From: NeilBrown <neilb@suse.com>
To: Shaohua Li <shli@kernel.org>
Cc: linux-raid@vger.kernel.org
Subject: [md PATCH 1/4] md: add block tracing for bio_remapping
Date: Mon, 14 Nov 2016 16:30:21 +1100 [thread overview]
Message-ID: <147910142095.27168.11356591734977480053.stgit@noble> (raw)
In-Reply-To: <147910131504.27168.6566119701315109161.stgit@noble>
The block tracing infrastructure (accessed with blktrace/blkparse)
supports the tracing of mapping bios from one device to another.
This is currently used when a bio in a partition is mapped to the
whole device, when bios are mapped by dm, and for mapping in md/raid5.
Other md personalities do not include this tracing yet, so add it.
When a read-error is detected we redirect the request to a different device.
This could justifiably be seen as a new mapping for the originial bio,
or a secondary mapping for the bio that errors. This patch uses
the second option.
When md is used under dm-raid, the mappings are not traced as we do
not have access to the block device number of the parent.
Signed-off-by: NeilBrown <neilb@suse.com>
---
drivers/md/linear.c | 8 +++++++-
drivers/md/raid0.c | 8 +++++++-
drivers/md/raid1.c | 33 ++++++++++++++++++++++++++++++---
drivers/md/raid10.c | 29 +++++++++++++++++++++++++++--
4 files changed, 71 insertions(+), 7 deletions(-)
diff --git a/drivers/md/linear.c b/drivers/md/linear.c
index 9c7d4f5483ea..8c0bccfa53a2 100644
--- a/drivers/md/linear.c
+++ b/drivers/md/linear.c
@@ -21,6 +21,7 @@
#include <linux/seq_file.h>
#include <linux/module.h>
#include <linux/slab.h>
+#include <trace/events/block.h>
#include "md.h"
#include "linear.h"
@@ -256,8 +257,13 @@ static void linear_make_request(struct mddev *mddev, struct bio *bio)
!blk_queue_discard(bdev_get_queue(split->bi_bdev)))) {
/* Just ignore it */
bio_endio(split);
- } else
+ } else {
+ if (mddev->gendisk)
+ trace_block_bio_remap(bdev_get_queue(split->bi_bdev),
+ split, disk_devt(mddev->gendisk),
+ bio->bi_iter.bi_sector);
generic_make_request(split);
+ }
} while (split != bio);
return;
diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c
index b3ba77a3c3bc..841b3ad0f5ff 100644
--- a/drivers/md/raid0.c
+++ b/drivers/md/raid0.c
@@ -21,6 +21,7 @@
#include <linux/seq_file.h>
#include <linux/module.h>
#include <linux/slab.h>
+#include <trace/events/block.h>
#include "md.h"
#include "raid0.h"
#include "raid5.h"
@@ -491,8 +492,13 @@ static void raid0_make_request(struct mddev *mddev, struct bio *bio)
!blk_queue_discard(bdev_get_queue(split->bi_bdev)))) {
/* Just ignore it */
bio_endio(split);
- } else
+ } else {
+ if (mddev->gendisk)
+ trace_block_bio_remap(bdev_get_queue(split->bi_bdev),
+ split, disk_devt(mddev->gendisk),
+ bio->bi_iter.bi_sector);
generic_make_request(split);
+ }
} while (split != bio);
}
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 9ac61cd85e5c..3710a792a149 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -37,6 +37,7 @@
#include <linux/module.h>
#include <linux/seq_file.h>
#include <linux/ratelimit.h>
+#include <trace/events/block.h>
#include "md.h"
#include "raid1.h"
#include "bitmap.h"
@@ -743,6 +744,7 @@ static void flush_pending_writes(struct r1conf *conf)
while (bio) { /* submit pending writes */
struct bio *next = bio->bi_next;
struct md_rdev *rdev = (void*)bio->bi_bdev;
+ struct r1bio *r1_bio = bio->bi_private;
bio->bi_next = NULL;
bio->bi_bdev = rdev->bdev;
if (test_bit(Faulty, &rdev->flags)) {
