Some ublk selftests have strange behavior when fio is not installed.
While most tests behave correctly (run if they don't need fio, or skip
if they need fio), the following tests have different behavior:
- test_null_01, test_null_02, test_generic_01, test_generic_02, and
test_generic_12 try to run fio without checking if it exists first,
and fail on any failure of the fio command (including "fio command
not found"). So these tests fail when they should skip.
- test_stress_05 runs fio without checking if it exists first, but
doesn't fail on fio command failure. This test passes, but that pass
is misleading as the test doesn't do anything useful without fio
installed. So this test passes when it should skip.
Fix these issues by adding _have_program fio checks to the top of all of
these tests.
Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add a test that verifies that the currently running kernel does not
report support for any features that are unrecognized by kublk. This
should catch cases where features are added without updating kublk's
feat_map accordingly, which has happened multiple times in the past (see
[1], [2]).
Note that this new test may fail if the test suite is older than the
kernel, and the newer kernel contains a newly introduced feature. I
believe this is not a use case we currently care about - we only care
about newer test suites passing on older kernels.
[1] https://lore.kernel.org/linux-block/20250606214011.2576398-1-csander@purestorage.com/t/#u
[2] https://lore.kernel.org/linux-block/2a370ab1-d85b-409d-b762-f9f3f6bdf705@nvidia.com/t/#m1c520a058448d594fd877f07804e69b28908533f
Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When UBLK_F_BUF_REG_OFF_DAEMON was added, we missed updating kublk's
feat_map, which results in the feature being reported as "unknown." Add
UBLK_F_BUF_REG_OFF_DAEMON to feat_map to fix this.
Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Simplify the definition of feat_map by introducing a helper macro
FEAT_NAME to avoid having to type the feature name twice. As a side
effect, this changes the names in the feature list to be the full macro
name instead of the abbreviated names that were used before, but this is
a good change for clarity.
Using the full feature macro names ruins the alignment of the output, so
change the output format to put each feature's hex value before its
name, as this is easier to align nicely. The output now looks as
follows:
root# ./kublk features
ublk_drv features: 0x7fff
0x1 : UBLK_F_SUPPORT_ZERO_COPY
0x2 : UBLK_F_URING_CMD_COMP_IN_TASK
0x4 : UBLK_F_NEED_GET_DATA
0x8 : UBLK_F_USER_RECOVERY
0x10 : UBLK_F_USER_RECOVERY_REISSUE
0x20 : UBLK_F_UNPRIVILEGED_DEV
0x40 : UBLK_F_CMD_IOCTL_ENCODE
0x80 : UBLK_F_USER_COPY
0x100 : UBLK_F_ZONED
0x200 : UBLK_F_USER_RECOVERY_FAIL_IO
0x400 : UBLK_F_UPDATE_SIZE
0x800 : UBLK_F_AUTO_BUF_REG
0x1000 : UBLK_F_QUIESCE
0x2000 : UBLK_F_PER_IO_DAEMON
0x4000 : unknown
Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Use ARRAY_SIZE() macro while calculating size of an array to improve
code readability and reduce potential sizing errors.
Implement this suggestion given by spatch tool by running
coccinelle script - scripts/coccinelle/misc/array_size.cocci
Follow ARRAY_SIZE() macro usage pattern in ublk.c introduced by,
commit ec12009318 ("selftests: ublk: fix ublk_find_tgt()")
wherever appropriate to maintain consistency.
Signed-off-by: Akhilesh Patil <akhilesh@ee.iitb.ac.in>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/aKGihYui6/Pcijbk@bhairav-test.ee.iitb.ac.in
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pass 'ublk_thread *' to more common helpers, then we can avoid to store
this reference into 'struct ublk_io'.
Prepare for supporting to handle IO via different task context.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250713143415.2857561-14-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
'struct thread' is task local structure, and the related code will become
more readable if we pass it via parameter.
Meantime pass 'ublk_thread *' to ublk_io_alloc_sqes(), and this way is
natural since we use per-thread io_uring for handling IO.
More importantly it helps much for removing the current ubq_daemon or
per-io-task limit.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250713143415.2857561-13-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The `tag` parameter can be figured out from cqe->user_data, and that is
also the only way to get the info, so remove `tag` parameter, and
let target code retrieve it from cqe->user_data.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250713143415.2857561-12-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Don't use same backing file for more than one ublk devices, and avoid
concurrent write on same file from more ublk disks.
