From: SeongJae Park <sj@xxxxxxxxxx> Subject: mm/damon/reclaim: provide reclamation statistics This commit implements new DAMON_RECLAIM parameters for statistics reporting. Those can be used for understanding how DAMON_RECLAIM is working, and for tuning the other parameters. Link: https://lkml.kernel.org/r/20211210150016.35349-4-sj@xxxxxxxxxx Signed-off-by: SeongJae Park <sj@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/damon/reclaim.c | 46 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 46 insertions(+) --- a/mm/damon/reclaim.c~mm-damon-reclaim-provide-reclamation-statistics +++ a/mm/damon/reclaim.c @@ -185,6 +185,36 @@ module_param(monitor_region_end, ulong, static int kdamond_pid __read_mostly = -1; module_param(kdamond_pid, int, 0400); +/* + * Number of memory regions that tried to be reclaimed. + */ +static unsigned long nr_reclaim_tried_regions __read_mostly; +module_param(nr_reclaim_tried_regions, ulong, 0400); + +/* + * Total bytes of memory regions that tried to be reclaimed. + */ +static unsigned long bytes_reclaim_tried_regions __read_mostly; +module_param(bytes_reclaim_tried_regions, ulong, 0400); + +/* + * Number of memory regions that successfully be reclaimed. + */ +static unsigned long nr_reclaimed_regions __read_mostly; +module_param(nr_reclaimed_regions, ulong, 0400); + +/* + * Total bytes of memory regions that successfully be reclaimed. + */ +static unsigned long bytes_reclaimed_regions __read_mostly; +module_param(bytes_reclaimed_regions, ulong, 0400); + +/* + * Number of times that the time/space quota limits have exceeded + */ +static unsigned long nr_quota_exceeds __read_mostly; +module_param(nr_quota_exceeds, ulong, 0400); + static struct damon_ctx *ctx; static struct damon_target *target; @@ -333,6 +363,21 @@ static void damon_reclaim_timer_fn(struc } static DECLARE_DELAYED_WORK(damon_reclaim_timer, damon_reclaim_timer_fn); +static int damon_reclaim_after_aggregation(struct damon_ctx *c) +{ + struct damos *s; + + /* update the stats parameter */ + damon_for_each_scheme(s, c) { + nr_reclaim_tried_regions = s->stat.nr_tried; + bytes_reclaim_tried_regions = s->stat.sz_tried; + nr_reclaimed_regions = s->stat.nr_applied; + bytes_reclaimed_regions = s->stat.sz_applied; + nr_quota_exceeds = s->stat.qt_exceeds; + } + return 0; +} + static int __init damon_reclaim_init(void) { ctx = damon_new_ctx(); @@ -340,6 +385,7 @@ static int __init damon_reclaim_init(voi return -ENOMEM; damon_pa_set_primitives(ctx); + ctx->callback.after_aggregation = damon_reclaim_after_aggregation; /* 4242 means nothing but fun */ target = damon_new_target(4242); _