diff --git a/include/linux/blktrace_api.h b/include/linux/blktrace_api.h
index 3b6ff5902edc..ea9da15d32d9 100644
--- a/include/linux/blktrace_api.h
+++ b/include/linux/blktrace_api.h
@@ -120,7 +120,9 @@ struct compat_blk_user_trace_setup {
 
 #endif
 
-extern void blk_fill_rwbs(char *rwbs, unsigned int op, int bytes);
+#define BLK_RWBS_LEN	8
+
+extern void blk_fill_rwbs(char *rwbs, unsigned int op);
 
 static inline sector_t blk_rq_trace_sector(struct request *rq)
 {
diff --git a/include/trace/events/bcache.h b/include/trace/events/bcache.h
index 0bddea663b3b..7440d704c200 100644
--- a/include/trace/events/bcache.h
+++ b/include/trace/events/bcache.h
@@ -18,7 +18,7 @@ DECLARE_EVENT_CLASS(bcache_request,
 		__field(sector_t,	sector			)
 		__field(dev_t,		orig_sector		)
 		__field(unsigned int,	nr_sector		)
-		__array(char,		rwbs,	6		)
+		__array(char,		rwbs,	BLK_RWBS_LEN	)
 	),
 
 	TP_fast_assign(
@@ -28,7 +28,7 @@ DECLARE_EVENT_CLASS(bcache_request,
 		__entry->sector		= bio->bi_iter.bi_sector;
 		__entry->orig_sector	= bio->bi_iter.bi_sector - 16;
 		__entry->nr_sector	= bio->bi_iter.bi_size >> 9;
-		blk_fill_rwbs(__entry->rwbs, bio->bi_opf, bio->bi_iter.bi_size);
+		blk_fill_rwbs(__entry->rwbs, bio->bi_opf);
 	),
 
 	TP_printk("%d,%d %s %llu + %u (from %d,%d @ %llu)",
@@ -95,14 +95,14 @@ DECLARE_EVENT_CLASS(bcache_bio,
 		__field(dev_t,		dev			)
 		__field(sector_t,	sector			)
 		__field(unsigned int,	nr_sector		)
-		__array(char,		rwbs,	6		)
+		__array(char,		rwbs,	BLK_RWBS_LEN	)
 	),
 
 	TP_fast_assign(
 		__entry->dev		= bio_dev(bio);
 		__entry->sector		= bio->bi_iter.bi_sector;
 		__entry->nr_sector	= bio->bi_iter.bi_size >> 9;
-		blk_fill_rwbs(__entry->rwbs, bio->bi_opf, bio->bi_iter.bi_size);
+		blk_fill_rwbs(__entry->rwbs, bio->bi_opf);
 	),
 
 	TP_printk("%d,%d  %s %llu + %u",
@@ -128,7 +128,7 @@ TRACE_EVENT(bcache_read,
 		__field(dev_t,		dev			)
 		__field(sector_t,	sector			)
 		__field(unsigned int,	nr_sector		)
-		__array(char,		rwbs,	6		)
+		__array(char,		rwbs,	BLK_RWBS_LEN	)
 		__field(bool,		cache_hit		)
 		__field(bool,		bypass			)
 	),
@@ -137,7 +137,7 @@ TRACE_EVENT(bcache_read,
 		__entry->dev		= bio_dev(bio);
 		__entry->sector		= bio->bi_iter.bi_sector;
 		__entry->nr_sector	= bio->bi_iter.bi_size >> 9;
-		blk_fill_rwbs(__entry->rwbs, bio->bi_opf, bio->bi_iter.bi_size);
+		blk_fill_rwbs(__entry->rwbs, bio->bi_opf);
 		__entry->cache_hit = hit;
 		__entry->bypass = bypass;
 	),
@@ -158,7 +158,7 @@ TRACE_EVENT(bcache_write,
 		__field(u64,		inode			)
 		__field(sector_t,	sector			)
 		__field(unsigned int,	nr_sector		)
-		__array(char,		rwbs,	6		)
+		__array(char,		rwbs,	BLK_RWBS_LEN	)
 		__field(bool,		writeback		)
 		__field(bool,		bypass			)
 	),
@@ -168,7 +168,7 @@ TRACE_EVENT(bcache_write,
 		__entry->inode		= inode;
 		__entry->sector		= bio->bi_iter.bi_sector;
 		__entry->nr_sector	= bio->bi_iter.bi_size >> 9;
-		blk_fill_rwbs(__entry->rwbs, bio->bi_opf, bio->bi_iter.bi_size);
+		blk_fill_rwbs(__entry->rwbs, bio->bi_opf);
 		__entry->writeback = writeback;
 		__entry->bypass = bypass;
 	),
@@ -229,7 +229,7 @@ TRACE_EVENT(bcache_journal_write,
 		__field(dev_t,		dev			)
 		__field(sector_t,	sector			)
 		__field(unsigned int,	nr_sector		)
-		__array(char,		rwbs,	6		)
+		__array(char,		rwbs,	BLK_RWBS_LEN	)
 		__field(u32,		nr_keys			)
 	),
 