Fixes: 8ccebc19ee ("selftests: ublk: support UBLK_F_AUTO_BUF_REG")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250623011934.741788-3-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Some failure modes are handled poorly by kublk. For example, if ublk_drv
is built as a module but not currently loaded into the kernel, ./kublk
add ... just hangs forever. This happens because in this case (and a few
others), the worker process does not notify its parent (via a write to
the shared eventfd) that it has tried and failed to initialize, so the
parent hangs forever. Fix this by ensuring that we always notify the
parent process of any initialization failure, and have the parent print
a (not very descriptive) log line when this happens.
Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250603-ublk_init_fail-v1-1-87c91486230e@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We have stress_03, stress_04 and stress_05 for checking new feature vs.
stress IO & device removal & ublk server crash & recovery, so let the
three existing stress tests cover PER_IO_DAEMON.
Then stress_06 can be removed, since the same test function is included in
stress_03.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250602132113.1398645-1-ming.lei@redhat.com
Reviewed-by: Uday Shankar <ushankar@purestorage.com>
[axboe: remove test_stress_06.sh from Makefile too]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add a new test_stress_06 for the per io daemons feature. This is just a
copy of test_stress_01 with the per_io_tasks flag added, with varying
amounts of nthreads. This test is able to reproduce a panic which was
caught manually during development [1]; in the current version of this
patch set, it passes.
Note that this commit also makes all stress tests using the
run_io_and_remove helper more stressful by additionally exercising the
batch submit (queue_rqs) path.
[1] https://lore.kernel.org/linux-block/aDgwGoGCEpwd1mFY@fedora/
Suggested-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Link: https://lore.kernel.org/r/20250529-ublk_task_per_io-v8-8-e9d3b119336a@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add a new test test_generic_12 which:
- sets up a ublk server with per_io_tasks and a different number of ublk
server threads and ublk_queues. This is possible now that these
objects are decoupled
- runs some I/O load from a single CPU
- verifies that all the ublk server threads handle some I/O
Before this changeset, this test fails, since I/O issued from one CPU is
always handled by the one ublk server thread. After this changeset, the
test passes.
In the future, the last check above may be strengthened to "verify that
all ublk server threads handle the same amount of I/O." However, this
requires some adjustments/bugfixes to tag allocation, so this work is
postponed to a followup.
Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250529-ublk_task_per_io-v8-7-e9d3b119336a@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add support in kublk for decoupled ublk_queues and ublk server threads.
kublk now has two modes of operation:
- (preexisting mode) threads and queues are paired 1:1, and each thread
services all the I/Os of one queue
- (new mode) thread and queue counts are independently configurable.
threads service I/Os in a way that balances load across threads even
if load is not balanced over queues.
The default is the preexisting mode. The new mode is activated by
passing the --per_io_tasks flag.
Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250529-ublk_task_per_io-v8-6-e9d3b119336a@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Towards the goal of decoupling ublk_queues from ublk server threads,
move resources/data that should be per-thread rather than per-queue out
of ublk_queue and into a new struct ublk_thread.
Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250529-ublk_task_per_io-v8-5-e9d3b119336a@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently, each ublk server I/O handler thread initializes its own
queue. However, as we move towards decoupled ublk_queues and ublk server
threads, this model does not make sense anymore, as there will no longer
be a concept of a thread having "its own" queue. So lift queue
initialization out of the per-thread ublk_io_handler_fn and into a loop
in ublk_start_daemon (which runs once for each device).
There is a part of ublk_queue_init (ring initialization) which does
actually need to happen on the thread that will use the ring; that is
separated into a separate ublk_thread_init which is still called by each
I/O handler thread.
Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250529-ublk_task_per_io-v8-4-e9d3b119336a@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We currently have a helper ublk_queue_alloc_sqes which the ublk targets
use to allocate SQEs for their own operations. However, as we move
towards decoupled ublk_queues and ublk server threads, this helper does
not make sense anymore. SQEs are allocated from rings, and we will have
one ring per thread to avoid locking. Change the SQE allocation helper
to ublk_io_alloc_sqes. Currently this still allocates SQEs from the io's
queue's ring, but when we fully decouple threads and queues, it will
allocate from the io's thread's ring instead.
Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250529-ublk_task_per_io-v8-3-e9d3b119336a@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently, when we process CQEs, we know which ublk_queue we are working
on because we know which ring we are working on, and ublk_queues and
rings are in 1:1 correspondence. However, as we decouple ublk_queues
from ublk server threads, ublk_queues and rings will no longer be in 1:1
correspondence - each ublk server thread will have a ring, and each
thread may issue commands against more than one ublk_queue. So in order
to know which ublk_queue a CQE refers to, plumb that information in the
associated SQE's user_data.
Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250529-ublk_task_per_io-v8-2-e9d3b119336a@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add test generic_10 for covering new control command of UBLK_U_CMD_UPDATE_SIZE.
Add 'update_size -s|--size size_in_bytes' sub-command on ublk utility for
supporting this feature, then verify the feature via generic_10.
Cc: Omri Mann <omri@nvidia.com>
Cc: Jared Holzman <jholzman@nvidia.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250522163523.406289-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add test for covering UBLK_AUTO_BUF_REG_FALLBACK:
- pass '--auto_zc_fallback' to null target, which requires both F_AUTO_BUF_REG
and F_SUPPORT_ZERO_COPY for handling UBLK_AUTO_BUF_REG_FALLBACK
- add ->buf_index() method for returning invalid buffer index to trigger
UBLK_AUTO_BUF_REG_FALLBACK
- add generic_09 for running the test
- add --auto_zc_fallback test in stress_03/stress_04/stress_05
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250520045455.515691-7-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Enable UBLK_F_AUTO_BUF_REG support for ublk utility by argument `--auto_zc`,
meantime support this feature in null, loop and stripe target code.
Add function test generic_08 for covering basic UBLK_F_AUTO_BUF_REG feature.
Also cover UBLK_F_AUTO_BUF_REG in stress_03, stress_04 and stress_05 test too.
'fio/t/io_uring -p0 /dev/ublkb0' shows that F_AUTO_BUF_REG can improve
IOPS by 50% compared with F_SUPPORT_ZERO_COPY in my test VM.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250520045455.515691-6-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
__run_io_and_remove() is used in several stress tests for running heavy
IO vs. removing device meantime.
However, sequential `readwrite` is taken in the fio script, which isn't
correct, we should take random IO for saturating ublk device.
Also turns out '--num_jobs=4' isn't stressful enough, so change it to
'--num_jobs=$(nproc)'.
Finally we don't cover single queue test in `test_stress_02.sh`, so add
single queue test which can trigger request tag recycling easier.
With above change the issue in #1 can be reproduced reliably in stress_02.sh.
Link:https://lore.kernel.org/linux-block/mruqwpf4tqenkbtgezv5oxwq7ngyq24jzeyqy4ixzvivatbbxv@4oh2wzz4e6qn/#1
Cc: Jared Holzman <jholzman@nvidia.com>
Cc: Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250519031620.245749-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Building kublk currently fails (with a "could not find linux/ublk_cmd.h"
error message) if kernel headers are not installed in a system-global
location (i.e. somewhere in the compiler's default include search path).
This failure is unnecessary, as make kselftest installs kernel headers
in the build tree - kublk's build just isn't looking for them properly.
There is an include path in kublk's CFLAGS which is probably intended to
find the kernel headers installed in the build tree; fix it so that it
can actually find them.
This introduces some macro redefinition issues between glibc-provided
headers and kernel headers; fix those by eliminating one include in
kublk.
Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250429-ublk_selftests-v2-3-e970b6d9e4f4@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Convention dictates that tests should not log anything on success. Make
test_generic_06 follow this convention.
Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250429-ublk_selftests-v2-2-e970b6d9e4f4@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Compiler warnings can catch bugs at compile time; thus, heeding them is
usually a good idea. Turn warnings into errors by default for the kublk
build so that anyone making changes is forced to heed them. Compiler
warnings can also sometimes produce annoying false positives, so provide
a flag WERROR that the developer can use as follows to have the build
and selftests run go through even if there are warnings:
make WERROR=0 TARGETS=ublk kselftest
Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250429-ublk_selftests-v2-1-e970b6d9e4f4@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Commit 57e13a2e8c ("selftests: ublk: support user recovery") starts to
support UBLK_F_NEED_GET_DATA for covering recovery feature, however the
ublk utility implementation isn't done correctly.
