Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758284Ab1EMIuc (ORCPT ); Fri, 13 May 2011 04:50:32 -0400 Received: from smtp-out.google.com ([74.125.121.67]:38384 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758154Ab1EMIu1 (ORCPT ); Fri, 13 May 2011 04:50:27 -0400 DomainKey-Signature: a=rsa-sha1; s=beta; d=google.com; c=nofws; q=dns; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references; b=St5fclD9tHEhIvv4nUiiEaH0u39O/34wCL66fF84ZiPFN5LNv90QZqrPlRwq2O898 mPpOcgXKjJS01LJ7V/3xw== From: Greg Thelen To: Andrew Morton Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, containers@lists.osdl.org, linux-fsdevel@vger.kernel.org, Andrea Righi , Balbir Singh , KAMEZAWA Hiroyuki , Daisuke Nishimura , Minchan Kim , Johannes Weiner , Ciju Rajan K , David Rientjes , Wu Fengguang , Vivek Goyal , Dave Chinner , Greg Thelen Subject: [RFC][PATCH v7 03/14] memcg: add mem_cgroup_mark_inode_dirty() Date: Fri, 13 May 2011 01:47:42 -0700 Message-Id: <1305276473-14780-4-git-send-email-gthelen@google.com> X-Mailer: git-send-email 1.7.3.1 In-Reply-To: <1305276473-14780-1-git-send-email-gthelen@google.com> References: <1305276473-14780-1-git-send-email-gthelen@google.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6720 Lines: 206 Create the mem_cgroup_mark_inode_dirty() routine, which is called when an inode is marked dirty. In kernels without memcg, this is an inline no-op. Add i_memcg field to struct address_space. When an inode is marked dirty with mem_cgroup_mark_inode_dirty(), the css_id of current memcg is recorded in i_memcg. Per-memcg writeback (introduced in a latter change) uses this field to isolate inodes associated with a particular memcg. The type of i_memcg is an 'unsigned short' because it stores the css_id of the memcg. Using a struct mem_cgroup pointer would be larger and also create a reference on the memcg which would hang memcg rmdir deletion. Usage of a css_id is not a reference so cgroup deletion is not affected. The memcg can be deleted without cleaning up the i_memcg field. When a memcg is deleted its pages are recharged to the cgroup parent, and the related inode(s) are marked as shared thus disassociating the inodes from the deleted cgroup. A mem_cgroup_mark_inode_dirty() tracepoint is also included to allow for easier understanding of memcg writeback operation. Signed-off-by: Greg Thelen --- fs/fs-writeback.c | 2 ++ fs/inode.c | 3 +++ include/linux/fs.h | 9 +++++++++ include/linux/memcontrol.h | 6 ++++++ include/trace/events/memcontrol.h | 32 ++++++++++++++++++++++++++++++++ mm/memcontrol.c | 24 ++++++++++++++++++++++++ 6 files changed, 76 insertions(+), 0 deletions(-) create mode 100644 include/trace/events/memcontrol.h diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 3392c29..0174fcf 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -19,6 +19,7 @@ #include #include #include +#include #include #include #include @@ -1111,6 +1112,7 @@ void __mark_inode_dirty(struct inode *inode, int flags) spin_lock(&bdi->wb.list_lock); inode->dirtied_when = jiffies; list_move(&inode->i_wb_list, &bdi->wb.b_dirty); + mem_cgroup_mark_inode_dirty(inode); spin_unlock(&bdi->wb.list_lock); if (wakeup_bdi) diff --git a/fs/inode.c b/fs/inode.c index ce61a1b..9ecb0bb 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -228,6 +228,9 @@ int inode_init_always(struct super_block *sb, struct inode *inode) mapping->assoc_mapping = NULL; mapping->backing_dev_info = &default_backing_dev_info; mapping->writeback_index = 0; +#ifdef CONFIG_CGROUP_MEM_RES_CTLR + mapping->i_memcg = 0; +#endif /* * If the block_device provides a backing_dev_info for client diff --git a/include/linux/fs.h b/include/linux/fs.h index 29c02f6..deabca3 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -645,6 +645,9 @@ struct address_space { spinlock_t private_lock; /* for use by the address_space */ struct list_head private_list; /* ditto */ struct address_space *assoc_mapping; /* ditto */ +#ifdef CONFIG_CGROUP_MEM_RES_CTLR + unsigned short i_memcg; /* css_id of memcg dirtier */ +#endif } __attribute__((aligned(sizeof(long)))); /* * On most architectures that alignment is already the case; but @@ -652,6 +655,12 @@ struct address_space { * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON. */ +/* + * When an address_space is shared by multiple memcg dirtieres, then i_memcg is + * set to this special, wildcard, css_id value (zero). + */ +#define I_MEMCG_SHARED 0 + struct block_device { dev_t bd_dev; /* not a kdev_t - it's a search key */ int bd_openers; diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 77e47f5..14b6d67 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -103,6 +103,8 @@ mem_cgroup_prepare_migration(struct page *page, extern void mem_cgroup_end_migration(struct mem_cgroup *mem, struct page *oldpage, struct page *newpage, bool migration_ok); +void mem_cgroup_mark_inode_dirty(struct inode *inode); + /* * For memory reclaim. */ @@ -273,6 +275,10 @@ static inline void mem_cgroup_end_migration(struct mem_cgroup *mem, { } +static inline void mem_cgroup_mark_inode_dirty(struct inode *inode) +{ +} + static inline int mem_cgroup_get_reclaim_priority(struct mem_cgroup *mem) { return 0; diff --git a/include/trace/events/memcontrol.h b/include/trace/events/memcontrol.h new file mode 100644 index 0000000..781ef9fc --- /dev/null +++ b/include/trace/events/memcontrol.h @@ -0,0 +1,32 @@ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM memcontrol + +#if !defined(_TRACE_MEMCONTROL_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_MEMCONTROL_H + +#include +#include + +TRACE_EVENT(mem_cgroup_mark_inode_dirty, + TP_PROTO(struct inode *inode), + + TP_ARGS(inode), + + TP_STRUCT__entry( + __field(unsigned long, ino) + __field(unsigned short, css_id) + ), + + TP_fast_assign( + __entry->ino = inode->i_ino; + __entry->css_id = + inode->i_mapping ? inode->i_mapping->i_memcg : 0; + ), + + TP_printk("ino=%ld css_id=%d", __entry->ino, __entry->css_id) +) + +#endif /* _TRACE_MEMCONTROL_H */ + +/* This part must be outside protection */ +#include diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 95aecca..3a792b7 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -54,6 +54,9 @@ #include +#define CREATE_TRACE_POINTS +#include + struct cgroup_subsys mem_cgroup_subsys __read_mostly; #define MEM_CGROUP_RECLAIM_RETRIES 5 struct mem_cgroup *root_mem_cgroup __read_mostly; @@ -1122,6 +1125,27 @@ static int calc_inactive_ratio(struct mem_cgroup *memcg, unsigned long *present_ return inactive_ratio; } +/* + * Mark the current task's memcg as the memcg associated with inode. Note: the + * recorded cgroup css_id is not guaranteed to remain correct. The current task + * may be moved to another cgroup. The memcg may also be deleted before the + * caller has time to use the i_memcg. + */ +void mem_cgroup_mark_inode_dirty(struct inode *inode) +{ + struct mem_cgroup *mem; + unsigned short id; + + rcu_read_lock(); + mem = mem_cgroup_from_task(current); + id = mem ? css_id(&mem->css) : 0; + rcu_read_unlock(); + + inode->i_mapping->i_memcg = id; + + trace_mem_cgroup_mark_inode_dirty(inode); +} + int mem_cgroup_inactive_anon_is_low(struct mem_cgroup *memcg) { unsigned long active; -- 1.7.3.1 -- 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/