From: Vlastimil Babka vbabka@suse.cz
mainline inclusion from mainline-4.20-rc1 commit b29940c1abd7a4c3abeb926df0a5ec84d6902d47 category: bugfix bugzilla: 34611 CVE: NA
------------------------------------------------- The vmstat counter NR_INDIRECTLY_RECLAIMABLE_BYTES was introduced by commit eb59254608bc ("mm: introduce NR_INDIRECTLY_RECLAIMABLE_BYTES") with the goal of accounting objects that can be reclaimed, but cannot be allocated via a SLAB_RECLAIM_ACCOUNT cache. This is now possible via kmalloc() with __GFP_RECLAIMABLE flag, and the dcache external names user is converted.
The counter is however still useful for accounting direct page allocations (i.e. not slab) with a shrinker, such as the ION page pool. So keep it, and:
- change granularity to pages to be more like other counters; sub-page allocations should be able to use kmalloc - rename the counter to NR_KERNEL_MISC_RECLAIMABLE - expose the counter again in vmstat as "nr_kernel_misc_reclaimable"; we can again remove the check for not printing "hidden" counters
Link: http://lkml.kernel.org/r/20180731090649.16028-5-vbabka@suse.cz Signed-off-by: Vlastimil Babka vbabka@suse.cz Acked-by: Christoph Lameter cl@linux.com Acked-by: Roman Gushchin guro@fb.com Cc: Vijayanand Jitta vjitta@codeaurora.org Cc: Laura Abbott labbott@redhat.com Cc: Sumit Semwal sumit.semwal@linaro.org Cc: David Rientjes rientjes@google.com Cc: Johannes Weiner hannes@cmpxchg.org Cc: Joonsoo Kim iamjoonsoo.kim@lge.com Cc: Matthew Wilcox willy@infradead.org Cc: Mel Gorman mgorman@techsingularity.net Cc: Michal Hocko mhocko@kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org (cherry picked from commit b29940c1abd7a4c3abeb926df0a5ec84d6902d47) Signed-off-by: Kefeng Wang wangkefeng.wang@huawei.com Signed-off-by: Liu Shixin liushixin2@huawei.com Reviewed-by: Kefeng Wang wangkefeng.wang@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- drivers/staging/android/ion/ion_page_pool.c | 8 ++++---- include/linux/mmzone.h | 2 +- mm/page_alloc.c | 19 +++++++------------ mm/util.c | 3 +-- mm/vmstat.c | 6 +----- 5 files changed, 14 insertions(+), 24 deletions(-)
diff --git a/drivers/staging/android/ion/ion_page_pool.c b/drivers/staging/android/ion/ion_page_pool.c index 890d264ac687..fd1f501da669 100644 --- a/drivers/staging/android/ion/ion_page_pool.c +++ b/drivers/staging/android/ion/ion_page_pool.c @@ -36,8 +36,8 @@ static void ion_page_pool_add(struct ion_page_pool *pool, struct page *page) pool->low_count++; }
- mod_node_page_state(page_pgdat(page), NR_INDIRECTLY_RECLAIMABLE_BYTES, - (1 << (PAGE_SHIFT + pool->order))); + mod_node_page_state(page_pgdat(page), NR_KERNEL_MISC_RECLAIMABLE, + 1 << pool->order); mutex_unlock(&pool->mutex); }
@@ -56,8 +56,8 @@ static struct page *ion_page_pool_remove(struct ion_page_pool *pool, bool high) }
list_del(&page->lru); - mod_node_page_state(page_pgdat(page), NR_INDIRECTLY_RECLAIMABLE_BYTES, - -(1 << (PAGE_SHIFT + pool->order))); + mod_node_page_state(page_pgdat(page), NR_KERNEL_MISC_RECLAIMABLE, + -(1 << pool->order)); return page; }
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 51f74519b0e8..4133cd6d6a34 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -181,7 +181,7 @@ enum node_stat_item { NR_VMSCAN_IMMEDIATE, /* Prioritise for reclaim when writeback ends */ NR_DIRTIED, /* page dirtyings since bootup */ NR_WRITTEN, /* page writings since bootup */ - NR_INDIRECTLY_RECLAIMABLE_BYTES, /* measured in bytes */ + NR_KERNEL_MISC_RECLAIMABLE, /* reclaimable non-slab kernel pages */ NR_VM_NODE_STAT_ITEMS };
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index e394ae5ba2a7..1e0aeebfb293 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -4830,6 +4830,7 @@ long si_mem_available(void) unsigned long pagecache; unsigned long wmark_low = 0; unsigned long pages[NR_LRU_LISTS]; + unsigned long reclaimable; struct zone *zone; int lru;
@@ -4855,19 +4856,13 @@ long si_mem_available(void) available += pagecache;
/* - * Part of the reclaimable slab consists of items that are in use, - * and cannot be freed. Cap this estimate at the low watermark. + * Part of the reclaimable slab and other kernel memory consists of + * items that are in use, and cannot be freed. Cap this estimate at the + * low watermark. */ - available += global_node_page_state(NR_SLAB_RECLAIMABLE) - - min(global_node_page_state(NR_SLAB_RECLAIMABLE) / 2, - wmark_low); - - /* - * Part of the kernel memory, which can be released under memory - * pressure. - */ - available += global_node_page_state(NR_INDIRECTLY_RECLAIMABLE_BYTES) >> - PAGE_SHIFT; + reclaimable = global_node_page_state(NR_SLAB_RECLAIMABLE) + + global_node_page_state(NR_KERNEL_MISC_RECLAIMABLE); + available += reclaimable - min(reclaimable / 2, wmark_low);
if (available < 0) available = 0; diff --git a/mm/util.c b/mm/util.c index ed64ef1f8387..5dc02e916a19 100644 --- a/mm/util.c +++ b/mm/util.c @@ -706,8 +706,7 @@ int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin) * Part of the kernel memory, which can be released * under memory pressure. */ - free += global_node_page_state( - NR_INDIRECTLY_RECLAIMABLE_BYTES) >> PAGE_SHIFT; + free += global_node_page_state(NR_KERNEL_MISC_RECLAIMABLE);
/* * Leave reserved pages. The pages are not for anonymous pages. diff --git a/mm/vmstat.c b/mm/vmstat.c index 96028cc96f2f..acc9f1c6b43a 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -1161,7 +1161,7 @@ const char * const vmstat_text[] = { "nr_vmscan_immediate_reclaim", "nr_dirtied", "nr_written", - "", /* nr_indirectly_reclaimable */ + "nr_kernel_misc_reclaimable",
/* enum writeback_stat_item counters */ "nr_dirty_threshold", @@ -1722,10 +1722,6 @@ static int vmstat_show(struct seq_file *m, void *arg) unsigned long *l = arg; unsigned long off = l - (unsigned long *)m->private;
- /* Skip hidden vmstat items. */ - if (*vmstat_text[off] == '\0') - return 0; - seq_puts(m, vmstat_text[off]); seq_put_decimal_ull(m, " ", *l); seq_putc(m, '\n');