We source root cgroup stats from the system-wide stats, see blkcg_print_stat
and blkcg_rstat_flush, so don't update io state for root cgroup.
Fixes blkg leak issue introduced in commit 3b8cc62987 ("blk-cgroup: Optimize blkcg_rstat_flush()")
which starts to grab blkg's reference when adding iostat_cpu into percpu
blkcg list, but this state won't be consumed by blkcg_rstat_flush() where
the blkg reference is dropped.
Tested-by: Bart van Assche <bvanassche@acm.org>
Reported-by: Bart van Assche <bvanassche@acm.org>
Fixes: 3b8cc62987 ("blk-cgroup: Optimize blkcg_rstat_flush()")
Cc: Tejun Heo <tj@kernel.org>
Cc: Waiman Long <longman@redhat.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20230202021804.278582-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Commit 2b3f056f72 moved a blk_put_queue() call from
blk_mq_destroy_queue() into its callers. Reflect this change in the
documentation block above blk_mq_destroy_queue().
Cc: Christoph Hellwig <hch@lst.de>
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: Chaitanya Kulkarni <kch@nvidia.com>
Cc: Keith Busch <kbusch@kernel.org>
Fixes: 2b3f056f72 ("blk-mq: move the call to blk_put_queue out of blk_mq_destroy_queue")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230130211233.831613-1-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Assuming that both Kconfig options, BLK_CGROUP and IOSCHED_BFQ are set, we
most likely want cgroup support for BFQ too (BFQ_GROUP_IOSCHED), so let's
make it default y.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20230130121240.159456-1-ulf.hansson@linaro.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
bfqd->bfq_wr_max_time is set to 0 in bfq_init_queue and is never changed.
It is only used in bfq_wr_duration when bfq_wr_max_time > 0 which never
meets, so bfqd->bfq_wr_max_time is not used actually. Just remove it.
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230116095153.3810101-9-shikemeng@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We jump to tag only for returning current rq. Return directly to
remove this tag.
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Link: https://lore.kernel.org/r/20230116095153.3810101-8-shikemeng@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We have already avoided a circular list in bfq_setup_merge (see comments
in bfq_setup_merge() for details), so bfq_queue will not appear in it's
new_bfqq list. Just remove this check.
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230116095153.3810101-7-shikemeng@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Inject limit is updated or reset when time_is_before_eq_jiffies(
decrease_time_jif + several msecs) or think-time state changes.
decrease_time_jif is initialized to 0 and will be set to current jiffies
when inject limit is updated or reset. If the jiffies is slightly greater
than LONG_MAX, time_is_after_eq_jiffies(0) will keep for a long time, so as
time_is_after_eq_jiffies(decrease_time_jif + several msecs). If the
think-time state never chages, then the injection will not work as expected
for long time.
To be more specific:
Function bfq_update_inject_limit maybe triggered when jiffies pasts
decrease_time_jif + msecs_to_jiffies(10) in bfq_add_request by setting
bfqd->wait_dispatch to true.
Function bfq_reset_inject_limit are called in two conditions:
1. jiffies pasts bfqq->decrease_time_jif + msecs_to_jiffies(1000) in
function bfq_add_request.
2. jiffies pasts bfqq->decrease_time_jif + msecs_to_jiffies(100) or
bfq think-time state change from short to long.
Fix this by initializing bfqq->decrease_time_jif to current jiffies
to trigger service injection soon when service injection conditions
are met.
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230116095153.3810101-4-shikemeng@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Function bfq_choose_bfqq_for_injection may temporarily raise inject limit
to one request if current inject_limit is 0 before search of the source
queue for injection. However the search below will reset inject limit to
bfqd->in_service_queue which is zero for raised inject limit. Then the
temporarily raised inject limit never works as expected.
Assigment limit to bfqd->in_service_queue in search is needed as limit
maybe overwriten to min_t(unsigned int, 1, limit) for condition that
a large in-flight request is on non-rotational devices in found queue.
So we need to reset limit to bfqd->in_service_queue for normal case.
Actually, we have already make sure bfqd->rq_in_driver is < limit before
search, then
-Limit is >= 1 as bfqd->rq_in_driver is >= 0. Then min_t(unsigned int,
1, limit) is always 1. So we can simply check bfqd->rq_in_driver with
1 instead of result of min_t(unsigned int, 1, limit) for larget request in
non-rotational device case to avoid overwritting limit and the bug is gone.
-For normal case, we have already check bfqd->rq_in_driver is < limit,
so we can return found bfqq unconditionally to remove unncessary check.
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230116095153.3810101-2-shikemeng@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
After commit 64dc8c732f ("block, bfq: fix possible uaf for 'bfqq->bic'"),
bic->bfqq will be accessed in bic_set_bfqq(), however, in some context
bic->bfqq will be freed, and bic_set_bfqq() is called with the freed
bic->bfqq.
Fix the problem by always freeing bfqq after bic_set_bfqq().
Fixes: 64dc8c732f ("block, bfq: fix possible uaf for 'bfqq->bic'")
Reported-and-tested-by: Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230130014136.591038-1-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently parent pd can be freed before child pd:
t1: remove cgroup C1
blkcg_destroy_blkgs
blkg_destroy
list_del_init(&blkg->q_node)
// remove blkg from queue list
percpu_ref_kill(&blkg->refcnt)
blkg_release
call_rcu
t2: from t1
__blkg_release
blkg_free
schedule_work
t4: deactivate policy
blkcg_deactivate_policy
pd_free_fn
// parent of C1 is freed first
t3: from t2
blkg_free_workfn
pd_free_fn
If policy(for example, ioc_timer_fn() from iocost) access parent pd from
child pd after pd_offline_fn(), then UAF can be triggered.
Fix the problem by delaying 'list_del_init(&blkg->q_node)' from
blkg_destroy() to blkg_free_workfn(), and using a new disk level mutex to
synchronize blkg_free_workfn() and blkcg_deactivate_policy().
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230119110350.2287325-4-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
A new field 'online' is added to blkg_policy_data to fix following
2 problem:
1) In blkcg_activate_policy(), if pd_alloc_fn() with 'GFP_NOWAIT'
failed, 'queue_lock' will be dropped and pd_alloc_fn() will try again
without 'GFP_NOWAIT'. In the meantime, remove cgroup can race with
it, and pd_offline_fn() will be called without pd_init_fn() and
pd_online_fn(). This way null-ptr-deference can be triggered.
2) In order to synchronize pd_free_fn() from blkg_free_workfn() and
blkcg_deactivate_policy(), 'list_del_init(&blkg->q_node)' will be
delayed to blkg_free_workfn(), hence pd_offline_fn() can be called
first in blkg_destroy(), and then blkcg_deactivate_policy() will
call it again, we must prevent it.
The new field 'online' will be set after pd_online_fn() and will be
cleared after pd_offline_fn(), in the meantime pd_offline_fn() will only
be called if 'online' is set.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230119110350.2287325-3-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Some cgroup policies will access parent pd through child pd even
after pd_offline_fn() is done. If pd_free_fn() for parent is called
before child, then UAF can be triggered. Hence it's better to guarantee
the order of pd_free_fn().
Currently refcount of parent blkg is dropped in __blkg_release(), which
is before pd_free_fn() is called in blkg_free_work_fn() while
blkg_free_work_fn() is called asynchronously.
This patch make sure pd_free_fn() called from removing cgroup is ordered
by delaying dropping parent refcount after calling pd_free_fn() for
child.
BTW, pd_free_fn() will also be called from blkcg_deactivate_policy()
from deleting device, and following patches will guarantee the order.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230119110350.2287325-2-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We found that the blk_mq_hw_sysfs_store interface has no place to use.
The object default_hw_ctx_attrs using blk_mq_hw_sysfs_ops only uses
the show method and does not use the store method.
Since this patch:
4a46f05ebf ("blk-mq: move hctx and ctx counters from sysfs to debugfs")
moved the store method to debugfs, the store method is not used anymore.
So let me do some tiny work to clean up unused code.
Signed-off-by: Zhong Jinghua <zhongjinghua@huawei.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20230128030419.2780298-1-zhongjinghua@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We ran into an issue where a production workload would randomly grind to
a halt and not continue until the pending IO had timed out. This turned
out to be a complicated interaction between queue freezing and polled
IO:
1) You have an application that does polled IO. At any point in time,
there may be polled IO pending.
2) You have a monitoring application that issues a passthrough command,
which is marked with side effects such that it needs to freeze the
queue.
3) Passthrough command is started, which calls blk_freeze_queue_start()
on the device. At this point the queue is marked frozen, and any
attempt to enter the queue will fail (for non-blocking) or block.
4) Now the driver calls blk_mq_freeze_queue_wait(), which will return
when the queue is quiesced and pending IO has completed.
5) The pending IO is polled IO, but any attempt to poll IO through the
normal iocb_bio_iopoll() -> bio_poll() will fail when it gets to
bio_queue_enter() as the queue is frozen. Rather than poll and
complete IO, the polling threads will sit in a tight loop attempting
to poll, but failing to enter the queue to do so.
The end result is that progress for either application will be stalled
until all pending polled IO has timed out. This causes obvious huge
latency issues for the application doing polled IO, but also long delays
for passthrough command.
Fix this by treating queue enter for polled IO just like we do for
timeouts. This allows quick quiesce of the queue as we still poll and
complete this IO, while still disallowing queueing up new IO.
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
vrate_min is calculated by DIV64_U64_ROUND_UP, but vrate_max is calculated
by div64_u64. Vrate_min may be 1 greater than vrate_max if the input
values min and max of cost.qos are equal.
Signed-off-by: Li Nan <linan122@huawei.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230117070806.3857142-6-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
echo max of u64 to cost.model can cause divide by 0 error.
# echo 8:0 rbps=18446744073709551615 > /sys/fs/cgroup/io.cost.model
divide error: 0000 [#1] PREEMPT SMP
RIP: 0010:calc_lcoefs+0x4c/0xc0
Call Trace:
<TASK>
ioc_refresh_params+0x2b3/0x4f0
ioc_cost_model_write+0x3cb/0x4c0
? _copy_from_iter+0x6d/0x6c0
? kernfs_fop_write_iter+0xfc/0x270
cgroup_file_write+0xa0/0x200
kernfs_fop_write_iter+0x17d/0x270
vfs_write+0x414/0x620
ksys_write+0x73/0x160
__x64_sys_write+0x1e/0x30
do_syscall_64+0x35/0x80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
calc_lcoefs() uses the input value of cost.model in DIV_ROUND_UP_ULL,
overflow would happen if bps plus IOC_PAGE_SIZE is greater than
ULLONG_MAX, it can cause divide by 0 error.
Fix the problem by setting basecost
Signed-off-by: Li Nan <linan122@huawei.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230117070806.3857142-5-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
iocost is based on rq_qos, which can only work for request based device,
thus it doesn't make sense to configure iocost for bio based device.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230117070806.3857142-3-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The behavior of 'enum' types has changed in gcc-13, so now the
UNBUSY_THR_PCT constant is interpreted as a 64-bit number because
it is defined as part of the same enum definition as some other
constants that do not fit within a 32-bit integer. This in turn
leads to some inefficient code on 32-bit architectures as well
as a link error:
arm-linux-gnueabi/bin/arm-linux-gnueabi-ld: block/blk-iocost.o: in function `ioc_timer_fn':
blk-iocost.c:(.text+0x68e8): undefined reference to `__aeabi_uldivmod'
arm-linux-gnueabi-ld: blk-iocost.c:(.text+0x6908): undefined reference to `__aeabi_uldivmod'
Split the enum definition to keep the 64-bit timing constants in
a separate enum type from those constants that can clearly fit
within a smaller type.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230118080706.3303186-1-arnd@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Instead of open coding to check for zone start, add a helper to improve
readability and store the logic in one place.
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Pankaj Raghav <p.raghav@samsung.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20230110143635.77300-3-p.raghav@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This patch modifies the present check, so that bio-cache is not limited
to iopoll.
Signed-off-by: Anuj Gupta <anuj20.g@samsung.com>
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Link: https://lore.kernel.org/r/20230117120638.72254-3-anuj20.g@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If we're doing a large IO request which needs to be split into multiple
bios for issue, then we can run into the same situation as the below
marked commit fixes - parts will complete just fine, one or more parts
will fail to allocate a request. This will result in a partially
completed read or write request, where the caller gets EAGAIN even though
parts of the IO completed just fine.
Do the same for large bios as we do for splits - fail a NOWAIT request
with EAGAIN. This isn't technically fixing an issue in the below marked
patch, but for stable purposes, we should have either none of them or
both.
This depends on: 613b14884b ("block: handle bio_split_to_limits() NULL return")
Cc: stable@vger.kernel.org # 5.15+
Fixes: 9cea62b2cb ("block: don't allow splitting of a REQ_NOWAIT bio")
Link: https://github.com/axboe/liburing/issues/766
Reported-and-tested-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We have BIO_FLAG_LAST in the enum for bio specific flags, but it's
not used to check that we're not exceeding the size of them. Add
such a check.
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The user can set the max_sectors limit to any valid value via sysfs
/sys/block/<dev>/queue/max_sectors_kb attribute. If the device limits
are ever rescanned, though, the limit reverts back to the potentially
artificially low BLK_DEF_MAX_SECTORS value.
Preserve the user's setting as the max_sectors limit as long as it's
valid. The user can reset back to defaults by writing 0 to the sysfs
file.
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20230105205146.3610282-3-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This is used as an unsigned value, so define it that way to avoid
having to cast it.