@@ -752,8 +754,13 @@ static void flush_pending_writes(struct r1conf *conf)
!blk_queue_discard(bdev_get_queue(bio->bi_bdev))))
/* Just ignore it */
bio_endio(bio);
- else
+ else {
+ if (conf->mddev->gendisk)
+ trace_block_bio_remap(bdev_get_queue(bio->bi_bdev),
+ bio, disk_devt(conf->mddev->gendisk),
+ r1_bio->sector);
generic_make_request(bio);
+ }
bio = next;
}
} else
@@ -1022,6 +1029,7 @@ static void raid1_unplug(struct blk_plug_cb *cb, bool from_schedule)
while (bio) { /* submit pending writes */
struct bio *next = bio->bi_next;
struct md_rdev *rdev = (void*)bio->bi_bdev;
+ struct r1bio *r1_bio = bio->bi_private;
bio->bi_next = NULL;
bio->bi_bdev = rdev->bdev;
if (test_bit(Faulty, &rdev->flags)) {
@@ -1031,8 +1039,13 @@ static void raid1_unplug(struct blk_plug_cb *cb, bool from_schedule)
!blk_queue_discard(bdev_get_queue(bio->bi_bdev))))
/* Just ignore it */
bio_endio(bio);
- else
+ else {
+ if (mddev->gendisk)
+ trace_block_bio_remap(bdev_get_queue(bio->bi_bdev),
+ bio, disk_devt(mddev->gendisk),
+ r1_bio->sector);
generic_make_request(bio);
+ }
bio = next;
}
kfree(plug);
@@ -1162,6 +1175,11 @@ static void raid1_make_request(struct mddev *mddev, struct bio * bio)
bio_set_op_attrs(read_bio, op, do_sync);
read_bio->bi_private = r1_bio;
+ if (mddev->gendisk)
+ trace_block_bio_remap(bdev_get_queue(read_bio->bi_bdev),
+ read_bio, disk_devt(mddev->gendisk),
+ r1_bio->sector);
+
if (max_sectors < r1_bio->sectors) {
/* could not read all from this device, so we will
* need another r1_bio.
@@ -2290,6 +2308,8 @@ static void handle_read_error(struct r1conf *conf, struct r1bio *r1_bio)
struct bio *bio;
char b[BDEVNAME_SIZE];
struct md_rdev *rdev;
+ dev_t bio_dev;
+ sector_t bio_sector;
clear_bit(R1BIO_ReadError, &r1_bio->state);
/* we got a read error. Maybe the drive is bad. Maybe just
@@ -2303,6 +2323,8 @@ static void handle_read_error(struct r1conf *conf, struct r1bio *r1_bio)
bio = r1_bio->bios[r1_bio->read_disk];
bdevname(bio->bi_bdev, b);
+ bio_dev = bio->bi_bdev->bd_dev;
+ bio_sector = conf->mirrors[r1_bio->read_disk].rdev->data_offset + r1_bio->sector;
bio_put(bio);
r1_bio->bios[r1_bio->read_disk] = NULL;
@@ -2353,6 +2375,8 @@ static void handle_read_error(struct r1conf *conf, struct r1bio *r1_bio)
else
mbio->bi_phys_segments++;
spin_unlock_irq(&conf->device_lock);
+ trace_block_bio_remap(bdev_get_queue(bio->bi_bdev),
+ bio, bio_dev, bio_sector);
generic_make_request(bio);
bio = NULL;
@@ -2367,8 +2391,11 @@ static void handle_read_error(struct r1conf *conf, struct r1bio *r1_bio)
sectors_handled;
goto read_more;
- } else
+ } else {
+ trace_block_bio_remap(bdev_get_queue(bio->bi_bdev),
+ bio, bio_dev, bio_sector);
generic_make_request(bio);
+ }
}
}
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 5290be3d5c26..d144c3425824 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -25,6 +25,7 @@
#include <linux/seq_file.h>
#include <linux/ratelimit.h>
#include <linux/kthread.h>
+#include <trace/events/block.h>
#include "md.h"
#include "raid10.h"
#include "raid0.h"
@@ -859,6 +860,7 @@ static void flush_pending_writes(struct r10conf *conf)
while (bio) { /* submit pending writes */
struct bio *next = bio->bi_next;
struct md_rdev *rdev = (void*)bio->bi_bdev;
+ struct r10bio *r10_bio = bio->bi_private;
bio->bi_next = NULL;
bio->bi_bdev = rdev->bdev;
if (test_bit(Faulty, &rdev->flags)) {
@@ -868,8 +870,13 @@ static void flush_pending_writes(struct r10conf *conf)
