Create a daemon which does background page reclaim. This daemon * starts when usage > high_watermark * stops when usage < low_watermark. Because kthread_run() cannot be used when init_mem_cgroup is initialized(Sigh), thread for init_mem_cgroup is invoked later by initcall. Changes from YAMAMOTO-san's version * use kthread instead of workqueue. Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> From: YAMAMOTO Takashi <yamamoto@xxxxxxxxxxxxx> mm/memcontrol.c | 79 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 79 insertions(+) Index: linux-2.6.24-rc3-mm1/mm/memcontrol.c =================================================================== --- linux-2.6.24-rc3-mm1.orig/mm/memcontrol.c 2007-11-28 16:44:57.000000000 +0900 +++ linux-2.6.24-rc3-mm1/mm/memcontrol.c 2007-11-28 17:21:57.000000000 +0900 @@ -30,6 +30,8 @@ #include <linux/spinlock.h> #include <linux/fs.h> #include <linux/seq_file.h> +#include <linux/kthread.h> +#include <linux/freezer.h> #include <asm/uaccess.h> @@ -122,6 +124,13 @@ */ struct res_counter res; /* + * background reclaim + */ + struct { + wait_queue_head_t waitq; + struct task_struct *thread; + } daemon; + /* * Per cgroup active and inactive list, similar to the * per zone LRU lists. */ @@ -401,6 +410,17 @@ } } +static void +mem_cgroup_schedule_reclaim(struct mem_cgroup *mem) +{ + if (!unlikely(mem->daemon.thread)) + return; + if (!waitqueue_active(&mem->daemon.waitq)) + return; + wake_up_interruptible(&mem->daemon.waitq); +} + + int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *mem) { int ret; @@ -677,6 +697,8 @@ mem_cgroup_out_of_memory(mem, GFP_KERNEL); goto free_pc; } + if (res_counter_above_high_watermark(&mem->res)) + mem_cgroup_schedule_reclaim(mem); atomic_set(&pc->ref_cnt, 1); pc->mem_cgroup = mem; @@ -832,6 +854,38 @@ } /* + * Background page reclaim daeom for memory controller. + */ + +static int mem_cgroup_reclaim_daemon(void *data) +{ + DEFINE_WAIT(wait); + struct mem_cgroup *mem = data; + + css_get(&mem->css); + set_freezable(); + + while (!kthread_should_stop()) { + prepare_to_wait(&mem->daemon.waitq, &wait, TASK_INTERRUPTIBLE); + + if (res_counter_below_low_watermark(&mem->res)) { + if (!kthread_should_stop()) { + schedule(); + try_to_freeze(); + } + finish_wait(&mem->daemon.waitq, &wait); + continue; + } + finish_wait(&mem->daemon.waitq, &wait); + try_to_free_mem_cgroup_pages(mem, GFP_HIGHUSER_MOVABLE); + } + + css_put(&mem->css); + + return 0; +} + +/* * This routine traverse page_cgroup in given list and drop them all. * This routine ignores page_cgroup->ref_cnt. * *And* this routine doesn't reclaim page itself, just removes page_cgroup. @@ -1045,6 +1100,7 @@ { struct mem_cgroup *mem = mem_cgroup_from_cont(cont); int ret; + ret = mem_cgroup_force_empty(mem); if (!ret) ret = nbytes; @@ -1188,6 +1244,16 @@ static struct mem_cgroup init_mem_cgroup; +static int __init mem_cgroup_reclaim_init(void) +{ + init_mem_cgroup.daemon.thread = kthread_run(mem_cgroup_reclaim_daemon, + &init_mem_cgroup, "memcontd"); + if (IS_ERR(init_mem_cgroup.daemon.thread)) + BUG(); + return 0; +} +late_initcall(mem_cgroup_reclaim_init); + static struct cgroup_subsys_state * mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont) { @@ -1212,6 +1278,17 @@ if (alloc_mem_cgroup_per_zone_info(mem, node)) goto free_out; + /* Memory Reclaim Daemon per cgroup */ + init_waitqueue_head(&mem->daemon.waitq); + if (mem != &init_mem_cgroup) { + /* Complicated...but we cannot call kthread create here..*/ + /* init call will later assign kthread */ + mem->daemon.thread = kthread_run(mem_cgroup_reclaim_daemon, + mem, "memcontd"); + if (IS_ERR(mem->daemon.thread)) + goto free_out; + } + return &mem->css; free_out: for_each_node_state(node, N_POSSIBLE) @@ -1226,6 +1303,7 @@ { struct mem_cgroup *mem = mem_cgroup_from_cont(cont); mem_cgroup_force_empty(mem); + kthread_stop(mem->daemon.thread); } static void mem_cgroup_destroy(struct cgroup_subsys *ss, _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers