-----BEGIN PGP SIGNATURE-----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=qBae
-----END PGP SIGNATURE-----
Merge tag 'for-5.1/block-post-20190315' of git://git.kernel.dk/linux-block
Pull more block layer changes from Jens Axboe:
"This is a collection of both stragglers, and fixes that came in after
I finalized the initial pull. This contains:
- An MD pull request from Song, with a few minor fixes
- Set of NVMe patches via Christoph
- Pull request from Konrad, with a few fixes for xen/blkback
- pblk fix IO calculation fix (Javier)
- Segment calculation fix for pass-through (Ming)
- Fallthrough annotation for blkcg (Mathieu)"
* tag 'for-5.1/block-post-20190315' of git://git.kernel.dk/linux-block: (25 commits)
blkcg: annotate implicit fall through
nvme-tcp: support C2HData with SUCCESS flag
nvmet: ignore EOPNOTSUPP for discard
nvme: add proper write zeroes setup for the multipath device
nvme: add proper discard setup for the multipath device
nvme: remove nvme_ns_config_oncs
nvme: disable Write Zeroes for qemu controllers
nvmet-fc: bring Disconnect into compliance with FC-NVME spec
nvmet-fc: fix issues with targetport assoc_list list walking
nvme-fc: reject reconnect if io queue count is reduced to zero
nvme-fc: fix numa_node when dev is null
nvme-fc: use nr_phys_segments to determine existence of sgl
nvme-loop: init nvmet_ctrl fatal_err_work when allocate
nvme: update comment to make the code easier to read
nvme: put ns_head ref if namespace fails allocation
nvme-trace: fix cdw10 buffer overrun
nvme: don't warn on block content change effects
nvme: add get-feature to admin cmds tracer
md: Fix failed allocation of md_register_thread
It's wrong to add len to sector_nr in raid10 reshape twice
...
All users of VM_MAX_READAHEAD actually convert it to kbytes and then to
pages. Define the macro explicitly as (SZ_128K / PAGE_SIZE). This
simplifies the expression in every filesystem. Also rename the macro to
VM_READAHEAD_PAGES to properly convey its meaning. Finally remove unused
VM_MIN_READAHEAD
[akpm@linux-foundation.org: fix fs/io_uring.c, per Stephen]
Link: http://lkml.kernel.org/r/20181221144053.24318-1-nborisov@suse.com
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Cc: Dominique Martinet <asmadeus@codewreck.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is mostly update of the usual drivers: arcmsr, qla2xxx, lpfc,
hisi_sas, target/iscsi and target/core. Additionally Christoph
refactored gdth as part of the dma changes. The major mid-layer
change this time is the removal of bidi commands and with them the
whole of the osd/exofs driver and filesystem.
Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
-----BEGIN PGP SIGNATURE-----
iJwEABMIAEQWIQTnYEDbdso9F2cI+arnQslM7pishQUCXIC54SYcamFtZXMuYm90
dG9tbGV5QGhhbnNlbnBhcnRuZXJzaGlwLmNvbQAKCRDnQslM7pishT1GAPwJEV23
ExPiPsnuVgKj49nLTagZ3rILRQcYNbL+MNYqxQEA0cT8FHzSDBfWY5OKPNE+RQ8z
f69LpXGmMpuagKGvvd4=
=Fhy1
-----END PGP SIGNATURE-----
Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI updates from James Bottomley:
"This is mostly update of the usual drivers: arcmsr, qla2xxx, lpfc,
hisi_sas, target/iscsi and target/core.
Additionally Christoph refactored gdth as part of the dma changes. The
major mid-layer change this time is the removal of bidi commands and
with them the whole of the osd/exofs driver and filesystem. This is a
major simplification for block and mq in particular"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (240 commits)
scsi: cxgb4i: validate tcp sequence number only if chip version <= T5
scsi: cxgb4i: get pf number from lldi->pf
scsi: core: replace GFP_ATOMIC with GFP_KERNEL in scsi_scan.c
scsi: mpt3sas: Add missing breaks in switch statements
scsi: aacraid: Fix missing break in switch statement
scsi: kill command serial number
scsi: csiostor: drop serial_number usage
scsi: mvumi: use request tag instead of serial_number
scsi: dpt_i2o: remove serial number usage
scsi: st: osst: Remove negative constant left-shifts
scsi: ufs-bsg: Allow reading descriptors
scsi: ufs: Allow reading descriptor via raw upiu
scsi: ufs-bsg: Change the calling convention for write descriptor
scsi: ufs: Remove unused device quirks
Revert "scsi: ufs: disable vccq if it's not needed by UFS device"
scsi: megaraid_sas: Remove a bunch of set but not used variables
scsi: clean obsolete return values of eh_timed_out
scsi: sd: Optimal I/O size should be a multiple of physical block size
scsi: MAINTAINERS: SCSI initiator and target tweaks
scsi: fcoe: make use of fip_mode enum complete
...
