mm: memcontrol: re-use global VM event enum

The current duplication is a high-maintenance mess, and it's painful to
add new items.

This increases the size of the event array, but we'll eventually want
most of the VM events tracked on a per-cgroup basis anyway.

Link: http://lkml.kernel.org/r/20170404220148.28338-2-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index bc0c16e284c0aa2409e2ab13f86c37e9c5ae8f02..0bb5f055bd263ee54c1fbad705da0a1b457a2f6f 100644 (file)
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -69,20 +69,6 @@ struct mem_cgroup_reclaim_cookie {
        unsigned int generation;
 };
 
-enum mem_cgroup_events_index {
-       MEM_CGROUP_EVENTS_PGPGIN,       /* # of pages paged in */
-       MEM_CGROUP_EVENTS_PGPGOUT,      /* # of pages paged out */
-       MEM_CGROUP_EVENTS_PGFAULT,      /* # of page-faults */
-       MEM_CGROUP_EVENTS_PGMAJFAULT,   /* # of major page-faults */
-       MEM_CGROUP_EVENTS_NSTATS,
-       /* default hierarchy events */
-       MEMCG_LOW = MEM_CGROUP_EVENTS_NSTATS,
-       MEMCG_HIGH,
-       MEMCG_MAX,
-       MEMCG_OOM,
-       MEMCG_NR_EVENTS,
-};
-
 /*
  * Per memcg event counter is incremented at every pagein/pageout. With THP,
  * it will be incremated by the number of pages. This counter is used for
@@ -106,6 +92,15 @@ struct mem_cgroup_id {
        atomic_t ref;
 };
 
+/* Cgroup-specific events, on top of universal VM events */
+enum memcg_event_item {
+       MEMCG_LOW = NR_VM_EVENT_ITEMS,
+       MEMCG_HIGH,
+       MEMCG_MAX,
+       MEMCG_OOM,
+       MEMCG_NR_EVENTS,
+};
+
 struct mem_cgroup_stat_cpu {
        long count[MEMCG_NR_STAT];
        unsigned long events[MEMCG_NR_EVENTS];
@@ -288,9 +283,9 @@ static inline bool mem_cgroup_disabled(void)
 }
 
 static inline void mem_cgroup_event(struct mem_cgroup *memcg,
-                                   enum mem_cgroup_events_index idx)
+                                   enum memcg_event_item event)
 {
-       this_cpu_inc(memcg->stat->events[idx]);
+       this_cpu_inc(memcg->stat->events[event]);
        cgroup_file_notify(&memcg->events_file);
 }
 
@@ -575,20 +570,8 @@ static inline void mem_cgroup_count_vm_event(struct mm_struct *mm,
 
        rcu_read_lock();
        memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
-       if (unlikely(!memcg))
-               goto out;
-
-       switch (idx) {
-       case PGFAULT:
-               this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGFAULT]);
-               break;
-       case PGMAJFAULT:
-               this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGMAJFAULT]);
-               break;
-       default:
-               BUG();
-       }
-out:
+       if (likely(memcg))
+               this_cpu_inc(memcg->stat->events[idx]);
        rcu_read_unlock();
 }
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
@@ -608,7 +591,7 @@ static inline bool mem_cgroup_disabled(void)
 }
 
 static inline void mem_cgroup_event(struct mem_cgroup *memcg,
-                                   enum mem_cgroup_events_index idx)
+                                   enum memcg_event_item event)
 {
 }
 

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 1ffa3ad201ea1ead144c2acead2fd78cd208cedb..6b42887e5f1459a098c8acdc48ec5d020f09dde0 100644 (file)
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -111,13 +111,6 @@ static const char * const mem_cgroup_stat_names[] = {
        "swap",
 };
 
-static const char * const mem_cgroup_events_names[] = {
-       "pgpgin",
-       "pgpgout",
-       "pgfault",
-       "pgmajfault",
-};
-
 static const char * const mem_cgroup_lru_names[] = {
        "inactive_anon",
        "active_anon",
@@ -571,13 +564,13 @@ mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_node *mctz)
  */
 
 static unsigned long mem_cgroup_read_events(struct mem_cgroup *memcg,
-                                           enum mem_cgroup_events_index idx)
+                                           enum memcg_event_item event)
 {
        unsigned long val = 0;
        int cpu;
 
        for_each_possible_cpu(cpu)
-               val += per_cpu(memcg->stat->events[idx], cpu);
+               val += per_cpu(memcg->stat->events[event], cpu);
        return val;
 }
 
@@ -608,9 +601,9 @@ static void mem_cgroup_charge_statistics(struct mem_cgroup *memcg,
 
