITEBACK_PAGES, > > +}; > > + > > +/* > > + * Statistics for memory cgroup. > > + */ > > +enum mem_cgroup_stat_index { > > +       /* > > +        * For MEM_CONTAINER_TYPE_ALL, usage = pagecache + rss. > > +        */ > > +       MEM_CGROUP_STAT_CACHE,     /* # of pages charged as cache */ > > +       MEM_CGROUP_STAT_RSS,       /* # of pages charged as anon rss */ > > +       MEM_CGROUP_STAT_FILE_MAPPED,  /* # of pages charged as file rss */ > > +       MEM_CGROUP_STAT_PGPGIN_COUNT,   /* # of pages paged in */ > > +       MEM_CGROUP_STAT_PGPGOUT_COUNT,  /* # of pages paged out */ > > +       MEM_CGROUP_STAT_EVENTS, /* sum of pagein + pageout for internal use */ > > +       MEM_CGROUP_STAT_SWAPOUT, /* # of pages, swapped out */ > > +       MEM_CGROUP_STAT_SOFTLIMIT, /* decrements on each page in/out. > > +                                       used by soft limit implementation */ > > +       MEM_CGROUP_STAT_THRESHOLDS, /* decrements on each page in/out. > > +                                       used by threshold implementation */ > > +       MEM_CGROUP_STAT_FILE_DIRTY,   /* # of dirty pages in page cache */ > > +       MEM_CGROUP_STAT_WRITEBACK,   /* # of pages under writeback */ > > +       MEM_CGROUP_STAT_WRITEBACK_TEMP,   /* # of pages under writeback using > > +                                               temporary buffers */ > > +       MEM_CGROUP_STAT_UNSTABLE_NFS,   /* # of NFS unstable pages */ > > + > > +       MEM_CGROUP_STAT_NSTATS, > > +}; > > + > >  #ifdef CONFIG_CGROUP_MEM_RES_CTLR > >  /* > >  * All "charge" functions with gfp_mask should use GFP_KERNEL or > > @@ -117,6 +155,13 @@ extern void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, > >  extern int do_swap_account; > >  #endif > > > > +extern long mem_cgroup_dirty_ratio(void); > > +extern unsigned long mem_cgroup_dirty_bytes(void); > > +extern long mem_cgroup_dirty_background_ratio(void); > > +extern unsigned long mem_cgroup_dirty_background_bytes(void); > > + > > +extern s64 mem_cgroup_page_stat(enum mem_cgroup_page_stat_item item); > > + > >  static inline bool mem_cgroup_disabled(void) > >  { > >        if (mem_cgroup_subsys.disabled) > > @@ -125,7 +170,8 @@ static inline bool mem_cgroup_disabled(void) > >  } > > > >  extern bool mem_cgroup_oom_called(struct task_struct *task); > > -void mem_cgroup_update_file_mapped(struct page *page, int val); > > +void mem_cgroup_update_stat(struct page *page, > > +                       enum mem_cgroup_stat_index idx, int val); > >  unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order, > >                                                gfp_t gfp_mask, int nid, > >                                                int zid); > > @@ -300,8 +346,8 @@ mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p) > >  { > >  } > > > > -static inline void mem_cgroup_update_file_mapped(struct page *page, > > -                                                       int val) > > +static inline void mem_cgroup_update_stat(struct page *page, > > +                       enum mem_cgroup_stat_index idx, int val) > >  { > >  } > > > > @@ -312,6 +358,31 @@ unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order, > >        return 0; > >  } > > > > +static inline long mem_cgroup_dirty_ratio(void) > > +{ > > +       return vm_dirty_ratio; > > +} > > + > > +static inline unsigned long mem_cgroup_dirty_bytes(void) > > +{ > > +       return vm_dirty_bytes; > > +} > > + > > +static inline long mem_cgroup_dirty_background_ratio(void) > > +{ > > +       return dirty_background_ratio; > > +} > > + > > +static inline unsigned long mem_cgroup_dirty_background_bytes(void) > > +{ > > +       return dirty_background_bytes; > > +} > > + > > +static inline s64 mem_cgroup_page_stat(enum mem_cgroup_page_stat_item item) > > +{ > > +       return -ENOMEM; > > +} > > + > >  #endif /* CONFIG_CGROUP_MEM_CONT */ > > > >  #endif /* _LINUX_MEMCONTROL_H */ > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > > index a443c30..e74cf66 100644 > > --- a/mm/memcontrol.c > > +++ b/mm/memcontrol.c > > @@ -66,31 +66,16 @@ static int really_do_swap_account __initdata = 1; /* for remember boot option*/ > >  #define SOFTLIMIT_EVENTS_THRESH (1000) > >  #define THRESHOLDS_EVENTS_THRESH (100) > > > > -/* > > - * Statistics for memory cgroup. > > - */ > > -enum mem_cgroup_stat_index { > > -       /* > > -        * For MEM_CONTAINER_TYPE_ALL, usage = pagecache + rss. > > -        */ > > -       MEM_CGROUP_STAT_CACHE,     /* # of pages charged as cache */ > > -       MEM_CGROUP_STAT_RSS,       /* # of pages charged as anon rss */ > > -       MEM_CGROUP_STAT_FILE_MAPPED,  /* # of pages charged as file rss */ > > -       MEM_CGROUP_STAT_PGPGIN_COUNT,   /* # of pages paged in */ > > -       MEM_CGROUP_STAT_PGPGOUT_COUNT,  /* # of pages paged out */ > > -       MEM_CGROUP_STAT_SWAPOUT, /* # of pages, swapped out */ > > -       MEM_CGROUP_STAT_SOFTLIMIT, /* decrements on each page in/out. > > -                                       used by soft limit implementation */ > > -       MEM_CGROUP_STAT_THRESHOLDS, /* decrements on each page in/out. > > -                                       used by threshold implementation */ > > - > > -       MEM_CGROUP_STAT_NSTATS, > > -}; > > - > >  struct mem_cgroup_stat_cpu { > >        s64 count[MEM_CGROUP_STAT_NSTATS]; > >  }; > > > > +/* Per cgroup page statistics */ > > +struct mem_cgroup_page_stat { > > +       enum mem_cgroup_page_stat_item item; > > +       s64 value; > > +}; > > + > >  /* > >  * per-zone information in memory controller. > >  */ > > @@ -157,6 +142,15 @@ struct mem_cgroup_threshold_ary { > >  static bool mem_cgroup_threshold_check(struct mem_cgroup *mem); > >  static void mem_cgroup_threshold(struct mem_cgroup *mem); > > > > +enum mem_cgroup_dirty_param { > > +       MEM_CGROUP_DIRTY_RATIO, > > +       MEM_CGROUP_DIRTY_BYTES, > > +       MEM_CGROUP_DIRTY_BACKGROUND_RATIO, > > +       MEM_CGROUP_DIRTY_BACKGROUND_BYTES, > > + > > +       MEM_CGROUP_DIRTY_NPARAMS, > > +}; > > + > >  /* > >  * The memory controller data structure. The memory controller controls both > >  * page cache and RSS per cgroup. We would eventually like to provide > > @@ -205,6 +199,9 @@ struct mem_cgroup { > > > >        unsigned int    swappiness; > > > > +       /* control memory cgroup dirty pages */ > > +       unsigned long dirty_param[MEM_CGROUP_DIRTY_NPARAMS]; > > + > >        /* set when res.limit == memsw.limit */ > >        bool            memsw_is_minimum; > > > > @@ -1021,6 +1018,164 @@ static unsigned int get_swappiness(struct mem_cgroup *memcg) > >        return swappiness; > >  } > > > > +static unsigned long get_dirty_param(struct mem_cgroup *memcg, > > +                       enum mem_cgroup_dirty_param idx) > > +{ > > +       unsigned long ret; > > + > > +       VM_BUG_ON(idx >= MEM_CGROUP_DIRTY_NPARAMS); > > +       spin_lock(&memcg->reclaim_param_lock); > > +       ret = memcg->dirty_param[idx]; > > +       spin_unlock(&memcg->reclaim_param_lock); > > + > > +       return ret; > > +} > > + > > > +long mem_cgroup_dirty_ratio(void) > > +{ > > +       struct mem_cgroup *memcg; > > +       long ret = vm_dirty_ratio; > > + > > +       if (mem_cgroup_disabled()) > > +               return ret; > > +       /* > > +        * It's possible that "current" may be moved to other cgroup while we > > +        * access cgroup. But precise check is meaningless because the task can > > +        * be moved after our access and writeback tends to take long time. > > +        * At least, "memcg" will not be freed under rcu_read_lock(). > > +        */ > > +       rcu_read_lock(); > > +       memcg = mem_cgroup_from_task(current); > > +       if (likely(memcg)) > > +               ret = get_dirty_param(memcg, MEM_CGROUP_DIRTY_RATIO); > > +       rcu_read_unlock(); > > + > > +       return ret; > > +} > > + > > +unsigned long mem_cgroup_dirty_bytes(void) > > +{ > > +       struct mem_cgroup *memcg; > > +       unsigned long ret = vm_dirty_bytes; > > + > > +       if (mem_cgroup_disabled()) > > +               return ret; > > +       rcu_read_lock(); > > +       memcg = mem_cgroup_from_task(current); > > +       if (likely(memcg)) > > +               ret = get_dirty_param(memcg, MEM_CGROUP_DIRTY_BYTES); > > +       rcu_read_unlock(); > > + > > +       return ret; > > +} > > + > > +long mem_cgroup_dirty_background_ratio(void) > > +{ > > +       struct mem_cgroup *memcg; > > +       long ret = dirty_background_ratio; > > + > > +       if (mem_cgroup_disabled()) > > +               return ret; > > +       rcu_read_lock(); > > +       memcg = mem_cgroup_from_task(current); > > +       if (likely(memcg)) > > +               ret = get_dirty_param(memcg, MEM_CGROUP_DIRTY_BACKGROUND_RATIO); > > +       rcu_read_unlock(); > > + > > +       return ret; > > +} > > + > > +unsigned long mem_cgroup_dirty_background_bytes(void) > > +{ > > +       struct mem_cgroup *memcg; > > +       unsigned long ret = dirty_background_bytes; > > + > > +       if (mem_cgroup_disabled()) > > +               return ret; > > +       rcu_read_lock(); > > +       memcg = mem_cgroup_from_task(current); > > +       if (likely(memcg)) > > +               ret = get_dirty_param(memcg, MEM_CGROUP_DIRTY_BACKGROUND_BYTES); > > +       rcu_read_unlock(); > > + > > +       return ret; > > +} > > Given that mem_cgroup_dirty_[background_]{ratio,bytes}() are similar, > should we refactor the majority of them into a single routine? Agreed. Thanks, -Andrea