-----BEGIN PGP SIGNATURE-----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=p78E
-----END PGP SIGNATURE-----
Merge tag 'io_uring-2019-03-06' of git://git.kernel.dk/linux-block
Pull io_uring IO interface from Jens Axboe:
"Second attempt at adding the io_uring interface.
Since the first one, we've added basic unit testing of the three
system calls, that resides in liburing like the other unit tests that
we have so far. It'll take a while to get full coverage of it, but
we're working towards it. I've also added two basic test programs to
tools/io_uring. One uses the raw interface and has support for all the
various features that io_uring supports outside of standard IO, like
fixed files, fixed IO buffers, and polled IO. The other uses the
liburing API, and is a simplified version of cp(1).
This adds support for a new IO interface, io_uring.
io_uring allows an application to communicate with the kernel through
two rings, the submission queue (SQ) and completion queue (CQ) ring.
This allows for very efficient handling of IOs, see the v5 posting for
some basic numbers:
https://lore.kernel.org/linux-block/20190116175003.17880-1-axboe@kernel.dk/
Outside of just efficiency, the interface is also flexible and
extendable, and allows for future use cases like the upcoming NVMe
key-value store API, networked IO, and so on. It also supports async
buffered IO, something that we've always failed to support in the
kernel.
Outside of basic IO features, it supports async polled IO as well.
This particular feature has already been tested at Facebook months ago
for flash storage boxes, with 25-33% improvements. It makes polled IO
actually useful for real world use cases, where even basic flash sees
a nice win in terms of efficiency, latency, and performance. These
boxes were IOPS bound before, now they are not.
This series adds three new system calls. One for setting up an
io_uring instance (io_uring_setup(2)), one for submitting/completing
IO (io_uring_enter(2)), and one for aux functions like registrating
file sets, buffers, etc (io_uring_register(2)). Through the help of
Arnd, I've coordinated the syscall numbers so merge on that front
should be painless.
Jon did a writeup of the interface a while back, which (except for
minor details that have been tweaked) is still accurate. Find that
here:
https://lwn.net/Articles/776703/
Huge thanks to Al Viro for helping getting the reference cycle code
correct, and to Jann Horn for his extensive reviews focused on both
security and bugs in general.
There's a userspace library that provides basic functionality for
applications that don't need or want to care about how to fiddle with
the rings directly. It has helpers to allow applications to easily set
up an io_uring instance, and submit/complete IO through it without
knowing about the intricacies of the rings. It also includes man pages
(thanks to Jeff Moyer), and will continue to grow support helper
functions and features as time progresses. Find it here:
git://git.kernel.dk/liburing
Fio has full support for the raw interface, both in the form of an IO
engine (io_uring), but also with a small test application (t/io_uring)
that can exercise and benchmark the interface"
* tag 'io_uring-2019-03-06' of git://git.kernel.dk/linux-block:
io_uring: add a few test tools
io_uring: allow workqueue item to handle multiple buffered requests
io_uring: add support for IORING_OP_POLL
io_uring: add io_kiocb ref count
io_uring: add submission polling
io_uring: add file set registration
net: split out functions related to registering inflight socket files
io_uring: add support for pre-mapped user IO buffers
block: implement bio helper to add iter bvec pages to bio
io_uring: batch io_kiocb allocation
io_uring: use fget/fput_many() for file references
fs: add fget_many() and fput_many()
io_uring: support for IO polling
io_uring: add fsync support
Add io_uring IO interface
-----BEGIN PGP SIGNATURE-----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=VBaU
-----END PGP SIGNATURE-----
Merge tag 'for-5.1/block-20190302' of git://git.kernel.dk/linux-block
Pull block layer updates from Jens Axboe:
"Not a huge amount of changes in this round, the biggest one is that we
finally have Mings multi-page bvec support merged. Apart from that,
this pull request contains:
- Small series that avoids quiescing the queue for sysfs changes that
match what we currently have (Aleksei)
- Series of bcache fixes (via Coly)
- Series of lightnvm fixes (via Mathias)
- NVMe pull request from Christoph. Nothing major, just SPDX/license
cleanups, RR mp policy (Hannes), and little fixes (Bart,
Chaitanya).