        /* pagein of a big page is an event. So, ignore page size */
        if (nr_pages > 0)
-               __this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGPGIN]);
+               __this_cpu_inc(memcg->stat->events[PGPGIN]);
        else {
-               __this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGPGOUT]);
+               __this_cpu_inc(memcg->stat->events[PGPGOUT]);
                nr_pages = -nr_pages; /* for event */
        }
 
@@ -3119,6 +3112,21 @@ static int memcg_numa_stat_show(struct seq_file *m, void *v)
 }
 #endif /* CONFIG_NUMA */
 
+/* Universal VM events cgroup1 shows, original sort order */
+unsigned int memcg1_events[] = {
+       PGPGIN,
+       PGPGOUT,
+       PGFAULT,
+       PGMAJFAULT,
+};
+
+static const char *const memcg1_event_names[] = {
+       "pgpgin",
+       "pgpgout",
+       "pgfault",
+       "pgmajfault",
+};
+
 static int memcg_stat_show(struct seq_file *m, void *v)
 {
        struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m));
@@ -3128,8 +3136,6 @@ static int memcg_stat_show(struct seq_file *m, void *v)
 
        BUILD_BUG_ON(ARRAY_SIZE(mem_cgroup_stat_names) !=
                     MEM_CGROUP_STAT_NSTATS);
-       BUILD_BUG_ON(ARRAY_SIZE(mem_cgroup_events_names) !=
-                    MEM_CGROUP_EVENTS_NSTATS);
        BUILD_BUG_ON(ARRAY_SIZE(mem_cgroup_lru_names) != NR_LRU_LISTS);
 
        for (i = 0; i < MEM_CGROUP_STAT_NSTATS; i++) {
@@ -3139,9 +3145,9 @@ static int memcg_stat_show(struct seq_file *m, void *v)
                           mem_cgroup_read_stat(memcg, i) * PAGE_SIZE);
        }
 
-       for (i = 0; i < MEM_CGROUP_EVENTS_NSTATS; i++)
-               seq_printf(m, "%s %lu\n", mem_cgroup_events_names[i],
-                          mem_cgroup_read_events(memcg, i));
+       for (i = 0; i < ARRAY_SIZE(memcg1_events); i++)
+               seq_printf(m, "%s %lu\n", memcg1_event_names[i],
+                          mem_cgroup_read_events(memcg, memcg1_events[i]));
 
        for (i = 0; i < NR_LRU_LISTS; i++)
                seq_printf(m, "%s %lu\n", mem_cgroup_lru_names[i],
@@ -3169,13 +3175,12 @@ static int memcg_stat_show(struct seq_file *m, void *v)
                seq_printf(m, "total_%s %llu\n", mem_cgroup_stat_names[i], val);
        }
 
-       for (i = 0; i < MEM_CGROUP_EVENTS_NSTATS; i++) {
+       for (i = 0; i < ARRAY_SIZE(memcg1_events); i++) {
                unsigned long long val = 0;
 
                for_each_mem_cgroup_tree(mi, memcg)
-                       val += mem_cgroup_read_events(mi, i);
-               seq_printf(m, "total_%s %llu\n",
-                          mem_cgroup_events_names[i], val);
+                       val += mem_cgroup_read_events(mi, memcg1_events[i]);
+               seq_printf(m, "total_%s %llu\n", memcg1_event_names[i], val);
        }
 
        for (i = 0; i < NR_LRU_LISTS; i++) {
@@ -5222,10 +5227,8 @@ static int memory_stat_show(struct seq_file *m, void *v)
 
        /* Accumulated memory events */
 
-       seq_printf(m, "pgfault %lu\n",
-                  events[MEM_CGROUP_EVENTS_PGFAULT]);
-       seq_printf(m, "pgmajfault %lu\n",
-                  events[MEM_CGROUP_EVENTS_PGMAJFAULT]);
+       seq_printf(m, "pgfault %lu\n", events[PGFAULT]);
+       seq_printf(m, "pgmajfault %lu\n", events[PGMAJFAULT]);
 
        seq_printf(m, "workingset_refault %lu\n",
                   stat[MEMCG_WORKINGSET_REFAULT]);
@@ -5493,7 +5496,7 @@ static void uncharge_batch(struct mem_cgroup *memcg, unsigned long pgpgout,
        __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_CACHE], nr_file);
        __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_RSS_HUGE], nr_huge);
        __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_SHMEM], nr_shmem);
-       __this_cpu_add(memcg->stat->events[MEM_CGROUP_EVENTS_PGPGOUT], pgpgout);
+       __this_cpu_add(memcg->stat->events[PGPGOUT], pgpgout);
        __this_cpu_add(memcg->stat->nr_page_events, nr_pages);
        memcg_check_events(memcg, dummy_page);
        local_irq_restore(flags);