From 841710aa6e4acd066ab9fe8c8cb6f4e4e6709d83 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 22 May 2015 18:23:33 -0400 Subject: writeback: implement memcg wb_domain Dirtyable memory is distributed to a wb (bdi_writeback) according to the relative bandwidth the wb is writing out in the whole system. This distribution is global - each wb is measured against all other wb's and gets the proportinately sized portion of the memory in the whole system. For cgroup writeback, the amount of dirtyable memory is scoped by memcg and thus each wb would need to be measured and controlled in its memcg. IOW, a wb will belong to two writeback domains - the global and memcg domains. The previous patches laid the groundwork to support the two wb_domains and this patch implements memcg wb_domain. memcg->cgwb_domain is initialized on css online and destroyed on css release, wb->memcg_completions is added, and __wb_writeout_inc() is updated to increment completions against both global and memcg wb_domains. The following patches will update balance_dirty_pages() and its subroutines to actually consider memcg wb_domain for throttling. Signed-off-by: Tejun Heo Cc: Jens Axboe Cc: Jan Kara Cc: Wu Fengguang Cc: Greg Thelen Signed-off-by: Jens Axboe --- include/linux/backing-dev-defs.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/backing-dev-defs.h') diff --git a/include/linux/backing-dev-defs.h b/include/linux/backing-dev-defs.h index 97a92fa0cdb5..8d470b73824f 100644 --- a/include/linux/backing-dev-defs.h +++ b/include/linux/backing-dev-defs.h @@ -118,6 +118,7 @@ struct bdi_writeback { #ifdef CONFIG_CGROUP_WRITEBACK struct percpu_ref refcnt; /* used only for !root wb's */ + struct fprop_local_percpu memcg_completions; struct cgroup_subsys_state *memcg_css; /* the associated memcg */ struct cgroup_subsys_state *blkcg_css; /* and blkcg */ struct list_head memcg_node; /* anchored at memcg->cgwb_list */ -- cgit v1.2.3