- BFQ series (Paolo)
- Save blk-mq cpu -> hw queue mapping, removing a pointer indirection
for the fast path (Jianchao)
- fops->iopoll() added for async IO polling, this is a feature that
the upcoming io_uring interface will use (Christoph, me)
- Partition scan loop fixes (Dongli)
- mtip32xx conversion from managed resource API (Christoph)
- cdrom registration race fix (Guenter)
- MD pull from Song, two minor fixes.
- Various documentation fixes (Marcos)
- Multi-page bvec feature. This brings a lot of nice improvements
with it, like more efficient splitting, larger IOs can be supported
without growing the bvec table size, and so on. (Ming)
- Various little fixes to core and drivers"
* tag 'for-5.1/block-20190302' of git://git.kernel.dk/linux-block: (117 commits)
block: fix updating bio's front segment size
block: Replace function name in string with __func__
nbd: propagate genlmsg_reply return code
floppy: remove set but not used variable 'q'
null_blk: fix checking for REQ_FUA
block: fix NULL pointer dereference in register_disk
fs: fix guard_bio_eod to check for real EOD errors
blk-mq: use HCTX_TYPE_DEFAULT but not 0 to index blk_mq_tag_set->map
block: optimize bvec iteration in bvec_iter_advance
block: introduce mp_bvec_for_each_page() for iterating over page
block: optimize blk_bio_segment_split for single-page bvec
block: optimize __blk_segment_map_sg() for single-page bvec
block: introduce bvec_nth_page()
iomap: wire up the iopoll method
block: add bio_set_polled() helper
block: wire up block device iopoll method
fs: add an iopoll method to struct file_operations
loop: set GENHD_FL_NO_PART_SCAN after blkdev_reread_part()
loop: do not print warn message if partition scan is successful
block: bounce: make sure that bvec table is updated
...
blk_recount_segments() can be called in bio_add_pc_page() for
calculating how many segments this bio will has after one page is added
to this bio. If the resulted segment number is beyond the queue limit,
the added page will be removed.
The try-and-fix policy requires blk_recount_segments(__blk_recalc_rq_segments)
to not consider the segment number limit. Unfortunately bvec_split_segs()
does check this limit, and causes small segment number returned to
bio_add_pc_page(), then page still may be added to the bio even though
segment number limit becomes broken.
Fixes this issue by not considering segment number limit when calcualting
bio's segment number.
Fixes: dcebd75592 ("block: use bio_for_each_bvec() to compute multi-page bvec count")
Cc: Christoph Hellwig <hch@lst.de>
Cc: Omar Sandoval <osandov@fb.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When the current bvec can be merged to the 1st segment, the bio's front
segment size has to be updated.
However, dcebd75592 doesn't consider that case, then bio's front
segment size may not be correct.
This patch fixes this issue.
Cc: Christoph Hellwig <hch@lst.de>
Cc: Omar Sandoval <osandov@fb.com>
Fixes: dcebd75592 ("block: use bio_for_each_bvec() to compute multi-page bvec count")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Replace hard coded function name register_blkdev with __func__, to
improve robustness and to conform to the Linux kernel coding
style. Issue found using checkpatch.
Signed-off-by: Keyur Patel <iamkeyur96@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If __device_add_disk-->bdi_register_owner-->bdi_register-->
bdi_register_va-->device_create_vargs fails, bdi->dev is still
NULL, __device_add_disk-->register_disk will visit bdi->dev->kobj.
This patch fixes that.
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
For an ITER_BVEC, we can just iterate the iov and add the pages
to the bio directly. For now, we grab a reference to those pages,
and release them normally on IO completion. This isn't really needed
for the normal case of O_DIRECT from/to a file, but some of the more
esoteric use cases (like splice(2)) will unconditionally put the
pipe buffer pages when the buffers are released. Until we can manage
that case properly, ITER_BVEC pages are treated like normal pages
in terms of reference counting.
