Now we only verify the outmost freeze & unfreeze in current context in case
that !q->mq_freeze_depth, so it is reliable to save queue lying state when
we want to lock the freeze queue since the state is one per-task variable
now.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20241127135133.3952153-5-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move a statement that occurs in both branches of an if-statement in front
of the if-statement. Fix a typo in a source code comment. No functionality
has been changed.
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20241212212941.1268662-3-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Registering and unregistering cpuhp callback requires global cpu hotplug lock,
which is used everywhere. Meantime q->sysfs_lock is used in block layer
almost everywhere.
It is easy to trigger lockdep warning[1] by connecting the two locks.
Fix the warning by moving blk-mq's cpuhp callback registering out of
q->sysfs_lock. Add one dedicated global lock for covering registering &
unregistering hctx's cpuhp, and it is safe to do so because hctx is
guaranteed to be live if our request_queue is live.
[1] https://lore.kernel.org/lkml/Z04pz3AlvI4o0Mr8@agluck-desk3/
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Peter Newman <peternewman@google.com>
Cc: Babu Moger <babu.moger@amd.com>
Reported-by: Luck Tony <tony.luck@intel.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Tested-by: Tony Luck <tony.luck@intel.com>
Link: https://lore.kernel.org/r/20241206111611.978870-3-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We need to retrieve 'hctx' from xarray table in the cpuhp callback, so the
callback should be registered after this 'hctx' is added to xarray table.
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Peter Newman <peternewman@google.com>
Cc: Babu Moger <babu.moger@amd.com>
Cc: Luck Tony <tony.luck@intel.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Tested-by: Tony Luck <tony.luck@intel.com>
Link: https://lore.kernel.org/r/20241206111611.978870-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Fix an issue detected by the `smatch` tool:
block/blk-mq.c:3314 blk_rq_prep_clone() error: uninitialized
symbol 'bio'.
This patch refactors `blk_rq_prep_clone()` to improve code
readability and ensure safety by addressing potential misuse of
the `bio` variable:
- Move the bio_put(bio); call to the bio_ctr error handling block,
which is the only place where it can be triggered.
- Move the bio variable into the __rq_for_each_bio loop scope.
This change removes the need to set bio to NULL at the loop's
end.
discussion on why bio remains uninitialized:
https://lore.kernel.org/lkml/20241004141037.43277-1-surajsonawane0215@gmail.com
Summary of above discussion:
- I pointed out that `bio` can remain uninitialized if the
allocation with `bio_alloc_clone` fails.
- Keith Busch explained that `bio` is initialized to `NULL` when
`bio_alloc_clone()` fails, preventing uninitialized usage.
- John Garry questioned whether `rq_src->bio` being `NULL` could
leave `bio` uninitialized. Keith clarified that in such cases,
`bio` is not referenced, so it does not need initialization.
- Christoph Hellwig recommended code improvements:
- move the bio_put to the bio_ctr error handling, which is the only
case where it can happen
- move the bio variable into the __rq_for_each_bio scope, which
also removed the need to zero it at the end of the loop
These changes enhance code clarity, address static analysis tool
warnings, and make the function more maintainable.
thread of previous version patch discussion:
https://lore.kernel.org/lkml/20241004100842.9052-1-surajsonawane0215@gmail.com
Signed-off-by: Suraj Sonawane <surajsonawane0215@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20241119164412.37609-1-surajsonawane0215@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add requests to the tail of the list instead of the front so that they
are queued up in submission order.
