The patch titled Subject: mm/damon/reclaim: fix quota stauts loss due to online tunings has been added to the -mm mm-hotfixes-unstable branch. Its filename is mm-damon-reclaim-fix-quota-stauts-loss-due-to-online-tunings.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-damon-reclaim-fix-quota-stauts-loss-due-to-online-tunings.patch This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: SeongJae Park <sj@xxxxxxxxxx> Subject: mm/damon/reclaim: fix quota stauts loss due to online tunings Date: Fri, 16 Feb 2024 11:40:24 -0800 Patch series "mm/damon: fix quota status loss due to online tunings". DAMON_RECLAIM and DAMON_LRU_SORT is not preserving internal quota status when applying new user parameters, and hence could cause temporal quota accuracy degradation. Fix it by preserving the status. This patch (of 2): For online parameters change, DAMON_RECLAIM creates new scheme based on latest values of the parameters and replaces the old scheme with the new one. When creating it, the internal status of the quota of the old scheme is not preserved. As a result, charging of the quota starts from zero after the online tuning. The data that collected to estimate the throughput of the scheme's action is also reset, and therefore the estimation should start from the scratch again. Because the throughput estimation is being used to convert the time quota to the effective size quota, this could result in temporal time quota inaccuracy. It would be recovered over time, though. In short, the quota accuracy could be temporarily degraded after online parameters update. Fix the problem by checking the case and copying the internal fields for the status. Link: https://lkml.kernel.org/r/20240216194025.9207-1-sj@xxxxxxxxxx Link: https://lkml.kernel.org/r/20240216194025.9207-2-sj@xxxxxxxxxx Fixes: e035c280f6df ("mm/damon/reclaim: support online inputs update") Signed-off-by: SeongJae Park <sj@xxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> [5.19+] Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/damon/reclaim.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) --- a/mm/damon/reclaim.c~mm-damon-reclaim-fix-quota-stauts-loss-due-to-online-tunings +++ a/mm/damon/reclaim.c @@ -150,9 +150,20 @@ static struct damos *damon_reclaim_new_s &damon_reclaim_wmarks); } +static void damon_reclaim_copy_quota_status(struct damos_quota *dst, + struct damos_quota *src) +{ + dst->total_charged_sz = src->total_charged_sz; + dst->total_charged_ns = src->total_charged_ns; + dst->charged_sz = src->charged_sz; + dst->charged_from = src->charged_from; + dst->charge_target_from = src->charge_target_from; + dst->charge_addr_from = src->charge_addr_from; +} + static int damon_reclaim_apply_parameters(void) { - struct damos *scheme; + struct damos *scheme, *old_scheme; struct damos_filter *filter; int err = 0; @@ -164,6 +175,11 @@ static int damon_reclaim_apply_parameter scheme = damon_reclaim_new_scheme(); if (!scheme) return -ENOMEM; + if (!list_empty(&ctx->schemes)) { + damon_for_each_scheme(old_scheme, ctx) + damon_reclaim_copy_quota_status(&scheme->quota, + &old_scheme->quota); + } if (skip_anon) { filter = damos_new_filter(DAMOS_FILTER_TYPE_ANON, true); if (!filter) { _ Patches currently in -mm which might be from sj@xxxxxxxxxx are mm-damon-core-check-apply-interval-in-damon_do_apply_schemes.patch mm-damon-sysfs-schemes-handle-schemes-sysfs-dir-removal-before-commit_schemes_quota_goals.patch mm-damon-reclaim-fix-quota-stauts-loss-due-to-online-tunings.patch mm-damon-lru_sort-fix-quota-status-loss-due-to-online-tunings.patch docs-admin-guide-mm-damon-usage-use-sysfs-interface-for-tracepoints-example.patch mm-damon-rename-config_damon_dbgfs-to-damon_dbgfs_deprecated.patch mm-damon-dbgfs-implement-deprecation-notice-file.patch mm-damon-dbgfs-make-debugfs-interface-deprecation-message-a-macro.patch docs-admin-guide-mm-damon-usage-document-deprecated-file-of-damon-debugfs-interface.patch selftets-damon-prepare-for-monitor_on-file-renaming.patch mm-damon-dbgfs-rename-monitor_on-file-to-monitor_on_deprecated.patch docs-admin-guide-mm-damon-usage-update-for-monitor_on-renaming.patch docs-translations-damon-usage-update-for-monitor_on-renaming.patch mm-damon-sysfs-handle-state-file-inputs-for-every-sampling-interval-if-possible.patch selftests-damon-_damon_sysfs-support-damos-quota.patch selftests-damon-_damon_sysfs-support-damos-stats.patch selftests-damon-_damon_sysfs-support-damos-apply-interval.patch selftests-damon-add-a-test-for-damos-quota.patch selftests-damon-add-a-test-for-damos-apply-intervals.patch selftests-damon-add-a-test-for-a-race-between-target_ids_read-and-dbgfs_before_terminate.patch selftests-damon-add-a-test-for-the-pid-leak-of-dbgfs_target_ids_write.patch selftests-damon-_chk_dependency-get-debugfs-mount-point-from-proc-mounts.patch docs-mm-damon-maintainer-profile-fix-reference-links-for-mm-stable-tree.patch docs-mm-damon-move-the-list-of-damos-actions-to-design-doc.patch docs-mm-damon-move-damon-operation-sets-list-from-the-usage-to-the-design-document.patch docs-mm-damon-move-monitoring-target-regions-setup-detail-from-the-usage-to-the-design-document.patch docs-admin-guide-mm-damon-usage-fix-wrong-quotas-diabling-condition.patch mm-damon-core-set-damos_quota-esz-as-public-field-and-document.patch mm-damon-sysfs-schemes-implement-quota-effective_bytes-file.patch mm-damon-sysfs-implement-a-kdamond-command-for-updating-schemes-effective-quotas.patch docs-abi-damon-document-effective_bytes-sysfs-file.patch docs-admin-guide-mm-damon-usage-document-effective_bytes-file.patch mm-damon-move-comments-and-fields-for-damos-quota-prioritization-to-the-end.patch mm-damon-core-split-out-quota-goal-related-fields-to-a-struct.patch mm-damon-core-add-multiple-goals-per-damos_quota-and-helpers-for-those.patch mm-damon-sysfs-use-only-quota-goals.patch mm-damon-core-remove-goal-field-of-damos_quota.patch mm-damon-core-let-goal-specified-with-only-target-and-current-values.patch mm-damon-core-support-multiple-metrics-for-quota-goal.patch mm-damon-core-implement-psi-metric-damos-quota-goal.patch mm-damon-sysfs-schemes-support-psi-based-quota-auto-tune.patch docs-mm-damon-design-document-quota-goal-self-tuning.patch docs-abi-damon-document-quota-goal-metric-file.patch docs-admin-guide-mm-damon-usage-document-quota-goal-metric-file.patch mm-damon-reclaim-implement-user-feedback-driven-quota-auto-tuning.patch mm-damon-reclaim-implement-memory-psi-driven-quota-self-tuning.patch docs-admin-guide-mm-damon-reclaim-document-auto-tuning-parameters.patch