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Introduce a fast path for single-page bvec IO, then we can avoid
to call bvec_split_segs() unnecessarily.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Introduce a fast path for single-page bvec IO, then blk_bvec_map_sg()
can be avoided.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Single-page bvec can often be seen in small BS workloads, so
introduce bvec_nth_page() for avoiding to call nth_page() unnecessarily,
which looks not cheap.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Block bounce needs to allocate new page for doing IO, and the
new page has to be updated to bvec table.
Commit 6dc4f100c switches __blk_queue_bounce() to use the new
bio_for_each_segment_all() interface. Unfortunately the new
bio_for_each_segment_all() can't be used to update bvec table.
This patch fixes this issue by retrieving bvec from the table
directly, then the new allocated page can be updated to the bio.
This way is safe because the cloned bio is single page bvec.
Fixes: 6dc4f100c ("block: allow bio_for_each_segment_all() to iterate over multi-page bvec")
Cc: Christoph Hellwig <hch@lst.de>
Cc: Omar Sandoval <osandov@fb.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
rq->bio can be NULL sometimes, such as flush request, so don't
read bio->bi_seg_front_size until this 'bio' is checked as valid.
Cc: Bart Van Assche <bvanassche@acm.org>
Reported-by: Bart Van Assche <bvanassche@acm.org>
Fixes: dcebd75592 ("block: use bio_for_each_bvec() to compute multi-page bvec count")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-----BEGIN PGP SIGNATURE-----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=8mjO
-----END PGP SIGNATURE-----
Merge tag 'for-linus-20190215' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
- Ensure we insert into the hctx dispatch list, if a request is marked
as DONTPREP (Jianchao)
- NVMe pull request, single missing unlock on error fix (Keith)
- MD pull request, single fix for a potentially data corrupting issue
(Nate)
- Floppy check_events regression fix (Yufen)
* tag 'for-linus-20190215' of git://git.kernel.dk/linux-block:
md/raid1: don't clear bitmap bits on interrupted recovery.
floppy: check_events callback should not return a negative number
nvme-pci: add missing unlock for reset error
blk-mq: insert rq with DONTPREP to hctx dispatch list when requeue
-----BEGIN PGP SIGNATURE-----
iQFRBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAlxgqNUeHHRvcnZhbGRz
QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGwsoH+OVXu0NQofwTvVru
8lgF3BSDG2mhf7mxbBBlBizGVy9jnjRNGCFMC+Jq8IwiFLwprja/G27kaDTkpuF1
PHC3yfjKvjTeUP5aNdHlmxv6j1sSJfZl0y46DQal4UeTG/Giq8TFTi+Tbz7Wb/WV
yCx4Lr8okAwTuNhnL8ojUCVIpd3c8QsyR9v6nEQ14Mj+MvEbokyTkMJV0bzOrM38
JOB+/X1XY4JPZ6o3MoXrBca3bxbAJzMneq+9CWw1U5eiIG3msg4a+Ua3++RQMDNr
8BP0yCZ6wo32S8uu0PI6HrZaBnLYi5g9Wh7Q7yc0mn1Uh1zWFykA6TtqK90agJeR
A6Ktjw==
=scY4
-----END PGP SIGNATURE-----
Merge tag 'v5.0-rc6' into for-5.1/block
Pull in 5.0-rc6 to avoid a dumb merge conflict with fs/iomap.c.
This is needed since io_uring is now based on the block branch,
to avoid a conflict between the multi-page bvecs and the bits
of io_uring that touch the core block parts.
* tag 'v5.0-rc6': (525 commits)
Linux 5.0-rc6
x86/mm: Make set_pmd_at() paravirt aware
MAINTAINERS: Update the ocores i2c bus driver maintainer, etc
blk-mq: remove duplicated definition of blk_mq_freeze_queue
Blk-iolatency: warn on negative inflight IO counter
blk-iolatency: fix IO hang due to negative inflight counter
MAINTAINERS: unify reference to xen-devel list
x86/mm/cpa: Fix set_mce_nospec()
futex: Handle early deadlock return correctly
futex: Fix barrier comment
net: dsa: b53: Fix for failure when irq is not defined in dt
blktrace: Show requests without sector
mips: cm: reprime error cause
mips: loongson64: remove unreachable(), fix loongson_poweroff().
sit: check if IPv6 enabled before calling ip6_err_gen_icmpv6_unreach()
geneve: should not call rt6_lookup() when ipv6 was disabled
KVM: nVMX: unconditionally cancel preemption timer in free_nested (CVE-2019-7221)
KVM: x86: work around leak of uninitialized stack contents (CVE-2019-7222)
kvm: fix kvm_ioctl_create_device() reference counting (CVE-2019-6974)
signal: Better detection of synchronous signals
...