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20230105205146.3610282-2-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Upon the invocation of its dispatch function, BFQ returns the next I/O
request of the in-service bfq_queue, unless some exception holds. One
such exception is that there is some underutilized actuator, different
from the actuator for which the in-service queue contains I/O, and
that some other bfq_queue happens to contain I/O for such an
actuator. In this case, the next I/O request of the latter bfq_queue,
and not of the in-service bfq_queue, is returned (I/O is injected from
that bfq_queue). To find such an actuator, a linear scan, in
increasing index order, is performed among actuators.
Performing a linear scan entails a prioritization among actuators: an
underutilized actuator may be considered for injection only if all
actuators with a lower index are currently fully utilized, or if there
is no pending I/O for any lower-index actuator that happens to be
underutilized.
This commits breaks this prioritization and tends to distribute
injection uniformly across actuators. This is obtained by adding the
following condition to the linear scan: even if an actuator A is
underutilized, A is however skipped if its load is higher than that of
the next actuator.
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Davide Zini <davidezini2@gmail.com>
Link: https://lore.kernel.org/r/20230103145503.71712-9-paolo.valente@linaro.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The main service scheme of BFQ for sync I/O is serving one sync
bfq_queue at a time, for a while. In particular, BFQ enforces this
scheme when it deems the latter necessary to boost throughput or
to preserve service guarantees. Unfortunately, when BFQ enforces
this policy, only one actuator at a time gets served for a while,
because each bfq_queue contains I/O only for one actuator. The
other actuators may remain underutilized.
Actually, BFQ may serve (inject) extra I/O, taken from other
bfq_queues, in parallel with that of the in-service queue. This
injection mechanism may provide the ground for dealing also with
the above actuator-underutilization problem. Yet BFQ does not take
the actuator load into account when choosing which queue to pick
extra I/O from. In addition, BFQ may happen to inject extra I/O
only when the in-service queue is temporarily empty.
In view of these facts, this commit extends the
injection mechanism in such a way that the latter:
(1) takes into account also the actuator load;
(2) checks such a load on each dispatch, and injects I/O for an
underutilized actuator, if there is one and there is I/O for it.
To perform the check in (2), this commit introduces a load
threshold, currently set to 4. A linear scan of each actuator is
performed, until an actuator is found for which the following two
conditions hold: the load of the actuator is below the threshold,
and there is at least one non-in-service queue that contains I/O
for that actuator. If such a pair (actuator, queue) is found, then
the head request of that queue is returned for dispatch, instead
of the head request of the in-service queue.
We have set the threshold, empirically, to the minimum possible
value for which an actuator is fully utilized, or close to be
fully utilized. By doing so, injected I/O 'steals' as few
drive-queue slots as possibile to the in-service queue. This
reduces as much as possible the probability that the service of
I/O from the in-service bfq_queue gets delayed because of slot
exhaustion, i.e., because all the slots of the drive queue are
filled with I/O injected from other queues (NCQ provides for 32
slots).
This new mechanism also counters actuator underutilization in the
case of asymmetric configurations of bfq_queues. Namely if there
are few bfq_queues containing I/O for some actuators and many
bfq_queues containing I/O for other actuators. Or if the
bfq_queues containing I/O for some actuators have lower weights
than the other bfq_queues.
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Davide Zini <davidezini2@gmail.com>
Link: https://lore.kernel.org/r/20230103145503.71712-8-paolo.valente@linaro.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This patch implements the code to gather the content of the
independent_access_ranges structure from the request_queue and copy
it into the queue's bfq_data. This copy is done at queue initialization.
We copy the access ranges into the bfq_data to avoid taking the queue
lock each time we access the ranges.
This implementation, however, puts a limit to the maximum independent
ranges supported by the scheduler. Such a limit is equal to the constant
BFQ_MAX_ACTUATORS. This limit was placed to avoid the allocation of
dynamic memory.
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Co-developed-by: Rory Chen <rory.c.chen@seagate.com>
Signed-off-by: Rory Chen <rory.c.chen@seagate.com>
Signed-off-by: Federico Gavioli <f.gavioli97@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20230103145503.71712-7-paolo.valente@linaro.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Similarly to sync bfq_queues, also async bfq_queues need to be split
on a per-actuator basis.
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Davide Zini <davidezini2@gmail.com>
Link: https://lore.kernel.org/r/20230103145503.71712-6-paolo.valente@linaro.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When a bfq_queue Q is merged with another queue, several pieces of
information are saved about Q. These pieces are stored in the
bfqq_data field in the bfq_io_cq data structure of the process
associated with Q.
Yet, with a multi-actuator drive, a process may get associated with
multiple bfq_queues: one queue for each of the N actuators. Each of
these queues may undergo a merge. So, the bfq_io_cq data structure
must be able to accommodate the above information for N queues.
This commit solves this problem by turning the bfqq_data scalar field
into an array of N elements (and by changing code so as to handle
this array).
This solution is written under the assumption that bfq_queues
associated with different actuators cannot be cross-merged. This
assumption holds naturally with basic queue merging: the latter is
triggered by spatial locality, and sectors for different actuators are
not close to each other (apart from the corner case of the last
sectors served by a given actuator and the first sectors served by the
next actuator). As for stable cross-merging, the assumption here is
that it is disabled.
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Gabriele Felici <felicigb@gmail.com>
Signed-off-by: Gianmarco Lusvardi <glusvardi@posteo.net>
Signed-off-by: Giulio Barabino <giuliobarabino99@gmail.com>
Signed-off-by: Emiliano Maccaferri <inbox@emilianomaccaferri.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20230103145503.71712-5-paolo.valente@linaro.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
With a multi-actuator drive, a process may get associated with multiple
bfq_queues: one queue for each of the N actuators. So, the bfq_io_cq
data structure must be able to accommodate its per-queue persistent
information for N queues. Currently it stores this information for
just one queue, in several scalar fields.
This is a preparatory commit for moving to accommodating persistent
information for N queues. In particular, this commit packs all the
above scalar fields into a single data structure. Then there is now
only one field, in bfq_io_cq, that stores all the above information. This
scalar field will then be turned into an array by a following commit.
Suggested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Gianmarco Lusvardi <glusvardi@posteo.net>
Signed-off-by: Giulio Barabino <giuliobarabino99@gmail.com>
Signed-off-by: Emiliano Maccaferri <inbox@emilianomaccaferri.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20230103145503.71712-4-paolo.valente@linaro.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If queues associated with different actuators are merged, then control
is lost on each actuator. Therefore some actuator may be
underutilized, and throughput may decrease. This problem cannot occur
with basic queue merging, because the latter is triggered by spatial
locality, and sectors for different actuators are not close to each
other. Yet it may happen with stable merging. To address this issue,
this commit prevents stable merging from occurring among queues
associated with different actuators.
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20230103145503.71712-3-paolo.valente@linaro.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Single-LUN multi-actuator SCSI drives, as well as all multi-actuator
SATA drives appear as a single device to the I/O subsystem [1]. Yet
they address commands to different actuators internally, as a function
of Logical Block Addressing (LBAs). A given sector is reachable by
only one of the actuators. For example, Seagate’s Serial Advanced
Technology Attachment (SATA) version contains two actuators and maps
the lower half of the SATA LBA space to the lower actuator and the
upper half to the upper actuator.
Evidently, to fully utilize actuators, no actuator must be left idle
or underutilized while there is pending I/O for it. The block layer
must somehow control the load of each actuator individually. This
commit lays the ground for allowing BFQ to provide such a per-actuator
control.
BFQ associates an I/O-request sync bfq_queue with each process doing
synchronous I/O, or with a group of processes, in case of queue
merging. Then BFQ serves one bfq_queue at a time. While in service, a
bfq_queue is emptied in request-position order. Yet the same process,
or group of processes, may generate I/O for different actuators. In
this case, different streams of I/O (each for a different actuator)
get all inserted into the same sync bfq_queue. So there is basically
no individual control on when each stream is served, i.e., on when the
I/O requests of the stream are picked from the bfq_queue and
dispatched to the drive.
This commit enables BFQ to control the service of each actuator
individually for synchronous I/O, by simply splitting each sync
bfq_queue into N queues, one for each actuator. In other words, a sync
bfq_queue is now associated to a pair (process, actuator). As a
consequence of this split, the per-queue proportional-share policy
implemented by BFQ will guarantee that the sync I/O generated for each
actuator, by each process, receives its fair share of service.
This is just a preparatory patch. If the I/O of the same process
happens to be sent to different queues, then each of these queues may
undergo queue merging. To handle this event, the bfq_io_cq data
structure must be properly extended. In addition, stable merging must
be disabled to avoid loss of control on individual actuators. Finally,
also async queues must be split. These issues are described in detail
and addressed in next commits. As for this commit, although multiple
per-process bfq_queues are provided, the I/O of each process or group
of processes is still sent to only one queue, regardless of the
actuator the I/O is for. The forwarding to distinct bfq_queues will be
enabled after addressing the above issues.
[1] https://www.linaro.org/blog/budget-fair-queueing-bfq-linux-io-scheduler-optimizations-for-multi-actuator-sata-hard-drives/
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Gabriele Felici <felicigb@gmail.com>
Signed-off-by: Carmine Zaccagnino <carmine@carminezacc.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20230103145503.71712-2-paolo.valente@linaro.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The devnode() callback in struct device_type should not be modifying the
device that is passed into it, so mark it as a const * and propagate the
function signature changes out into all relevant subsystems that use
this callback.
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Alison Schofield <alison.schofield@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Ben Widawsky <bwidawsk@kernel.org>
Cc: Jeremy Kerr <jk@ozlabs.org>
Cc: Joel Stanley <joel@jms.id.au>
Cc: Alistar Popple <alistair@popple.id.au>
Cc: Eddie James <eajames@linux.ibm.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Jilin Yuan <yuanjilin@cdjrlc.com>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Won Chung <wonchung@google.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230111113018.459199-7-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The uevent() callback in struct device_type should not be modifying the
device that is passed into it, so mark it as a const * and propagate the
function signature changes out into all relevant subsystems that use
this callback.
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Andreas Noever <andreas.noever@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Bard Liao <yung-chuan.liao@linux.intel.com>
Cc: Chaitanya Kulkarni <kch@nvidia.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jilin Yuan <yuanjilin@cdjrlc.com>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Mark Gross <markgross@kernel.org>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Maximilian Luz <luzmaximilian@gmail.com>
Cc: Michael Jamet <michael.jamet@intel.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Sanyog Kale <sanyog.r.kale@intel.com>
Cc: Sean Young <sean@mess.org>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Won Chung <wonchung@google.com>
Cc: Yehezkel Bernat <YehezkelShB@gmail.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> # for Thunderbolt
Acked-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Wolfram Sang <wsa@kernel.org>
Acked-by: Vinod Koul <vkoul@kernel.org>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230111113018.459199-6-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'block-6.2-2023-01-20' of git://git.kernel.dk/linux
Pull block fixes from Jens Axboe:
"Various little tweaks all over the place:
- NVMe pull request via Christoph:
- fix controller shutdown regression in nvme-apple (Janne Grunau)
- fix a polling on timeout regression in nvme-pci (Keith Busch)
- Fix a bug in the read request side request allocation caching
(Pavel)
- pktcdvd was brought back after we configured a NULL return on bio
splits, make it consistent with the others (me)
- BFQ refcount fix (Yu)
- Block cgroup policy activation fix (Yu)
- Fix for an md regression introduced in the 6.2 cycle (Adrian)"
* tag 'block-6.2-2023-01-20' of git://git.kernel.dk/linux:
nvme-pci: fix timeout request state check
nvme-apple: only reset the controller when RTKit is running
nvme-apple: reset controller during shutdown
block: fix hctx checks for batch allocation
block/rnbd-clt: fix wrong max ID in ida_alloc_max
blk-cgroup: fix missing pd_online_fn() while activating policy
pktcdvd: check for NULL returna fter calling bio_split_to_limits()
block, bfq: switch 'bfqg->ref' to use atomic refcount apis
md: fix incorrect declaration about claim_rdev in md_import_device
The default queue mapping builder of blk_mq_map_queues doesn't take NUMA
topo into account, so the built mapping is pretty bad, since CPUs
belonging to different NUMA node are assigned to same queue. It is
observed that IOPS drops by ~30% when running two jobs on same hctx
of null_blk from two CPUs belonging to two NUMA nodes compared with
from same NUMA node.
Address the issue by reusing group_cpus_evenly() for building queue mapping
since group_cpus_evenly() does group cpus according to CPU/NUMA locality.
Also performance data becomes more stable with this given correct queue
mapping is applied wrt. numa locality viewpoint, for example, on one two
nodes arm64 machine with 160 cpus, node 0(cpu 0~79), node 1(cpu 80~159):
1) modprobe null_blk nr_devices=1 submit_queues=2
2) run 'fio(t/io_uring -p 0 -n 4 -r 20 /dev/nullb0)', and observe that
IOPS becomes much stable on multiple tests:
- unpatched: IOPS is 2.5M ~ 4.5M
- patched: IOPS is 4.3M ~ 5.0M
Lots of drivers may benefit from the change, such as nvme pci poll,
nvme tcp, ...
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Link: https://lore.kernel.org/r/20221227022905.352674-7-ming.lei@redhat.com
When there are no read queues read requests will be assigned a
default queue on allocation. However, blk_mq_get_cached_request() is not
prepared for that and will fail all attempts to grab read requests from
the cache. Worst case it doubles the number of requests allocated,
roughly half of which will be returned by blk_mq_free_plug_rqs().
It only affects batched allocations and so is io_uring specific.
For reference, QD8 t/io_uring benchmark improves by 20-35%.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/80d4511011d7d4751b4cf6375c4e38f237d935e3.1673955390.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If the policy defines pd_online_fn(), it should be called after
pd_init_fn(), like blkg_create().
