[PATCH] mm/damon: simplify scheme create in lru_sort.c

From: Xin Hao
Date: Tue Sep 13 2022 - 13:11:40 EST


In damon_lru_sort_new_hot_scheme() and damon_lru_sort_new_cold_scheme(),
they have so much in common, so we can combine them into a single
function, and we just need to distinguish their differences.

Signed-off-by: Xin Hao <xhao@xxxxxxxxxxxxxxxxx>
---
mm/damon/lru_sort.c | 82 +++++++++++++++++----------------------------
1 file changed, 30 insertions(+), 52 deletions(-)

diff --git a/mm/damon/lru_sort.c b/mm/damon/lru_sort.c
index 8415e18fcf0e..62063ed43224 100644
--- a/mm/damon/lru_sort.c
+++ b/mm/damon/lru_sort.c
@@ -257,15 +257,15 @@ module_param(nr_cold_quota_exceeds, ulong, 0400);
static struct damon_ctx *ctx;
static struct damon_target *target;

-/* Create a DAMON-based operation scheme for hot memory regions */
-static struct damos *damon_lru_sort_new_hot_scheme(unsigned int hot_thres)
+static inline struct damos *damon_lru_sort_new_scheme(unsigned int thres,
+ enum damos_action action)
{
struct damos_access_pattern pattern = {
/* Find regions having PAGE_SIZE or larger size */
.min_sz_region = PAGE_SIZE,
.max_sz_region = ULONG_MAX,
/* and accessed for more than the threshold */
- .min_nr_accesses = hot_thres,
+ .min_nr_accesses = 0,
.max_nr_accesses = UINT_MAX,
/* no matter its age */
.min_age_region = 0,
@@ -292,60 +292,38 @@ static struct damos *damon_lru_sort_new_hot_scheme(unsigned int hot_thres)
.weight_age = 0,
};

- return damon_new_scheme(
- &pattern,
- /* prioritize those on LRU lists, as soon as found */
- DAMOS_LRU_PRIO,
- /* under the quota. */
- &quota,
- /* (De)activate this according to the watermarks. */
- &wmarks);
+ switch (action) {
+ case DAMOS_LRU_PRIO:
+ pattern.min_nr_accesses = thres;
+ break;
+ case DAMOS_LRU_DEPRIO:
+ pattern.min_age_region = thres;
+ quota.weight_nr_accesses = 0;
+ quota.weight_age = 1;
+ break;
+ default:
+ return NULL;
+ }
+
+ return damon_new_scheme(&pattern,
+ /* mark those as not accessed, as soon as found */
+ action,
+ /* under the quota. */
+ &quota,
+ /* (De)activate this according to the watermarks. */
+ &wmarks);
+}
+
+/* Create a DAMON-based operation scheme for hot memory regions */
+static struct damos *damon_lru_sort_new_hot_scheme(unsigned int hot_thres)
+{
+ return damon_lru_sort_new_scheme(hot_thres, DAMOS_LRU_PRIO);
}

/* Create a DAMON-based operation scheme for cold memory regions */
static struct damos *damon_lru_sort_new_cold_scheme(unsigned int cold_thres)
{
- struct damos_access_pattern pattern = {
- /* Find regions having PAGE_SIZE or larger size */
- .min_sz_region = PAGE_SIZE,
- .max_sz_region = ULONG_MAX,
- /* and not accessed at all */
- .min_nr_accesses = 0,
- .max_nr_accesses = 0,
- /* for min_age or more micro-seconds */
- .min_age_region = cold_thres,
- .max_age_region = UINT_MAX,
- };
- struct damos_watermarks wmarks = {
- .metric = DAMOS_WMARK_FREE_MEM_RATE,
- .interval = wmarks_interval,
- .high = wmarks_high,
- .mid = wmarks_mid,
- .low = wmarks_low,
- };
- struct damos_quota quota = {
- /*
- * Do not try LRU-lists sorting of cold pages for more than
- * half of quota_ms milliseconds within
- * quota_reset_interval_ms.
- */
- .ms = quota_ms / 2,
- .sz = 0,
- .reset_interval = quota_reset_interval_ms,
- /* Within the quota, mark colder regions not accessed first. */
- .weight_sz = 0,
- .weight_nr_accesses = 0,
- .weight_age = 1,
- };
-
- return damon_new_scheme(
- &pattern,
- /* mark those as not accessed, as soon as found */
- DAMOS_LRU_DEPRIO,
- /* under the quota. */
- &quota,
- /* (De)activate this according to the watermarks. */
- &wmarks);
+ return damon_lru_sort_new_scheme(cold_thres, DAMOS_LRU_DEPRIO);
}

static int damon_lru_sort_apply_parameters(void)
--
2.31.0