Remove the re-reordering in blk_mq_dispatch_plug_list, virtio_queue_rqs
and nvme_queue_rqs now that the list is ordered as expected.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20241113152050.157179-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Replace the semi-open coded request list helpers with a proper rq_list
type that mirrors the bio_list and has head and tail pointers. Besides
better type safety this actually allows to insert at the tail of the
list, which will be useful soon.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20241113152050.157179-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The request ioprio is only initialized from the first attached bio,
so requests without a bio already never set it. Directly use the
bio field instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20241112170050.1612998-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The write_hint is only used for read/write requests, which must have a
bio attached to them. Just use the bio field instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20241112170050.1612998-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
commit f1be1788a3 ("block: model freeze & enter queue as lock for
supporting lockdep") tries to apply lockdep for verifying freeze &
unfreeze. However, the verification is only done the outmost freeze and
unfreeze. This way is actually not correct because q->mq_freeze_depth
still may drop to zero on other task instead of the freeze owner task.
Fix this issue by always verifying the last unfreeze lock on the owner
task context, and make sure both the outmost freeze & unfreeze are
verified in the current task.
Fixes: f1be1788a3 ("block: model freeze & enter queue as lock for supporting lockdep")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20241031133723.303835-4-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
No one use blk_freeze_queue(), so remove it and the obsolete comment.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20241031133723.303835-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Recently we got several deadlock report[1][2][3] caused by
blk_mq_freeze_queue and blk_enter_queue().
Turns out the two are just like acquiring read/write lock, so model them
as read/write lock for supporting lockdep:
1) model q->q_usage_counter as two locks(io and queue lock)
- queue lock covers sync with blk_enter_queue()
- io lock covers sync with bio_enter_queue()
2) make the lockdep class/key as per-queue:
- different subsystem has very different lock use pattern, shared lock
class causes false positive easily
- freeze_queue degrades to no lock in case that disk state becomes DEAD
because bio_enter_queue() won't be blocked any more
- freeze_queue degrades to no lock in case that request queue becomes dying
because blk_enter_queue() won't be blocked any more
3) model blk_mq_freeze_queue() as acquire_exclusive & try_lock
- it is exclusive lock, so dependency with blk_enter_queue() is covered
- it is trylock because blk_mq_freeze_queue() are allowed to run
concurrently
4) model blk_enter_queue() & bio_enter_queue() as acquire_read()
- nested blk_enter_queue() are allowed
- dependency with blk_mq_freeze_queue() is covered
- blk_queue_exit() is often called from other contexts(such as irq), and
it can't be annotated as lock_release(), so simply do it in
blk_enter_queue(), this way still covered cases as many as possible
With lockdep support, such kind of reports may be reported asap and
needn't wait until the real deadlock is triggered.
For example, lockdep report can be triggered in the report[3] with this
patch applied.
[1] occasional block layer hang when setting 'echo noop > /sys/block/sda/queue/scheduler'
https://bugzilla.kernel.org/show_bug.cgi?id=219166
[2] del_gendisk() vs blk_queue_enter() race condition
https://lore.kernel.org/linux-block/20241003085610.GK11458@google.com/
[3] queue_freeze & queue_enter deadlock in scsi
https://lore.kernel.org/linux-block/ZxG38G9BuFdBpBHZ@fedora/T/#u
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20241025003722.3630252-4-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add non_owner variant of start_freeze/unfreeze queue APIs, so that the
caller knows that what they are doing, and we can skip lockdep support
for non_owner variant in per-call level.
Prepare for supporting lockdep for freezing/unfreezing queue.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20241025003722.3630252-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Commit a6088845c2 ("block: kyber: make kyber more friendly with merging")
removed the only blk_mq_flush_busy_ctxs() call from outside the block layer
core. Hence unexport blk_mq_flush_busy_ctxs().
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20241023202850.3469279-1-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Make sure that the tag_list_lock mutex is not held any longer than
necessary. This change reduces latency if e.g. blk_mq_quiesce_tagset()
is called concurrently from more than one thread. This function is used
by the NVMe core and also by the UFS driver.
Reported-by: Peter Wang <peter.wang@mediatek.com>
Cc: Chao Leng <lengchao@huawei.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 414dd48e88 ("blk-mq: add tagset quiesce interface")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20241022181617.2716173-1-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Supposing first scenario with a virtio_blk driver.
