zsmalloc: show per fullness group class stats

We keep the old fullness (3/4 threshold) reporting in
zs_stats_size_show().  Switch from allmost full/empty stats to
fine-grained per inuse ratio (fullness group) reporting, which gives
signicantly more data on classes fragmentation.

Link: https://lkml.kernel.org/r/20230304034835.2082479-5-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index a61540a..aea50e2 100644 (file)
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -172,9 +172,7 @@
 enum fullness_group {
        ZS_INUSE_RATIO_0,
        ZS_INUSE_RATIO_10,
-       /* NOTE: 5 more fullness groups here */
-       ZS_INUSE_RATIO_70       = 7,
-       /* NOTE: 2 more fullness groups here */
+       /* NOTE: 8 more fullness groups here */
        ZS_INUSE_RATIO_99       = 10,
        ZS_INUSE_RATIO_100,
        NR_FULLNESS_GROUPS,
@@ -621,23 +619,22 @@ static unsigned long zs_can_compact(struct size_class *class);
 
 static int zs_stats_size_show(struct seq_file *s, void *v)
 {
-       int i;
+       int i, fg;
        struct zs_pool *pool = s->private;
        struct size_class *class;
        int objs_per_zspage;
-       unsigned long class_almost_full, class_almost_empty;
        unsigned long obj_allocated, obj_used, pages_used, freeable;
-       unsigned long total_class_almost_full = 0, total_class_almost_empty = 0;
        unsigned long total_objs = 0, total_used_objs = 0, total_pages = 0;
        unsigned long total_freeable = 0;
+       unsigned long inuse_totals[NR_FULLNESS_GROUPS] = {0, };
 
-       seq_printf(s, " %5s %5s %11s %12s %13s %10s %10s %16s %8s\n",
-                       "class", "size", "almost_full", "almost_empty",
+       seq_printf(s, " %5s %5s %9s %9s %9s %9s %9s %9s %9s %9s %9s %9s %9s %13s %10s %10s %16s %8s\n",
+                       "class", "size", "10%", "20%", "30%", "40%",
+                       "50%", "60%", "70%", "80%", "90%", "99%", "100%",
                        "obj_allocated", "obj_used", "pages_used",
                        "pages_per_zspage", "freeable");
 
        for (i = 0; i < ZS_SIZE_CLASSES; i++) {
-               int fg;
 
                class = pool->size_class[i];
 
@@ -645,16 +642,12 @@ static int zs_stats_size_show(struct seq_file *s, void *v)
                        continue;
 
                spin_lock(&pool->lock);
-               class_almost_full = 0;
-               class_almost_empty = 0;
-               /*
-                * Replicate old behaviour for almost_full and almost_empty
-                * stats.
-                */
-               for (fg = ZS_INUSE_RATIO_70; fg <= ZS_INUSE_RATIO_99; fg++)
-                       class_almost_full += zs_stat_get(class, fg);
-               for (fg = ZS_INUSE_RATIO_10; fg < ZS_INUSE_RATIO_70; fg++)
-                       class_almost_empty += zs_stat_get(class, fg);
+
+               seq_printf(s, " %5u %5u ", i, class->size);
+               for (fg = ZS_INUSE_RATIO_10; fg < NR_FULLNESS_GROUPS; fg++) {
+                       inuse_totals[fg] += zs_stat_get(class, fg);
+                       seq_printf(s, "%9lu ", zs_stat_get(class, fg));
+               }
 
                obj_allocated = zs_stat_get(class, ZS_OBJS_ALLOCATED);
                obj_used = zs_stat_get(class, ZS_OBJS_INUSE);
@@ -665,14 +658,10 @@ static int zs_stats_size_show(struct seq_file *s, void *v)
                pages_used = obj_allocated / objs_per_zspage *
                                class->pages_per_zspage;
 
-               seq_printf(s, " %5u %5u %11lu %12lu %13lu"
-                               " %10lu %10lu %16d %8lu\n",
-                       i, class->size, class_almost_full, class_almost_empty,
-                       obj_allocated, obj_used, pages_used,
-                       class->pages_per_zspage, freeable);
+               seq_printf(s, "%13lu %10lu %10lu %16d %8lu\n",
+                          obj_allocated, obj_used, pages_used,
+                          class->pages_per_zspage, freeable);
 
-               total_class_almost_full += class_almost_full;
-               total_class_almost_empty += class_almost_empty;
                total_objs += obj_allocated;
                total_used_objs += obj_used;
                total_pages += pages_used;
@@ -680,10 +669,14 @@ static int zs_stats_size_show(struct seq_file *s, void *v)
        }
 
        seq_puts(s, "\n");
-       seq_printf(s, " %5s %5s %11lu %12lu %13lu %10lu %10lu %16s %8lu\n",
-                       "Total", "", total_class_almost_full,
-                       total_class_almost_empty, total_objs,
-                       total_used_objs, total_pages, "", total_freeable);
+       seq_printf(s, " %5s %5s ", "Total", "");
+
+       for (fg = ZS_INUSE_RATIO_10; fg < NR_FULLNESS_GROUPS; fg++)
+               seq_printf(s, "%9lu ", inuse_totals[fg]);
+
+       seq_printf(s, "%13lu %10lu %10lu %16s %8lu\n",
+                  total_objs, total_used_objs, total_pages, "",
+                  total_freeable);
 
        return 0;
 }