[PATCH linux-next] zram: use sysfs_emit() to instead of scnprintf()

yang.yang29@zte.com.cn posted 1 patch 3 years, 5 months ago
There is a newer version of this series
drivers/block/zram/zram_drv.c | 25 ++++++++++---------------
1 file changed, 10 insertions(+), 15 deletions(-)
[PATCH linux-next] zram: use sysfs_emit() to instead of scnprintf()
Posted by yang.yang29@zte.com.cn 3 years, 5 months ago
From: Xu Panda <xu.panda@zte.com.cn>

Replace the open-code with sysfs_emit() to simplify the code.

Signed-off-by: Xu Panda <xu.panda@zte.com.cn>
Signed-off-by: Yang Yang <yang.yang29@zte.com>
---
 drivers/block/zram/zram_drv.c | 25 ++++++++++---------------
 1 file changed, 10 insertions(+), 15 deletions(-)

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 171eccc2249d..67aeb668f623 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -255,7 +255,7 @@ static ssize_t initstate_show(struct device *dev,
 	val = init_done(zram);
 	up_read(&zram->init_lock);

-	return scnprintf(buf, PAGE_SIZE, "%u\n", val);
+	return sysfs_emit(buf, "%u\n", val);
 }

 static ssize_t disksize_show(struct device *dev,
@@ -263,7 +263,7 @@ static ssize_t disksize_show(struct device *dev,
 {
 	struct zram *zram = dev_to_zram(dev);

-	return scnprintf(buf, PAGE_SIZE, "%llu\n", zram->disksize);
+	return sysfs_emit(buf, "%llu\n", zram->disksize);
 }

 static ssize_t mem_limit_store(struct device *dev,
@@ -404,7 +404,7 @@ static ssize_t writeback_limit_enable_show(struct device *dev,
 	spin_unlock(&zram->wb_limit_lock);
 	up_read(&zram->init_lock);

-	return scnprintf(buf, PAGE_SIZE, "%d\n", val);
+	return sysfs_emit(buf, "%d\n", val);
 }

 static ssize_t writeback_limit_store(struct device *dev,
@@ -439,7 +439,7 @@ static ssize_t writeback_limit_show(struct device *dev,
 	spin_unlock(&zram->wb_limit_lock);
 	up_read(&zram->init_lock);

-	return scnprintf(buf, PAGE_SIZE, "%llu\n", val);
+	return sysfs_emit(buf, "%llu\n", val);
 }

 static void reset_bdev(struct zram *zram)
@@ -1020,7 +1020,7 @@ static void zram_debugfs_unregister(struct zram *zram) {};
 static ssize_t max_comp_streams_show(struct device *dev,
 		struct device_attribute *attr, char *buf)
 {
-	return scnprintf(buf, PAGE_SIZE, "%d\n", num_online_cpus());
+	return sysfs_emit(buf, "%d\n", num_online_cpus());
 }

 static ssize_t max_comp_streams_store(struct device *dev,
@@ -1191,8 +1191,7 @@ static ssize_t io_stat_show(struct device *dev,
 	ssize_t ret;

 	down_read(&zram->init_lock);
-	ret = scnprintf(buf, PAGE_SIZE,
-			"%8llu %8llu %8llu %8llu\n",
+	ret = sysfs_emit(buf, "%8llu %8llu %8llu %8llu\n",
 			(u64)atomic64_read(&zram->stats.failed_reads),
 			(u64)atomic64_read(&zram->stats.failed_writes),
 			(u64)atomic64_read(&zram->stats.invalid_io),
@@ -1222,8 +1221,7 @@ static ssize_t mm_stat_show(struct device *dev,
 	orig_size = atomic64_read(&zram->stats.pages_stored);
 	max_used = atomic_long_read(&zram->stats.max_used_pages);

