From b757c6cfc696d43501632861f731412b14a7be86 Mon Sep 17 00:00:00 2001 From: SeongJae Park Date: Tue, 10 Dec 2024 13:50:27 -0800 Subject: [PATCH] samples/damon/wsse: start and stop DAMON as the user requests 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. Link: https://lkml.kernel.org/r/20241210215030.85675-3-sj@kernel.org Signed-off-by: SeongJae Park Signed-off-by: Andrew Morton --- samples/damon/wsse.c | 35 ++++++++++++++++++++++++++++++++++- 1 file changed, 34 insertions(+), 1 deletion(-) 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( -- 2.25.1