mm: rename and change semantics of nr_indirectly_reclaimable_bytes

The vmstat counter NR_INDIRECTLY_RECLAIMABLE_BYTES was introduced by
commit eb59254608 ("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>
This commit is contained in:
Vlastimil Babka 2018-10-26 15:05:46 -07:00 committed by Linus Torvalds
parent 2e03b4bc4a
commit b29940c1ab
5 changed files with 14 additions and 24 deletions

View File

@ -33,8 +33,8 @@ static void ion_page_pool_add(struct ion_page_pool *pool, struct page *page)
pool->low_count++; pool->low_count++;
} }
mod_node_page_state(page_pgdat(page), NR_INDIRECTLY_RECLAIMABLE_BYTES, mod_node_page_state(page_pgdat(page), NR_KERNEL_MISC_RECLAIMABLE,
(1 << (PAGE_SHIFT + pool->order))); 1 << pool->order);
mutex_unlock(&pool->mutex); mutex_unlock(&pool->mutex);
} }
@ -53,8 +53,8 @@ static struct page *ion_page_pool_remove(struct ion_page_pool *pool, bool high)
} }
list_del(&page->lru); list_del(&page->lru);
mod_node_page_state(page_pgdat(page), NR_INDIRECTLY_RECLAIMABLE_BYTES, mod_node_page_state(page_pgdat(page), NR_KERNEL_MISC_RECLAIMABLE,
-(1 << (PAGE_SHIFT + pool->order))); -(1 << pool->order));
return page; return page;
} }

View File

@ -180,7 +180,7 @@ enum node_stat_item {
NR_VMSCAN_IMMEDIATE, /* Prioritise for reclaim when writeback ends */ NR_VMSCAN_IMMEDIATE, /* Prioritise for reclaim when writeback ends */
NR_DIRTIED, /* page dirtyings since bootup */ NR_DIRTIED, /* page dirtyings since bootup */
NR_WRITTEN, /* page writings 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 NR_VM_NODE_STAT_ITEMS
}; };

View File

@ -4701,6 +4701,7 @@ long si_mem_available(void)
unsigned long pagecache; unsigned long pagecache;
unsigned long wmark_low = 0; unsigned long wmark_low = 0;
unsigned long pages[NR_LRU_LISTS]; unsigned long pages[NR_LRU_LISTS];
unsigned long reclaimable;
struct zone *zone; struct zone *zone;
int lru; int lru;
@ -4726,19 +4727,13 @@ long si_mem_available(void)
available += pagecache; available += pagecache;
/* /*
* Part of the reclaimable slab consists of items that are in use, * Part of the reclaimable slab and other kernel memory consists of
* and cannot be freed. Cap this estimate at the low watermark. * items that are in use, and cannot be freed. Cap this estimate at the
* low watermark.
*/ */
available += global_node_page_state(NR_SLAB_RECLAIMABLE) - reclaimable = global_node_page_state(NR_SLAB_RECLAIMABLE) +
min(global_node_page_state(NR_SLAB_RECLAIMABLE) / 2, global_node_page_state(NR_KERNEL_MISC_RECLAIMABLE);
wmark_low); available += reclaimable - min(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;
if (available < 0) if (available < 0)
available = 0; available = 0;

View File

@ -678,8 +678,7 @@ int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin)
* Part of the kernel memory, which can be released * Part of the kernel memory, which can be released
* under memory pressure. * under memory pressure.
*/ */
free += global_node_page_state( free += global_node_page_state(NR_KERNEL_MISC_RECLAIMABLE);
NR_INDIRECTLY_RECLAIMABLE_BYTES) >> PAGE_SHIFT;
/* /*
* Leave reserved pages. The pages are not for anonymous pages. * Leave reserved pages. The pages are not for anonymous pages.

View File

@ -1161,7 +1161,7 @@ const char * const vmstat_text[] = {
"nr_vmscan_immediate_reclaim", "nr_vmscan_immediate_reclaim",
"nr_dirtied", "nr_dirtied",
"nr_written", "nr_written",
"", /* nr_indirectly_reclaimable */ "nr_kernel_misc_reclaimable",
/* enum writeback_stat_item counters */ /* enum writeback_stat_item counters */
"nr_dirty_threshold", "nr_dirty_threshold",
@ -1706,10 +1706,6 @@ static int vmstat_show(struct seq_file *m, void *arg)
unsigned long *l = arg; unsigned long *l = arg;
unsigned long off = l - (unsigned long *)m->private; 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_puts(m, vmstat_text[off]);
seq_put_decimal_ull(m, " ", *l); seq_put_decimal_ull(m, " ", *l);
seq_putc(m, '\n'); seq_putc(m, '\n');