From: SeongJae Park <[email protected]>
DAMON_RECLAIM reads the user input parameters only when it starts. To
allow more efficient online tuning, this commit implements a new input
parameter called 'commit_inputs'. Writing true to the parameter makes
DAMON_RECLAIM reads the input parameters again.
Signed-off-by: SeongJae Park <[email protected]>
---
mm/damon/reclaim.c | 95 ++++++++++++++++++++++++++++++----------------
1 file changed, 62 insertions(+), 33 deletions(-)
diff --git a/mm/damon/reclaim.c b/mm/damon/reclaim.c
index 75cfd96a6060..f37c5d4b27fa 100644
--- a/mm/damon/reclaim.c
+++ b/mm/damon/reclaim.c
@@ -29,6 +29,18 @@
*/
static bool enabled __read_mostly;
+/*
+ * Make DAMON_RECLAIM reads the input parameters again, except ``enabled``.
+ *
+ * Input parameters that updated while DAMON_RECLAIM is running are not applied
+ * by default. Once this parameter is set as ``Y``, DAMON_RECLAIM reads values
+ * of parametrs except ``enabled`` again. Once the re-reading is done, this
+ * parameter is set as ``N``. If invalid parameters are found while the
+ * re-reading, DAMON_RECLAIM will be disabled.
+ */
+static bool commit_inputs __read_mostly;
+module_param(commit_inputs, bool, 0600);
+
/*
* Time threshold for cold memory regions identification in microseconds.
*
@@ -289,57 +301,56 @@ static struct damos *damon_reclaim_new_scheme(void)
return scheme;
}
-static int damon_reclaim_turn(bool on)
+static int damon_reclaim_apply_parameters(void)
{
- struct damon_region *region;
struct damos *scheme;
- int err;
-
- if (!on) {
- err = damon_stop(&ctx, 1);
- if (!err)
- kdamond_pid = -1;
- return err;
- }
+ struct damon_addr_range addr_range;
+ int err = 0;
err = damon_set_attrs(ctx, sample_interval, aggr_interval, 0,
min_nr_regions, max_nr_regions);
if (err)
return err;
+ /* Will be freed by next 'damon_set_schemes()' below */
+ scheme = damon_reclaim_new_scheme();
+ if (!scheme)
+ return -ENOMEM;
+ err = damon_set_schemes(ctx, &scheme, 1);
+ if (err)
+ return err;
+
if (monitor_region_start > monitor_region_end)
return -EINVAL;
if (!monitor_region_start && !monitor_region_end &&
!get_monitoring_region(&monitor_region_start,
&monitor_region_end))
return -EINVAL;
- /* DAMON will free this on its own when finish monitoring */
- region = damon_new_region(monitor_region_start, monitor_region_end);
- if (!region)
- return -ENOMEM;
- damon_add_region(region, target);
+ addr_range.start = monitor_region_start;
+ addr_range.end = monitor_region_end;
+ return damon_set_regions(target, &addr_range, 1);
+}
- /* Will be freed by 'damon_set_schemes()' below */
- scheme = damon_reclaim_new_scheme();
- if (!scheme) {
- err = -ENOMEM;
- goto free_region_out;
+static int damon_reclaim_turn(bool on)
+{
+ int err;
+
+ if (!on) {
+ err = damon_stop(&ctx, 1);
+ if (!err)
+ kdamond_pid = -1;
+ return err;
}
- err = damon_set_schemes(ctx, &scheme, 1);
+
+ err = damon_reclaim_apply_parameters();
if (err)
- goto free_scheme_out;
+ return err;
err = damon_start(&ctx, 1, true);
- if (!err) {
- kdamond_pid = ctx->kdamond->pid;
- return 0;
- }
-
-free_scheme_out:
- damon_destroy_scheme(scheme);
-free_region_out:
- damon_destroy_region(region, target);
- return err;
+ if (err)
+ return err;
+ kdamond_pid = ctx->kdamond->pid;
+ return 0;
}
#define ENABLE_CHECK_INTERVAL_MS 1000
@@ -389,6 +400,7 @@ MODULE_PARM_DESC(enabled,
static int damon_reclaim_after_aggregation(struct damon_ctx *c)
{
struct damos *s;
+ int err = 0;
/* update the stats parameter */
damon_for_each_scheme(s, c) {
@@ -398,7 +410,23 @@ static int damon_reclaim_after_aggregation(struct damon_ctx *c)
bytes_reclaimed_regions = s->stat.sz_applied;
nr_quota_exceeds = s->stat.qt_exceeds;
}
- return 0;
+
+ if (commit_inputs) {
+ err = damon_reclaim_apply_parameters();
+ commit_inputs = false;
+ }
+ return err;
+}
+
+static int damon_reclaim_after_wmarks_check(struct damon_ctx *c)
+{
+ int err = 0;
+
+ if (commit_inputs) {
+ err = damon_reclaim_apply_parameters();
+ commit_inputs = false;
+ }
+ return err;
}
static int __init damon_reclaim_init(void)
@@ -410,6 +438,7 @@ static int __init damon_reclaim_init(void)
if (damon_select_ops(ctx, DAMON_OPS_PADDR))
return -EINVAL;
+ ctx->callback.after_wmarks_check = damon_reclaim_after_wmarks_check;
ctx->callback.after_aggregation = damon_reclaim_after_aggregation;
target = damon_new_target();
--
2.25.1