[RFC PATCH v2 02/11] mm/damon/paddr: support DAMOS filters

SeongJae Park
2022-11-30T20:09:54Z

Implement support of the DAMOS filters in the physical address space
monitoring operations set, for all DAMOS actions that it supports
including 'pageout', 'lru_prio', and 'lru_deprio'.

Signed-off-by: SeongJae Park <sj@kernel.org>
---
mm/damon/paddr.c | 71 ++++++++++++++++++++++++++++++++++++++++++------
1 file changed, 62 insertions(+), 9 deletions(-)

diff --git a/mm/damon/paddr.c b/mm/damon/paddr.c
index e1a4315c4be6..ebd1905eed6f 100644
--- a/mm/damon/paddr.c
+++ b/mm/damon/paddr.c
@@ -202,7 +202,47 @@ static unsigned int damon_pa_check_accesses(struct damon_ctx *ctx)
return max_nr_accesses;
}

-static unsigned long damon_pa_pageout(struct damon_region *r)
+static bool __damos_pa_filter_out(struct damos_filter *filter,
+ struct page *page)
+{
+ bool matched = false;
+ struct mem_cgroup *memcg;
+
+ switch (filter->type) {
+ case DAMOS_FILTER_TYPE_ANON:
+ matched = PageAnon(page);
+ break;
+ case DAMOS_FILTER_TYPE_MEMCG:
+ rcu_read_lock();
+ memcg = page_memcg_check(page);
+ if (!memcg)
+ matched = false;
+ else
+ matched = filter->memcg_id == mem_cgroup_id(memcg);
+ rcu_read_unlock();
+ break;
+ default:
+ break;
+ }
+
+ return matched == filter->matching;
+}
+
+/*
+ * damos_pa_filter_out - Return true if the page should be filtered out.
+ */
+static bool damos_pa_filter_out(struct damos *scheme, struct page *page)
+{
+ struct damos_filter *filter;
+
+ damos_for_each_filter(filter, scheme) {
+ if (__damos_pa_filter_out(filter, page))
+ return true;
+ }
+ return false;
+}
+
+static unsigned long damon_pa_pageout(struct damon_region *r, struct damos *s)
{
unsigned long addr, applied;
LIST_HEAD(page_list);
@@ -213,6 +253,11 @@ static unsigned long damon_pa_pageout(struct damon_region *r)
if (!page)
continue;

+ if (damos_pa_filter_out(s, page)) {
+ put_page(page);
+ continue;
+ }
+
ClearPageReferenced(page);
test_and_clear_page_young(page);
if (isolate_lru_page(page)) {
@@ -232,7 +277,7 @@ static unsigned long damon_pa_pageout(struct damon_region *r)
}

static inline unsigned long damon_pa_mark_accessed_or_deactivate(
- struct damon_region *r, bool mark_accessed)
+ struct damon_region *r, struct damos *s, bool mark_accessed)
{
unsigned long addr, applied = 0;

@@ -241,6 +286,12 @@ static inline unsigned long damon_pa_mark_accessed_or_deactivate(

if (!page)
continue;
+
+ if (damos_pa_filter_out(s, page)) {
+ put_page(page);
+ continue;
+ }
+
if (mark_accessed)
mark_page_accessed(page);
else
@@ -251,14 +302,16 @@ static inline unsigned long damon_pa_mark_accessed_or_deactivate(
return applied * PAGE_SIZE;
}

-static unsigned long damon_pa_mark_accessed(struct damon_region *r)
+static unsigned long damon_pa_mark_accessed(struct damon_region *r,
+ struct damos *s)
{
- return damon_pa_mark_accessed_or_deactivate(r, true);
+ return damon_pa_mark_accessed_or_deactivate(r, s, true);
}

-static unsigned long damon_pa_deactivate_pages(struct damon_region *r)
+static unsigned long damon_pa_deactivate_pages(struct damon_region *r,
+ struct damos *s)
{
- return damon_pa_mark_accessed_or_deactivate(r, false);
+ return damon_pa_mark_accessed_or_deactivate(r, s, false);
}

static unsigned long damon_pa_apply_scheme(struct damon_ctx *ctx,
@@ -267,11 +320,11 @@ static unsigned long damon_pa_apply_scheme(struct damon_ctx *ctx,
{
switch (scheme->action) {
case DAMOS_PAGEOUT:
- return damon_pa_pageout(r);
+ return damon_pa_pageout(r, scheme);
case DAMOS_LRU_PRIO:
- return damon_pa_mark_accessed(r);
+ return damon_pa_mark_accessed(r, scheme);
case DAMOS_LRU_DEPRIO:
- return damon_pa_deactivate_pages(r);
+ return damon_pa_deactivate_pages(r, scheme);
case DAMOS_STAT:
break;
default:
--
2.25.1