diff mbox series

[2/5] samples/damon/wsse: start and stop DAMON as the user requests

Message ID 20241210215030.85675-3-sj@kernel.org (mailing list archive)
State New
Headers show
Series mm/damon: add sample modules | expand

Commit Message

SeongJae Park Dec. 10, 2024, 9:50 p.m. UTC
Start running DAMON to monitor accesses of a process that the user
specified via 'target_pid' parameter, when 'y' is passed to 'enable'
parameter.  Stop running DAMON when 'n' is passed to 'enable' parameter.
Estimating the working set size from DAMON's monitoring results and
reporting it to the user will be implemented by the following commit.

Signed-off-by: SeongJae Park <sj@kernel.org>
---
 samples/damon/wsse.c | 35 ++++++++++++++++++++++++++++++++++-
 1 file changed, 34 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/samples/damon/wsse.c b/samples/damon/wsse.c
index 7f2cb76a1a70..2ba0c91baad9 100644
--- a/samples/damon/wsse.c
+++ b/samples/damon/wsse.c
@@ -27,15 +27,48 @@  static bool enable __read_mostly;
 module_param_cb(enable, &enable_param_ops, &enable, 0600);
 MODULE_PARM_DESC(enable, "Enable or disable DAMON_SAMPLE_WSSE");
 
+static struct damon_ctx *ctx;
+static struct pid *target_pidp;
+
 static int damon_sample_wsse_start(void)
 {
+	struct damon_target *target;
+
 	pr_info("start\n");
-	return 0;
+
+	ctx = damon_new_ctx();
+	if (!ctx)
+		return -ENOMEM;
+	if (damon_select_ops(ctx, DAMON_OPS_VADDR)) {
+		damon_destroy_ctx(ctx);
+		return -EINVAL;
+	}
+
+	target = damon_new_target();
+	if (!target) {
+		damon_destroy_ctx(ctx);
+		return -ENOMEM;
+	}
+	damon_add_target(ctx, target);
+	target_pidp = find_get_pid(target_pid);
+	if (!target_pidp) {
+		damon_destroy_ctx(ctx);
+		return -EINVAL;
+	}
+	target->pid = target_pidp;
+
+	return damon_start(&ctx, 1, true);
 }
 
 static void damon_sample_wsse_stop(void)
 {
 	pr_info("stop\n");
+	if (ctx) {
+		damon_stop(&ctx, 1);
+		damon_destroy_ctx(ctx);
+	}
+	if (target_pidp)
+		put_pid(target_pidp);
 }
 
 static int damon_sample_wsse_enable_store(