QUEUE_FLAG_NO_SG_MERGE has been killed, so kill BLK_MQ_F_SG_MERGE too.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Since bdced438ac ("block: setup bi_phys_segments after splitting"),
physical segment number is mainly figured out in blk_queue_split() for
fast path, and the flag of BIO_SEG_VALID is set there too.
Now only blk_recount_segments() and blk_recalc_rq_segments() use this
flag.
Basically blk_recount_segments() is bypassed in fast path given BIO_SEG_VALID
is set in blk_queue_split().
For another user of blk_recalc_rq_segments():
- run in partial completion branch of blk_update_request, which is an unusual case
- run in blk_cloned_rq_check_limits(), still not a big problem if the flag is killed
since dm-rq is the only user.
Multi-page bvec is enabled now, not doing S/G merging is rather pointless with the
current setup of the I/O path, as it isn't going to save you a significant amount
of cycles.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This patch pulls the trigger for multi-page bvecs.
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This patch introduces one extra iterator variable to bio_for_each_segment_all(),
then we can allow bio_for_each_segment_all() to iterate over multi-page bvec.
Given it is just one mechannical & simple change on all bio_for_each_segment_all()
users, this patch does tree-wide change in one single patch, so that we can
avoid to use a temporary helper for this conversion.
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
It is more efficient to use bio_for_each_bvec() to map sg, meantime
we have to consider splitting multipage bvec as done in blk_bio_segment_split().
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
First it is more efficient to use bio_for_each_bvec() in both
blk_bio_segment_split() and __blk_recalc_rq_segments() to compute how
many multi-page bvecs there are in the bio.
Secondly once bio_for_each_bvec() is used, the bvec may need to be
splitted because its length can be very longer than max segment size,
so we have to split the big bvec into several segments.
Thirdly when splitting multi-page bvec into segments, the max segment
limit may be reached, so the bio split need to be considered under
this situation too.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
It is wrong to use bio->bi_vcnt to figure out how many segments
there are in the bio even though CLONED flag isn't set on this bio,
because this bio may be splitted or advanced.
So always use bio_segments() in blk_recount_segments(), and it shouldn't
cause any performance loss now because the physical segment number is figured
out in blk_queue_split() and BIO_SEG_VALID is set meantime since
bdced438ac ("block: setup bi_phys_segments after splitting").
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Fixes: 76d8137a31 ("blk-merge: recaculate segment if it isn't less than max segments")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When requeue, if RQF_DONTPREP, rq has contained some driver
specific data, so insert it to hctx dispatch list to avoid any
merge. Take scsi as example, here is the trace event log (no
io scheduler, because RQF_STARTED would prevent merging),
kworker/0:1H-339 [000] ...1 2037.209289: block_rq_insert: 8,0 R 4096 () 32768 + 8 [kworker/0:1H]
scsi_inert_test-1987 [000] .... 2037.220465: block_bio_queue: 8,0 R 32776 + 8 [scsi_inert_test]
scsi_inert_test-1987 [000] ...2 2037.220466: block_bio_backmerge: 8,0 R 32776 + 8 [scsi_inert_test]
kworker/0:1H-339 [000] .... 2047.220913: block_rq_issue: 8,0 R 8192 () 32768 + 16 [kworker/0:1H]
scsi_inert_test-1996 [000] ..s1 2047.221007: block_rq_complete: 8,0 R () 32768 + 8 [0]
scsi_inert_test-1996 [000] .Ns1 2047.221045: block_rq_requeue: 8,0 R () 32776 + 8 [0]
kworker/0:1H-339 [000] ...1 2047.221054: block_rq_insert: 8,0 R 4096 () 32776 + 8 [kworker/0:1H]
kworker/0:1H-339 [000] ...1 2047.221056: block_rq_issue: 8,0 R 4096 () 32776 + 8 [kworker/0:1H]
scsi_inert_test-1986 [000] ..s1 2047.221119: block_rq_complete: 8,0 R () 32776 + 8 [0]
(32768 + 8) was requeued by scsi_queue_insert and had RQF_DONTPREP.
