Add memory.low_wmark_distance, memory.high_wmark_distance and reclaim_wmarks APIs per-memcg. The first two adjust the internal low/high wmark calculation and the reclaim_wmarks exports the current value of watermarks. By default, the low/high_wmark is calculated by subtracting the distance from the hard_limit(limit_in_bytes). When configuring the low/high_wmark distance, user must setup the high_wmark_distance before low_wmark_distance. Also user must zero low_wmark_distance before high_wmark_distance. $ echo 500m >/dev/cgroup/A/memory.limit_in_bytes $ cat /dev/cgroup/A/memory.limit_in_bytes 524288000 $ echo 50m >/dev/cgroup/A/memory.high_wmark_distance $ echo 40m >/dev/cgroup/A/memory.low_wmark_distance $ cat /dev/cgroup/A/memory.reclaim_wmarks low_wmark 482344960 high_wmark 471859200 change v5..v4 1. add sanity check for setting high/low_wmark_distance for root cgroup. changelog v4..v3: 1. replace the "wmark_ratio" API with individual tunable for low/high_wmarks. changelog v3..v2: 1. replace the "min_free_kbytes" api with "wmark_ratio". This is part of feedbacks Signed-off-by: Ying Han <yinghan@xxxxxxxxxx> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> --- mm/memcontrol.c | 101 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 101 insertions(+), 0 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index c351e62..6029f1b 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3974,6 +3974,78 @@ static int mem_cgroup_swappiness_write(struct cgroup *cgrp, struct cftype *cft, return 0; } +static u64 mem_cgroup_high_wmark_distance_read(struct cgroup *cgrp, + struct cftype *cft) +{ + struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); + + return memcg->high_wmark_distance; +} + +static u64 mem_cgroup_low_wmark_distance_read(struct cgroup *cgrp, + struct cftype *cft) +{ + struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp); + + return memcg->low_wmark_distance; +} + +static int mem_cgroup_high_wmark_distance_write(struct cgroup *cont, + struct cftype *cft, + const char *buffer) +{ + struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); + u64 low_wmark_distance = memcg->low_wmark_distance; + unsigned long long val; + u64 limit; + int ret; + + if (!cont->parent) + return -EINVAL; + + ret = res_counter_memparse_write_strategy(buffer, &val); + if (ret) + return -EINVAL; + + limit = res_counter_read_u64(&memcg->res, RES_LIMIT); + if ((val >= limit) || (val < low_wmark_distance) || + (low_wmark_distance && val == low_wmark_distance)) + return -EINVAL; + + memcg->high_wmark_distance = val; + + setup_per_memcg_wmarks(memcg); + return 0; +} + +static int mem_cgroup_low_wmark_distance_write(struct cgroup *cont, + struct cftype *cft, + const char *buffer) +{ + struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); + u64 high_wmark_distance = memcg->high_wmark_distance; + unsigned long long val; + u64 limit; + int ret; + + if (!cont->parent) + return -EINVAL; + + ret = res_counter_memparse_write_strategy(buffer, &val); + if (ret) + return -EINVAL; + + limit = res_counter_read_u64(&memcg->res, RES_LIMIT); + if ((val >= limit) || (val > high_wmark_distance) || + (high_wmark_distance && val == high_wmark_distance)) + return -EINVAL; + + memcg->low_wmark_distance = val; + + setup_per_memcg_wmarks(memcg); + return 0; +} + static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap) { struct mem_cgroup_threshold_ary *t; @@ -4265,6 +4337,21 @@ static void mem_cgroup_oom_unregister_event(struct cgroup *cgrp, mutex_unlock(&memcg_oom_mutex); } +static int mem_cgroup_wmark_read(struct cgroup *cgrp, + struct cftype *cft, struct cgroup_map_cb *cb) +{ + struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp); + u64 low_wmark, high_wmark; + + low_wmark = res_counter_read_u64(&mem->res, RES_LOW_WMARK_LIMIT); + high_wmark = res_counter_read_u64(&mem->res, RES_HIGH_WMARK_LIMIT); + + cb->fill(cb, "low_wmark", low_wmark); + cb->fill(cb, "high_wmark", high_wmark); + + return 0; +} + static int mem_cgroup_oom_control_read(struct cgroup *cgrp, struct cftype *cft, struct cgroup_map_cb *cb) { @@ -4368,6 +4455,20 @@ static struct cftype mem_cgroup_files[] = { .unregister_event = mem_cgroup_oom_unregister_event, .private = MEMFILE_PRIVATE(_OOM_TYPE, OOM_CONTROL), }, + { + .name = "high_wmark_distance", + .write_string = mem_cgroup_high_wmark_distance_write, + .read_u64 = mem_cgroup_high_wmark_distance_read, + }, + { + .name = "low_wmark_distance", + .write_string = mem_cgroup_low_wmark_distance_write, + .read_u64 = mem_cgroup_low_wmark_distance_read, + }, + { + .name = "reclaim_wmarks", + .read_map = mem_cgroup_wmark_read, + }, }; #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP -- 1.7.3.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>