@@ -238,7 +238,7 @@ TRACE_EVENT(bcache_journal_write,
 		__entry->sector		= bio->bi_iter.bi_sector;
 		__entry->nr_sector	= bio->bi_iter.bi_size >> 9;
 		__entry->nr_keys	= keys;
-		blk_fill_rwbs(__entry->rwbs, bio->bi_opf, bio->bi_iter.bi_size);
+		blk_fill_rwbs(__entry->rwbs, bio->bi_opf);
 	),
 
 	TP_printk("%d,%d  %s %llu + %u keys %u",
diff --git a/include/trace/events/block.h b/include/trace/events/block.h
index 81b43f5bdf23..aac9a5c0e2cc 100644
--- a/include/trace/events/block.h
+++ b/include/trace/events/block.h
@@ -10,7 +10,6 @@
 #include <linux/buffer_head.h>
 #include <linux/tracepoint.h>
 
-#define RWBS_LEN	8
 
 DECLARE_EVENT_CLASS(block_buffer,
 
@@ -81,7 +80,7 @@ TRACE_EVENT(block_rq_requeue,
 		__field(  dev_t,	dev			)
 		__field(  sector_t,	sector			)
 		__field(  unsigned int,	nr_sector		)
-		__array(  char,		rwbs,	RWBS_LEN	)
+		__array(  char,		rwbs,	BLK_RWBS_LEN	)
 		__dynamic_array( char,	cmd,	1		)
 	),
 
@@ -90,7 +89,7 @@ TRACE_EVENT(block_rq_requeue,
 		__entry->sector    = blk_rq_trace_sector(rq);
 		__entry->nr_sector = blk_rq_trace_nr_sectors(rq);
 
-		blk_fill_rwbs(__entry->rwbs, rq->cmd_flags, blk_rq_bytes(rq));
+		blk_fill_rwbs(__entry->rwbs, rq->cmd_flags);
 		__get_str(cmd)[0] = '\0';
 	),
 
@@ -124,7 +123,7 @@ TRACE_EVENT(block_rq_complete,
 		__field(  sector_t,	sector			)
 		__field(  unsigned int,	nr_sector		)
 		__field(  int,		error			)
-		__array(  char,		rwbs,	RWBS_LEN	)
+		__array(  char,		rwbs,	BLK_RWBS_LEN	)
 		__dynamic_array( char,	cmd,	1		)
 	),
 
@@ -134,7 +133,7 @@ TRACE_EVENT(block_rq_complete,
 		__entry->nr_sector = nr_bytes >> 9;
 		__entry->error     = error;
 
-		blk_fill_rwbs(__entry->rwbs, rq->cmd_flags, nr_bytes);
+		blk_fill_rwbs(__entry->rwbs, rq->cmd_flags);
 		__get_str(cmd)[0] = '\0';
 	),
 
@@ -156,7 +155,7 @@ DECLARE_EVENT_CLASS(block_rq,
 		__field(  sector_t,	sector			)
 		__field(  unsigned int,	nr_sector		)
 		__field(  unsigned int,	bytes			)
-		__array(  char,		rwbs,	RWBS_LEN	)
+		__array(  char,		rwbs,	BLK_RWBS_LEN	)
 		__array(  char,         comm,   TASK_COMM_LEN   )
 		__dynamic_array( char,	cmd,	1		)
 	),
@@ -167,7 +166,7 @@ DECLARE_EVENT_CLASS(block_rq,
 		__entry->nr_sector = blk_rq_trace_nr_sectors(rq);
 		__entry->bytes     = blk_rq_bytes(rq);
 
-		blk_fill_rwbs(__entry->rwbs, rq->cmd_flags, blk_rq_bytes(rq));
+		blk_fill_rwbs(__entry->rwbs, rq->cmd_flags);
 		__get_str(cmd)[0] = '\0';
 		memcpy(__entry->comm, current->comm, TASK_COMM_LEN);
 	),
@@ -232,7 +231,7 @@ TRACE_EVENT(block_bio_bounce,
 		__field( dev_t,		dev			)
 		__field( sector_t,	sector			)
 		__field( unsigned int,	nr_sector		)
-		__array( char,		rwbs,	RWBS_LEN	)
+		__array( char,		rwbs,	BLK_RWBS_LEN	)
 		__array( char,		comm,	TASK_COMM_LEN	)
 	),
 
