From: Yunjeong Mun <yunjeong.mun@sk.com>
Date: Mon, 7 Jul 2025 23:59:18 +0000 (+0900)
Subject: samples/damon: support automatic node address detection
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=749cc6533b662166fb387486e408e581a87b2a34;p=thirdparty%2Flinux.git

samples/damon: support automatic node address detection

This patch adds a new knob `detect_node_addresses`, which determines
whether the physical address range is set manually using the existing
knobs or automatically by the mtier module.  When `detect_node_addresses`
set to 'Y', mtier automatically converts node0 and node1 to their physical
addresses.  If set to 'N', it uses the existing 'node#_start_addr' and
'node#_end_addr' to define regions as before.

Link: https://lkml.kernel.org/r/20250707235919.513-1-yunjeong.mun@sk.com
Signed-off-by: Yunjeong Mun <yunjeong.mun@sk.com>
Suggested-by: Honggyu Kim <honggyu.kim@sk.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

diff --git a/samples/damon/mtier.c b/samples/damon/mtier.c
index 42e14df16f44a..7ebd352138e4f 100644
--- a/samples/damon/mtier.c
+++ b/samples/damon/mtier.c
@@ -47,8 +47,29 @@ static bool enabled __read_mostly;
 module_param_cb(enabled, &enabled_param_ops, &enabled, 0600);
 MODULE_PARM_DESC(enabled, "Enable or disable DAMON_SAMPLE_MTIER");
 
+static bool detect_node_addresses __read_mostly;
+module_param(detect_node_addresses, bool, 0600);
+
 static struct damon_ctx *ctxs[2];
 
+struct region_range {
+	phys_addr_t start;
+	phys_addr_t end;
+};
+
+static int nid_to_phys(int target_node, struct region_range *range)
+{
+	if (!node_online(target_node)) {
+		pr_err("NUMA node %d is not online\n", target_node);
+		return -EINVAL;
+	}
+
+	range->start = PFN_PHYS(node_start_pfn(target_node));
+	range->end  = PFN_PHYS(node_end_pfn(target_node));
+
+	return 0;
+}
+
 static struct damon_ctx *damon_sample_mtier_build_ctx(bool promote)
 {
 	struct damon_ctx *ctx;
@@ -58,6 +79,8 @@ static struct damon_ctx *damon_sample_mtier_build_ctx(bool promote)
 	struct damos *scheme;
 	struct damos_quota_goal *quota_goal;
 	struct damos_filter *filter;
+	struct region_range addr;
+	int ret;
 
 	ctx = damon_new_ctx();
 	if (!ctx)
@@ -87,9 +110,17 @@ static struct damon_ctx *damon_sample_mtier_build_ctx(bool promote)
 	if (!target)
 		goto free_out;
 	damon_add_target(ctx, target);
-	region = damon_new_region(
-			promote ? node1_start_addr : node0_start_addr,
-			promote ? node1_end_addr : node0_end_addr);
+
+	if (detect_node_addresses) {
+		ret = promote ? nid_to_phys(1, &addr) : nid_to_phys(0, &addr);
+		if (ret)
+			goto free_out;
+	} else {
+		addr.start = promote ? node1_start_addr : node0_start_addr;
+		addr.end = promote ? node1_end_addr : node0_end_addr;
+	}
+
+	region = damon_new_region(addr.start, addr.end);
 	if (!region)
 		goto free_out;
 	damon_add_region(region, target);