From: Johannes Weiner <hannes@xxxxxxxxxxx> Subject: mm: workingset: add vmstat counter for shadow nodes Make it easier to catch bugs in the shadow node shrinker by adding a counter for the shadow nodes in circulation. [akpm@xxxxxxxxxxxxxxxxxxxx: assert that irqs are disabled, for __inc_lruvec_page_state()] [akpm@xxxxxxxxxxxxxxxxxxxx: s/WARN_ON_ONCE/VM_WARN_ON_ONCE/, per Johannes] Link: http://lkml.kernel.org/r/20181009184732.762-4-hannes@xxxxxxxxxxx Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx> Reviewed-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Cc: Rik van Riel <riel@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/mmzone.h | 1 + mm/vmstat.c | 1 + mm/workingset.c | 14 ++++++++++++-- 3 files changed, 14 insertions(+), 2 deletions(-) --- a/include/linux/mmzone.h~mm-workingset-add-vmstat-counter-for-shadow-nodes +++ a/include/linux/mmzone.h @@ -161,6 +161,7 @@ enum node_stat_item { NR_SLAB_UNRECLAIMABLE, NR_ISOLATED_ANON, /* Temporary isolated pages from anon lru */ NR_ISOLATED_FILE, /* Temporary isolated pages from file lru */ + WORKINGSET_NODES, WORKINGSET_REFAULT, WORKINGSET_ACTIVATE, WORKINGSET_RESTORE, --- a/mm/vmstat.c~mm-workingset-add-vmstat-counter-for-shadow-nodes +++ a/mm/vmstat.c @@ -1143,6 +1143,7 @@ const char * const vmstat_text[] = { "nr_slab_unreclaimable", "nr_isolated_anon", "nr_isolated_file", + "workingset_nodes", "workingset_refault", "workingset_activate", "workingset_restore", --- a/mm/workingset.c~mm-workingset-add-vmstat-counter-for-shadow-nodes +++ a/mm/workingset.c @@ -377,12 +377,20 @@ void workingset_update_node(struct radix * already where they should be. The list_empty() test is safe * as node->private_list is protected by the i_pages lock. */ + VM_WARN_ON_ONCE(!irqs_disabled()); /* For __inc_lruvec_page_state */ + if (node->count && node->count == node->exceptional) { - if (list_empty(&node->private_list)) + if (list_empty(&node->private_list)) { list_lru_add(&shadow_nodes, &node->private_list); + __inc_lruvec_page_state(virt_to_page(node), + WORKINGSET_NODES); + } } else { - if (!list_empty(&node->private_list)) + if (!list_empty(&node->private_list)) { list_lru_del(&shadow_nodes, &node->private_list); + __dec_lruvec_page_state(virt_to_page(node), + WORKINGSET_NODES); + } } } @@ -473,6 +481,8 @@ static enum lru_status shadow_lru_isolat } list_lru_isolate(lru, item); + __dec_lruvec_page_state(virt_to_page(node), WORKINGSET_NODES); + spin_unlock(lru_lock); /* _