CPU0 CPU1
blk_mq_try_issue_directly()
__blk_mq_issue_directly()
q->mq_ops->queue_rq()
virtio_queue_rq()
blk_mq_stop_hw_queue()
virtblk_done()
blk_mq_request_bypass_insert() 1) store
blk_mq_start_stopped_hw_queue()
clear_bit(BLK_MQ_S_STOPPED) 3) store
blk_mq_run_hw_queue()
if (!blk_mq_hctx_has_pending()) 4) load
return
blk_mq_sched_dispatch_requests()
blk_mq_run_hw_queue()
if (!blk_mq_hctx_has_pending())
return
blk_mq_sched_dispatch_requests()
if (blk_mq_hctx_stopped()) 2) load
return
__blk_mq_sched_dispatch_requests()
Supposing another scenario.
CPU0 CPU1
blk_mq_requeue_work()
blk_mq_insert_request() 1) store
virtblk_done()
blk_mq_start_stopped_hw_queue()
blk_mq_run_hw_queues() clear_bit(BLK_MQ_S_STOPPED) 3) store
blk_mq_run_hw_queue()
if (!blk_mq_hctx_has_pending()) 4) load
return
blk_mq_sched_dispatch_requests()
if (blk_mq_hctx_stopped()) 2) load
continue
blk_mq_run_hw_queue()
Both scenarios are similar, the full memory barrier should be inserted
between 1) and 2), as well as between 3) and 4) to make sure that either
CPU0 sees BLK_MQ_S_STOPPED is cleared or CPU1 sees dispatch list.
Otherwise, either CPU will not rerun the hardware queue causing
starvation of the request.
The easy way to fix it is to add the essential full memory barrier into
helper of blk_mq_hctx_stopped(). In order to not affect the fast path
(hardware queue is not stopped most of the time), we only insert the
barrier into the slow path. Actually, only slow path needs to care about
missing of dispatching the request to the low-level device driver.
Fixes: 320ae51fee ("blk-mq: new multi-queue block IO queueing mechanism")
Cc: stable@vger.kernel.org
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20241014092934.53630-4-songmuchun@bytedance.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Supposing the following scenario.
CPU0 CPU1
blk_mq_insert_request() 1) store
blk_mq_unquiesce_queue()
blk_queue_flag_clear() 3) store
blk_mq_run_hw_queues()
blk_mq_run_hw_queue()
if (!blk_mq_hctx_has_pending()) 4) load
return
blk_mq_run_hw_queue()
if (blk_queue_quiesced()) 2) load
return
blk_mq_sched_dispatch_requests()
The full memory barrier should be inserted between 1) and 2), as well as
between 3) and 4) to make sure that either CPU0 sees QUEUE_FLAG_QUIESCED
is cleared or CPU1 sees dispatch list or setting of bitmap of software
queue. Otherwise, either CPU will not rerun the hardware queue causing
starvation.
So the first solution is to 1) add a pair of memory barrier to fix the
problem, another solution is to 2) use hctx->queue->queue_lock to
synchronize QUEUE_FLAG_QUIESCED. Here, we chose 2) to fix it since
memory barrier is not easy to be maintained.
Fixes: f4560ffe8c ("blk-mq: use QUEUE_FLAG_QUIESCED to quiesce queue")
Cc: stable@vger.kernel.org
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20241014092934.53630-3-songmuchun@bytedance.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Supposing the following scenario with a virtio_blk driver.
CPU0 CPU1 CPU2
blk_mq_try_issue_directly()
__blk_mq_issue_directly()
q->mq_ops->queue_rq()
virtio_queue_rq()
blk_mq_stop_hw_queue()
virtblk_done()
blk_mq_try_issue_directly()
if (blk_mq_hctx_stopped())
blk_mq_request_bypass_insert() blk_mq_run_hw_queue()
blk_mq_run_hw_queue() blk_mq_run_hw_queue()
blk_mq_insert_request()
return
After CPU0 has marked the queue as stopped, CPU1 will see the queue is
stopped. But before CPU1 puts the request on the dispatch list, CPU2
receives the interrupt of completion of request, so it will run the
hardware queue and marks the queue as non-stopped. Meanwhile, CPU1 also
runs the same hardware queue. After both CPU1 and CPU2 complete
blk_mq_run_hw_queue(), CPU1 just puts the request to the same hardware
queue and returns. It misses dispatching a request. Fix it by running
the hardware queue explicitly. And blk_mq_request_issue_directly()
should handle a similar situation. Fix it as well.
Fixes: d964f04a8f ("blk-mq: fix direct issue")
Cc: stable@vger.kernel.org
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20241014092934.53630-2-songmuchun@bytedance.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Applications using the passthrough interfaces for IO want to continue
seeing the disk stats. These requests had been fenced off from this
block layer feature. While the block layer doesn't necessarily know what
a passthrough command does, we do know the data size and direction,
which is enough to account for the command's stats.
Since tracking these has the potential to produce unexpected results,
the passthrough stats are locked behind a new queue flag that needs to
be enabled with the /sys/block/<dev>/queue/iostats_passthrough
attribute.
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20241007153236.2818562-1-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
It's known needed at that point, and it's cleaner to just assign it
there rather than rely on it being reliably set before hitting the
IO accounting. Hence, move it out of blk_mq_rq_time_init(), which is
now only doing the allocation side timing.
While at it, get rid of the '0' time passing to blk_mq_rq_time_init(),
just pass in blk_time_get_ns() for the two cases where 0 is being
explicitly passed in. The rest pass in the previously cached allocation
time.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
A previous commit moved RQF_IO_STAT into blk_account_io_done(), where
it's being set rather than at allocation time. Unfortunately we do check
for that flag in blk_mq_rq_time_init(), and hence setting the
start_time_ns wasn't being done. This lead to unwieldy inflight IO counts
and times, as IO completion accounting would a 0 value rather than the
issue time for it's subtraction math.
Fix this by switching the blk_mq_rq_time_init() check to use the queue
state rather than the request state.
Fixes: b8f762400a ("block: move iostat check into blk_acount_io_start()")
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202410062110.512391df-oliver.sang@intel.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
It's now just checking whether or not RQF_IO_STAT is set, so let's get
rid of it and just open-code the specific flag that is being checked.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If RQF_IO_STAT is set, then accounting is enabled. There's no need to
further gate this on req->part being set or not, RQF_IO_STAT should
never be set if accounting is not being done for this request.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Rather than have blk_do_io_stat() check for both RQF_IO_STAT and whether
the request is a passthrough requests every time, move both of those
checks into blk_account_io_start(). Then blk_do_io_stat() can be reduced
to just checking for RQF_IO_STAT.
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Anuj Gupta <anuj20.g@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Commit 7b815817aa ("blk-mq: add helper for checking if one CPU is mapped to specified hctx")
needs to check queue mapping via tag set in hctx's cpuhp handler.
However, q->tag_set may not be setup yet when the cpuhp handler is
enabled, then kernel oops is triggered.
Fix the issue by setup queue tag_set before initializing hctx.
