The patch titled
Subject: mm: memcg: add per-memcg zswap writeback stat
has been added to the -mm mm-unstable branch. Its filename is
mm-memcg-add-per-memcg-zswap-writeback-stat.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-memcg-add-per-memcg-zswap-writeback-stat.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Domenico Cerasuolo <cerasuolodomenico@xxxxxxxxx>
Subject: mm: memcg: add per-memcg zswap writeback stat
Date: Tue, 17 Oct 2023 16:21:50 -0700
Since zswap now writes back pages from memcg-specific LRUs, we now need a
new stat to show writebacks count for each memcg.
Link: https://lkml.kernel.org/r/20231017232152.2605440-4-nphamcs@xxxxxxxxx
Suggested-by: Nhat Pham <nphamcs@xxxxxxxxx>
Signed-off-by: Domenico Cerasuolo <cerasuolodomenico@xxxxxxxxx>
Signed-off-by: Nhat Pham <nphamcs@xxxxxxxxx>
Cc: Dan Streetman <ddstreet@xxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Cc: Muchun Song <muchun.song@xxxxxxxxx>
Cc: Roman Gushchin <roman.gushchin@xxxxxxxxx>
Cc: Seth Jennings <sjenning@xxxxxxxxxx>
Cc: Shakeel Butt <shakeelb@xxxxxxxxxx>
Cc: Shuah Khan <shuah@xxxxxxxxxx>
Cc: Vitaly Wool <vitaly.wool@xxxxxxxxxxxx>
Cc: Yosry Ahmed <yosryahmed@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/memcontrol.h | 2 ++
mm/memcontrol.c | 15 +++++++++++++++
mm/zswap.c | 3 +++
3 files changed, 20 insertions(+)
--- a/include/linux/memcontrol.h~mm-memcg-add-per-memcg-zswap-writeback-stat
+++ a/include/linux/memcontrol.h
@@ -38,6 +38,7 @@ enum memcg_stat_item {
MEMCG_KMEM,
MEMCG_ZSWAP_B,
MEMCG_ZSWAPPED,
+ MEMCG_ZSWAP_WB,
MEMCG_NR_STAT,
};
@@ -1884,6 +1885,7 @@ static inline void count_objcg_event(str
bool obj_cgroup_may_zswap(struct obj_cgroup *objcg);
void obj_cgroup_charge_zswap(struct obj_cgroup *objcg, size_t size);
void obj_cgroup_uncharge_zswap(struct obj_cgroup *objcg, size_t size);
+void obj_cgroup_report_zswap_wb(struct obj_cgroup *objcg);
#else
static inline bool obj_cgroup_may_zswap(struct obj_cgroup *objcg)
{
--- a/mm/memcontrol.c~mm-memcg-add-per-memcg-zswap-writeback-stat
+++ a/mm/memcontrol.c
@@ -1521,6 +1521,7 @@ static const struct memory_stat memory_s
#if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP)
{ "zswap", MEMCG_ZSWAP_B },
{ "zswapped", MEMCG_ZSWAPPED },
+ { "zswap_wb", MEMCG_ZSWAP_WB },
#endif
{ "file_mapped", NR_FILE_MAPPED },
{ "file_dirty", NR_FILE_DIRTY },
@@ -1557,6 +1558,7 @@ static int memcg_page_state_unit(int ite
switch (item) {
case MEMCG_PERCPU_B:
case MEMCG_ZSWAP_B:
+ case MEMCG_ZSWAP_WB:
case NR_SLAB_RECLAIMABLE_B:
case NR_SLAB_UNRECLAIMABLE_B:
return 1;
@@ -7899,6 +7901,19 @@ void obj_cgroup_uncharge_zswap(struct ob
rcu_read_unlock();
}
+void obj_cgroup_report_zswap_wb(struct obj_cgroup *objcg)
+{
+ struct mem_cgroup *memcg;
+
+ if (!cgroup_subsys_on_dfl(memory_cgrp_subsys))
+ return;
+
+ rcu_read_lock();
+ memcg = obj_cgroup_memcg(objcg);
+ mod_memcg_state(memcg, MEMCG_ZSWAP_WB, 1);
+ rcu_read_unlock();
+}
+
static u64 zswap_current_read(struct cgroup_subsys_state *css,
struct cftype *cft)
{
--- a/mm/zswap.c~mm-memcg-add-per-memcg-zswap-writeback-stat
+++ a/mm/zswap.c
@@ -704,6 +704,9 @@ static enum lru_status shrink_memcg_cb(s
}
zswap_written_back_pages++;
+ if (entry->objcg)
+ obj_cgroup_report_zswap_wb(entry->objcg);
+
/*
* Writeback started successfully, the page now belongs to the
* swapcache. Drop the entry from zswap - unless invalidate already
_
Patches currently in -mm which might be from cerasuolodomenico@xxxxxxxxx are
zswap-make-shrinking-memcg-aware.patch
mm-memcg-add-per-memcg-zswap-writeback-stat.patch
selftests-cgroup-update-per-memcg-zswap-writeback-selftest.patch