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230103112833.2013432-1-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The updating of 'bfqg->ref' should be protected by 'bfqd->lock', however,
during code review, we found that bfq_pd_free() update 'bfqg->ref'
without holding the lock, which is problematic:
1) bfq_pd_free() triggered by removing cgroup is called asynchronously;
2) bfqq will grab bfqg reference, and exit bfqq will drop the reference,
which can concurrent with 1).
Unfortunately, 'bfqd->lock' can't be held here because 'bfqd' might already
be freed in bfq_pd_free(). Fix the problem by using atomic refcount apis.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230103084755.1256479-1-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'block-6.2-2023-01-13' of git://git.kernel.dk/linux
Pull block fixes from Jens Axboe:
"Nothing major in here, just a collection of NVMe fixes and dropping a
wrong might_sleep() that static checkers tripped over but which isn't
valid"
* tag 'block-6.2-2023-01-13' of git://git.kernel.dk/linux:
MAINTAINERS: stop nvme matching for nvmem files
nvme: don't allow unprivileged passthrough on partitions
nvme: replace the "bool vec" arguments with flags in the ioctl path
nvme: remove __nvme_ioctl
nvme-pci: fix error handling in nvme_pci_enable()
nvme-pci: add NVME_QUIRK_IDENTIFY_CNS quirk to Apple T2 controllers
nvme-apple: add NVME_QUIRK_IDENTIFY_CNS quirk to fix regression
block: Drop spurious might_sleep() from blk_put_queue()
Check that the PREFUSH and FUA flags are only set on write bios,
given that the flush state machine expects that.
[Damien] The check is also extended to REQ_OP_ZONE_APPEND operations as
these are data write operations used by btrfs and zonefs and may also
have the REQ_FUA bit set.
Reported-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
This is more efficient than iter_iov.
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
[axboe: fold in iovec assumption fix]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Dan reports the following smatch detected the following:
block/blk-cgroup.c:1863 blkcg_schedule_throttle() warn: sleeping in atomic context
caused by blkcg_schedule_throttle() calling blk_put_queue() in an
non-sleepable context.
blk_put_queue() acquired might_sleep() in 63f93fd6fa ("block: mark
blk_put_queue as potentially blocking") which transferred the might_sleep()
from blk_free_queue().
blk_free_queue() acquired might_sleep() in e8c7d14ac6 ("block: revert back
to synchronous request_queue removal") while turning request_queue removal
synchronous. However, this isn't necessary as nothing in the free path
actually requires sleeping.
It's pretty unusual to require a sleeping context in a put operation and
it's not needed in the first place. Let's drop it.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Dan Carpenter <error27@gmail.com>
Link: https://lkml.kernel.org/r/Y7g3L6fntnTtOm63@kili
Cc: Christoph Hellwig <hch@lst.de>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Fixes: e8c7d14ac6 ("block: revert back to synchronous request_queue removal") # v5.9+
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/Y7iFwjN+XzWvLv3y@slm.duckdns.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'block-2023-01-06' of git://git.kernel.dk/linux
Pull block fixes from Jens Axboe:
"The big change here is obviously the revert of the pktcdvd driver
removal. Outside of that, just minor tweaks. In detail:
- Re-instate the pktcdvd driver, which necessitates adding back
bio_copy_data_iter() and the fops->devnode() hook for now (me)
- Fix for splitting of a bio marked as NOWAIT, causing either nowait
reads or writes to error with EAGAIN even if parts of the IO
completed (me)
- Fix for ublk, punting management commands to io-wq as they can all
easily block for extended periods of time (Ming)
- Removal of SRCU dependency for the block layer (Paul)"
* tag 'block-2023-01-06' of git://git.kernel.dk/linux:
block: Remove "select SRCU"
Revert "pktcdvd: remove driver."
Revert "block: remove devnode callback from struct block_device_operations"
Revert "block: bio_copy_data_iter"
ublk: honor IO_URING_F_NONBLOCK for handling control command
block: don't allow splitting of a REQ_NOWAIT bio
block: handle bio_split_to_limits() NULL return
Now that the SRCU Kconfig option is unconditionally selected, there is
no longer any point in selecting it. Therefore, remove the "select SRCU"
Kconfig statements.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If we split a bio marked with REQ_NOWAIT, then we can trigger spurious
EAGAIN if constituent parts of that split bio end up failing request
allocations. Parts will complete just fine, but just a single failure
in one of the chained bios will yield an EAGAIN final result for the
parent bio.
Return EAGAIN early if we end up needing to split such a bio, which
allows for saner recovery handling.
Cc: stable@vger.kernel.org # 5.15+
Link: https://github.com/axboe/liburing/issues/766
Reported-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This can't happen right now, but in preparation for allowing
bio_split_to_limits() returning NULL if it ended the bio, check for it
in all the callers.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'block-6.2-2022-12-29' of git://git.kernel.dk/linux
Pull block fixes from Jens Axboe:
"Mostly just NVMe, but also a single fixup for BFQ for a regression
that happened during the merge window. In detail:
- NVMe pull requests via Christoph:
- Fix doorbell buffer value endianness (Klaus Jensen)
- Fix Linux vs NVMe page size mismatch (Keith Busch)
- Fix a potential use memory access beyong the allocation limit
(Keith Busch)
- Fix a multipath vs blktrace NULL pointer dereference (Yanjun
Zhang)
- Fix various problems in handling the Command Supported and
Effects log (Christoph Hellwig)
- Don't allow unprivileged passthrough of commands that don't
transfer data but modify logical block content (Christoph
Hellwig)
- Add a features and quirks policy document (Christoph Hellwig)
- Fix some really nasty code that was correct but made smatch
complain (Sagi Grimberg)
- Use-after-free regression in BFQ from this merge window (Yu)"
* tag 'block-6.2-2022-12-29' of git://git.kernel.dk/linux:
nvme-auth: fix smatch warning complaints
nvme: consult the CSE log page for unprivileged passthrough
nvme: also return I/O command effects from nvme_command_effects
nvmet: don't defer passthrough commands with trivial effects to the workqueue
nvmet: set the LBCC bit for commands that modify data
nvmet: use NVME_CMD_EFFECTS_CSUPP instead of open coding it
nvme: fix the NVME_CMD_EFFECTS_CSE_MASK definition
docs, nvme: add a feature and quirk policy document
nvme-pci: update sqsize when adjusting the queue depth
nvme: fix setting the queue depth in nvme_alloc_io_tag_set
block, bfq: fix uaf for bfqq in bfq_exit_icq_bfqq
nvme: fix multipath crash caused by flush request when blktrace is enabled
nvme-pci: fix page size checks
nvme-pci: fix mempool alloc size
nvme-pci: fix doorbell buffer value endianness
Commit 64dc8c732f ("block, bfq: fix possible uaf for 'bfqq->bic'")
will access 'bic->bfqq' in bic_set_bfqq(), however, bfq_exit_icq_bfqq()
can free bfqq first, and then call bic_set_bfqq(), which will cause uaf.
Fix the problem by moving bfq_exit_bfqq() behind bic_set_bfqq().
Fixes: 64dc8c732f ("block, bfq: fix possible uaf for 'bfqq->bic'")
Reported-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20221226030605.1437081-1-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Due to several bugs caused by timers being re-armed after they are
shutdown and just before they are freed, a new state of timers was added
called "shutdown". After a timer is set to this state, then it can no
longer be re-armed.
The following script was run to find all the trivial locations where
del_timer() or del_timer_sync() is called in the same function that the
object holding the timer is freed. It also ignores any locations where
the timer->function is modified between the del_timer*() and the free(),
as that is not considered a "trivial" case.
This was created by using a coccinelle script and the following
commands:
$ cat timer.cocci
@@
expression ptr, slab;
identifier timer, rfield;
@@
(
- del_timer(&ptr->timer);
+ timer_shutdown(&ptr->timer);
|
- del_timer_sync(&ptr->timer);
+ timer_shutdown_sync(&ptr->timer);
)
... when strict
when != ptr->timer
(
kfree_rcu(ptr, rfield);
|
kmem_cache_free(slab, ptr);
|
kfree(ptr);
)
$ spatch timer.cocci . > /tmp/t.patch
$ patch -p1 < /tmp/t.patch
Link: https://lore.kernel.org/lkml/20221123201306.823305113@linutronix.de/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Pavel Machek <pavel@ucw.cz> [ LED ]
Acked-by: Kalle Valo <kvalo@kernel.org> [ wireless ]
Acked-by: Paolo Abeni <pabeni@redhat.com> [ networking ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Merge tag 'block-6.2-2022-12-19' of git://git.kernel.dk/linux
Pull block fixes from Jens Axboe:
- Various fixes for BFQ (Yu, Yuwei)
- Fix for loop command line parsing (Isaac)
- No need to specifically clear REQ_ALLOC_CACHE on IOPOLL downgrade
anymore (me)
- blk-iocost enum fix for newer gcc (Jiri)
- UAF fix for queue release (Ming)
- blk-iolatency error handling memory leak fix (Tejun)
* tag 'block-6.2-2022-12-19' of git://git.kernel.dk/linux:
block: don't clear REQ_ALLOC_CACHE for non-polled requests
block: fix use-after-free of q->q_usage_counter
block, bfq: only do counting of pending-request for BFQ_GROUP_IOSCHED
blk-iolatency: Fix memory leak on add_disk() failures
loop: Fix the max_loop commandline argument treatment when it is set to 0
block/blk-iocost (gcc13): keep large values in a new enum
block, bfq: replace 0/1 with false/true in bic apis
block, bfq: don't return bfqg from __bfq_bic_change_cgroup()
block, bfq: fix possible uaf for 'bfqq->bic'
Here is the set of driver core and kernfs changes for 6.2-rc1.
The "big" change in here is the addition of a new macro,
container_of_const() that will preserve the "const-ness" of a pointer
passed into it.
The "problem" of the current container_of() macro is that if you pass in
a "const *", out of it can comes a non-const pointer unless you
specifically ask for it. For many usages, we want to preserve the
"const" attribute by using the same call. For a specific example, this
series changes the kobj_to_dev() macro to use it, allowing it to be used
no matter what the const value is. This prevents every subsystem from
having to declare 2 different individual macros (i.e.
kobj_const_to_dev() and kobj_to_dev()) and having the compiler enforce
the const value at build time, which having 2 macros would not do
either.
The driver for all of this have been discussions with the Rust kernel
developers as to how to properly mark driver core, and kobject, objects
as being "non-mutable". The changes to the kobject and driver core in
this pull request are the result of that, as there are lots of paths
where kobjects and device pointers are not modified at all, so marking
them as "const" allows the compiler to enforce this.
So, a nice side affect of the Rust development effort has been already
to clean up the driver core code to be more obvious about object rules.
All of this has been bike-shedded in quite a lot of detail on lkml with
different names and implementations resulting in the tiny version we
have in here, much better than my original proposal. Lots of subsystem
maintainers have acked the changes as well.
Other than this change, included in here are smaller stuff like:
- kernfs fixes and updates to handle lock contention better
- vmlinux.lds.h fixes and updates
- sysfs and debugfs documentation updates
- device property updates
All of these have been in the linux-next tree for quite a while with no
problems, OTHER than some merge issues with other trees that should be
obvious when you hit them (block tree deletes a driver that this tree
modifies, iommufd tree modifies code that this tree also touches). If
there are merge problems with these trees, please let me know.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here is the set of driver core and kernfs changes for 6.2-rc1.
The "big" change in here is the addition of a new macro,
container_of_const() that will preserve the "const-ness" of a pointer
passed into it.
The "problem" of the current container_of() macro is that if you pass
in a "const *", out of it can comes a non-const pointer unless you
specifically ask for it. For many usages, we want to preserve the
"const" attribute by using the same call. For a specific example, this
series changes the kobj_to_dev() macro to use it, allowing it to be
used no matter what the const value is. This prevents every subsystem
from having to declare 2 different individual macros (i.e.
kobj_const_to_dev() and kobj_to_dev()) and having the compiler enforce
the const value at build time, which having 2 macros would not do
either.
The driver for all of this have been discussions with the Rust kernel
developers as to how to properly mark driver core, and kobject,
objects as being "non-mutable". The changes to the kobject and driver
core in this pull request are the result of that, as there are lots of
paths where kobjects and device pointers are not modified at all, so
marking them as "const" allows the compiler to enforce this.
So, a nice side affect of the Rust development effort has been already
to clean up the driver core code to be more obvious about object
rules.
All of this has been bike-shedded in quite a lot of detail on lkml
with different names and implementations resulting in the tiny version
we have in here, much better than my original proposal. Lots of
subsystem maintainers have acked the changes as well.
Other than this change, included in here are smaller stuff like:
- kernfs fixes and updates to handle lock contention better
- vmlinux.lds.h fixes and updates
- sysfs and debugfs documentation updates
- device property updates
All of these have been in the linux-next tree for quite a while with
no problems"
* tag 'driver-core-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (58 commits)
device property: Fix documentation for fwnode_get_next_parent()
firmware_loader: fix up to_fw_sysfs() to preserve const
usb.h: take advantage of container_of_const()
device.h: move kobj_to_dev() to use container_of_const()
container_of: add container_of_const() that preserves const-ness of the pointer
driver core: fix up missed drivers/s390/char/hmcdrv_dev.c class.devnode() conversion.
driver core: fix up missed scsi/cxlflash class.devnode() conversion.
driver core: fix up some missing class.devnode() conversions.
driver core: make struct class.devnode() take a const *
driver core: make struct class.dev_uevent() take a const *
cacheinfo: Remove of_node_put() for fw_token
device property: Add a blank line in Kconfig of tests
device property: Rename goto label to be more precise
device property: Move PROPERTY_ENTRY_BOOL() a bit down
device property: Get rid of __PROPERTY_ENTRY_ARRAY_EL*SIZE*()
kernfs: fix all kernel-doc warnings and multiple typos
driver core: pass a const * into of_device_uevent()
kobject: kset_uevent_ops: make name() callback take a const *
kobject: kset_uevent_ops: make filter() callback take a const *
kobject: make kobject_namespace take a const *
...