@@ -240,7 +239,7 @@ TRACE_EVENT(block_bio_bounce,
 		__entry->dev		= bio_dev(bio);
 		__entry->sector		= bio->bi_iter.bi_sector;
 		__entry->nr_sector	= bio_sectors(bio);
-		blk_fill_rwbs(__entry->rwbs, bio->bi_opf, bio->bi_iter.bi_size);
+		blk_fill_rwbs(__entry->rwbs, bio->bi_opf);
 		memcpy(__entry->comm, current->comm, TASK_COMM_LEN);
 	),
 
@@ -266,11 +265,11 @@ TRACE_EVENT(block_bio_complete,
 	TP_ARGS(q, bio, error),
 
 	TP_STRUCT__entry(
-		__field( dev_t,		dev		)
-		__field( sector_t,	sector		)
-		__field( unsigned,	nr_sector	)
-		__field( int,		error		)
-		__array( char,		rwbs,	RWBS_LEN)
+		__field( dev_t,		dev			)
+		__field( sector_t,	sector			)
+		__field( unsigned,	nr_sector		)
+		__field( int,		error			)
+		__array( char,		rwbs,	BLK_RWBS_LEN	)
 	),
 
 	TP_fast_assign(
@@ -278,7 +277,7 @@ TRACE_EVENT(block_bio_complete,
 		__entry->sector		= bio->bi_iter.bi_sector;
 		__entry->nr_sector	= bio_sectors(bio);
 		__entry->error		= error;
-		blk_fill_rwbs(__entry->rwbs, bio->bi_opf, bio->bi_iter.bi_size);
+		blk_fill_rwbs(__entry->rwbs, bio->bi_opf);
 	),
 
 	TP_printk("%d,%d %s %llu + %u [%d]",
@@ -297,7 +296,7 @@ DECLARE_EVENT_CLASS(block_bio_merge,
 		__field( dev_t,		dev			)
 		__field( sector_t,	sector			)
 		__field( unsigned int,	nr_sector		)
-		__array( char,		rwbs,	RWBS_LEN	)
+		__array( char,		rwbs,	BLK_RWBS_LEN	)
 		__array( char,		comm,	TASK_COMM_LEN	)
 	),
 
@@ -305,7 +304,7 @@ DECLARE_EVENT_CLASS(block_bio_merge,
 		__entry->dev		= bio_dev(bio);
 		__entry->sector		= bio->bi_iter.bi_sector;
 		__entry->nr_sector	= bio_sectors(bio);
-		blk_fill_rwbs(__entry->rwbs, bio->bi_opf, bio->bi_iter.bi_size);
+		blk_fill_rwbs(__entry->rwbs, bio->bi_opf);
 		memcpy(__entry->comm, current->comm, TASK_COMM_LEN);
 	),
 
@@ -364,7 +363,7 @@ TRACE_EVENT(block_bio_queue,
 		__field( dev_t,		dev			)
 		__field( sector_t,	sector			)
 		__field( unsigned int,	nr_sector		)
-		__array( char,		rwbs,	RWBS_LEN	)
+		__array( char,		rwbs,	BLK_RWBS_LEN	)
 		__array( char,		comm,	TASK_COMM_LEN	)
 	),
 
@@ -372,7 +371,7 @@ TRACE_EVENT(block_bio_queue,
 		__entry->dev		= bio_dev(bio);
 		__entry->sector		= bio->bi_iter.bi_sector;
 		__entry->nr_sector	= bio_sectors(bio);
-		blk_fill_rwbs(__entry->rwbs, bio->bi_opf, bio->bi_iter.bi_size);
+		blk_fill_rwbs(__entry->rwbs, bio->bi_opf);
 		memcpy(__entry->comm, current->comm, TASK_COMM_LEN);
 	),
 
@@ -392,7 +391,7 @@ DECLARE_EVENT_CLASS(block_get_rq,
 		__field( dev_t,		dev			)
 		__field( sector_t,	sector			)
 		__field( unsigned int,	nr_sector		)
-		__array( char,		rwbs,	RWBS_LEN	)
+		__array( char,		rwbs,	BLK_RWBS_LEN	)
 		__array( char,		comm,	TASK_COMM_LEN	)
         ),
 
@@ -400,8 +399,7 @@ DECLARE_EVENT_CLASS(block_get_rq,
 		__entry->dev		= bio ? bio_dev(bio) : 0;
 		__entry->sector		= bio ? bio->bi_iter.bi_sector : 0;
 		__entry->nr_sector	= bio ? bio_sectors(bio) : 0;
-		blk_fill_rwbs(__entry->rwbs,
-			      bio ? bio->bi_opf : 0, __entry->nr_sector);
+		blk_fill_rwbs(__entry->rwbs, bio ? bio->bi_opf : 0);
 		memcpy(__entry->comm, current->comm, TASK_COMM_LEN);
         ),
 
