Although the ratio of the slab is one, we also should read the ratio
from the related memory_stats instead of hard-coding. And the local
variable of size is already the value of slab_unreclaimable. So we
do not need to read again. Simplify the code here.

Signed-off-by: Muchun Song <songmuc...@bytedance.com>
Acked-by: Roman Gushchin <g...@fb.com>
---
Changes in v2:
 - Add a comment in the memory_stat_format() suggested by Roman.

 mm/memcontrol.c | 26 +++++++++++++++++++++-----
 1 file changed, 21 insertions(+), 5 deletions(-)

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 9922f1510956..75df129b7a52 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1545,12 +1545,22 @@ static int __init memory_stats_init(void)
        int i;
 
        for (i = 0; i < ARRAY_SIZE(memory_stats); i++) {
+               switch (memory_stats[i].idx) {
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
-               if (memory_stats[i].idx == NR_ANON_THPS ||
-                   memory_stats[i].idx == NR_FILE_THPS ||
-                   memory_stats[i].idx == NR_SHMEM_THPS)
+               case NR_ANON_THPS:
+               case NR_FILE_THPS:
+               case NR_SHMEM_THPS:
                        memory_stats[i].ratio = HPAGE_PMD_SIZE;
+                       break;
 #endif
+               case NR_SLAB_UNRECLAIMABLE_B:
+                       VM_BUG_ON(i < 1);
+                       VM_BUG_ON(memory_stats[i - 1].idx != 
NR_SLAB_RECLAIMABLE_B);
+                       break;
+               default:
+                       break;
+               }
+
                VM_BUG_ON(!memory_stats[i].ratio);
                VM_BUG_ON(memory_stats[i].idx >= MEMCG_NR_STAT);
        }
@@ -1586,9 +1596,15 @@ static char *memory_stat_format(struct mem_cgroup *memcg)
                size *= memory_stats[i].ratio;
                seq_buf_printf(&s, "%s %llu\n", memory_stats[i].name, size);
 
+               /*
+                * We are printing reclaimable, unreclaimable of the slab
+                * and the sum of both.
+                */
                if (unlikely(memory_stats[i].idx == NR_SLAB_UNRECLAIMABLE_B)) {
-                       size = memcg_page_state(memcg, NR_SLAB_RECLAIMABLE_B) +
-                              memcg_page_state(memcg, NR_SLAB_UNRECLAIMABLE_B);
+                       int idx = i - 1;
+
+                       size += memcg_page_state(memcg, memory_stats[idx].idx) *
+                               memory_stats[idx].ratio;
                        seq_buf_printf(&s, "slab %llu\n", size);
                }
        }
-- 
2.11.0

Reply via email to