[RFC PATCH 01/18] mm/damon/modules: deduplicate init steps for DAMON context setup

From: SeongJae Park
Date: Tue Oct 18 2022 - 20:13:46 EST


DAMON_RECLAIM and DAMON_LRU_SORT has duplicated code for DAMON context
and target initializations. Deduplicate the part by implementing a
function for the initialization in 'modules-common.c' and using it.

Signed-off-by: SeongJae Park <sj@xxxxxxxxxx>
---
mm/damon/Makefile | 4 ++--
mm/damon/lru_sort.c | 17 +++-------------
mm/damon/modules-common.c | 42 +++++++++++++++++++++++++++++++++++++++
mm/damon/modules-common.h | 3 +++
mm/damon/reclaim.c | 17 +++-------------
5 files changed, 53 insertions(+), 30 deletions(-)
create mode 100644 mm/damon/modules-common.c

diff --git a/mm/damon/Makefile b/mm/damon/Makefile
index 3e6b8ad73858..a076ccd55d44 100644
--- a/mm/damon/Makefile
+++ b/mm/damon/Makefile
@@ -5,5 +5,5 @@ obj-$(CONFIG_DAMON_VADDR) += ops-common.o vaddr.o
obj-$(CONFIG_DAMON_PADDR) += ops-common.o paddr.o
obj-$(CONFIG_DAMON_SYSFS) += sysfs.o
obj-$(CONFIG_DAMON_DBGFS) += dbgfs.o
-obj-$(CONFIG_DAMON_RECLAIM) += reclaim.o
-obj-$(CONFIG_DAMON_LRU_SORT) += lru_sort.o
+obj-$(CONFIG_DAMON_RECLAIM) += modules-common.o reclaim.o
+obj-$(CONFIG_DAMON_LRU_SORT) += modules-common.o lru_sort.o
diff --git a/mm/damon/lru_sort.c b/mm/damon/lru_sort.c
index efbc2bda8b9c..a1896c5acfe9 100644
--- a/mm/damon/lru_sort.c
+++ b/mm/damon/lru_sort.c
@@ -314,25 +314,14 @@ static int damon_lru_sort_after_wmarks_check(struct damon_ctx *c)

static int __init damon_lru_sort_init(void)
{
- ctx = damon_new_ctx();
- if (!ctx)
- return -ENOMEM;
+ int err = damon_modules_new_paddr_ctx_target(&ctx, &target);

- if (damon_select_ops(ctx, DAMON_OPS_PADDR)) {
- damon_destroy_ctx(ctx);
- return -EINVAL;
- }
+ if (err)
+ return err;

ctx->callback.after_wmarks_check = damon_lru_sort_after_wmarks_check;
ctx->callback.after_aggregation = damon_lru_sort_after_aggregation;

- target = damon_new_target();
- if (!target) {
- damon_destroy_ctx(ctx);
- return -ENOMEM;
- }
- damon_add_target(ctx, target);
-
schedule_delayed_work(&damon_lru_sort_timer, 0);

damon_lru_sort_initialized = true;
diff --git a/mm/damon/modules-common.c b/mm/damon/modules-common.c
new file mode 100644
index 000000000000..b2381a8466ec
--- /dev/null
+++ b/mm/damon/modules-common.c
@@ -0,0 +1,42 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Common Primitives for DAMON Modules
+ *
+ * Author: SeongJae Park <sjpark@xxxxxxxxx>
+ */
+
+#include <linux/damon.h>
+
+#include "modules-common.h"
+
+/*
+ * Allocate, set, and return a DAMON context for the physical address space.
+ * @ctxp: Pointer to save the point to the newly created context
+ * @targetp: Pointer to save the point to the newly created target
+ */
+int damon_modules_new_paddr_ctx_target(struct damon_ctx **ctxp,
+ struct damon_target **targetp)
+{
+ struct damon_ctx *ctx;
+ struct damon_target *target;
+
+ ctx = damon_new_ctx();
+ if (!ctx)
+ return -ENOMEM;
+
+ if (damon_select_ops(ctx, DAMON_OPS_PADDR)) {
+ damon_destroy_ctx(ctx);
+ return -EINVAL;
+ }
+
+ target = damon_new_target();
+ if (!target) {
+ damon_destroy_ctx(ctx);
+ return -ENOMEM;
+ }
+ damon_add_target(ctx, target);
+
+ *ctxp = ctx;
+ *targetp = target;
+ return 0;
+}
diff --git a/mm/damon/modules-common.h b/mm/damon/modules-common.h
index 5a4921851d32..f49cdb417005 100644
--- a/mm/damon/modules-common.h
+++ b/mm/damon/modules-common.h
@@ -44,3 +44,6 @@
0400); \
module_param_named(nr_##qt_exceed_name, stat.qt_exceeds, ulong, \
0400);
+
+int damon_modules_new_paddr_ctx_target(struct damon_ctx **ctxp,
+ struct damon_target **targetp);
diff --git a/mm/damon/reclaim.c b/mm/damon/reclaim.c
index 162c9b1ca00f..3173f373435c 100644
--- a/mm/damon/reclaim.c
+++ b/mm/damon/reclaim.c
@@ -256,25 +256,14 @@ static int damon_reclaim_after_wmarks_check(struct damon_ctx *c)

static int __init damon_reclaim_init(void)
{
- ctx = damon_new_ctx();
- if (!ctx)
- return -ENOMEM;
+ int err = damon_modules_new_paddr_ctx_target(&ctx, &target);

- if (damon_select_ops(ctx, DAMON_OPS_PADDR)) {
- damon_destroy_ctx(ctx);
- return -EINVAL;
- }
+ if (err)
+ return err;

ctx->callback.after_wmarks_check = damon_reclaim_after_wmarks_check;
ctx->callback.after_aggregation = damon_reclaim_after_aggregation;

- target = damon_new_target();
- if (!target) {
- damon_destroy_ctx(ctx);
- return -ENOMEM;
- }
- damon_add_target(ctx, target);
-
schedule_delayed_work(&damon_reclaim_timer, 0);

damon_reclaim_initialized = true;
--
2.25.1