Fix it by supporting UBLK_F_NEED_GET_DATA correctly.
Also add test generic_07 for covering UBLK_F_NEED_GET_DATA.
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Fixes: 57e13a2e8c ("selftests: ublk: support user recovery")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250429022941.1718671-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Some distributions, such as centos stream 9, still have a version of
coreutils which does not yet support the %Hr and %Lr formats for stat(1)
[1, 2]. Running ublk selftests on these distributions results in the
following error in tests that use the _get_disk_dev_t helper:
line 23: ?r: syntax error: operand expected (error token is "?r")
To better accommodate older distributions, rewrite _get_disk_dev_t to
use the much older %t and %T formats for stat instead.
[1] https://github.com/coreutils/coreutils/blob/v9.0/NEWS#L114
[2] https://pkgs.org/download/coreutils
Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250423-ublk_selftests-v1-2-7d060e260e76@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
'delay_us' shouldn't be added to 'struct dev_ctx' since now it is
handled by per-target command line & 'struct fault_inject_ctx'.
So remove it.
Fixes: 81586652bb ("selftests: ublk: add generic_06 for covering fault inject")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Uday Shankar <ushankar@purestorage.com>
Link: https://lore.kernel.org/r/20250421235947.715272-3-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When adding recovery test:
- 'break' is missed for handling '-g' argument
- test name of test_generic_05.sh is wrong
So fix the two.
Fixes: 57e13a2e8c ("selftests: ublk: support user recovery")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Uday Shankar <ushankar@purestorage.com>
Link: https://lore.kernel.org/r/20250421235947.715272-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add one simple fault inject target, and verify if an application using ublk
device sees an I/O error quickly after the ublk server dies.
Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250416035444.99569-9-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
test may exit early because of missing program or not having required
feature before calling _prep_test(), then $UBLK_TMP isn't cleaned.
Fix it by moving creating $UBLK_TMP into _prep_test(), any resources
created since _prep_test() will be cleaned by _cleanup_test().
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250412023035.2649275-14-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Support target specific command line for making related command line code
handling more readable & clean.
Also helps for adding new features.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250412023035.2649275-11-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In NUMA machine, ublk IO performance is very sensitive with queue
pthread's affinity setting.
Retrieve queue's affinity and select the 1st cpu as queue thread's sched
affinity, and it is observed that single cpu task affinity can get
stable & good performance if client application is put on proper cpu.
Dump this info when adding one ublk device. Use shmem to communicate
queue's tid between parent and daemon.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250412023035.2649275-9-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Detach ublk daemon from the starting process completely by double-fork and
clearing its process group, so that `_add_ublk_dev` can return from sub-shell.
Then it is more friendly for writing shell test script for adding/recovering
ublk device.
Prepare for running ublk test in parallel.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250412023035.2649275-5-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add io_uring UAPI header so that ublk can work with latest uapi
definition.
Fix the following build failure:
stripe.c: In function ‘stripe_to_uring_op’:
stripe.c:120:29: error: ‘IORING_OP_READV_FIXED’ undeclared (first use in this function); did you mean ‘IORING_OP_READ_FIXED’?
120 | return zc ? IORING_OP_READV_FIXED : IORING_OP_READV;
| ^~~~~~~~~~~~~~~~~~~~~
| IORING_OP_READ_FIXED
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Fixes: 57ed58c132 ("selftests: ublk: enable zero copy for stripe target")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250412023035.2649275-3-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Bounds check for iterator variable `i` is missed, so add it and fix
ublk_find_tgt().
Cc: Johannes Thumshirn <Johannes.Thumshirn@wdc.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250412023035.2649275-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Commit 57ed58c132 ("selftests: ublk: enable zero copy for stripe target")
added test entry of test_stripe_04, but forgot to add the test script.
So fix the test by adding the script file.
Reported-by: Uday Shankar <ushankar@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Uday Shankar <ushankar@purestorage.com>
Link: https://lore.kernel.org/r/20250404001849.1443064-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Uday Shankar
Akhilesh Patil
Ming Lei