[PATCH] Allow file systems to differentiate between data and meta reads

We can use this information for making more intelligent priority decisions, and it will also be useful for blktrace. Signed-off-by: Jens Axboe <axboe@suse.de>

[PATCH] Allow file systems to differentiate between data and meta reads
We can use this information for making more intelligent priority decisions, and it will also be useful for blktrace. Signed-off-by: Jens Axboe <axboe@suse.de>
Jens Axboe · Jens Axboe
1 parent da20a20f3b
Showing 4 changed files with 8 additions and 0 deletions Side-by-side Diff
block/ll_rw_blk.c
include/linux/bio.h
include/linux/blkdev.h
include/linux/fs.h
@@ -2884,6 +2884,8 @@
  
 	if (bio_sync(bio))
 		req->cmd_flags |= REQ_RW_SYNC;
+	if (bio_rw_meta(bio))
+		req->cmd_flags |= REQ_RW_META;
  
 	req->errors = 0;
 	req->hard_sector = req->sector = bio->bi_sector;
@@ -148,6 +148,7 @@
 #define BIO_RW_BARRIER	2
 #define BIO_RW_FAILFAST	3
 #define BIO_RW_SYNC	4
+#define BIO_RW_META	5
  
 /*
  * upper 16 bits of bi_rw define the io priority of this bio
@@ -178,6 +179,7 @@
 #define bio_sync(bio)		((bio)->bi_rw & (1 << BIO_RW_SYNC))
 #define bio_failfast(bio)	((bio)->bi_rw & (1 << BIO_RW_FAILFAST))
 #define bio_rw_ahead(bio)	((bio)->bi_rw & (1 << BIO_RW_AHEAD))
+#define bio_rw_meta(bio)	((bio)->bi_rw & (1 << BIO_RW_META))
  
 /*
  * will die
@@ -180,6 +180,7 @@
 	__REQ_ORDERED_COLOR,	/* is before or after barrier */
 	__REQ_RW_SYNC,		/* request is sync (O_DIRECT) */
 	__REQ_ALLOCED,		/* request came from our alloc pool */
+	__REQ_RW_META,		/* metadata io request */
 	__REQ_NR_BITS,		/* stops here */
 };
  
@@ -200,6 +201,7 @@
 #define REQ_ORDERED_COLOR	(1 << __REQ_ORDERED_COLOR)
 #define REQ_RW_SYNC	(1 << __REQ_RW_SYNC)
 #define REQ_ALLOCED	(1 << __REQ_ALLOCED)
+#define REQ_RW_META	(1 << __REQ_RW_META)
  
 #define BLK_MAX_CDB	16
  
@@ -543,6 +545,7 @@
  * We regard a request as sync, if it's a READ or a SYNC write.
  */
 #define rq_is_sync(rq)		(rq_data_dir((rq)) == READ || (rq)->cmd_flags & REQ_RW_SYNC)
+#define rq_is_meta(rq)		((rq)->cmd_flags & REQ_RW_META)
  
 static inline int blk_queue_full(struct request_queue *q, int rw)
 {
@@ -80,6 +80,7 @@
 #define READA 2		/* read-ahead  - don't block if no resources */
 #define SWRITE 3	/* for ll_rw_block() - wait for buffer lock */
 #define READ_SYNC	(READ | (1 << BIO_RW_SYNC))
+#define READ_META	(READ | (1 << BIO_RW_META))
 #define WRITE_SYNC	(WRITE | (1 << BIO_RW_SYNC))
 #define WRITE_BARRIER	((1 << BIO_RW) | (1 << BIO_RW_BARRIER))
...	...	@@ -2884,6 +2884,8 @@
2884	2884
2885	2885	if (bio_sync(bio))
2886	2886	req->cmd_flags \|= REQ_RW_SYNC;
	2887	+ if (bio_rw_meta(bio))
	2888	+ req->cmd_flags \|= REQ_RW_META;
2887	2889
2888	2890	req->errors = 0;
2889	2891	req->hard_sector = req->sector = bio->bi_sector;
...	...	@@ -148,6 +148,7 @@
148	148	#define BIO_RW_BARRIER 2
149	149	#define BIO_RW_FAILFAST 3
150	150	#define BIO_RW_SYNC 4
	151	+#define BIO_RW_META 5
151	152
152	153	/*
153	154	* upper 16 bits of bi_rw define the io priority of this bio
...	...	@@ -178,6 +179,7 @@
178	179	#define bio_sync(bio) ((bio)->bi_rw & (1 << BIO_RW_SYNC))
179	180	#define bio_failfast(bio) ((bio)->bi_rw & (1 << BIO_RW_FAILFAST))
180	181	#define bio_rw_ahead(bio) ((bio)->bi_rw & (1 << BIO_RW_AHEAD))
	182	+#define bio_rw_meta(bio) ((bio)->bi_rw & (1 << BIO_RW_META))
181	183
182	184	/*
183	185	* will die
...	...	@@ -180,6 +180,7 @@
180	180	__REQ_ORDERED_COLOR, /* is before or after barrier */
181	181	__REQ_RW_SYNC, /* request is sync (O_DIRECT) */
182	182	__REQ_ALLOCED, /* request came from our alloc pool */
	183	+ __REQ_RW_META, /* metadata io request */
183	184	__REQ_NR_BITS, /* stops here */
184	185	};
185	186
...	...	@@ -200,6 +201,7 @@
200	201	#define REQ_ORDERED_COLOR (1 << __REQ_ORDERED_COLOR)
201	202	#define REQ_RW_SYNC (1 << __REQ_RW_SYNC)
202	203	#define REQ_ALLOCED (1 << __REQ_ALLOCED)
	204	+#define REQ_RW_META (1 << __REQ_RW_META)
203	205
204	206	#define BLK_MAX_CDB 16
205	207
...	...	@@ -543,6 +545,7 @@
543	545	* We regard a request as sync, if it's a READ or a SYNC write.
544	546	*/
545	547	#define rq_is_sync(rq) (rq_data_dir((rq)) == READ \|\| (rq)->cmd_flags & REQ_RW_SYNC)
	548	+#define rq_is_meta(rq) ((rq)->cmd_flags & REQ_RW_META)
546	549
547	550	static inline int blk_queue_full(struct request_queue *q, int rw)
548	551	{
...	...	@@ -80,6 +80,7 @@
80	80	#define READA 2 /* read-ahead - don't block if no resources */
81	81	#define SWRITE 3 /* for ll_rw_block() - wait for buffer lock */
82	82	#define READ_SYNC (READ \| (1 << BIO_RW_SYNC))
	83	+#define READ_META (READ \| (1 << BIO_RW_META))
83	84	#define WRITE_SYNC (WRITE \| (1 << BIO_RW_SYNC))
84	85	#define WRITE_BARRIER ((1 << BIO_RW) \| (1 << BIO_RW_BARRIER))
85	86