-	ret = scnprintf(buf, PAGE_SIZE,
-			"%8llu %8llu %8llu %8lu %8ld %8llu %8lu %8llu %8llu\n",
+	ret = sysfs_emit(buf, "%8llu %8llu %8llu %8lu %8ld %8llu %8lu %8llu %8llu\n",
 			orig_size << PAGE_SHIFT,
 			(u64)atomic64_read(&zram->stats.compr_data_size),
 			mem_used << PAGE_SHIFT,
@@ -1247,8 +1245,7 @@ static ssize_t bd_stat_show(struct device *dev,
 	ssize_t ret;

 	down_read(&zram->init_lock);
-	ret = scnprintf(buf, PAGE_SIZE,
-		"%8llu %8llu %8llu\n",
+	ret = sysfs_emit(buf, "%8llu %8llu %8llu\n",
 			FOUR_K((u64)atomic64_read(&zram->stats.bd_count)),
 			FOUR_K((u64)atomic64_read(&zram->stats.bd_reads)),
 			FOUR_K((u64)atomic64_read(&zram->stats.bd_writes)));
@@ -1266,9 +1263,7 @@ static ssize_t debug_stat_show(struct device *dev,
 	ssize_t ret;

 	down_read(&zram->init_lock);
-	ret = scnprintf(buf, PAGE_SIZE,
-			"version: %d\n%8llu %8llu\n",
-			version,
+	ret = sysfs_emit(buf, "version: %d\n%8llu %8llu\n", version,
 			(u64)atomic64_read(&zram->stats.writestall),
 			(u64)atomic64_read(&zram->stats.miss_free));
 	up_read(&zram->init_lock);
@@ -2504,7 +2499,7 @@ static ssize_t hot_add_show(struct class *class,

 	if (ret < 0)
 		return ret;
-	return scnprintf(buf, PAGE_SIZE, "%d\n", ret);
+	return sysfs_emit(buf, "%d\n", ret);
 }
 static struct class_attribute class_attr_hot_add =
 	__ATTR(hot_add, 0400, hot_add_show, NULL);
-- 
2.15.2
Re: [PATCH linux-next] zram: use sysfs_emit() to instead of scnprintf()
Posted by Sergey Senozhatsky 3 years, 5 months ago
On (22/11/14 11:41), yang.yang29@zte.com.cn wrote:
[..]
>  static ssize_t max_comp_streams_store(struct device *dev,
> @@ -1191,8 +1191,7 @@ static ssize_t io_stat_show(struct device *dev,
>  	ssize_t ret;
> 
>  	down_read(&zram->init_lock);
> -	ret = scnprintf(buf, PAGE_SIZE,
> -			"%8llu %8llu %8llu %8llu\n",
> +	ret = sysfs_emit(buf, "%8llu %8llu %8llu %8llu\n",
>  			(u64)atomic64_read(&zram->stats.failed_reads),
>  			(u64)atomic64_read(&zram->stats.failed_writes),
>  			(u64)atomic64_read(&zram->stats.invalid_io),

sysfs_emit() params need to be realigned to match (.

> @@ -1222,8 +1221,7 @@ static ssize_t mm_stat_show(struct device *dev,
>  	orig_size = atomic64_read(&zram->stats.pages_stored);
>  	max_used = atomic_long_read(&zram->stats.max_used_pages);
> 
> -	ret = scnprintf(buf, PAGE_SIZE,
> -			"%8llu %8llu %8llu %8lu %8ld %8llu %8lu %8llu %8llu\n",
> +	ret = sysfs_emit(buf, "%8llu %8llu %8llu %8lu %8ld %8llu %8lu %8llu %8llu\n",
>  			orig_size << PAGE_SHIFT,
>  			(u64)atomic64_read(&zram->stats.compr_data_size),
>  			mem_used << PAGE_SHIFT,

Ditto.

> @@ -1247,8 +1245,7 @@ static ssize_t bd_stat_show(struct device *dev,
>  	ssize_t ret;
> 
>  	down_read(&zram->init_lock);
> -	ret = scnprintf(buf, PAGE_SIZE,
> -		"%8llu %8llu %8llu\n",
> +	ret = sysfs_emit(buf, "%8llu %8llu %8llu\n",
>  			FOUR_K((u64)atomic64_read(&zram->stats.bd_count)),
>  			FOUR_K((u64)atomic64_read(&zram->stats.bd_reads)),
>  			FOUR_K((u64)atomic64_read(&zram->stats.bd_writes)));

Ditto.

