2022-09-20 17:35:34

by SeongJae Park

[permalink] [raw]
Subject: [PATCH v3] mm/damon: deduplicate damon_{reclaim,lru_sort}_apply_parameters()

From: [email protected]

From: Kaixu Xia <[email protected]>

The bodies of damon_{reclaim,lru_sort}_apply_parameters() contain
duplicates. This commit adds a common function
damon_set_region_biggest_system_ram_default() to remove the
duplicates.

Signed-off-by: Kaixu Xia <[email protected]>
Suggested-by: SeongJae Park <[email protected]>
Reviewed-by: SeongJae Park <[email protected]>
Signed-off-by: SeongJae Park <[email protected]>
---
Patch changelog

from v2
(https://lore.kernel.org/damon/[email protected]/):
- fix some trivial grammar mistakes
- add links to previous versions
from v1
(https://lore.kernel.org/damon/[email protected]/):
- change the common function name and add kernel comment.

include/linux/damon.h | 3 ++-
mm/damon/core.c | 35 ++++++++++++++++++++++++++++++++++-
mm/damon/lru_sort.c | 13 +++----------
mm/damon/reclaim.c | 13 +++----------
4 files changed, 42 insertions(+), 22 deletions(-)

diff --git a/include/linux/damon.h b/include/linux/damon.h
index e7808a84675f..ed5470f50bab 100644
--- a/include/linux/damon.h
+++ b/include/linux/damon.h
@@ -557,7 +557,8 @@ static inline bool damon_target_has_pid(const struct damon_ctx *ctx)
int damon_start(struct damon_ctx **ctxs, int nr_ctxs, bool exclusive);
int damon_stop(struct damon_ctx **ctxs, int nr_ctxs);

-bool damon_find_biggest_system_ram(unsigned long *start, unsigned long *end);
+int damon_set_region_biggest_system_ram_default(struct damon_target *t,
+ unsigned long *start, unsigned long *end);

#endif /* CONFIG_DAMON */

diff --git a/mm/damon/core.c b/mm/damon/core.c
index 9c80c6eb00c2..9e96cb9fb5db 100644
--- a/mm/damon/core.c
+++ b/mm/damon/core.c
@@ -1245,7 +1245,8 @@ static int walk_system_ram(struct resource *res, void *arg)
* Find biggest 'System RAM' resource and store its start and end address in
* @start and @end, respectively. If no System RAM is found, returns false.
*/
-bool damon_find_biggest_system_ram(unsigned long *start, unsigned long *end)
+static bool damon_find_biggest_system_ram(unsigned long *start,
+ unsigned long *end)

{
struct damon_system_ram_region arg = {};
@@ -1259,6 +1260,38 @@ bool damon_find_biggest_system_ram(unsigned long *start, unsigned long *end)
return true;
}

+/**
+ * damon_set_region_biggest_system_ram_default() - Set the region of the given
+ * monitoring target as requested, or biggest 'System RAM'.
+ * @t: The monitoring target to set the region.
+ * @start: The pointer to the start address of the region.
+ * @end: The pointer to the end address of the region.
+ *
+ * This function sets the region of @t as requested by @start and @end. If the
+ * values of @start and @end are zero, however, this function finds the biggest
+ * 'System RAM' resource and sets the region to cover the resource. In the
+ * latter case, this function saves the start and end addresses of the resource
+ * in @start and @end, respectively.
+ *
+ * Return: 0 on success, negative error code otherwise.
+ */
+int damon_set_region_biggest_system_ram_default(struct damon_target *t,
+ unsigned long *start, unsigned long *end)
+{
+ struct damon_addr_range addr_range;
+
+ if (*start > *end)
+ return -EINVAL;
+
+ if (!*start && !*end &&
+ !damon_find_biggest_system_ram(start, end))
+ return -EINVAL;
+
+ addr_range.start = *start;
+ addr_range.end = *end;
+ return damon_set_regions(t, &addr_range, 1);
+}
+
static int __init damon_init(void)
{
damon_region_cache = KMEM_CACHE(damon_region, 0);
diff --git a/mm/damon/lru_sort.c b/mm/damon/lru_sort.c
index d7eb72b41cb6..efbc2bda8b9c 100644
--- a/mm/damon/lru_sort.c
+++ b/mm/damon/lru_sort.c
@@ -188,7 +188,6 @@ static struct damos *damon_lru_sort_new_cold_scheme(unsigned int cold_thres)
static int damon_lru_sort_apply_parameters(void)
{
struct damos *scheme;
- struct damon_addr_range addr_range;
unsigned int hot_thres, cold_thres;
int err = 0;

@@ -211,15 +210,9 @@ static int damon_lru_sort_apply_parameters(void)
return -ENOMEM;
damon_add_scheme(ctx, scheme);

- if (monitor_region_start > monitor_region_end)
- return -EINVAL;
- if (!monitor_region_start && !monitor_region_end &&
- !damon_find_biggest_system_ram(&monitor_region_start,
- &monitor_region_end))
- return -EINVAL;
- addr_range.start = monitor_region_start;
- addr_range.end = monitor_region_end;
- return damon_set_regions(target, &addr_range, 1);
+ return damon_set_region_biggest_system_ram_default(target,
+ &monitor_region_start,
+ &monitor_region_end);
}

static int damon_lru_sort_turn(bool on)
diff --git a/mm/damon/reclaim.c b/mm/damon/reclaim.c
index 3d59ab11b7b3..162c9b1ca00f 100644
--- a/mm/damon/reclaim.c
+++ b/mm/damon/reclaim.c
@@ -144,7 +144,6 @@ static struct damos *damon_reclaim_new_scheme(void)
static int damon_reclaim_apply_parameters(void)
{
struct damos *scheme;
- struct damon_addr_range addr_range;
int err = 0;

err = damon_set_attrs(ctx, &damon_reclaim_mon_attrs);
@@ -157,15 +156,9 @@ static int damon_reclaim_apply_parameters(void)
return -ENOMEM;
damon_set_schemes(ctx, &scheme, 1);

- if (monitor_region_start > monitor_region_end)
- return -EINVAL;
- if (!monitor_region_start && !monitor_region_end &&
- !damon_find_biggest_system_ram(&monitor_region_start,
- &monitor_region_end))
- return -EINVAL;
- addr_range.start = monitor_region_start;
- addr_range.end = monitor_region_end;
- return damon_set_regions(target, &addr_range, 1);
+ return damon_set_region_biggest_system_ram_default(target,
+ &monitor_region_start,
+ &monitor_region_end);
}

static int damon_reclaim_turn(bool on)
--
2.27.0