@@ -524,18 +522,18 @@ TRACE_EVENT(block_split,
 	TP_ARGS(q, bio, new_sector),
 
 	TP_STRUCT__entry(
-		__field( dev_t,		dev				)
-		__field( sector_t,	sector				)
-		__field( sector_t,	new_sector			)
-		__array( char,		rwbs,		RWBS_LEN	)
-		__array( char,		comm,		TASK_COMM_LEN	)
+		__field( dev_t,		dev			)
+		__field( sector_t,	sector			)
+		__field( sector_t,	new_sector		)
+		__array( char,		rwbs,	BLK_RWBS_LEN	)
+		__array( char,		comm,	TASK_COMM_LEN	)
 	),
 
 	TP_fast_assign(
 		__entry->dev		= bio_dev(bio);
 		__entry->sector		= bio->bi_iter.bi_sector;
 		__entry->new_sector	= new_sector;
-		blk_fill_rwbs(__entry->rwbs, bio->bi_opf, bio->bi_iter.bi_size);
+		blk_fill_rwbs(__entry->rwbs, bio->bi_opf);
 		memcpy(__entry->comm, current->comm, TASK_COMM_LEN);
 	),
 
@@ -564,12 +562,12 @@ TRACE_EVENT(block_bio_remap,
 	TP_ARGS(q, bio, dev, from),
 
 	TP_STRUCT__entry(
-		__field( dev_t,		dev		)
-		__field( sector_t,	sector		)
-		__field( unsigned int,	nr_sector	)
-		__field( dev_t,		old_dev		)
-		__field( sector_t,	old_sector	)
-		__array( char,		rwbs,	RWBS_LEN)
+		__field( dev_t,		dev			)
+		__field( sector_t,	sector			)
+		__field( unsigned int,	nr_sector		)
+		__field( dev_t,		old_dev			)
+		__field( sector_t,	old_sector		)
+		__array( char,		rwbs,	BLK_RWBS_LEN	)
 	),
 
 	TP_fast_assign(
@@ -578,7 +576,7 @@ TRACE_EVENT(block_bio_remap,
 		__entry->nr_sector	= bio_sectors(bio);
 		__entry->old_dev	= dev;
 		__entry->old_sector	= from;
-		blk_fill_rwbs(__entry->rwbs, bio->bi_opf, bio->bi_iter.bi_size);
+		blk_fill_rwbs(__entry->rwbs, bio->bi_opf);
 	),
 
 	TP_printk("%d,%d %s %llu + %u <- (%d,%d) %llu",
@@ -608,13 +606,13 @@ TRACE_EVENT(block_rq_remap,
 	TP_ARGS(q, rq, dev, from),
 
 	TP_STRUCT__entry(
-		__field( dev_t,		dev		)
-		__field( sector_t,	sector		)
-		__field( unsigned int,	nr_sector	)
-		__field( dev_t,		old_dev		)
-		__field( sector_t,	old_sector	)
-		__field( unsigned int,	nr_bios		)
-		__array( char,		rwbs,	RWBS_LEN)
+		__field( dev_t,		dev			)
+		__field( sector_t,	sector			)
+		__field( unsigned int,	nr_sector		)
+		__field( dev_t,		old_dev			)
+		__field( sector_t,	old_sector		)
+		__field( unsigned int,	nr_bios			)
+		__array( char,		rwbs,	BLK_RWBS_LEN	)
 	),
 
 	TP_fast_assign(
@@ -624,7 +622,7 @@ TRACE_EVENT(block_rq_remap,
 		__entry->old_dev	= dev;
 		__entry->old_sector	= from;
 		__entry->nr_bios	= blk_rq_count_bios(rq);
-		blk_fill_rwbs(__entry->rwbs, rq->cmd_flags, blk_rq_bytes(rq));
+		blk_fill_rwbs(__entry->rwbs, rq->cmd_flags);
 	),
 
 	TP_printk("%d,%d %s %llu + %u <- (%d,%d) %llu %u",
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index ca39dc3230cb..dd10667d4164 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -1935,7 +1935,7 @@ void blk_trace_remove_sysfs(struct device *dev)
 
 #ifdef CONFIG_EVENT_TRACING
 
-void blk_fill_rwbs(char *rwbs, unsigned int op, int bytes)
+void blk_fill_rwbs(char *rwbs, unsigned int op)
 {
 	int i = 0;
 