!blk_queue_discard(bdev_get_queue(bio->bi_bdev))))
/* Just ignore it */
bio_endio(bio);
- else
+ else {
+ if (conf->mddev->gendisk)
+ trace_block_bio_remap(bdev_get_queue(bio->bi_bdev),
+ bio, disk_devt(conf->mddev->gendisk),
+ r10_bio->sector);
generic_make_request(bio);
+ }
bio = next;
}
} else
@@ -1042,6 +1049,7 @@ static void raid10_unplug(struct blk_plug_cb *cb, bool from_schedule)
while (bio) { /* submit pending writes */
struct bio *next = bio->bi_next;
struct md_rdev *rdev = (void*)bio->bi_bdev;
+ struct r10bio *r10_bio = bio->bi_private;
bio->bi_next = NULL;
bio->bi_bdev = rdev->bdev;
if (test_bit(Faulty, &rdev->flags)) {
@@ -1051,8 +1059,13 @@ static void raid10_unplug(struct blk_plug_cb *cb, bool from_schedule)
!blk_queue_discard(bdev_get_queue(bio->bi_bdev))))
/* Just ignore it */
bio_endio(bio);
- else
+ else {
+ if (conf->mddev->gendisk)
+ trace_block_bio_remap(bdev_get_queue(bio->bi_bdev),
+ bio, disk_devt(conf->mddev->gendisk),
+ r10_bio->sector);
generic_make_request(bio);
+ }
bio = next;
}
kfree(plug);
@@ -1165,6 +1178,10 @@ static void __make_request(struct mddev *mddev, struct bio *bio)
bio_set_op_attrs(read_bio, op, do_sync);
read_bio->bi_private = r10_bio;
+ if (mddev->gendisk)
+ trace_block_bio_remap(bdev_get_queue(read_bio->bi_bdev),
+ read_bio, disk_devt(mddev->gendisk),
+ r10_bio->sector);
if (max_sectors < r10_bio->sectors) {
/* Could not read all from this device, so we will
* need another r10_bio.
@@ -2496,6 +2513,8 @@ static void handle_read_error(struct mddev *mddev, struct r10bio *r10_bio)
char b[BDEVNAME_SIZE];
unsigned long do_sync;
int max_sectors;
+ dev_t bio_dev;
+ sector_t bio_last_sector;
/* we got a read error. Maybe the drive is bad. Maybe just
* the block and we can fix it.
@@ -2507,6 +2526,8 @@ static void handle_read_error(struct mddev *mddev, struct r10bio *r10_bio)
*/
bio = r10_bio->devs[slot].bio;
bdevname(bio->bi_bdev, b);
+ bio_dev = bio->bi_bdev->bd_dev;
+ bio_last_sector = r10_bio->devs[slot].addr + rdev->data_offset + r10_bio->sectors;
bio_put(bio);
r10_bio->devs[slot].bio = NULL;
@@ -2546,6 +2567,10 @@ static void handle_read_error(struct mddev *mddev, struct r10bio *r10_bio)
bio_set_op_attrs(bio, REQ_OP_READ, do_sync);
bio->bi_private = r10_bio;
bio->bi_end_io = raid10_end_read_request;
+ trace_block_bio_remap(bdev_get_queue(bio->bi_bdev),
+ bio, bio_dev,
+ bio_last_sector - r10_bio->sectors);
+
if (max_sectors < r10_bio->sectors) {
/* Drat - have to split this up more */
struct bio *mbio = r10_bio->master_bio;
next prev parent reply other threads:[~2016-11-14 5:30 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-11-14 5:30 [md PATCH 0/4] Improve blktrace tracing of md NeilBrown
2016-11-14 5:30 ` [md PATCH 4/4] md/raid1, raid10: add blktrace records when IO is delayed NeilBrown
2016-11-14 5:30 ` [md PATCH 2/4] md: add bio completion tracing for raid1/raid10 NeilBrown
2016-11-16 14:32 ` Christoph Hellwig
2016-11-17 5:35 ` NeilBrown
2016-11-17 12:51 ` Christoph Hellwig
2016-11-14 5:30 ` [md PATCH 3/4] md/bitmap: add blktrace event for writes to the bitmap NeilBrown
2016-11-16 19:31 ` Shaohua Li
2016-11-14 5:30 ` NeilBrown [this message]
2016-11-16 19:29 ` [md PATCH 1/4] md: add block tracing for bio_remapping Shaohua Li
2016-11-17 5:33 ` NeilBrown
2016-11-17 18:04 ` Shaohua Li
2016-11-18 0:45 ` NeilBrown
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