zram: use atomic64_t for all zram stats

This is a preparation patch for stats code duplication removal.

1) use atomic64_t for `pages_zero' and `pages_stored' zram stats.

2) `compr_size' and `pages_zero' struct zram_stats members did not
   follow the existing device attr naming scheme: zram_stats.ATTR has
   ATTR_show() function.  rename them:

   -- compr_size -> compr_data_size
   -- pages_zero -> zero_pages

Minchan Kim's note:
 If we really have trouble with atomic stat operation, we could
 change it with percpu_counter so that it could solve atomic overhead and
 unnecessary memory space by introducing unsigned long instead of 64bit
 atomic_t.

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Acked-by: Jerome Marchand <jmarchan@redhat.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 9 insertions, 9 deletions

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 995304ef40bb..1bf97b2f8f3f 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -109,7 +109,7 @@ static ssize_t zero_pages_show(struct device *dev,
 {
         struct zram *zram = dev_to_zram(dev);
 
-        return sprintf(buf, "%u\n", atomic_read(&zram->stats.pages_zero));
+        return sprintf(buf, "%llu\n", (u64)atomic64_read(&zram->stats.zero_pages));
 }
 
 static ssize_t orig_data_size_show(struct device *dev,
@@ -118,7 +118,7 @@ static ssize_t orig_data_size_show(struct device *dev,
         struct zram *zram = dev_to_zram(dev);
 
         return sprintf(buf, "%llu\n",
-                (u64)(atomic_read(&zram->stats.pages_stored)) << PAGE_SHIFT);
+                (u64)(atomic64_read(&zram->stats.pages_stored)) << PAGE_SHIFT);
 }
 
 static ssize_t compr_data_size_show(struct device *dev,
@@ -127,7 +127,7 @@ static ssize_t compr_data_size_show(struct device *dev,
         struct zram *zram = dev_to_zram(dev);
 
         return sprintf(buf, "%llu\n",
-                        (u64)atomic64_read(&zram->stats.compr_size));
+                        (u64)atomic64_read(&zram->stats.compr_data_size));
 }
 
 static ssize_t mem_used_total_show(struct device *dev,
@@ -301,15 +301,15 @@ static void zram_free_page(struct zram *zram, size_t index)
                  */
                 if (zram_test_flag(meta, index, ZRAM_ZERO)) {
                         zram_clear_flag(meta, index, ZRAM_ZERO);
-                        atomic_dec(&zram->stats.pages_zero);
+                        atomic64_dec(&zram->stats.zero_pages);
                 }
                 return;
         }
 
         zs_free(meta->mem_pool, handle);
 
-        atomic64_sub(meta->table[index].size, &zram->stats.compr_size);
-        atomic_dec(&zram->stats.pages_stored);
+        atomic64_sub(meta->table[index].size, &zram->stats.compr_data_size);
+        atomic64_dec(&zram->stats.pages_stored);
 
         meta->table[index].handle = 0;
         meta->table[index].size = 0;
@@ -452,7 +452,7 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
                 zram_set_flag(meta, index, ZRAM_ZERO);
                 write_unlock(&zram->meta->tb_lock);
 
-                atomic_inc(&zram->stats.pages_zero);
+                atomic64_inc(&zram->stats.zero_pages);
                 ret = 0;
                 goto out;
         }
@@ -508,8 +508,8 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
         write_unlock(&zram->meta->tb_lock);
 
         /* Update stats */
-        atomic64_add(clen, &zram->stats.compr_size);
-        atomic_inc(&zram->stats.pages_stored);
+        atomic64_add(clen, &zram->stats.compr_data_size);
+        atomic64_inc(&zram->stats.pages_stored);
 out:
         if (locked)
                 mutex_unlock(&meta->buffer_lock);