Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753369Ab0BUV24 (ORCPT ); Sun, 21 Feb 2010 16:28:56 -0500 Received: from smtp-out.google.com ([216.239.44.51]:51623 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752990Ab0BUV2y (ORCPT ); Sun, 21 Feb 2010 16:28:54 -0500 DomainKey-Signature: a=rsa-sha1; s=beta; d=google.com; c=nofws; q=dns; h=date:from:x-x-sender:to:cc:subject:in-reply-to:message-id: references:user-agent:mime-version:content-type:x-system-of-record; b=A9IGRa12i8QUDM33K9IiWkxAtZnLS1VCfUlkU6aQR/dj0Jm0cCxkKR5x36jnAjgHB Vk000rm6GKjo0QwgU9GiA== Date: Sun, 21 Feb 2010 13:28:35 -0800 (PST) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com To: Andrea Righi cc: Balbir Singh , KAMEZAWA Hiroyuki , Suleiman Souhlal , Vivek Goyal , Andrew Morton , containers@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] memcg: dirty pages accounting and limiting infrastructure In-Reply-To: <1266765525-30890-2-git-send-email-arighi@develer.com> Message-ID: References: <1266765525-30890-1-git-send-email-arighi@develer.com> <1266765525-30890-2-git-send-email-arighi@develer.com> User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-System-Of-Record: true Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7193 Lines: 246 On Sun, 21 Feb 2010, Andrea Righi wrote: > diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h > index 1f9b119..ba3fe0d 100644 > --- a/include/linux/memcontrol.h > +++ b/include/linux/memcontrol.h > @@ -25,6 +25,16 @@ struct page_cgroup; > struct page; > struct mm_struct; > > +/* Cgroup memory statistics items exported to the kernel */ > +enum memcg_page_stat_item { > + MEMCG_NR_FREE_PAGES, > + MEMCG_NR_RECLAIMABLE_PAGES, > + MEMCG_NR_FILE_DIRTY, > + MEMCG_NR_WRITEBACK, > + MEMCG_NR_WRITEBACK_TEMP, > + MEMCG_NR_UNSTABLE_NFS, > +}; > + > #ifdef CONFIG_CGROUP_MEM_RES_CTLR > /* > * All "charge" functions with gfp_mask should use GFP_KERNEL or > @@ -48,6 +58,8 @@ extern void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *ptr); > > extern int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm, > gfp_t gfp_mask); > +extern void mem_cgroup_charge_dirty(struct page *page, > + enum zone_stat_item idx, int charge); > extern void mem_cgroup_add_lru_list(struct page *page, enum lru_list lru); > extern void mem_cgroup_del_lru_list(struct page *page, enum lru_list lru); > extern void mem_cgroup_rotate_lru_list(struct page *page, enum lru_list lru); > @@ -117,6 +129,10 @@ extern void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, > extern int do_swap_account; > #endif > > +extern unsigned long mem_cgroup_dirty_bytes(void); > + > +extern u64 mem_cgroup_page_state(enum memcg_page_stat_item item); > + > static inline bool mem_cgroup_disabled(void) > { > if (mem_cgroup_subsys.disabled) > @@ -144,6 +160,11 @@ static inline int mem_cgroup_cache_charge(struct page *page, > return 0; > } > > +static inline void mem_cgroup_charge_dirty(struct page *page, > + enum zone_stat_item idx, int charge) > +{ > +} > + > static inline int mem_cgroup_try_charge_swapin(struct mm_struct *mm, > struct page *page, gfp_t gfp_mask, struct mem_cgroup **ptr) > { > @@ -312,6 +333,16 @@ unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order, > return 0; > } > > +static inline unsigned long mem_cgroup_dirty_bytes(void) > +{ > + return vm_dirty_bytes; > +} > + > +static inline u64 mem_cgroup_page_state(enum memcg_page_stat_item item) > +{ > + return 0; > +} > + > #endif /* CONFIG_CGROUP_MEM_CONT */ > > #endif /* _LINUX_MEMCONTROL_H */ > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index 954032b..288b9a4 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -64,13 +64,18 @@ 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_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_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, > }; > @@ -225,6 +230,9 @@ struct mem_cgroup { > /* set when res.limit == memsw.limit */ > bool memsw_is_minimum; > > + /* control memory cgroup dirty pages */ > + unsigned long dirty_bytes; > + > /* > * statistics. This must be placed at the end of memcg. > */ > @@ -519,6 +527,67 @@ static void mem_cgroup_charge_statistics(struct mem_cgroup *mem, > put_cpu(); > } > > +static struct mem_cgroup *get_mem_cgroup_from_page(struct page *page) > +{ > + struct page_cgroup *pc; > + struct mem_cgroup *mem = NULL; > + > + pc = lookup_page_cgroup(page); > + if (unlikely(!pc)) > + return NULL; > + lock_page_cgroup(pc); > + if (PageCgroupUsed(pc)) { > + mem = pc->mem_cgroup; > + if (mem) > + css_get(&mem->css); > + } > + unlock_page_cgroup(pc); > + return mem; > +} Is it possible to merge this with try_get_mem_cgroup_from_page()? > + > +void mem_cgroup_charge_dirty(struct page *page, > + enum zone_stat_item idx, int charge) > +{ > + struct mem_cgroup *mem; > + struct mem_cgroup_stat_cpu *cpustat; > + unsigned long flags; > + int cpu; > + > + if (mem_cgroup_disabled()) > + return; > + /* Translate the zone_stat_item into a mem_cgroup_stat_index */ > + switch (idx) { > + case NR_FILE_DIRTY: > + idx = MEM_CGROUP_STAT_FILE_DIRTY; > + break; > + case NR_WRITEBACK: > + idx = MEM_CGROUP_STAT_WRITEBACK; > + break; > + case NR_WRITEBACK_TEMP: > + idx = MEM_CGROUP_STAT_WRITEBACK_TEMP; > + break; > + case NR_UNSTABLE_NFS: > + idx = MEM_CGROUP_STAT_UNSTABLE_NFS; > + break; > + default: > + return; WARN()? We don't want to silently leak counters. > + } > + /* Charge the memory cgroup statistics */ > + mem = get_mem_cgroup_from_page(page); > + if (!mem) { > + mem = root_mem_cgroup; > + css_get(&mem->css); > + } get_mem_cgroup_from_page() should probably handle the root_mem_cgroup case and return a reference from it. > + > + local_irq_save(flags); > + cpu = get_cpu(); > + cpustat = &mem->stat.cpustat[cpu]; > + __mem_cgroup_stat_add_safe(cpustat, idx, charge); get_cpu()? Preemption is already disabled, just use smp_processor_id(). > + put_cpu(); > + local_irq_restore(flags); > + css_put(&mem->css); > +} > + > static unsigned long mem_cgroup_get_local_zonestat(struct mem_cgroup *mem, > enum lru_list idx) > { > @@ -992,6 +1061,97 @@ static unsigned int get_swappiness(struct mem_cgroup *memcg) > return swappiness; > } > > +static unsigned long get_dirty_bytes(struct mem_cgroup *memcg) > +{ > + struct cgroup *cgrp = memcg->css.cgroup; > + unsigned long dirty_bytes; > + > + /* root ? */ > + if (cgrp->parent == NULL) > + return vm_dirty_bytes; > + > + spin_lock(&memcg->reclaim_param_lock); > + dirty_bytes = memcg->dirty_bytes; > + spin_unlock(&memcg->reclaim_param_lock); > + > + return dirty_bytes; > +} > + > +unsigned long mem_cgroup_dirty_bytes(void) > +{ > + struct mem_cgroup *memcg; > + unsigned long dirty_bytes; > + > + if (mem_cgroup_disabled()) > + return vm_dirty_bytes; > + > + rcu_read_lock(); > + memcg = mem_cgroup_from_task(current); > + if (memcg == NULL) > + dirty_bytes = vm_dirty_bytes; > + else > + dirty_bytes = get_dirty_bytes(memcg); > + rcu_read_unlock(); The rcu_read_lock() isn't protecting anything here. > + > + return dirty_bytes; > +} > + > +u64 mem_cgroup_page_state(enum memcg_page_stat_item item) > +{ > + struct mem_cgroup *memcg; > + struct cgroup *cgrp; > + u64 ret = 0; > + > + if (mem_cgroup_disabled()) > + return 0; > + > + rcu_read_lock(); Again, this isn't necessary. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/