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@xxxxxxxx>
---
This is the revised version based on discussions.
Now uses correct sector for linear and raid0, and code for raid1/raid10
rearranged a bit.
drivers/md/linear.c | 18 ++++++++++++------
drivers/md/raid0.c | 13 ++++++++++---
drivers/md/raid1.c | 26 ++++++++++++++++++++++++--
drivers/md/raid10.c | 29 +++++++++++++++++++++++++++--
4 files changed, 73 insertions(+), 13 deletions(-)
diff --git a/drivers/md/linear.c b/drivers/md/linear.c
index 9c7d4f5483ea..5975c9915684 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"
@@ -227,22 +228,22 @@ static void linear_make_request(struct mddev *mddev, struct bio *bio)
}
do {
- tmp_dev = which_dev(mddev, bio->bi_iter.bi_sector);
+ sector_t bio_sector = bio->bi_iter.bi_sector;
+ tmp_dev = which_dev(mddev, bio_sector);
start_sector = tmp_dev->end_sector - tmp_dev->rdev->sectors;
end_sector = tmp_dev->end_sector;
data_offset = tmp_dev->rdev->data_offset;
bio->bi_bdev = tmp_dev->rdev->bdev;
- if (unlikely(bio->bi_iter.bi_sector >= end_sector ||
- bio->bi_iter.bi_sector < start_sector))
+ if (unlikely(bio_sector >= end_sector ||
+ bio_sector < start_sector))
goto out_of_bounds;
if (unlikely(bio_end_sector(bio) > end_sector)) {
/* This bio crosses a device boundary, so we have to
* split it.
*/
- split = bio_split(bio, end_sector -
- bio->bi_iter.bi_sector,
+ split = bio_split(bio, end_sector - bio_sector,
GFP_NOIO, fs_bio_set);
bio_chain(split, bio);
} else {
@@ -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_sector);
generic_make_request(split);
+ }
} while (split != bio);
return;
diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c
index b3ba77a3c3bc..e628f187e5ad 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"
@@ -463,7 +464,8 @@ static void raid0_make_request(struct mddev *mddev, struct bio *bio)
}
do {
- sector_t sector = bio->bi_iter.bi_sector;
+ sector_t bio_sector = bio->bi_iter.bi_sector;
+ sector_t sector = bio_sector;
unsigned chunk_sects = mddev->chunk_sectors;
unsigned sectors = chunk_sects -
@@ -472,7 +474,7 @@ static void raid0_make_request(struct mddev *mddev, struct bio *bio)
: sector_div(sector, chunk_sects));
/* Restore due to sector_div */
- sector = bio->bi_iter.bi_sector;
+ sector = bio_sector;
if (sectors < bio_sectors(bio)) {
split = bio_split(bio, sectors, GFP_NOIO, fs_bio_set);
@@ -491,8 +493,13 @@ 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_sector);
generic_make_request(split);
+ }
} while (split != bio);
}
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 9ac61cd85e5c..2dc1934925ec 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"
@@ -1162,6 +1163,11 @@ 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.
@@ -1367,13 +1373,20 @@ static void raid1_make_request(struct mddev *mddev, struct bio * bio)
mbio->bi_iter.bi_sector = (r1_bio->sector +
conf->mirrors[i].rdev->data_offset);
- mbio->bi_bdev = (void*)conf->mirrors[i].rdev;
+ mbio->bi_bdev = conf->mirrors[i].rdev->bdev;
mbio->bi_end_io = raid1_end_write_request;
bio_set_op_attrs(mbio, op, do_flush_fua | do_sync);
mbio->bi_private = r1_bio;
atomic_inc(&r1_bio->remaining);
+ if (mddev->gendisk)
+ trace_block_bio_remap(bdev_get_queue(mbio->bi_bdev),
+ mbio, disk_devt(mddev->gendisk),
+ r1_bio->sector);
+ /* flush_pending_writes() needs access to the rdev so...*/
+ mbio->bi_bdev = (void*)conf->mirrors[i].rdev;
+
cb = blk_check_plugged(raid1_unplug, mddev, sizeof(*plug));
if (cb)
plug = container_of(cb, struct raid1_plug_cb, cb);
@@ -2290,6 +2303,8 @@ 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 +2318,8 @@ 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 +2370,8 @@ 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 +2386,11 @@ 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..c63041ec9415 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"
@@ -1165,6 +1166,10 @@ 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.
@@ -1367,11 +1372,17 @@ static void __make_request(struct mddev *mddev, struct bio *bio)
mbio->bi_iter.bi_sector = (r10_bio->devs[i].addr+
choose_data_offset(r10_bio,
rdev));
- mbio->bi_bdev = (void*)rdev;
+ mbio->bi_bdev = rdev->bdev;
mbio->bi_end_io = raid10_end_write_request;
bio_set_op_attrs(mbio, op, do_sync | do_fua);
mbio->bi_private = r10_bio;
+ if (conf->mddev->gendisk)
+ trace_block_bio_remap(bdev_get_queue(mbio->bi_bdev),
+ mbio, disk_devt(conf->mddev->gendisk),
+ r10_bio->sector);
+ mbio->bi_bdev = (void*)rdev;
+
atomic_inc(&r10_bio->remaining);
cb = blk_check_plugged(raid10_unplug, mddev,
@@ -1409,11 +1420,17 @@ static void __make_request(struct mddev *mddev, struct bio *bio)
mbio->bi_iter.bi_sector = (r10_bio->devs[i].addr +
choose_data_offset(
r10_bio, rdev));
- mbio->bi_bdev = (void*)rdev;
+ mbio->bi_bdev = rdev->bdev;
mbio->bi_end_io = raid10_end_write_request;
bio_set_op_attrs(mbio, op, do_sync | do_fua);
mbio->bi_private = r10_bio;
+ if (conf->mddev->gendisk)
+ trace_block_bio_remap(bdev_get_queue(mbio->bi_bdev),
+ mbio, disk_devt(conf->mddev->gendisk),
+ r10_bio->sector);
+ mbio->bi_bdev = (void*)rdev;
+
atomic_inc(&r10_bio->remaining);
spin_lock_irqsave(&conf->device_lock, flags);
bio_list_add(&conf->pending_bio_list, mbio);
@@ -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;
--
2.10.2
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