[PATCH] io-accounting: read accounting

Wire up read accounting for block devices, within submit_bio().

Cc: Jay Lan <jlan@sgi.com>
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Chris Sturtivant <csturtiv@sgi.com>
Cc: Tony Ernst <tee@sgi.com>
Cc: Guillaume Thouvenin <guillaume.thouvenin@bull.net>
Cc: David Wright <daw@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

block/ll_rw_blk.c

@@ -25,6 +25,7 @@
 #include <linux/slab.h>
 #include <linux/swap.h>
 #include <linux/writeback.h>
+#include <linux/task_io_accounting_ops.h>
 #include <linux/interrupt.h>
 #include <linux/cpu.h>
 #include <linux/blktrace_api.h>
@@ -3235,10 +3236,12 @@ void submit_bio(int rw, struct bio *bio)
 	BIO_BUG_ON(!bio->bi_size);
 	BIO_BUG_ON(!bio->bi_io_vec);
 	bio->bi_rw |= rw;
-	if (rw & WRITE)
+	if (rw & WRITE) {
 		count_vm_events(PGPGOUT, count);
-	else
+	} else {
+		task_io_account_read(bio->bi_size);
 		count_vm_events(PGPGIN, count);
+	}
 
 	if (unlikely(block_dump)) {
 		char b[BDEVNAME_SIZE];