The patch titled Subject: mm, vmscan: avoid passing in remaining unnecessarily to prepare_kswapd_sleep has been added to the -mm tree. Its filename is mm-vmscan-avoid-passing-in-remaining-unnecessarily-to-prepare_kswapd_sleep.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-vmscan-avoid-passing-in-remaining-unnecessarily-to-prepare_kswapd_sleep.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-vmscan-avoid-passing-in-remaining-unnecessarily-to-prepare_kswapd_sleep.patch 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/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx> Subject: mm, vmscan: avoid passing in remaining unnecessarily to prepare_kswapd_sleep As pointed out by Minchan Kim, the first call to prepare_kswapd_sleep always passes in 0 for remaining and the second call can trivially check the parameter in advance. Suggested-by: Minchan Kim <minchan@xxxxxxxxxx> Link: http://lkml.kernel.org/r/1467970510-21195-27-git-send-email-mgorman@xxxxxxxxxxxxxxxxxxx Signed-off-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx> Cc: Hillf Danton <hillf.zj@xxxxxxxxxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxxxx> Cc: Minchan Kim <minchan@xxxxxxxxxx> Cc: Rik van Riel <riel@xxxxxxxxxxx> Cc: Vlastimil Babka <vbabka@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/vmscan.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) diff -puN mm/vmscan.c~mm-vmscan-avoid-passing-in-remaining-unnecessarily-to-prepare_kswapd_sleep mm/vmscan.c --- a/mm/vmscan.c~mm-vmscan-avoid-passing-in-remaining-unnecessarily-to-prepare_kswapd_sleep +++ a/mm/vmscan.c @@ -3020,15 +3020,10 @@ static bool zone_balanced(struct zone *z * * Returns true if kswapd is ready to sleep */ -static bool prepare_kswapd_sleep(pg_data_t *pgdat, int order, long remaining, - int classzone_idx) +static bool prepare_kswapd_sleep(pg_data_t *pgdat, int order, int classzone_idx) { int i; - /* If a direct reclaimer woke kswapd within HZ/10, it's premature */ - if (remaining) - return false; - /* * The throttled processes are normally woken up in balance_pgdat() as * soon as pfmemalloc_watermark_ok() is true. But there is a potential @@ -3243,7 +3238,7 @@ static void kswapd_try_to_sleep(pg_data_ prepare_to_wait(&pgdat->kswapd_wait, &wait, TASK_INTERRUPTIBLE); /* Try to sleep for a short interval */ - if (prepare_kswapd_sleep(pgdat, reclaim_order, remaining, classzone_idx)) { + if (prepare_kswapd_sleep(pgdat, reclaim_order, classzone_idx)) { /* * Compaction records what page blocks it recently failed to * isolate pages from and skips them in the future scanning. @@ -3278,7 +3273,8 @@ static void kswapd_try_to_sleep(pg_data_ * After a short sleep, check if it was a premature sleep. If not, then * go fully to sleep until explicitly woken up. */ - if (prepare_kswapd_sleep(pgdat, reclaim_order, remaining, classzone_idx)) { + if (!remaining && + prepare_kswapd_sleep(pgdat, reclaim_order, classzone_idx)) { trace_mm_vmscan_kswapd_sleep(pgdat->node_id); /* _ Patches currently in -mm which might be from mgorman@xxxxxxxxxxxxxxxxxxx are mm-meminit-always-return-a-valid-node-from-early_pfn_to_nid.patch mm-meminit-ensure-node-is-online-before-checking-whether-pages-are-uninitialised.patch mm-meminit-remove-early_page_nid_uninitialised.patch mm-vmstat-add-infrastructure-for-per-node-vmstats.patch mm-vmscan-move-lru_lock-to-the-node.patch mm-vmscan-move-lru-lists-to-node.patch mm-mmzone-clarify-the-usage-of-zone-padding.patch mm-vmscan-begin-reclaiming-pages-on-a-per-node-basis.patch mm-vmscan-have-kswapd-only-scan-based-on-the-highest-requested-zone.patch mm-vmscan-make-kswapd-reclaim-in-terms-of-nodes.patch mm-vmscan-remove-balance-gap.patch mm-vmscan-simplify-the-logic-deciding-whether-kswapd-sleeps.patch mm-vmscan-by-default-have-direct-reclaim-only-shrink-once-per-node.patch mm-vmscan-remove-duplicate-logic-clearing-node-congestion-and-dirty-state.patch mm-vmscan-do-not-reclaim-from-kswapd-if-there-is-any-eligible-zone.patch mm-vmscan-make-shrink_node-decisions-more-node-centric.patch mm-memcg-move-memcg-limit-enforcement-from-zones-to-nodes.patch mm-workingset-make-working-set-detection-node-aware.patch mm-page_alloc-consider-dirtyable-memory-in-terms-of-nodes.patch mm-move-page-mapped-accounting-to-the-node.patch mm-rename-nr_anon_pages-to-nr_anon_mapped.patch mm-move-most-file-based-accounting-to-the-node.patch mm-move-vmscan-writes-and-file-write-accounting-to-the-node.patch mm-vmscan-only-wakeup-kswapd-once-per-node-for-the-requested-classzone.patch mm-page_alloc-wake-kswapd-based-on-the-highest-eligible-zone.patch mm-convert-zone_reclaim-to-node_reclaim.patch mm-vmscan-avoid-passing-in-classzone_idx-unnecessarily-to-shrink_node.patch mm-vmscan-avoid-passing-in-classzone_idx-unnecessarily-to-compaction_ready.patch mm-vmscan-avoid-passing-in-remaining-unnecessarily-to-prepare_kswapd_sleep.patch mm-vmscan-have-kswapd-reclaim-from-all-zones-if-reclaiming-and-buffer_heads_over_limit.patch mm-vmscan-add-classzone-information-to-tracepoints.patch mm-page_alloc-remove-fair-zone-allocation-policy.patch mm-page_alloc-cache-the-last-node-whose-dirty-limit-is-reached.patch mm-vmstat-replace-__count_zone_vm_events-with-a-zone-id-equivalent.patch mm-vmstat-account-per-zone-stalls-and-pages-skipped-during-reclaim.patch mm-vmstat-print-node-based-stats-in-zoneinfo-file.patch mm-vmstat-remove-zone-and-node-double-accounting-by-approximating-retries.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html