This patch add swappiness arg into proactive reclaim interface.
User can type "bytes swappiness" into memory.reclaim to control
reclaim tendency.
Specially, user can type below to only reclaim anon folios:
`"100M" 200 > memory.reclaim`
Or, type below to only reclaim file folios:
`100M 1 > memory.reclaim`
User can only type key into memory.reclaim to keep original use.
Signed-off-by: Huan Yang <link@xxxxxxxx>
---
Documentation/admin-guide/cgroup-v2.rst | 16 ++++---
include/linux/swap.h | 2 +
mm/memcontrol.c | 55 +++++++++++++++++++++----
mm/vmscan.c | 2 +
4 files changed, 63 insertions(+), 12 deletions(-)
diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst
index c153d0c75f34..5a471ac7f0c3 100644
--- a/Documentation/admin-guide/cgroup-v2.rst
+++ b/Documentation/admin-guide/cgroup-v2.rst
@@ -1275,16 +1275,22 @@ PAGE_SIZE multiple when read back.
This is a simple interface to trigger memory reclaim in the
target cgroup.
- This file accepts a single key, the number of bytes to reclaim.
- No nested keys are currently supported.
+ This file accepts a few key, the number of bytes to reclaim.
+ Few nested keys are currently supported.
Example::
echo "1G" > memory.reclaim
- The interface can be later extended with nested keys to
- configure the reclaim behavior. For example, specify the
- type of memory to reclaim from (anon, file, ..).
+ The interface extended with nested keys to configure the
+ reclaim behavior. For example, specify the swappiness of
+ memory to reclaim from (anon, file, ..).
+
+ Example::
+
+ echo "1G" 200 > memory.reclaim (only reclaim anon)
+ echo "1G" 0 > memory.reclaim (only reclaim file)
+ echo "1G" 1 > memory.reclaim (only reclaim file)
Please note that the kernel can over or under reclaim from
the target cgroup. If less bytes are reclaimed than the
diff --git a/include/linux/swap.h b/include/linux/swap.h
index 3ba146ae7cf5..a024194301d4 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -407,6 +407,8 @@ extern unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
#define MEMCG_RECLAIM_MAY_SWAP (1 << 1)
#define MEMCG_RECLAIM_PROACTIVE (1 << 2)
+#define MEMCG_RECLAIM_ANON (1 << 3)
+#define MEMCG_RECLAIM_FILE (1 << 4)
extern unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg,
unsigned long nr_pages,
gfp_t gfp_mask,
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index be2ad117515e..a0e460abd41c 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -6953,19 +6953,47 @@ static ssize_t memory_reclaim(struct kernfs_open_file *of, char *buf,
unsigned int nr_retries = MAX_RECLAIM_RETRIES;
unsigned long nr_to_reclaim, nr_reclaimed = 0;
unsigned int reclaim_options;
+ int swappiness = -1, org_swappiness, n;
+ char *tmpbuf;
int err;
- buf = strstrip(buf);
- err = page_counter_memparse(buf, "", &nr_to_reclaim);
+ tmpbuf = kvzalloc(nbytes, GFP_KERNEL);
+ if (unlikely(!tmpbuf))
+ return -ENOMEM;
+
+ buf = skip_spaces(buf);
+ n = sscanf(buf, "%s %d", tmpbuf, &swappiness);
+ if (n < 1) {
+ err = -EINVAL;
+ goto out_free;
+ }
+
+ if (n == 2 && (swappiness > 200 || swappiness < 0)) {
+ err = -EINVAL;
+ goto out_free;
+ }
+
+ err = page_counter_memparse(tmpbuf, "", &nr_to_reclaim);
if (err)
- return err;
+ goto out_free;
reclaim_options = MEMCG_RECLAIM_MAY_SWAP | MEMCG_RECLAIM_PROACTIVE;
+ if (swappiness != -1) {
+ org_swappiness = memcg->swappiness;
+ memcg->swappiness = swappiness;
+ if (swappiness == 200)
+ reclaim_options |= MEMCG_RECLAIM_ANON;
+ else if (swappiness == 0 || swappiness == 1)
+ reclaim_options |= MEMCG_RECLAIM_FILE;
+ }
+
while (nr_reclaimed < nr_to_reclaim) {
unsigned long reclaimed;
- if (signal_pending(current))
- return -EINTR;
+ if (signal_pending(current)) {
+ err = -EINTR;
+ goto out;
+ }
/*
* This is the final attempt, drain percpu lru caches in the
@@ -6979,13 +7007,26 @@ static ssize_t memory_reclaim(struct kernfs_open_file *of, char *buf,
min(nr_to_reclaim - nr_reclaimed, SWAP_CLUSTER_MAX),
GFP_KERNEL, reclaim_options);
- if (!reclaimed && !nr_retries--)
- return -EAGAIN;
+ if (!reclaimed && !nr_retries--) {
+ err = -EAGAIN;
+ goto out;
+ }
nr_reclaimed += reclaimed;
}
+ if (swappiness != -1)
+ memcg->swappiness = org_swappiness;
+
return nbytes;
+
+out:
+ if (swappiness != -1)
+ memcg->swappiness = org_swappiness;
+
+out_free:
+ kvfree(tmpbuf);
+ return err;
}
static struct cftype memory_files[] = {
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 9243a1f0d606..f4221ec833db 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -6505,6 +6505,8 @@ unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg,
.may_unmap = 1,
.may_swap = !!(reclaim_options & MEMCG_RECLAIM_MAY_SWAP),
.proactive = !!(reclaim_options & MEMCG_RECLAIM_PROACTIVE),
+ .unbalance_anon = !!(reclaim_options & MEMCG_RECLAIM_ANON),
+ .unbalance_file = !!(reclaim_options & MEMCG_RECLAIM_FILE),
};
/*
* Traverse the ZONELIST_FALLBACK zonelist of the current node to put
--
2.34.1