Then it was merged with (32776 + 8) and issued. Due to RQF_DONTPREP,
the sdb only contained the part of (32768 + 8), then only that part
was completed. The lucky thing was that scsi_io_completion detected
it and requeued the remaining part. So we didn't get corrupted data.
However, the requeue of (32776 + 8) is not expected.
Suggested-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jianchao Wang <jianchao.w.wang@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There's no reason to freeze queue and remove scheduler
if there's no scheduler already.
Signed-off-by: Aleksei Zakharov <zakharov.a.g@yandex.ru>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There's no reason to set wbt min lat and freeze request queue
if current value is the same.
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Aleksei Zakharov <zakharov.a.g@yandex.ru>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The Notes section of the comment was removed, because now
blk_release_queue can only be executed from blk_cleanup_queue (being
called when the q->kobj reaches zero), and also blk_init_queue was removed
in a1ce35fa49.
Signed-off-by: Marcos Paulo de Souza <marcos.souza.org@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Since 4cf6324b17, a portion of function blk_cleanup_queue was moved to
a newly created function called blk_exit_queue, including the call of
blkcg_exit_queue. So, adjust the documenation according.
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Marcos Paulo de Souza <marcos.souza.org@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We have various helpers for setting/clearing this flag, and also
a helper to check if the queue supports queueable flushes or not.
But nobody uses them anymore, kill it with fire.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-----BEGIN PGP SIGNATURE-----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=tuL6
-----END PGP SIGNATURE-----
Merge tag 'for-linus-20190209' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
- NVMe pull request from Christoph, fixing namespace locking when
dealing with the effects log, and a rapid add/remove issue (Keith)
- blktrace tweak, ensuring requests with -1 sectors are shown (Jan)
- link power management quirk for a Smasung SSD (Hans)
- m68k nfblock dynamic major number fix (Chengguang)
- series fixing blk-iolatency inflight counter issue (Liu)
- ensure that we clear ->private when setting up the aio kiocb (Mike)
- __find_get_block_slow() rate limit print (Tetsuo)
* tag 'for-linus-20190209' of git://git.kernel.dk/linux-block:
blk-mq: remove duplicated definition of blk_mq_freeze_queue
Blk-iolatency: warn on negative inflight IO counter
blk-iolatency: fix IO hang due to negative inflight counter
blktrace: Show requests without sector
fs: ratelimit __find_get_block_slow() failure message.
m68k: set proper major_num when specifying module param major_num
libata: Add NOLPM quirk for SAMSUNG MZ7TE512HMHP-000L1 SSD
nvme-pci: fix rapid add remove sequence
nvme: lock NS list changes while handling command effects
aio: initialize kiocb private in case any filesystems expect it.
There's no reason to freeze queue and set nr_requests value
if current value is the same.
Signed-off-by: Aleksei Zakharov <zakharov.a.g@yandex.ru>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
As the prototype has been defined in "include/linux/blk-mq.h", the one
in "block/blk-mq.h" can be removed then.
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This is to catch any unexpected negative value of inflight IO counter.
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Our test reported the following stack, and vmcore showed that
->inflight counter is -1.
[ffffc9003fcc38d0] __schedule at ffffffff8173d95d
[ffffc9003fcc3958] schedule at ffffffff8173de26
[ffffc9003fcc3970] io_schedule at ffffffff810bb6b6
[ffffc9003fcc3988] blkcg_iolatency_throttle at ffffffff813911cb
[ffffc9003fcc3a20] rq_qos_throttle at ffffffff813847f3
[ffffc9003fcc3a48] blk_mq_make_request at ffffffff8137468a
[ffffc9003fcc3b08] generic_make_request at ffffffff81368b49
[ffffc9003fcc3b68] submit_bio at ffffffff81368d7d
[ffffc9003fcc3bb8] ext4_io_submit at ffffffffa031be00 [ext4]
[ffffc9003fcc3c00] ext4_writepages at ffffffffa03163de [ext4]
[ffffc9003fcc3d68] do_writepages at ffffffff811c49ae
[ffffc9003fcc3d78] __filemap_fdatawrite_range at ffffffff811b6188
[ffffc9003fcc3e30] filemap_write_and_wait_range at ffffffff811b6301
[ffffc9003fcc3e60] ext4_sync_file at ffffffffa030cee8 [ext4]
[ffffc9003fcc3ea8] vfs_fsync_range at ffffffff8128594b
[ffffc9003fcc3ee8] do_fsync at ffffffff81285abd
[ffffc9003fcc3f18] sys_fsync at ffffffff81285d50
[ffffc9003fcc3f28] do_syscall_64 at ffffffff81003c04
[ffffc9003fcc3f50] entry_SYSCALL_64_after_swapgs at ffffffff81742b8e
The ->inflight counter may be negative (-1) if
1) blk-iolatency was disabled when the IO was issued,
2) blk-iolatency was enabled before this IO reached its endio,
3) the ->inflight counter is decreased from 0 to -1 in endio()
In fact the hang can be easily reproduced by the below script,
H=/sys/fs/cgroup/unified/
P=/sys/fs/cgroup/unified/test
echo "+io" > $H/cgroup.subtree_control
mkdir -p $P
echo $$ > $P/cgroup.procs
xfs_io -f -d -c "pwrite 0 4k" /dev/sdg
echo "`cat /sys/block/sdg/dev` target=1000000" > $P/io.latency
xfs_io -f -d -c "pwrite 0 4k" /dev/sdg
This fixes the problem by freezing the queue so that while
enabling/disabling iolatency, there is no inflight rq running.