For blk-mq, queue release handler is usually called after
blk_mq_freeze_queue_wait() returns. However, the
q_usage_counter->release() handler may not be run yet at that time, so
this can cause a use-after-free.
Fix the issue by moving percpu_ref_exit() into blk_free_queue_rcu().
Since ->release() is called with rcu read lock held, it is agreed that
the race should be covered in caller per discussion from the two links.
Reported-by: Zhang Wensheng <zhangwensheng@huaweicloud.com>
Reported-by: Zhong Jinghua <zhongjinghua@huawei.com>
Link: https://lore.kernel.org/linux-block/Y5prfOjyyjQKUrtH@T590/T/#u
Link: https://lore.kernel.org/lkml/Y4%2FmzMd4evRg9yDi@fedora/
Cc: Hillf Danton <hdanton@sina.com>
Cc: Yu Kuai <yukuai3@huawei.com>
Cc: Dennis Zhou <dennis@kernel.org>
Fixes: 2b0d3d3e4f ("percpu_ref: reduce memory footprint of percpu_ref in fast path")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20221215021629.74870-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The 'bfqd->num_groups_with_pending_reqs' is used when
CONFIG_BFQ_GROUP_IOSCHED is enabled, so let the variables and processes
take effect when CONFIG_BFQ_GROUP_IOSCHED is enabled.
Cc: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Yuwei Guan <Yuwei.Guan@zeekrlife.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20221110112622.389332-1-Yuwei.Guan@zeekrlife.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When a gendisk is successfully initialized but add_disk() fails such as when
a loop device has invalid number of minor device numbers specified,
blkcg_init_disk() is called during init and then blkcg_exit_disk() during
error handling. Unfortunately, iolatency gets initialized in the former but
doesn't get cleaned up in the latter.
This is because, in non-error cases, the cleanup is performed by
del_gendisk() calling rq_qos_exit(), the assumption being that rq_qos
policies, iolatency being one of them, can only be activated once the disk
is fully registered and visible. That assumption is true for wbt and iocost,
but not so for iolatency as it gets initialized before add_disk() is called.
It is desirable to lazy-init rq_qos policies because they are optional
features and add to hot path overhead once initialized - each IO has to walk
all the registered rq_qos policies. So, we want to switch iolatency to lazy
init too. However, that's a bigger change. As a fix for the immediate
problem, let's just add an extra call to rq_qos_exit() in blkcg_exit_disk().
This is safe because duplicate calls to rq_qos_exit() become noop's.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: darklight2357@icloud.com
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Fixes: d706751215 ("block: introduce blk-iolatency io controller")
Cc: stable@vger.kernel.org # v4.19+
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/Y5TQ5gm3O4HXrXR3@slm.duckdns.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Since gcc13, each member of an enum has the same type as the enum [1]. And
that is inherited from its members. Provided:
VTIME_PER_SEC_SHIFT = 37,
VTIME_PER_SEC = 1LLU << VTIME_PER_SEC_SHIFT,
...
AUTOP_CYCLE_NSEC = 10LLU * NSEC_PER_SEC,
the named type is unsigned long.
This generates warnings with gcc-13:
block/blk-iocost.c: In function 'ioc_weight_prfill':
block/blk-iocost.c:3037:37: error: format '%u' expects argument of type 'unsigned int', but argument 4 has type 'long unsigned int'
block/blk-iocost.c: In function 'ioc_weight_show':
block/blk-iocost.c:3047:34: error: format '%u' expects argument of type 'unsigned int', but argument 3 has type 'long unsigned int'
So split the anonymous enum with large values to a separate enum, so
that they don't affect other members.
[1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=36113
Cc: Martin Liska <mliska@suse.cz>
Cc: Tejun Heo <tj@kernel.org>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: cgroups@vger.kernel.org
Cc: linux-block@vger.kernel.org
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20221213120826.17446-1-jirislaby@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Our test report a uaf for 'bfqq->bic' in 5.10:
==================================================================
BUG: KASAN: use-after-free in bfq_select_queue+0x378/0xa30
CPU: 6 PID: 2318352 Comm: fsstress Kdump: loaded Not tainted 5.10.0-60.18.0.50.h602.kasan.eulerosv2r11.x86_64 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58-20220320_160524-szxrtosci10000 04/01/2014
Call Trace:
bfq_select_queue+0x378/0xa30
bfq_dispatch_request+0xe8/0x130
blk_mq_do_dispatch_sched+0x62/0xb0
__blk_mq_sched_dispatch_requests+0x215/0x2a0
blk_mq_sched_dispatch_requests+0x8f/0xd0
__blk_mq_run_hw_queue+0x98/0x180
__blk_mq_delay_run_hw_queue+0x22b/0x240
blk_mq_run_hw_queue+0xe3/0x190
blk_mq_sched_insert_requests+0x107/0x200
blk_mq_flush_plug_list+0x26e/0x3c0
blk_finish_plug+0x63/0x90
__iomap_dio_rw+0x7b5/0x910
iomap_dio_rw+0x36/0x80
ext4_dio_read_iter+0x146/0x190 [ext4]
ext4_file_read_iter+0x1e2/0x230 [ext4]
new_sync_read+0x29f/0x400
vfs_read+0x24e/0x2d0
ksys_read+0xd5/0x1b0
do_syscall_64+0x33/0x40
entry_SYSCALL_64_after_hwframe+0x61/0xc6
Commit 3bc5e683c6 ("bfq: Split shared queues on move between cgroups")
changes that move process to a new cgroup will allocate a new bfqq to
use, however, the old bfqq and new bfqq can point to the same bic:
1) Initial state, two process with io in the same cgroup.
Process 1 Process 2
(BIC1) (BIC2)
| Λ | Λ
| | | |
V | V |
bfqq1 bfqq2
2) bfqq1 is merged to bfqq2.
Process 1 Process 2
(BIC1) (BIC2)
| |
\-------------\|
V
bfqq1 bfqq2(coop)
3) Process 1 exit, then issue new io(denoce IOA) from Process 2.
(BIC2)
| Λ
| |
V |
bfqq2(coop)
4) Before IOA is completed, move Process 2 to another cgroup and issue io.
Process 2
(BIC2)
Λ
|\--------------\
| V
bfqq2 bfqq3
Now that BIC2 points to bfqq3, while bfqq2 and bfqq3 both point to BIC2.
If all the requests are completed, and Process 2 exit, BIC2 will be
freed while there is no guarantee that bfqq2 will be freed before BIC2.
Fix the problem by clearing bfqq->bic while bfqq is detached from bic.
Fixes: 3bc5e683c6 ("bfq: Split shared queues on move between cgroups")
Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20221214030430.3304151-1-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'for-6.2/block-2022-12-08' of git://git.kernel.dk/linux
Pull block updates from Jens Axboe:
- NVMe pull requests via Christoph:
- Support some passthrough commands without CAP_SYS_ADMIN (Kanchan
Joshi)
- Refactor PCIe probing and reset (Christoph Hellwig)
- Various fabrics authentication fixes and improvements (Sagi
Grimberg)
- Avoid fallback to sequential scan due to transient issues (Uday
Shankar)
- Implement support for the DEAC bit in Write Zeroes (Christoph
Hellwig)
- Allow overriding the IEEE OUI and firmware revision in configfs
for nvmet (Aleksandr Miloserdov)
- Force reconnect when number of queue changes in nvmet (Daniel
Wagner)
- Minor fixes and improvements (Uros Bizjak, Joel Granados, Sagi
Grimberg, Christoph Hellwig, Christophe JAILLET)
- Fix and cleanup nvme-fc req allocation (Chaitanya Kulkarni)
- Use the common tagset helpers in nvme-pci driver (Christoph
Hellwig)
- Cleanup the nvme-pci removal path (Christoph Hellwig)
- Use kstrtobool() instead of strtobool (Christophe JAILLET)
- Allow unprivileged passthrough of Identify Controller (Joel
Granados)
- Support io stats on the mpath device (Sagi Grimberg)
- Minor nvmet cleanup (Sagi Grimberg)
- MD pull requests via Song:
- Code cleanups (Christoph)
- Various fixes
- Floppy pull request from Denis:
- Fix a memory leak in the init error path (Yuan)
- Series fixing some batch wakeup issues with sbitmap (Gabriel)
- Removal of the pktcdvd driver that was deprecated more than 5 years
ago, and subsequent removal of the devnode callback in struct
block_device_operations as no users are now left (Greg)
- Fix for partition read on an exclusively opened bdev (Jan)
- Series of elevator API cleanups (Jinlong, Christoph)
- Series of fixes and cleanups for blk-iocost (Kemeng)
- Series of fixes and cleanups for blk-throttle (Kemeng)
- Series adding concurrent support for sync queues in BFQ (Yu)
- Series bringing drbd a bit closer to the out-of-tree maintained
version (Christian, Joel, Lars, Philipp)
- Misc drbd fixes (Wang)
- blk-wbt fixes and tweaks for enable/disable (Yu)
- Fixes for mq-deadline for zoned devices (Damien)
- Add support for read-only and offline zones for null_blk
(Shin'ichiro)
- Series fixing the delayed holder tracking, as used by DM (Yu,
Christoph)
- Series enabling bio alloc caching for IRQ based IO (Pavel)
- Series enabling userspace peer-to-peer DMA (Logan)
- BFQ waker fixes (Khazhismel)
- Series fixing elevator refcount issues (Christoph, Jinlong)
- Series cleaning up references around queue destruction (Christoph)
- Series doing quiesce by tagset, enabling cleanups in drivers
(Christoph, Chao)
- Series untangling the queue kobject and queue references (Christoph)
- Misc fixes and cleanups (Bart, David, Dawei, Jinlong, Kemeng, Ye,
Yang, Waiman, Shin'ichiro, Randy, Pankaj, Christoph)
* tag 'for-6.2/block-2022-12-08' of git://git.kernel.dk/linux: (247 commits)
blktrace: Fix output non-blktrace event when blk_classic option enabled
block: sed-opal: Don't include <linux/kernel.h>
sed-opal: allow using IOC_OPAL_SAVE for locking too
blk-cgroup: Fix typo in comment
block: remove bio_set_op_attrs
nvmet: don't open-code NVME_NS_ATTR_RO enumeration
nvme-pci: use the tagset alloc/free helpers
nvme: add the Apple shared tag workaround to nvme_alloc_io_tag_set
nvme: only set reserved_tags in nvme_alloc_io_tag_set for fabrics controllers
nvme: consolidate setting the tagset flags
nvme: pass nr_maps explicitly to nvme_alloc_io_tag_set
block: bio_copy_data_iter
nvme-pci: split out a nvme_pci_ctrl_is_dead helper
nvme-pci: return early on ctrl state mismatch in nvme_reset_work
nvme-pci: rename nvme_disable_io_queues
nvme-pci: cleanup nvme_suspend_queue
nvme-pci: remove nvme_pci_disable
nvme-pci: remove nvme_disable_admin_queue
nvme: merge nvme_shutdown_ctrl into nvme_disable_ctrl
nvme: use nvme_wait_ready in nvme_shutdown_ctrl
...
This release adds SM4 encryption support, contributed by Tianjia Zhang.
SM4 is a Chinese block cipher that is an alternative to AES.
I recommend against using SM4, but (according to Tianjia) some people
are being required to use it. Since SM4 has been turning up in many
other places (crypto API, wireless, TLS, OpenSSL, ARMv8 CPUs, etc.), it
hasn't been very controversial, and some people have to use it, I don't
think it would be fair for me to reject this optional feature.
Besides the above, there are a couple cleanups.
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Merge tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt
Pull fscrypt updates from Eric Biggers:
"This release adds SM4 encryption support, contributed by Tianjia
Zhang. SM4 is a Chinese block cipher that is an alternative to AES.
I recommend against using SM4, but (according to Tianjia) some people
are being required to use it. Since SM4 has been turning up in many
other places (crypto API, wireless, TLS, OpenSSL, ARMv8 CPUs, etc.),
it hasn't been very controversial, and some people have to use it, I
don't think it would be fair for me to reject this optional feature.
Besides the above, there are a couple cleanups"
* tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt:
fscrypt: add additional documentation for SM4 support
fscrypt: remove unused Speck definitions
fscrypt: Add SM4 XTS/CTS symmetric algorithm support
blk-crypto: Add support for SM4-XTS blk crypto mode
fscrypt: add comment for fscrypt_valid_enc_modes_v1()
fscrypt: pass super_block to fscrypt_put_master_key_activeref()
Usually when closing a crypto device (eg: dm-crypt with LUKS) the
volume key is not required, as it requires root privileges anyway, and
root can deny access to a disk in many ways regardless. Requiring the
volume key to lock the device is a peculiarity of the OPAL
specification.
Given we might already have saved the key if the user requested it via
the 'IOC_OPAL_SAVE' ioctl, we can use that key to lock the device if no
key was provided here and the locking range matches, and the user sets
the appropriate flag with 'IOC_OPAL_SAVE'. This allows integrating OPAL
with tools and libraries that are used to the common behaviour and do
not ask for the volume key when closing a device.
Callers can always pass a non-zero key and it will be used regardless,
as before.
