Fixed one here. == From: KAMEZAWA Hiroyuki <[email protected]>
Now, at calculating dirty limit, vm_dirty_param() is called. This function returns dirty-limit related parameters considering memory cgroup settings. Now, assume that vm_dirty_bytes=100M (global dirty limit) and memory cgroup has 1G of pages and 40 dirty_ratio, dirtyable memory is 500MB. In this case, global_dirty_limits will consider dirty_limt as 500 *0.4 = 200MB. This is bad...memory cgroup is not back door. This patch limits the return value of vm_dirty_param() considring global settings. Changelog: - fixed an argument "mem" int to u64 - fixed to use global available memory to cap memcg's value. Signed-off-by: KAMEZAWA Hiroyuki <[email protected]> --- include/linux/memcontrol.h | 5 +++-- mm/memcontrol.c | 30 +++++++++++++++++++++++++++++- mm/page-writeback.c | 3 ++- 3 files changed, 34 insertions(+), 4 deletions(-) Index: dirty_limit_new/mm/memcontrol.c =================================================================== --- dirty_limit_new.orig/mm/memcontrol.c +++ dirty_limit_new/mm/memcontrol.c @@ -1171,9 +1171,11 @@ static void __mem_cgroup_dirty_param(str * can be moved after our access and writeback tends to take long time. At * least, "memcg" will not be freed while holding rcu_read_lock(). */ -void vm_dirty_param(struct vm_dirty_param *param) +void vm_dirty_param(struct vm_dirty_param *param, + u64 mem, u64 global) { struct mem_cgroup *memcg; + u64 limit, bglimit; if (mem_cgroup_disabled()) { global_vm_dirty_param(param); @@ -1183,6 +1185,32 @@ void vm_dirty_param(struct vm_dirty_para rcu_read_lock(); memcg = mem_cgroup_from_task(current); __mem_cgroup_dirty_param(param, memcg); + /* + * A limitation under memory cgroup is under global vm, too. + */ + if (vm_dirty_ratio) + limit = global * vm_dirty_ratio / 100; + else + limit = vm_dirty_bytes; + if (param->dirty_ratio) { + param->dirty_bytes = mem * param->dirty_ratio / 100; + param->dirty_ratio = 0; + } + if (param->dirty_bytes > limit) + param->dirty_bytes = limit; + + if (dirty_background_ratio) + bglimit = global * dirty_background_ratio / 100; + else + bglimit = dirty_background_bytes; + + if (param->dirty_background_ratio) { + param->dirty_background_bytes = + mem * param->dirty_background_ratio / 100; + param->dirty_background_ratio = 0; + } + if (param->dirty_background_bytes > bglimit) + param->dirty_background_bytes = bglimit; rcu_read_unlock(); } Index: dirty_limit_new/include/linux/memcontrol.h =================================================================== --- dirty_limit_new.orig/include/linux/memcontrol.h +++ dirty_limit_new/include/linux/memcontrol.h @@ -171,7 +171,7 @@ static inline void mem_cgroup_dec_page_s } bool mem_cgroup_has_dirty_limit(void); -void vm_dirty_param(struct vm_dirty_param *param); +void vm_dirty_param(struct vm_dirty_param *param, u64 mem, u64 global); s64 mem_cgroup_page_stat(enum mem_cgroup_nr_pages_item item); unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order, @@ -360,7 +360,8 @@ static inline bool mem_cgroup_has_dirty_ return false; } -static inline void vm_dirty_param(struct vm_dirty_param *param) +static inline void vm_dirty_param(struct vm_dirty_param *param, + u64 mem, u64 global) { global_vm_dirty_param(param); } Index: dirty_limit_new/mm/page-writeback.c =================================================================== --- dirty_limit_new.orig/mm/page-writeback.c +++ dirty_limit_new/mm/page-writeback.c @@ -466,7 +466,8 @@ void global_dirty_limits(unsigned long * struct task_struct *tsk; struct vm_dirty_param dirty_param; - vm_dirty_param(&dirty_param); + vm_dirty_param(&dirty_param, + available_memory, global_dirtyable_memory()); if (dirty_param.dirty_bytes) dirty = DIV_ROUND_UP(dirty_param.dirty_bytes, PAGE_SIZE); _______________________________________________ Containers mailing list [email protected] https://lists.linux-foundation.org/mailman/listinfo/containers _______________________________________________ Devel mailing list [email protected] https://openvz.org/mailman/listinfo/devel