Note that quiesce_queue is not needed as this only updating iolatency
configuration about which dispatching request_queue doesn't care.
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Here are some driver core fixes for 5.0-rc6.
Well, not so much "driver core" as "debugfs". There's a lot of
outstanding debugfs cleanup patches coming in through different
subsystem trees, and in that process the debugfs core was found that it
really should return errors when something bad happens, to prevent
random files from showing up in the root of debugfs afterward. So
debugfs was fixed up to handle this properly, and then two fixes for
the relay and blk-mq code was needed as it was making invalid
assumptions about debugfs return values.
There's also a cacheinfo fix in here that resolves a tiny issue.
All of these have been in linux-next for over a week with no reported
problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-----BEGIN PGP SIGNATURE-----
iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCXF069g8cZ3JlZ0Brcm9h
aC5jb20ACgkQMUfUDdst+yk0+gCgy9PTVAJR5ZbYtWTJOTdBnd7pfqMAoMuGxc+6
LLEbfSykLRxEf5SeOJun
=KP8e
-----END PGP SIGNATURE-----
Merge tag 'driver-core-5.0-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core fixes from Greg KH:
"Here are some driver core fixes for 5.0-rc6.
Well, not so much "driver core" as "debugfs". There's a lot of
outstanding debugfs cleanup patches coming in through different
subsystem trees, and in that process the debugfs core was found that
it really should return errors when something bad happens, to prevent
random files from showing up in the root of debugfs afterward. So
debugfs was fixed up to handle this properly, and then two fixes for
the relay and blk-mq code was needed as it was making invalid
assumptions about debugfs return values.
There's also a cacheinfo fix in here that resolves a tiny issue.
All of these have been in linux-next for over a week with no reported
problems"
* tag 'driver-core-5.0-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
blk-mq: protect debugfs_create_files() from failures
relay: check return of create_buf_file() properly
debugfs: debugfs_lookup() should return NULL if not found
debugfs: return error values, not NULL
debugfs: fix debugfs_rename parameter checking
cacheinfo: Keep the old value if of_property_read_u32 fails
Unused now, and another field in struct request bites the dust.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
No users left.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
We can just stash away the second request in struct bsg_job instead of
using the block layer req->next_rq field, allowing for the eventual removal
of the latter.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Move all actual functionality into helpers, just leaving the dispatch in
this function.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Tested-by: Benjamin Block <bblock@linux.ibm.com>
Tested-by: Avri Altman <avri.altman@wdc.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Currently, we check whether the hctx type is supported every time
in hot path. Actually, this is not necessary, we could save the
default hctx into ctx->hctxs if the type is not supported when
map swqueues and use it directly with ctx->hctxs[type].
We also needn't check whether the poll is enabled or not, because
the caller would clear the REQ_HIPRI in that case.
Signed-off-by: Jianchao Wang <jianchao.w.wang@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently, the queue mapping result is saved in a two-dimensional
array. In the hot path, to get a hctx, we need do following:
q->queue_hw_ctx[q->tag_set->map[type].mq_map[cpu]]
This isn't very efficient. We could save the queue mapping result into
ctx directly with different hctx type, like,
ctx->hctxs[type]
Signed-off-by: Jianchao Wang <jianchao.w.wang@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When a new I/O request arrives for a bfq_queue, say Q, bfq checks
whether that request is close to
(a) the head request of some other queue waiting to be served, or
(b) the last request dispatched for the in-service queue (in case Q
itself is not the in-service queue)
If a queue, say Q2, is found for which the above condition holds, then
bfq merges Q and Q2, to hopefully get a more sequential I/O in the
resulting merged queue, and thus a possibly higher throughput.