Suggested-by: Štěpán Horáček <stepan.horacek@gmail.com>
Signed-off-by: Luca Boccassi <bluca@debian.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20221206092913.4625-1-luca.boccassi@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
With the pktcdvdv removal, bio_copy_data_iter is unused now. Fold the
logic into bio_copy_data and remove the separate lower level function.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221206144407.722049-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There is no need to update tg->slice_start[rw] to start when they are
equal already. So remove "eq" part of check before update slice_start.
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Link: https://lore.kernel.org/r/20221205115709.251489-10-shikemeng@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There is no need to check elapsed time from last upgrade for each node in
hierarchy. Move this check before traversing as throtl_can_upgrade do
to remove repeat check.
Reported-by: kernel test robot <lkp@intel.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Link: https://lore.kernel.org/r/20221205115709.251489-9-shikemeng@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Function tg_last_low_overflow_time is called with intermediate node as
following:
throtl_hierarchy_can_downgrade
throtl_tg_can_downgrade
tg_last_low_overflow_time
throtl_hierarchy_can_upgrade
throtl_tg_can_upgrade
tg_last_low_overflow_time
throtl_hierarchy_can_downgrade/throtl_hierarchy_can_upgrade will traverse
from leaf node to sub-root node and pass traversed intermediate node
to tg_last_low_overflow_time.
No such limit could be found from context and implementation of
tg_last_low_overflow_time, so remove this limit in comment.
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Link: https://lore.kernel.org/r/20221205115709.251489-8-shikemeng@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Commit c79892c557 ("blk-throttle: add upgrade logic for LIMIT_LOW
state") added upgrade logic for low limit and methioned that
1. "To determine if a cgroup exceeds its limitation, we check if the cgroup
has pending request. Since cgroup is throttled according to the limit,
pending request means the cgroup reaches the limit."
2. "If a cgroup has limit set for both read and write, we consider the
combination of them for upgrade. The reason is read IO and write IO can
interfere with each other. If we do the upgrade based in one direction IO,
the other direction IO could be severly harmed."
Besides, we also determine that cgroup reaches low limit if low limit is 0,
see comment in throtl_tg_can_upgrade.
Collect the information above, the desgin of upgrade check is as following:
1.The low limit is reached if limit is zero or io is already queued.
2.Cgroup will pass upgrade check if low limits of READ and WRITE are both
reached.
Simpfy the check code described above to removce repeat check and improve
readability. There is no functional change.
Detail equivalence proof is as following:
All replaced conditions to return true are as following:
condition 1
(!read_limit && !write_limit)
condition 2
read_limit && sq->nr_queued[READ] &&
(!write_limit || sq->nr_queued[WRITE])
condition 3
write_limit && sq->nr_queued[WRITE] &&
(!read_limit || sq->nr_queued[READ])
Transferring condition 2 as following:
(read_limit && sq->nr_queued[READ]) &&
(!write_limit || sq->nr_queued[WRITE])
is equivalent to
(read_limit && sq->nr_queued[READ]) &&
(!write_limit || (write_limit && sq->nr_queued[WRITE]))
is equivalent to
condition 2.1
(read_limit && sq->nr_queued[READ] &&
!write_limit) ||
condition 2.2
(read_limit && sq->nr_queued[READ] &&
(write_limit && sq->nr_queued[WRITE]))
Transferring condition 3 as following:
write_limit && sq->nr_queued[WRITE] &&
(!read_limit || sq->nr_queued[READ])
is equivalent to
(write_limit && sq->nr_queued[WRITE]) &&
(!read_limit || (read_limit && sq->nr_queued[READ]))
is equivalent to
condition 3.1
((write_limit && sq->nr_queued[WRITE]) &&
!read_limit) ||
condition 3.2
((write_limit && sq->nr_queued[WRITE]) &&
(read_limit && sq->nr_queued[READ]))
Condition 3.2 is the same as condition 2.2, so all conditions we get to
return are as following:
(!read_limit && !write_limit) (1)
(!read_limit && (write_limit && sq->nr_queued[WRITE])) (3.1)
((read_limit && sq->nr_queued[READ]) && !write_limit) (2.1)
((write_limit && sq->nr_queued[WRITE]) &&
(read_limit && sq->nr_queued[READ])) (2.2)
As we can extract conditions "(a1 || a2) && (b1 || b2)" to:
a1 && b1
a1 && b2
a2 && b1
ab && b2
Considering that:
a1 = !read_limit
a2 = read_limit && sq->nr_queued[READ]
b1 = !write_limit
b2 = write_limit && sq->nr_queued[WRITE]
We can pack replaced conditions to
(!read_limit || (read_limit && sq->nr_queued[READ])) &&
(!write_limit || (write_limit && sq->nr_queued[WRITE]))
which is equivalent to
(!read_limit || sq->nr_queued[READ]) &&
(!write_limit || sq->nr_queued[WRITE])
Reported-by: kernel test robot <lkp@intel.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Link: https://lore.kernel.org/r/20221205115709.251489-6-shikemeng@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In C language, When executing "if (expression1 && expression2)" and
expression1 return false, the expression2 may not be executed.
For "tg_within_bps_limit(tg, bio, bps_limit, &bps_wait) &&
tg_within_iops_limit(tg, bio, iops_limit, &iops_wait))", if bps is
limited, tg_within_bps_limit will return false and
tg_within_iops_limit will not be called. So even bps and iops are
both limited, iops_wait will not be calculated and is always zero.
So wait time of iops is always ignored.
Fix this by always calling tg_within_bps_limit and tg_within_iops_limit
to get wait time for both bps and iops.
Observed that:
1. Wait time in tg_within_iops_limit/tg_within_bps_limit need always
be stored as wait argument is always passed.
2. wait time is stored to zero if iops/bps is limited otherwise non-zero
is stored.
Simpfy tg_within_iops_limit/tg_within_bps_limit by removing wait argument
and return wait time directly. Caller tg_may_dispatch checks if wait time
is zero to find if iops/bps is limited.
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Link: https://lore.kernel.org/r/20221205115709.251489-5-shikemeng@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Ignore cgroup without io queued in blk_throtl_cancel_bios for two
reasons:
1. Save cpu cycle for trying to dispatch cgroup which is no io queued.
2. Avoid non-consistent state that cgroup is inserted to service queue
without THROTL_TG_PENDING set as tg_update_disptime will unconditional
re-insert cgroup to service queue. If we are on the default hierarchy,
IO dispatched from child in tg_dispatch_one_bio will trigger inserting
cgroup to service queue without erase first and ruin the tree.
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Link: https://lore.kernel.org/r/20221205115709.251489-4-shikemeng@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Consider situation as following (on the default hierarchy):
HDD
|
root (bps limit: 4k)
|
child (bps limit :8k)
|
fio bs=8k
Rate of fio is supposed to be 4k, but result is 8k. Reason is as
following:
Size of single IO from fio is larger than bytes allowed in one
throtl_slice in child, so IOs are always queued in child group first.
When queued IOs in child are dispatched to parent group, BIO_BPS_THROTTLED
is set and these IOs will not be limited by tg_within_bps_limit anymore.
Fix this by only set BIO_BPS_THROTTLED when the bio traversed the entire
tree.
There patch has no influence on situation which is not on the default
hierarchy as each group is a single root group without parent.
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Link: https://lore.kernel.org/r/20221205115709.251489-3-shikemeng@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
On the default hierarchy (cgroup2), the throttle interface files don't
exist in the root cgroup, so the ablity to limit the whole system
by configuring root group is not existing anymore. In general, cgroup
doesn't wanna be in the business of restricting resources at the
system level, so correct the stale comment that we can limit whole
system to we can only limit subtree.
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Link: https://lore.kernel.org/r/20221205115709.251489-2-shikemeng@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
With the removal of the pktcdvd driver, there are no in-kernel users of
the devnode callback in struct block_device_operations, so it can be
safely removed. If it is needed for new block drivers in the future, it
can be brought back.
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20221203140747.1942969-1-gregkh@linuxfoundation.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Make the description of @gendisk to @disk in blkcg_schedule_throttle()
to clear the below warnings:
block/blk-cgroup.c:1850: warning: Function parameter or member 'disk' not described in 'blkcg_schedule_throttle'
block/blk-cgroup.c:1850: warning: Excess function parameter 'gendisk' description in 'blkcg_schedule_throttle'
Fixes: de185b56e8 ("blk-cgroup: pass a gendisk to blkcg_schedule_throttle")
Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=3338
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Link: https://lore.kernel.org/r/20221202011713.14834-1-yang.lee@linux.alibaba.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
SM4 is a symmetric cipher algorithm widely used in China. The SM4-XTS
variant is used to encrypt length-preserving data. This is the
mandatory algorithm in some special scenarios.
Add support for the algorithm to block inline encryption. This is needed
for the inlinecrypt mount option to be supported via
blk-crypto-fallback, as it is for the other fscrypt modes.
Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20221201125819.36932-2-tianjia.zhang@linux.alibaba.com
Use only one hyphen in kernel-doc notation between the function name
and its short description.
The is the documented kerenl-doc format. It also fixes the HTML
presentation to be consistent with other functions.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Link: https://lore.kernel.org/r/20221201070331.25685-1-rdunlap@infradead.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There is no iocg_pd_init function. The pd_alloc_fn function pointer of
iocost policy is set with ioc_pd_init. Just correct it.
Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20221018121932.10792-6-shikemeng@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If we trace vtime_base_rate instead of vtime_rate, there is nowhere
which accesses now->vrate except function ioc_now using now->vrate locally.
Just remove it.
Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20221018121932.10792-5-shikemeng@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Since commit ac33e91e2d ("blk-iocost: implement vtime loss
compensation") rename original vtime_rate to vtime_base_rate
and current vtime_rate is original vtime_rate with compensation.
The current rate showed in tracepoint is mixed with vtime_rate
and vtime_base_rate:
1) In function ioc_adjust_base_vrate, the first trace_iocost_ioc_vrate_adj
shows vtime_rate, the second trace_iocost_ioc_vrate_adj shows
vtime_base_rate.
2) In function iocg_activate shows vtime_rate by calling
TRACE_IOCG_PATH(iocg_activate...
3) In function ioc_check_iocgs shows vtime_rate by calling
TRACE_IOCG_PATH(iocg_idle...
Trace vtime_base_rate instead of vtime_rate as:
1) Before commit ac33e91e2d ("blk-iocost: implement vtime loss
compensation"), the traced rate is without compensation, so still
show rate without compensation.
2) The vtime_base_rate is more stable while vtime_rate heavily depends on
excess budeget on current period which may change abruptly in next period.
Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20221018121932.10792-4-shikemeng@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Since commit ac33e91e2daca("blk-iocost: implement vtime loss compensation")
split vtime_rate into vtime_rate and vtime_base_rate, we need reset both
vtime_base_rate and vtime_rate when device parameters are refreshed.
If vtime_base_rate is no reset here, vtime_rate will be overwritten with
old vtime_base_rate soon in ioc_refresh_vrate.
Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20221018121932.10792-3-shikemeng@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Since commit 10c70d95c0 ("block: remove the bd_openers checks in
blk_drop_partitions") we allow rereading of partition table although
there are users of the block device. This has an undesirable consequence
that e.g. if sda and sdb are assembled to a RAID1 device md0 with
partitions, BLKRRPART ioctl on sda will rescan partition table and
create sda1 device. This partition device under a raid device confuses
some programs (such as libstorage-ng used for initial partitioning for
distribution installation) leading to failures.
Fix the problem refusing to rescan partitions if there is another user
that has the block device exclusively open.
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20221130135344.2ul4cyfstfs3znxg@quack3
Fixes: 10c70d95c0 ("block: remove the bd_openers checks in blk_drop_partitions")
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20221130175653.24299-1-jack@suse.cz
[axboe: fold in followup fix]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We can't just say that the last reference release may block, as any
reference dropped could be the last one. So move the might_sleep() from
blk_free_queue to blk_put_queue and update the documentation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221114042637.1009333-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The kobject embedded into the request_queue is used for the queue
directory in sysfs, but that is a child of the gendisks directory and is
intimately tied to it. Move this kobject to the gendisk and use a
refcount_t in the request_queue for the actual request_queue refcounting
that is completely unrelated to the device model.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221114042637.1009333-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk_register_queue fails to handle errors from blk_mq_sysfs_register,
leaks various resources on errors and accidentally sets queue refs percpu
refcount to percpu mode on kobject_add failure. Fix all that by
properly unwinding on errors.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221114042637.1009333-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Split the debugfs removal from blk_unregister_queue into a helper so that
the it can be reused for blk_register_queue error handling.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221114042637.1009333-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Prepare for changes to the block layer sysfs handling by passing the
readily available gendisk to blk_crypto_sysfs_{,un}register.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20221114042637.1009333-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Rename deadline_is_seq_writes() to deadline_is_seq_write() (remove the
"s" plural) to more correctly reflect the fact that this function tests
a single request, not multiple requests.
Fixes: 015d02f485 ("block: mq-deadline: Do not break sequential write streams to zoned HDDs")
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Link: https://lore.kernel.org/r/20221126025550.967914-2-damien.lemoal@opensource.wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'block-6.1-2022-11-25' of git://git.kernel.dk/linux
Pull block fixes from Jens Axboe:
- A few fixes for s390 sads (Stefan, Colin)
- Ensure that ublk doesn't reorder requests, as that can be problematic
on devices that need specific ordering (Ming)
- Fix a queue reference leak in disk allocation handling (Christoph)
* tag 'block-6.1-2022-11-25' of git://git.kernel.dk/linux:
ublk_drv: don't forward io commands in reserve order
s390/dasd: fix possible buffer overflow in copy_pair_show
s390/dasd: fix no record found for raw_track_access
s390/dasd: increase printing of debug data payload
s390/dasd: Fix spelling mistake "Ivalid" -> "Invalid"
blk-mq: fix queue reference leak on blk_mq_alloc_disk_for_queue failure
The devnode() in struct class should not be modifying the device that is
passed into it, so mark it as a const * and propagate the function
signature changes out into all relevant subsystems that use this
callback.
