zram: use atomic64_xxx() to replace zram_stat64_xxx()
Use atomic64_xxx() to replace open-coded zram_stat64_xxx().
Some architectures have native support of atomic64 operations,
so we can get rid of the spin_lock() in zram_stat64_xxx().
On the other hand, for platforms use generic version of atomic64
implement, it may cause an extra save/restore of the interrupt
flag. So it's a tradeoff.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/staging/zram/zram_drv.c b/drivers/staging/zram/zram_drv.c
index 4b30fe5..ec2b2b5 100644
--- a/drivers/staging/zram/zram_drv.c
+++ b/drivers/staging/zram/zram_drv.c
@@ -42,25 +42,6 @@
/* Module params (documentation at end) */
static unsigned int num_devices = 1;
-static void zram_stat64_add(struct zram *zram, u64 *v, u64 inc)
-{
- spin_lock(&zram->stat64_lock);
- *v = *v + inc;
- spin_unlock(&zram->stat64_lock);
-}
-
-static void zram_stat64_sub(struct zram *zram, u64 *v, u64 dec)
-{
- spin_lock(&zram->stat64_lock);
- *v = *v - dec;
- spin_unlock(&zram->stat64_lock);
-}
-
-static void zram_stat64_inc(struct zram *zram, u64 *v)
-{
- zram_stat64_add(zram, v, 1);
-}
-
static int zram_test_flag(struct zram_meta *meta, u32 index,
enum zram_pageflags flag)
{
@@ -120,8 +101,7 @@
if (size <= PAGE_SIZE / 2)
zram->stats.good_compress--;
- zram_stat64_sub(zram, &zram->stats.compr_size,
- meta->table[index].size);
+ atomic64_sub(meta->table[index].size, &zram->stats.compr_size);
zram->stats.pages_stored--;
meta->table[index].handle = 0;
@@ -172,7 +152,7 @@
/* Should NEVER happen. Return bio error if it does. */
if (unlikely(ret != LZO_E_OK)) {
pr_err("Decompression failed! err=%d, page=%u\n", ret, index);
- zram_stat64_inc(zram, &zram->stats.failed_reads);
+ atomic64_inc(&zram->stats.failed_reads);
return ret;
}
@@ -326,7 +306,7 @@
meta->table[index].size = clen;
/* Update stats */
- zram_stat64_add(zram, &zram->stats.compr_size, clen);
+ atomic64_add(clen, &zram->stats.compr_size);
zram->stats.pages_stored++;
if (clen <= PAGE_SIZE / 2)
zram->stats.good_compress++;
@@ -336,7 +316,7 @@
kfree(uncmem);
if (ret)
- zram_stat64_inc(zram, &zram->stats.failed_writes);
+ atomic64_inc(&zram->stats.failed_writes);
return ret;
}
@@ -373,10 +353,10 @@
switch (rw) {
case READ:
- zram_stat64_inc(zram, &zram->stats.num_reads);
+ atomic64_inc(&zram->stats.num_reads);
break;
case WRITE:
- zram_stat64_inc(zram, &zram->stats.num_writes);
+ atomic64_inc(&zram->stats.num_writes);
break;
}
@@ -456,7 +436,7 @@
goto error;
if (!valid_io_request(zram, bio)) {
- zram_stat64_inc(zram, &zram->stats.invalid_io);
+ atomic64_inc(&zram->stats.invalid_io);
goto error;
}
@@ -595,7 +575,7 @@
down_write(&zram->lock);
zram_free_page(zram, index);
up_write(&zram->lock);
- zram_stat64_inc(zram, &zram->stats.notify_free);
+ atomic64_inc(&zram->stats.notify_free);
}
static const struct block_device_operations zram_devops = {
@@ -609,7 +589,6 @@
init_rwsem(&zram->lock);
init_rwsem(&zram->init_lock);
- spin_lock_init(&zram->stat64_lock);
zram->queue = blk_alloc_queue(GFP_KERNEL);
if (!zram->queue) {