diff options
| author | Quanmin Yan <yanquanmin1@huawei.com> | 2025-09-10 19:32:21 +0800 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2025-09-21 14:22:33 -0700 |
| commit | 7db551fcfb2aa8a20740406d41b48fd4365fd17f (patch) | |
| tree | 373304f2e15002f0f0d5f3e32677ee4fc4e19976 | |
| parent | 2e0fe9245d6bcfc689961d58b43216adaece3182 (diff) | |
mm/damon/reclaim: support addr_unit for DAMON_RECLAIM
Implement a sysfs file to expose addr_unit for DAMON_RECLAIM users.
During parameter application, use the configured addr_unit parameter to
perform the necessary initialization. Similar to the core layer, prevent
setting addr_unit to zero.
It is worth noting that when monitor_region_start and monitor_region_end
are unset (i.e., 0), their values will later be set to biggest_system_ram.
At that point, addr_unit may not be the default value 1. Although we
could divide the biggest_system_ram value by addr_unit, changing addr_unit
without setting monitor_region_start/end should be considered a user
misoperation. And biggest_system_ram is only within the 0~ULONG_MAX
range, system can clearly work correctly with addr_unit=1. Therefore, if
monitor_region_start/end are unset, always silently reset addr_unit to 1.
Link: https://lkml.kernel.org/r/20250910113221.1065764-3-yanquanmin1@huawei.com
Signed-off-by: Quanmin Yan <yanquanmin1@huawei.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: ze zuo <zuoze1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | mm/damon/reclaim.c | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/mm/damon/reclaim.c b/mm/damon/reclaim.c index fb7c982a0018..590f9d6c55ef 100644 --- a/mm/damon/reclaim.c +++ b/mm/damon/reclaim.c @@ -129,6 +129,13 @@ static unsigned long monitor_region_end __read_mostly; module_param(monitor_region_end, ulong, 0600); /* + * Scale factor for DAMON_RECLAIM to ops address conversion. + * + * This parameter must not be set to 0. + */ +static unsigned long addr_unit __read_mostly = 1; + +/* * Skip anonymous pages reclamation. * * If this parameter is set as ``Y``, DAMON_RECLAIM does not reclaim anonymous @@ -194,6 +201,15 @@ static int damon_reclaim_apply_parameters(void) if (err) return err; + /* + * If monitor_region_start/end are unset, always silently + * reset addr_unit to 1. + */ + if (!monitor_region_start && !monitor_region_end) + addr_unit = 1; + param_ctx->addr_unit = addr_unit; + param_ctx->min_sz_region = max(DAMON_MIN_REGION / addr_unit, 1); + if (!damon_reclaim_mon_attrs.aggr_interval) { err = -EINVAL; goto out; @@ -294,6 +310,30 @@ static int damon_reclaim_turn(bool on) return damon_call(ctx, &call_control); } +static int damon_reclaim_addr_unit_store(const char *val, + const struct kernel_param *kp) +{ + unsigned long input_addr_unit; + int err = kstrtoul(val, 0, &input_addr_unit); + + if (err) + return err; + if (!input_addr_unit) + return -EINVAL; + + addr_unit = input_addr_unit; + return 0; +} + +static const struct kernel_param_ops addr_unit_param_ops = { + .set = damon_reclaim_addr_unit_store, + .get = param_get_ulong, +}; + +module_param_cb(addr_unit, &addr_unit_param_ops, &addr_unit, 0600); +MODULE_PARM_DESC(addr_unit, + "Scale factor for DAMON_RECLAIM to ops address conversion (default: 1)"); + static int damon_reclaim_enabled_store(const char *val, const struct kernel_param *kp) { |