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: x86@kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Justin Sanders <justin@coraid.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Benjamin Gaignard <benjamin.gaignard@collabora.com>
Cc: Liam Mark <lmark@codeaurora.org>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Brian Starkey <Brian.Starkey@arm.com>
Cc: John Stultz <jstultz@google.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Sean Young <sean@mess.org>
Cc: Frank Haverkamp <haver@linux.ibm.com>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.com>
Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Xie Yongji <xieyongji@bytedance.com>
Cc: Gautam Dawar <gautam.dawar@xilinx.com>
Cc: Dan Carpenter <error27@gmail.com>
Cc: Eli Cohen <elic@nvidia.com>
Cc: Parav Pandit <parav@nvidia.com>
Cc: Maxime Coquelin <maxime.coquelin@redhat.com>
Cc: alsa-devel@alsa-project.org
Cc: dri-devel@lists.freedesktop.org
Cc: kvm@vger.kernel.org
Cc: linaro-mm-sig@lists.linaro.org
Cc: linux-block@vger.kernel.org
Cc: linux-input@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-media@vger.kernel.org
Cc: linux-rdma@vger.kernel.org
Cc: linux-scsi@vger.kernel.org
Cc: linux-usb@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Link: https://lore.kernel.org/r/20221123122523.1332370-2-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The dev_uevent() in struct class should not be modifying the device that
is passed into it, so mark it as a const * and propagate the function
signature changes out into all relevant subsystems that use this
callback.
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Russ Weight <russell.h.weight@intel.com>
Cc: Jean Delvare <jdelvare@suse.com>
Cc: Johan Hovold <johan@kernel.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Keith Busch <kbusch@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc: Raed Salem <raeds@nvidia.com>
Cc: Chen Zhongjin <chenzhongjin@huawei.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Avihai Horon <avihaih@nvidia.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Colin Ian King <colin.i.king@gmail.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Jakob Koschel <jakobkoschel@gmail.com>
Cc: Antoine Tenart <atenart@kernel.org>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Wang Yufen <wangyufen@huawei.com>
Cc: linux-block@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-media@vger.kernel.org
Cc: linux-nvme@lists.infradead.org
Cc: linux-pm@vger.kernel.org
Cc: linux-rdma@vger.kernel.org
Cc: linux-usb@vger.kernel.org
Cc: linux-wireless@vger.kernel.org
Cc: netdev@vger.kernel.org
Acked-by: Sebastian Reichel <sre@kernel.org>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Link: https://lore.kernel.org/r/20221123122523.1332370-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mq-deadline ensures an in order dispatching of write requests to zoned
block devices using a per zone lock (a bit). This implies that for any
purely sequential write workload, the drive is exercised most of the
time at a maximum queue depth of one.
However, when such sequential write workload crosses a zone boundary
(when sequentially writing multiple contiguous zones), zone write
locking may prevent the last write to one zone to be issued (as the
previous write is still being executed) but allow the first write to the
following zone to be issued (as that zone is not yet being writen and
not locked). This result in an out of order delivery of the sequential
write commands to the device every time a zone boundary is crossed.
While such behavior does not break the sequential write constraint of
zoned block devices (and does not generate any write error), some zoned
hard-disks react badly to seeing these out of order writes, resulting in
lower write throughput.
This problem can be addressed by always dispatching the first request
of a stream of sequential write requests, regardless of the zones
targeted by these sequential writes. To do so, the function
deadline_skip_seq_writes() is introduced and used in
deadline_next_request() to select the next write command to issue if the
target device is an HDD (blk_queue_nonrot() being false).
deadline_fifo_request() is modified using the new
deadline_earlier_request() and deadline_is_seq_write() helpers to ignore
requests in the fifo list that have a preceding request in lba order
that is sequential.
With this fix, a sequential write workload executed with the following
fio command:
fio --name=seq-write --filename=/dev/sda --zonemode=zbd --direct=1 \
--size=68719476736 --ioengine=libaio --iodepth=32 --rw=write \
--bs=65536
results in an increase from 225 MB/s to 250 MB/s of the write throughput
of an SMR HDD (11% increase).
Cc: <stable@vger.kernel.org>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20221124021208.242541-3-damien.lemoal@opensource.wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
dd_finish_request() tests if the per prio fifo_list is not empty to
determine if request dispatching must be restarted for handling blocked
write requests to zoned devices with a call to
blk_mq_sched_mark_restart_hctx(). While simple, this implementation has
2 problems:
1) Only the priority level of the completed request is considered.
However, writes to a zone may be blocked due to other writes to the
same zone using a different priority level. While this is unlikely to
happen in practice, as writing a zone with different IO priorirites
does not make sense, nothing in the code prevents this from
happening.
2) The use of list_empty() is dangerous as dd_finish_request() does not
take dd->lock and may run concurrently with the insert and dispatch
code.
Fix these 2 problems by testing the write fifo list of all priority
levels using the new helper dd_has_write_work(), and by testing each
fifo list using list_empty_careful().
Fixes: c807ab520f ("block/mq-deadline: Add I/O priority support")
Cc: <stable@vger.kernel.org>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20221124021208.242541-2-damien.lemoal@opensource.wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Allow the compiler to verify consistency of function declarations and
function definitions. This patch fixes the following sparse errors:
block/blk-crypto-profile.c:241:14: error: no previous prototype for ‘blk_crypto_get_keyslot’ [-Werror=missing-prototypes]
241 | blk_status_t blk_crypto_get_keyslot(struct blk_crypto_profile *profile,
| ^~~~~~~~~~~~~~~~~~~~~~
block/blk-crypto-profile.c:318:6: error: no previous prototype for ‘blk_crypto_put_keyslot’ [-Werror=missing-prototypes]
318 | void blk_crypto_put_keyslot(struct blk_crypto_keyslot *slot)
| ^~~~~~~~~~~~~~~~~~~~~~
block/blk-crypto-profile.c:344:6: error: no previous prototype for ‘__blk_crypto_cfg_supported’ [-Werror=missing-prototypes]
344 | bool __blk_crypto_cfg_supported(struct blk_crypto_profile *profile,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
block/blk-crypto-profile.c:373:5: error: no previous prototype for ‘__blk_crypto_evict_key’ [-Werror=missing-prototypes]
373 | int __blk_crypto_evict_key(struct blk_crypto_profile *profile,
| ^~~~~~~~~~~~~~~~~~~~~~
Cc: Eric Biggers <ebiggers@google.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20221123172923.434339-1-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Drop the request queue reference just acquired when __alloc_disk_node
failed.
Fixes: 6f8191fdf4 ("block: simplify disk shutdown")
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Link: https://lore.kernel.org/r/20221122072753.426077-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The commit ee9d55210c ("blk-mq: simplify blk_mq_realloc_tag_set_tags")
cleaned up the function blk_mq_realloc_tag_set_tags. After this change,
the function does not update nr_hw_queues of struct blk_mq_tag_set when
new nr_hw_queues value is smaller than original. This results in failure
of queue number change of block devices. To avoid the failure, add the
missing nr_hw_queues update.
Fixes: ee9d55210c ("blk-mq: simplify blk_mq_realloc_tag_set_tags")
Reported-by: Chaitanya Kulkarni <chaitanyak@nvidia.com>
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Link: https://lore.kernel.org/linux-block/20221118140640.featvt3fxktfquwh@shindev/
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221122084917.2034220-1-shinichiro.kawasaki@wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk_crypto_get_keyslot, blk_crypto_put_keyslot, __blk_crypto_evict_key
and __blk_crypto_cfg_supported are only used internally by the
blk-crypto code, so move the out of blk-crypto-profile.h, which is
included by drivers that supply blk-crypto functionality.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20221114042944.1009870-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add a blk_crypto_config_supported_natively helper that wraps
__blk_crypto_cfg_supported to retrieve the crypto_profile from the
request queue. With this fscrypt can stop including
blk-crypto-profile.h and rely on the public consumer interface in
blk-crypto.h.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20221114042944.1009870-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Switch all public blk-crypto interfaces to use struct block_device
arguments to specify the device they operate on instead of th
request_queue, which is a block layer implementation detail.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20221114042944.1009870-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'block-6.1-2022-11-18' of git://git.kernel.dk/linux
Pull block fixes from Jens Axboe:
- NVMe pull request via Christoph:
- Two more bogus nid quirks (Bean Huo, Tiago Dias Ferreira)
- Memory leak fix in nvmet (Sagi Grimberg)
- Regression fix for block cgroups pinning the wrong blkcg, causing
leaks of cgroups and blkcgs (Chris)
- UAF fix for drbd setup error handling (Dan)
- Fix DMA alignment propagation in DM (Keith)
* tag 'block-6.1-2022-11-18' of git://git.kernel.dk/linux:
dm-log-writes: set dma_alignment limit in io_hints
dm-integrity: set dma_alignment limit in io_hints
block: make blk_set_default_limits() private
dm-crypt: provide dma_alignment limit in io_hints
block: make dma_alignment a stacking queue_limit
nvmet: fix a memory leak in nvmet_auth_set_key
nvme-pci: add NVME_QUIRK_BOGUS_NID for Netac NV7000
drbd: use after free in drbd_create_device()
nvme-pci: add NVME_QUIRK_BOGUS_NID for Micron Nitro
blk-cgroup: properly pin the parent in blkcg_css_online
As noted by Michal, the blkg_iostat_set's in the lockless list
hold reference to blkg's to protect against their removal. Those
blkg's hold reference to blkcg. When a cgroup is being destroyed,
cgroup_rstat_flush() is only called at css_release_work_fn() which is
called when the blkcg reference count reaches 0. This circular dependency
will prevent blkcg from being freed until some other events cause
cgroup_rstat_flush() to be called to flush out the pending blkcg stats.
To prevent this delayed blkcg removal, add a new cgroup_rstat_css_flush()
function to flush stats for a given css and cpu and call it at the blkgs
destruction path, blkcg_destroy_blkgs(), whenever there are still some
pending stats to be flushed. This will ensure that blkcg reference
count can reach 0 ASAP.
Signed-off-by: Waiman Long <longman@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20221105005902.407297-4-longman@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
For a system with many CPUs and block devices, the time to do
blkcg_rstat_flush() from cgroup_rstat_flush() can be rather long. It
can be especially problematic as interrupt is disabled during the flush.
It was reported that it might take seconds to complete in some extreme
cases leading to hard lockup messages.
As it is likely that not all the percpu blkg_iostat_set's has been
updated since the last flush, those stale blkg_iostat_set's don't need
to be flushed in this case. This patch optimizes blkcg_rstat_flush()
by keeping a lockless list of recently updated blkg_iostat_set's in a
newly added percpu blkcg->lhead pointer.
The blkg_iostat_set is added to a lockless list on the update side
in blk_cgroup_bio_start(). It is removed from the lockless list when
flushed in blkcg_rstat_flush(). Due to racing, it is possible that
blk_iostat_set's in the lockless list may have no new IO stats to be
flushed, but that is OK.
To protect against destruction of blkg, a percpu reference is gotten
when putting into the lockless list and put back when removed.
When booting up an instrumented test kernel with this patch on a
2-socket 96-thread system with cgroup v2, out of the 2051 calls to
cgroup_rstat_flush() after bootup, 1788 of the calls were exited
immediately because of empty lockless list. After an all-cpu kernel
build, the ratio became 6295424/6340513. That was more than 99%.
Signed-off-by: Waiman Long <longman@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20221105005902.407297-3-longman@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
For blkcg_css_alloc(), the only error that will be returned is -ENOMEM.
Simplify error handling code by returning this error directly instead
of setting an intermediate "ret" variable.
Signed-off-by: Waiman Long <longman@redhat.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20221105005902.407297-2-longman@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Device mappers had always been getting the default 511 dma mask, but
the underlying device might have a larger alignment requirement. Since
this value is used to determine alloweable direct-io alignment, this
needs to be a stackable limit.
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221110184501.2451620-2-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We hold a reference to the holder kobject for each bd_holder_disk,
so to make the code a bit more robust, use a reference to it instead
of the block_device. As long as no one clears ->bd_holder_dir in
before freeing the disk, this isn't strictly required, but it does
make the code more clear and more robust.
Orignally-From: Christoph Hellwig <hch@lst.de>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221115141054.1051801-10-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently, the caller of bd_link_disk_holer() get 'bdev' by
blkdev_get_by_dev(), which will look up 'bdev' by inode number 'dev'.
Howerver, it's possible that del_gendisk() can be called currently, and
'bd_holder_dir' can be freed before bd_link_disk_holer() access it, thus
use after free is triggered.
t1: t2:
bdev = blkdev_get_by_dev
del_gendisk
kobject_put(bd_holder_dir)
kobject_free()
bd_link_disk_holder
Fix the problem by checking disk is still live and grabbing a reference
to 'bd_holder_dir' first in bd_link_disk_holder().
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221115141054.1051801-9-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Now that dm has been fixed to track of holder registrations before
add_disk, the somewhat buggy block layer code can be safely removed.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20221115141054.1051801-8-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Zero out the pointer to ->slave_dir so that the holder code doesn't
incorrectly treat the object as alive when add_disk failed or after
del_gendisk was called.