Case (b) is checked by comparing the new request for Q with the last
request dispatched, assuming that the latter necessarily belonged to the
in-service queue. Unfortunately, this assumption is no longer always
correct, since commit d0edc2473b ("block, bfq: inject other-queue I/O
into seeky idle queues on NCQ flash").
When the assumption does not hold, queues that must not be merged may be
merged, causing unexpected loss of control on per-queue service
guarantees.
This commit solves this problem by adding an extra field, which stores
the actual last request dispatched for the in-service queue, and by
using this new field to correctly check case (b).
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Writes tend to starve reads. bfq counters this problem by overcharging
writes with an inflated service w.r.t. the actual service (number of
sector written) they receive.
Yet his overcharging is useless, and actually causes unfairness in the
opposite direction, when bfq happens to be enforcing strong I/O control.
bfq does this enforcing when the scenario is asymmetric, i.e., when some
bfq_queue or group of bfq_queues is to be granted a different bandwidth
than some other bfq_queue or group of bfq_queues. So, in such a
scenario, this commit disables write overcharging.
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The original commit is commit 1a1238a7dd ("cfq-iosched: improve hw_tag
detection") and has the following commit message:
If active queue hasn't enough requests and idle window opens, cfq will
not dispatch sufficient requests to hardware. In such situation, current
code will zero hw_tag. But this is because cfq doesn't dispatch enough
requests instead of hardware queue doesn't work. Don't zero hw_tag in
such case.
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
bfq simple heuristic from cfq for detecting whether the drive performs
command queueing: check whether the average number of in-flight requests
is above a given threshold. Unfortunately this heuristic does fail to
detect queueing (on drives with queueing) if processes doing I/O are few
and issue I/O with a low depth.
To reduce false negatives, this commit lowers the threshold.
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
bfq maintains an ordered list, through a red-black tree, of unique
weights of active bfq_queues. This list is used to detect whether there
are active queues with differentiated weights. The weight of a queue is
removed from the list when both the following two conditions become
true:
(1) the bfq_queue is flagged as inactive
(2) the has no in-flight request any longer;
Unfortunately, in the rare cases where condition (2) becomes true before
condition (1), the removal fails, because the function to remove the
weight of the queue (bfq_weights_tree_remove) is rightly invoked in the
path that deactivates the bfq_queue, but mistakenly invoked *before* the
function that actually performs the deactivation (bfq_deactivate_bfqq).
This commits moves the invocation of bfq_weights_tree_remove for
condition (1) to after bfq_deactivate_bfqq. As a consequence of this
move, it is necessary to add a further reference to the queue when the
weight of a queue is added, because the queue might otherwise be freed
before bfq_weights_tree_remove is invoked. This commit adds this
reference and makes all related modifications.
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In bfq_update_peak_rate, to check whether an I/O request rq is
sequential, only the seek distance of rq w.r.t. the last request
dispatched is controlled. This is not sufficient for non-rotational
storage, where the size of rq is at least as relevant. This commit adds
the missing control.
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
bfq detects the creation of multiple bfq_queues shortly after each
other, namely a burst of queue creations in the terminology used in the
code. If the burst is large, then no queue in the burst is granted
- either I/O-dispatch plugging when the queue remains temporarily idle
while in service;
- or weight raising, because it causes even longer plugging.
In fact, such a plugging tends to lower throughput, while these bursts
are typically due to applications or services that spawn multiple
processes, to reach a common goal as soon as possible. Examples are a
"git grep" or the booting of a system.
Unfortunately, disabling plugging may cause a loss of service guarantees
in asymmetric scenarios, i.e., if queue weights are differentiated or if
more than one group is active.
This commit addresses this issue by no longer disabling I/O-dispatch
plugging for queues in large bursts.
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Linus Torvalds
Nikolay Borisov
Ming Lei
Keyur Patel
zhengbin
Dongli Zhang
Jens Axboe
Jianchao Wang
Aleksei Zakharov
Marcos Paulo de Souza
Liu Bo
Christoph Hellwig
Paolo Valente