> @@ -1266,9 +1263,7 @@ static ssize_t debug_stat_show(struct device *dev,
>  	ssize_t ret;
> 
>  	down_read(&zram->init_lock);
> -	ret = scnprintf(buf, PAGE_SIZE,
> -			"version: %d\n%8llu %8llu\n",
> -			version,
> +	ret = sysfs_emit(buf, "version: %d\n%8llu %8llu\n", version,
>  			(u64)atomic64_read(&zram->stats.writestall),
>  			(u64)atomic64_read(&zram->stats.miss_free));

Ditto.

---

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 01ab32f2897e..430933b73c1b 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -1192,10 +1192,10 @@ static ssize_t io_stat_show(struct device *dev,
 
 	down_read(&zram->init_lock);
 	ret = sysfs_emit(buf, "%8llu %8llu %8llu %8llu\n",
-			(u64)atomic64_read(&zram->stats.failed_reads),
-			(u64)atomic64_read(&zram->stats.failed_writes),
-			(u64)atomic64_read(&zram->stats.invalid_io),
-			(u64)atomic64_read(&zram->stats.notify_free));
+			 (u64)atomic64_read(&zram->stats.failed_reads),
+			 (u64)atomic64_read(&zram->stats.failed_writes),
+			 (u64)atomic64_read(&zram->stats.invalid_io),
+			 (u64)atomic64_read(&zram->stats.notify_free));
 	up_read(&zram->init_lock);
 
 	return ret;
@@ -1222,15 +1222,15 @@ static ssize_t mm_stat_show(struct device *dev,
 	max_used = atomic_long_read(&zram->stats.max_used_pages);
 
 	ret = sysfs_emit(buf, "%8llu %8llu %8llu %8lu %8ld %8llu %8lu %8llu %8llu\n",
-			orig_size << PAGE_SHIFT,
-			(u64)atomic64_read(&zram->stats.compr_data_size),
-			mem_used << PAGE_SHIFT,
-			zram->limit_pages << PAGE_SHIFT,
-			max_used << PAGE_SHIFT,
-			(u64)atomic64_read(&zram->stats.same_pages),
-			atomic_long_read(&pool_stats.pages_compacted),
-			(u64)atomic64_read(&zram->stats.huge_pages),
-			(u64)atomic64_read(&zram->stats.huge_pages_since));
+			 orig_size << PAGE_SHIFT,
+			 (u64)atomic64_read(&zram->stats.compr_data_size),
+			 mem_used << PAGE_SHIFT,
+			 zram->limit_pages << PAGE_SHIFT,
+			 max_used << PAGE_SHIFT,
+			 (u64)atomic64_read(&zram->stats.same_pages),
+			 atomic_long_read(&pool_stats.pages_compacted),
+			 (u64)atomic64_read(&zram->stats.huge_pages),
+			 (u64)atomic64_read(&zram->stats.huge_pages_since));
 	up_read(&zram->init_lock);
 
 	return ret;
@@ -1246,9 +1246,9 @@ static ssize_t bd_stat_show(struct device *dev,
 
 	down_read(&zram->init_lock);
 	ret = sysfs_emit(buf, "%8llu %8llu %8llu\n",
-			FOUR_K((u64)atomic64_read(&zram->stats.bd_count)),
-			FOUR_K((u64)atomic64_read(&zram->stats.bd_reads)),
-			FOUR_K((u64)atomic64_read(&zram->stats.bd_writes)));
+			 FOUR_K((u64)atomic64_read(&zram->stats.bd_count)),
+			 FOUR_K((u64)atomic64_read(&zram->stats.bd_reads)),
+			 FOUR_K((u64)atomic64_read(&zram->stats.bd_writes)));
 	up_read(&zram->init_lock);
 
 	return ret;
@@ -1264,8 +1264,8 @@ static ssize_t debug_stat_show(struct device *dev,
 
 	down_read(&zram->init_lock);
 	ret = sysfs_emit(buf, "version: %d\n%8llu %8llu\n", version,
-			(u64)atomic64_read(&zram->stats.writestall),
-			(u64)atomic64_read(&zram->stats.miss_free));
+			 (u64)atomic64_read(&zram->stats.writestall),
+			 (u64)atomic64_read(&zram->stats.miss_free));
 	up_read(&zram->init_lock);
 
 	return ret;