Fixes: 89f871af1b ("dm: delay registering the gendisk")
Reported-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Mike Snitzer <snitzer@kernel.org>
Link: https://lore.kernel.org/r/20221115141054.1051801-2-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
While the block device code should switch to implementing
->writepages instead of ->writepage eventually, the current
implementation is entirely pointless as it does the same looping over
->writepage as the generic code if no ->writepages is present.
Remove blkdev_writepages so that we can eventually unexport
generic_writepages.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221116132035.2192924-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This patch extends REQ_ALLOC_CACHE to IRQ completions, whenever
currently it's only limited to iopoll. Instead of guarding the list with
irq toggling on alloc, which is expensive, it keeps an additional
irq-safe list from which bios are spliced in batches to ammortise
overhead. On the put side it toggles irqs, but in many cases they're
already disabled and so cheap.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/c2306de96b900ab9264f4428ec37768ddcf0da36.1667384020.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Biosets keep a mempool, so as long as requests complete we can always
can allocate and have forward progress. Percpu bio caches break that
assumptions as we may complete into the cache of one CPU and after try
and fail to allocate with another CPU. We also can't grab from another
CPU's cache without tricky sync.
If we're allocating with a bio while the mempool is undersaturated,
remove REQ_ALLOC_CACHE flag, so on put it will go straight to mempool.
It might try to free into mempool more requests than required, but
assuming than there is no memory starvation in the system it'll
stabilise and never hit that path.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/aa150caf9c263fa92269e86d7826cc8fa65f38de.1667384020.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blkcg_css_online is supposed to pin the blkcg of the parent, but
397c9f46ee refactored things and along the way, changed it to pin the
css instead. This results in extra pins, and we end up leaking blkcgs
and cgroups.
Fixes: 397c9f46ee ("blk-cgroup: move blkcg_{pin,unpin}_online out of line")
Signed-off-by: Chris Mason <clm@fb.com>
Spotted-by: Rik van Riel <riel@surriel.com>
Cc: <stable@vger.kernel.org> # v5.19+
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lore.kernel.org/r/20221114181930.2093706-1-clm@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Use set->nr_hw_queues for the current number of tags, and remove the
duplicate set->nr_hw_queues update in the caller.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221109100811.2413423-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There is no point in trying to share any code with the realloc case when
all that is needed by the initial tagset allocation is a simple
kcalloc_node.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221109100811.2413423-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
oom_bfqq is just a fallback bfqq, so shouldn't be used with waker
detection.
Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Khazhismel Kumykov <khazhy@google.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20221108181030.1611703-2-khazhy@google.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This fixes crashes in bfq_add_bfqq_busy due to waker_bfqq being NULL,
but woken_list_node still being hashed. This would happen when
bfq_init_rq() expects a brand new allocated queue to be returned from
bfq_get_bfqq_handle_split() and unconditionally updates waker_bfqq
without resetting woken_list_node. Since we can always return oom_bfqq
when attempting to allocate, we cannot assume waker_bfqq starts as NULL.
Avoid setting woken_bfqq for oom_bfqq entirely, as it's not useful.
Crashes would have a stacktrace like:
[160595.656560] bfq_add_bfqq_busy+0x110/0x1ec
[160595.661142] bfq_add_request+0x6bc/0x980
[160595.666602] bfq_insert_request+0x8ec/0x1240
[160595.671762] bfq_insert_requests+0x58/0x9c
[160595.676420] blk_mq_sched_insert_request+0x11c/0x198
[160595.682107] blk_mq_submit_bio+0x270/0x62c
[160595.686759] __submit_bio_noacct_mq+0xec/0x178
[160595.691926] submit_bio+0x120/0x184
[160595.695990] ext4_mpage_readpages+0x77c/0x7c8
[160595.701026] ext4_readpage+0x60/0xb0
[160595.705158] filemap_read_page+0x54/0x114
[160595.711961] filemap_fault+0x228/0x5f4
[160595.716272] do_read_fault+0xe0/0x1f0
[160595.720487] do_fault+0x40/0x1c8
Tested by injecting random failures into bfq_get_queue, crashes go away
completely.
Fixes: 8ef3fc3a04 ("block, bfq: make shared queues inherit wakers")
Signed-off-by: Khazhismel Kumykov <khazhy@google.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20221108181030.1611703-1-khazhy@google.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When a bio's queue supports PCI P2PDMA, set FOLL_PCI_P2PDMA for
iov_iter_get_pages_flags(). This allows PCI P2PDMA pages to be
passed from userspace and enables the NVMe passthru requests to
use P2PDMA pages.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221021174116.7200-8-logang@deltatee.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When a bio's queue supports PCI P2PDMA, set FOLL_PCI_P2PDMA for
iov_iter_get_pages_flags(). This allows PCI P2PDMA pages to be passed
from userspace and enables the O_DIRECT path in iomap based filesystems
and direct to block devices.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221021174116.7200-7-logang@deltatee.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Consecutive zone device pages should not be merged into the same sgl
or bvec segment with other types of pages or if they belong to different
pgmaps. Otherwise getting the pgmap of a given segment is not possible
without scanning the entire segment. This helper returns true either if
both pages are not zone device pages or both pages are zone device
pages with the same pgmap.
Add a helper to determine if zone device pages are mergeable and use
this helper in page_is_mergeable().
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221021174116.7200-5-logang@deltatee.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In accordance with [1] the DMA-able memory buffers must be
cacheline-aligned otherwise the cache writing-back and invalidation
performed during the mapping may cause the adjacent data being lost. It's
specifically required for the DMA-noncoherent platforms [2]. Seeing the
opal_dev.{cmd,resp} buffers are implicitly used for DMAs in the NVME and
SCSI/SD drivers in framework of the nvme_sec_submit() and sd_sec_submit()
methods respectively they must be cacheline-aligned to prevent the denoted
problem. One of the option to guarantee that is to kmalloc the buffers
[2]. Let's explicitly allocate them then instead of embedding into the
opal_dev structure instance.
Note this fix was inspired by the commit c94b7f9bab ("nvme-hwmon:
kmalloc the NVME SMART log buffer").
[1] Documentation/core-api/dma-api.rst
[2] Documentation/core-api/dma-api-howto.rst
Fixes: 455a7b238c ("block: Add Sed-opal library")
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221107203944.31686-1-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Remove the description of @required_features in elevator_match()
to clear the below warning:
block/elevator.c:103: warning: Excess function parameter 'required_features' description in 'elevator_match'
Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=2734
Fixes: ffb86425ee ("block: don't check for required features in elevator_match")
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Link: https://lore.kernel.org/r/20221107062255.2685-1-yang.lee@linux.alibaba.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'block-6.1-2022-11-05' of git://git.kernel.dk/linux
Pull block fixes from Jens Axboe:
- Fixes for the ublk driver (Ming)
- Fixes for error handling memory leaks (Chen Jun, Chen Zhongjin)
- Explicitly clear the last request in a chain when the plug is
flushed, as it may have already been issued (Al)
* tag 'block-6.1-2022-11-05' of git://git.kernel.dk/linux:
block: blk_add_rq_to_plug(): clear stale 'last' after flush
blk-mq: Fix kmemleak in blk_mq_init_allocated_queue
block: Fix possible memory leak for rq_wb on add_disk failure
ublk_drv: add ublk_queue_cmd() for cleanup
ublk_drv: avoid to touch io_uring cmd in blk_mq io path
ublk_drv: comment on ublk_driver entry of Kconfig
ublk_drv: return flag of UBLK_F_URING_CMD_COMP_IN_TASK in case of module
Drivers that have shared tagsets may need to quiesce potentially a lot
of request queues that all share a single tagset (e.g. nvme). Add an
interface to quiesce all the queues on a given tagset. This interface is
useful because it can speedup the quiesce by doing it in parallel.
Because some queues should not need to be quiesced (e.g. the nvme
connect_q) when quiescing the tagset, introduce a
QUEUE_FLAG_SKIP_TAGSET_QUIESCE flag to allow this new interface to
ski quiescing a particular queue.
Signed-off-by: Chao Leng <lengchao@huawei.com>
[hch: simplify for the per-tag_set srcu_struct]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Chao Leng <lengchao@huawei.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221101150050.3510-14-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Nothing in blk_mq_wait_quiesce_done needs the request_queue now, so just
pass the tagset, and move the non-mq check into the only caller that
needs it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chao Leng <lengchao@huawei.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221101150050.3510-13-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
All I/O submissions have fairly similar latencies, and a tagset-wide
quiesce is a fairly common operation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Chao Leng <lengchao@huawei.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221101150050.3510-12-hch@lst.de
[axboe: fix whitespace]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
For submit_bio based queues there is no (S)RCU critical section during
I/O submission and thus nothing to wait for in blk_mq_wait_quiesce_done,
so skip doing any synchronization. No non-mq driver should be calling
this, but for now we have core callers that unconditionally call into it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221101150050.3510-11-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
nvme and xen-blkfront are already doing this to stop buffered writes from
creating dirty pages that can't be written out later. Move it to the
common code.
This also removes the comment about the ordering from nvme, as bd_mutex
not only is gone entirely, but also hasn't been used for locking updates
to the disk size long before that, and thus the ordering requirement
documented there doesn't apply any more.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Chao Leng <lengchao@huawei.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20221101150050.3510-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Prevent unnecessary format conversion for bfqg->bfqd in multiple
places.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Paolo Valente <paolo.valente@unimore.it>
Link: https://lore.kernel.org/r/20221102022542.3621219-6-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Such code are not even compiled since they are inside marco "#if 0".
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Paolo Valente <paolo.valente@unimore.it>
Link: https://lore.kernel.org/r/20221102022542.3621219-5-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Just make the code a litter cleaner by removing the unnecessary
variable 'sd'.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Paolo Valente <paolo.valente@unimore.it>
Link: https://lore.kernel.org/r/20221102022542.3621219-4-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Current code is a bit ugly and hard to read.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Paolo Valente <paolo.valente@unimore.it>
Link: https://lore.kernel.org/r/20221102022542.3621219-3-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
After the patch "block, bfq: cleanup bfq_weights_tree add/remove apis"),
the local variable 'bfqd' is not used anymore, thus remove it.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20221102022542.3621219-2-yukuai1@huaweicloud.com
Fixes: afdba14612 ("block, bfq: cleanup bfq_weights_tree add/remove apis")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We only need a max queue depth for every iolatency to limit the inflight io
number. Replace struct rq_depth with unsigned int to simplfy "struct
iolatency_grp" and save memory.
Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Link: https://lore.kernel.org/r/20221018111240.22612-4-shikemeng@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Default queue depth of iolatency_grp is unlimited, so we scale down
quickly(once by half) in scale_cookie_change. Remove the "subtract
1/16th" part which is not the truth and add the actual way we
scale down.
Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Link: https://lore.kernel.org/r/20221018111240.22612-3-shikemeng@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Function blkcg_iolatency_throttle will make sure blkg->parent is not
NULL before calls check_scale_change. And function check_scale_change
is only called in blkcg_iolatency_throttle.
Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Link: https://lore.kernel.org/r/20221018111240.22612-2-shikemeng@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Split an elevator_disable helper from elevator_switch for the case where
we want to switch to no scheduler at all. This includes removing the
pointless elevator_switch_mq helper and removing the switch to no
schedule logic from blk_mq_init_sched.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221030100714.876891-8-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Checking for the required features in the callers simplifies the code
quite a bit, so do that.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221030100714.876891-7-hch@lst.de
[axboe: adjust for dropping patch 1, use __elevator_find()]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Use eq for the elevator_queue as done elsewhere. This frees e to be used
for the loop iterator instead of the odd __ prefix. In addition rename
elv to cur to make it more clear it is the currently selected elevator.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221030100714.876891-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If the tag_set has BLK_MQ_F_NO_SCHED flag set we will never show any
scheduler, so exit early.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221030100714.876891-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Do the request_module and repeated lookup in the only caller that cares,
pick a saner name that explains where are actually doing a lookup and
use a sane calling conventions that passes the queue first.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221030100714.876891-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
It's the same with bfq_weights_tree_remove() now.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Paolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20220916071942.214222-7-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The 'bfq_data' and 'rb_root_cached' can both be accessed through
'bfq_queue', thus only pass 'bfq_queue' as parameter.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Paolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20220916071942.214222-6-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Now that root group is counted into 'num_groups_with_pending_reqs',
'num_groups_with_pending_reqs > 0' is always true in
bfq_asymmetric_scenario(). Thus change the condition to '> 1'.
On the other hand, this change can enable concurrent sync io if only
one group is activated.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Paolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20220916071942.214222-5-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently, bfq can't handle sync io concurrently as long as they
are not issued from root group. This is because
'bfqd->num_groups_with_pending_reqs > 0' is always true in
bfq_asymmetric_scenario().
The way that bfqg is counted into 'num_groups_with_pending_reqs':
Before this patch:
1) root group will never be counted.
2) Count if bfqg or it's child bfqgs have pending requests.
3) Don't count if bfqg and it's child bfqgs complete all the requests.
After this patch:
1) root group is counted.
2) Count if bfqg have pending requests.
3) Don't count if bfqg complete all the requests.
With this change, the occasion that only one group is activated can be
detected, and next patch will support concurrent sync io in the
occasion.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Paolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20220916071942.214222-4-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Prepare to refactor the counting of 'num_groups_with_pending_reqs'.
Add a counter in bfq_group, update it while tracking if bfqq have pending
requests and when bfq_bfqq_move() is called.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Paolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20220916071942.214222-3-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If entity belongs to bfqq, then entity->in_groups_with_pending_reqs
is not used currently. This patch use it to track if bfqq has pending
requests through callers of weights_tree insertion and removal.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Paolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20220916071942.214222-2-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk_mq_flush_plug_list() empties ->mq_list and request we'd peeked there
before that call is gone; in any case, we are not dealing with a mix
of requests for different queues now - there's no requests left in the
plug.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There is a kmemleak caused by modprobe null_blk.ko
unreferenced object 0xffff8881acb1f000 (size 1024):
comm "modprobe", pid 836, jiffies 4294971190 (age 27.068s)
hex dump (first 32 bytes):
00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00 .....N..........
ff ff ff ff ff ff ff ff 00 53 99 9e ff ff ff ff .........S......
backtrace:
[<000000004a10c249>] kmalloc_node_trace+0x22/0x60
[<00000000648f7950>] blk_mq_alloc_and_init_hctx+0x289/0x350
[<00000000af06de0e>] blk_mq_realloc_hw_ctxs+0x2fe/0x3d0
[<00000000e00c1872>] blk_mq_init_allocated_queue+0x48c/0x1440
[<00000000d16b4e68>] __blk_mq_alloc_disk+0xc8/0x1c0
[<00000000d10c98c3>] 0xffffffffc450d69d
[<00000000b9299f48>] 0xffffffffc4538392
[<0000000061c39ed6>] do_one_initcall+0xd0/0x4f0
[<00000000b389383b>] do_init_module+0x1a4/0x680
[<0000000087cf3542>] load_module+0x6249/0x7110
[<00000000beba61b8>] __do_sys_finit_module+0x140/0x200
[<00000000fdcfff51>] do_syscall_64+0x35/0x80
[<000000003c0f1f71>] entry_SYSCALL_64_after_hwframe+0x46/0xb0
That is because q->ma_ops is set to NULL before blk_release_queue is
called.
blk_mq_init_queue_data
blk_mq_init_allocated_queue
blk_mq_realloc_hw_ctxs
for (i = 0; i < set->nr_hw_queues; i++) {
old_hctx = xa_load(&q->hctx_table, i);
if (!blk_mq_alloc_and_init_hctx(.., i, ..)) [1]
if (!old_hctx)
break;
xa_for_each_start(&q->hctx_table, j, hctx, j)
blk_mq_exit_hctx(q, set, hctx, j); [2]
if (!q->nr_hw_queues) [3]
goto err_hctxs;
err_exit:
q->mq_ops = NULL; [4]
blk_put_queue
blk_release_queue
if (queue_is_mq(q)) [5]
blk_mq_release(q);
[1]: blk_mq_alloc_and_init_hctx failed at i != 0.
[2]: The hctxs allocated by [1] are moved to q->unused_hctx_list and
will be cleaned up in blk_mq_release.
[3]: q->nr_hw_queues is 0.
[4]: Set q->mq_ops to NULL.
[5]: queue_is_mq returns false due to [4]. And blk_mq_release
will not be called. The hctxs in q->unused_hctx_list are leaked.
To fix it, call blk_release_queue in exception path.
Fixes: 2f8f1336a4 ("blk-mq: always free hctx after request queue is freed")
Signed-off-by: Yuan Can <yuancan@huawei.com>
Signed-off-by: Chen Jun <chenjun102@huawei.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20221031031242.94107-1-chenjun102@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The calling relationship in blk_mq_destroy_queue() is as follows:
blk_mq_destroy_queue()
...
-> blk_queue_start_drain()
-> blk_freeze_queue_start() <- called
...
-> blk_freeze_queue()
-> blk_freeze_queue_start() <- called again
-> blk_mq_freeze_queue_wait()
...
So there is a redundant call to blk_freeze_queue_start().
Replace blk_freeze_queue() with blk_mq_freeze_queue_wait() to avoid the
redundant call.
Signed-off-by: Jinlong Chen <nickyc975@zju.edu.cn>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221030083212.1251255-1-nickyc975@zju.edu.cn
Signed-off-by: Jens Axboe <axboe@kernel.dk>
kmemleak reported memory leaks in device_add_disk():
kmemleak: 3 new suspected memory leaks
unreferenced object 0xffff88800f420800 (size 512):
comm "modprobe", pid 4275, jiffies 4295639067 (age 223.512s)
hex dump (first 32 bytes):
04 00 00 00 08 00 00 00 01 00 00 00 00 00 00 00 ................
00 e1 f5 05 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<00000000d3662699>] kmalloc_trace+0x26/0x60
[<00000000edc7aadc>] wbt_init+0x50/0x6f0
[<0000000069601d16>] wbt_enable_default+0x157/0x1c0
[<0000000028fc393f>] blk_register_queue+0x2a4/0x420
[<000000007345a042>] device_add_disk+0x6fd/0xe40
[<0000000060e6aab0>] nbd_dev_add+0x828/0xbf0 [nbd]
...
It is because the memory allocated in wbt_enable_default() is not
released in device_add_disk() error path.
Normally, these memory are freed in:
del_gendisk()
rq_qos_exit()
rqos->ops->exit(rqos);
wbt_exit()
So rq_qos_exit() is called to free the rq_wb memory for wbt_init().
However in the error path of device_add_disk(), only
blk_unregister_queue() is called and make rq_wb memory leaked.
Add rq_qos_exit() to the error path to fix it.
Fixes: 83cbce9574 ("block: add error handling for device_add_disk / add_disk")
Signed-off-by: Chen Zhongjin <chenzhongjin@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221029071355.35462-1-chenzhongjin@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The only caller that needs queue_is_mq check is del_gendisk, so move the
check into it.
Signed-off-by: Jinlong Chen <nickyc975@zju.edu.cn>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221030094730.1275463-1-nickyc975@zju.edu.cn
Signed-off-by: Jens Axboe <axboe@kernel.dk>
David Jeffery found one double ->queue_rq() issue, so far it can
be triggered in VM use case because of long vmexit latency or preempt
latency of vCPU pthread or long page fault in vCPU pthread, then block
IO req could be timed out before queuing the request to hardware but after
calling blk_mq_start_request() during ->queue_rq(), then timeout handler
may handle it by requeue, then double ->queue_rq() is caused, and kernel
panic.
So far, it is driver's responsibility to cover the race between timeout
and completion, so it seems supposed to be solved in driver in theory,
given driver has enough knowledge.
But it is really one common problem, lots of driver could have similar
issue, and could be hard to fix all affected drivers, even it isn't easy
for driver to handle the race. So David suggests this patch by draining
in-progress ->queue_rq() for solving this issue.
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Keith Busch <kbusch@kernel.org>
Cc: virtualization@lists.linux-foundation.org
Cc: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: David Jeffery <djeffery@redhat.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20221026051957.358818-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'block-6.1-2022-10-28' of git://git.kernel.dk/linux
Pull block fixes from Jens Axboe:
- NVMe pull request via Christoph:
- make the multipath dma alignment match the non-multipath one
(Keith Busch)
- fix a bogus use of sg_init_marker() (Nam Cao)
- fix circulr locking in nvme-tcp (Sagi Grimberg)
- Initialization fix for requests allocated via the special hw queue
allocator (John)
- Fix for a regression added in this release with the batched
completions of end_io backed requests (Ming)
- Error handling leak fix for rbd (Yang)
- Error handling leak fix for add_disk() failure (Yu)
* tag 'block-6.1-2022-10-28' of git://git.kernel.dk/linux:
blk-mq: Properly init requests from blk_mq_alloc_request_hctx()
blk-mq: don't add non-pt request with ->end_io to batch
rbd: fix possible memory leak in rbd_sysfs_init()
nvme-multipath: set queue dma alignment to 3
nvme-tcp: fix possible circular locking when deleting a controller under memory pressure
nvme-tcp: replace sg_init_marker() with sg_init_table()
block: fix memory leak for elevator on add_disk failure
Function blk_mq_alloc_request_hctx() is missing zeroing/init of rq->bio,
biotail, __sector, and __data_len members, which blk_mq_alloc_request()
has, so duplicate what we do in blk_mq_alloc_request().
Fixes: 1f5bd336b9 ("blk-mq: add blk_mq_alloc_request_hctx")
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/1666780513-121650-1-git-send-email-john.garry@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Document which functions do not modify the queue limits.
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Keith Busch <kbusch@kernel.org>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20221025191755.1711437-3-bvanassche@acm.org
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The fact that blk_mq_destroy_queue also drops a queue reference leads
to various places having to grab an extra reference. Move the call to
blk_put_queue into the callers to allow removing the extra references.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20221018135720.670094-2-hch@lst.de
[axboe: fix fabrics_q vs admin_q conflict in nvme core.c]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The current reference management logic of io scheduler modules contains
refcnt problems. For example, blk_mq_init_sched may fail before or after
the calling of e->ops.init_sched. If it fails before the calling, it does
nothing to the reference to the io scheduler module. But if it fails after
the calling, it releases the reference by calling kobject_put(&eq->kobj).
As the callers of blk_mq_init_sched can't know exactly where the failure
happens, they can't handle the reference to the io scheduler module
properly: releasing the reference on failure results in double-release if
blk_mq_init_sched has released it, and not releasing the reference results
in ghost reference if blk_mq_init_sched did not release it either.
The same problem also exists in io schedulers' init_sched implementations.
We can address the problem by adding releasing statements to the error
handling procedures of blk_mq_init_sched and init_sched implementations.
But that is counterintuitive and requires modifications to existing io
schedulers.
Instead, We make elevator_alloc get the io scheduler module references
that will be released by elevator_release. And then, we match each
elevator_get with an elevator_put. Therefore, each reference to an io
scheduler module explicitly has its own getter and releaser, and we no
longer need to worry about the refcnt problems.
The bugs and the patch can be validated with tools here:
https://github.com/nickyc975/linux_elv_refcnt_bug.git
[hch: split out a few bits into separate patches, use a non-try
module_get in elevator_alloc]
Signed-off-by: Jinlong Chen <nickyc975@zju.edu.cn>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221020064819.1469928-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
No need to find the actual elevator_type struct for this comparism,
the name is all that is needed.
Signed-off-by: Jinlong Chen <nickyc975@zju.edu.cn>
[hch: split from a larger patch]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221020064819.1469928-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The stripped name should also be used for the none check. To do so
strip it in the caller and pass in the sanitized name. Drop the pointless
__ prefix in the function name while we're at it.
Based on a patch from Jinlong Chen <nickyc975@zju.edu.cn>.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221020064819.1469928-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Make sure we have helpers for all relevant module refcount operations on
the elevator_type in elevator.h, and use them. Move the call to the get
helper in blk_mq_elv_switch_none a bit so that it is obvious with a less
verbose comment.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221020064819.1469928-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Commit b5dc5d4d1f ("block,bfq: Disable writeback throttling") tries to
disable wbt for bfq, it's done by calling wbt_disable_default() in
bfq_init_queue(). However, wbt is still enabled if default elevator is
bfq:
device_add_disk
elevator_init_mq
bfq_init_queue
wbt_disable_default -> done nothing
blk_register_queue
wbt_enable_default -> wbt is enabled
Fix the problem by adding a new flag ELEVATOR_FLAG_DISBALE_WBT, bfq
will set the flag in bfq_init_queue, and following wbt_enable_default()
won't enable wbt while the flag is set.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221019121518.3865235-7-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There are only one flag to indicate that elevator is registered currently,
prepare to add a flag to disable wbt if default elevator is bfq.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221019121518.3865235-6-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently, if wbt is initialized and then disabled by
wbt_disable_default(), sysfs will still show valid wbt_lat_usec, which
will confuse users that wbt is still enabled.
This patch shows wbt_lat_usec as zero if it's disabled.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reported-and-tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221019121518.3865235-5-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently, if user disable wbt through sysfs, 'enable_state' will be
'WBT_STATE_ON_MANUAL', which will be confusing. Add a new state
'WBT_STATE_OFF_MANUAL' to cover that case.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221019121518.3865235-4-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
"elevator_queue *e" is already declared and initialized in the beginning
of elv_unregister_queue().
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20221019121518.3865235-2-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
'ioc->params' is updated in ioc_refresh_params(), which is proteced by
'ioc->lock', however, ioc_timer_fn() read params outside the lock.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20221012094035.390056-5-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This won't cause any severe problem currently, however, this doesn't
seems appropriate:
1) 'ioc->params' is read from multiple places without holding
'ioc->lock', unexpected value might be read if writing it concurrently.
2) If configuration is changed while io is throttling, the functionality
might be affected. For example, if module params is updated and cost
becomes smaller, waiting for timer that is caculated under old
configuration is not appropriate.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20221012094035.390056-4-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
ioc_qos_write() and ioc_cost_model_write() are the same:
1) hold lock to read 'ioc->params' to local variable;
2) update params to local variable without lock;
3) hold lock to write local variable to 'ioc->params';
In theroy, if user updates params concurrenty, the params might be lost:
t1: update params a t2: update params b
spin_lock_irq(&ioc->lock);
memcpy(qos, ioc->params.qos, sizeof(qos))
spin_unlock_irq(&ioc->lock);
qos[a] = xxx;
spin_lock_irq(&ioc->lock);
memcpy(qos, ioc->params.qos, sizeof(qos))
spin_unlock_irq(&ioc->lock);
qos[b] = xxx;
spin_lock_irq(&ioc->lock);
memcpy(ioc->params.qos, qos, sizeof(qos));
ioc_refresh_params(ioc, true);
spin_unlock_irq(&ioc->lock);
spin_lock_irq(&ioc->lock);
// updates of a will be lost
memcpy(ioc->params.qos, qos, sizeof(qos));
ioc_refresh_params(ioc, true);
spin_unlock_irq(&ioc->lock);
Althrough this is not common case, the problem can by fixed easily by
holding the lock through the read, update, write process.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20221012094035.390056-3-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Ming Lei