Cc: stable@vger.kernel.org
Reported-and-tested-by: Rick Koch <mr.rickkoch@gmail.com>
Closes: https://lore.kernel.org/linux-block/CANa58eeNDozLaBHKPLxSAhEy__FPfJT_F71W=sEQw49UCrC9PQ@mail.gmail.com
Fixes: 7b815817aa ("blk-mq: add helper for checking if one CPU is mapped to specified hctx")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Link: https://lore.kernel.org/r/20241014005115.2699642-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'for-6.12/block-20240925' of git://git.kernel.dk/linux
Pull more block updates from Jens Axboe:
- Improve blk-integrity segment counting and merging (Keith)
- NVMe pull request via Keith:
- Multipath fixes (Hannes)
- Sysfs attribute list NULL terminate fix (Shin'ichiro)
- Remove problematic read-back (Keith)
- Fix for a regression with the IO scheduler switching freezing from
6.11 (Damien)
- Use a raw spinlock for sbitmap, as it may get called from preempt
disabled context (Ming)
- Cleanup for bd_claiming waiting, using var_waitqueue() rather than
the bit waitqueues, as that more accurately describes that it does
(Neil)
- Various cleanups (Kanchan, Qiu-ji, David)
* tag 'for-6.12/block-20240925' of git://git.kernel.dk/linux:
nvme: remove CC register read-back during enabling
nvme: null terminate nvme_tls_attrs
nvme-multipath: avoid hang on inaccessible namespaces
nvme-multipath: system fails to create generic nvme device
lib/sbitmap: define swap_lock as raw_spinlock_t
block: Remove unused blk_limits_io_{min,opt}
drbd: Fix atomicity violation in drbd_uuid_set_bm()
block: Fix elv_iosched_local_module handling of "none" scheduler
block: remove bogus union
block: change wait on bd_claiming to use a var_waitqueue
blk-integrity: improved sg segment mapping
block: unexport blk_rq_count_integrity_sg
nvme-rdma: use request to get integrity segments
scsi: use request to get integrity segments
block: provide a request helper for user integrity segments
blk-integrity: consider entire bio list for merging
blk-integrity: properly account for segments
blk-mq: set the nr_integrity_segments from bio
blk-mq: unconditional nr_integrity_segments
- Core:
- Remove a global lock in the affinity setting code
The lock protects a cpumask for intermediate results and the lock
causes a bottleneck on simultaneous start of multiple virtual
machines. Replace the lock and the static cpumask with a per CPU
cpumask which is nicely serialized by raw spinlock held when
executing this code.
- Provide support for giving a suffix to interrupt domain names.
That's required to support devices with subfunctions so that the
domain names are distinct even if they originate from the same
device node.
- The usual set of cleanups and enhancements all over the place
- Drivers:
- Support for longarch AVEC interrupt chip
- Refurbishment of the Armada driver so it can be extended for new
variants.
- The usual set of cleanups and enhancements all over the place
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Merge tag 'irq-core-2024-09-16' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner:
"Core:
- Remove a global lock in the affinity setting code
The lock protects a cpumask for intermediate results and the lock
causes a bottleneck on simultaneous start of multiple virtual
machines. Replace the lock and the static cpumask with a per CPU
cpumask which is nicely serialized by raw spinlock held when
executing this code.
- Provide support for giving a suffix to interrupt domain names.
That's required to support devices with subfunctions so that the
domain names are distinct even if they originate from the same
device node.
- The usual set of cleanups and enhancements all over the place
Drivers:
- Support for longarch AVEC interrupt chip
- Refurbishment of the Armada driver so it can be extended for new
variants.
- The usual set of cleanups and enhancements all over the place"
* tag 'irq-core-2024-09-16' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (73 commits)
genirq: Use cpumask_intersects()
genirq/cpuhotplug: Use cpumask_intersects()
irqchip/apple-aic: Only access system registers on SoCs which provide them
irqchip/apple-aic: Add a new "Global fast IPIs only" feature level
irqchip/apple-aic: Skip unnecessary enabling of use_fast_ipi
dt-bindings: apple,aic: Document A7-A11 compatibles
irqdomain: Use IS_ERR_OR_NULL() in irq_domain_trim_hierarchy()
genirq/msi: Use kmemdup_array() instead of kmemdup()
genirq/proc: Change the return value for set affinity permission error
genirq/proc: Use irq_move_pending() in show_irq_affinity()
genirq/proc: Correctly set file permissions for affinity control files
genirq: Get rid of global lock in irq_do_set_affinity()
genirq: Fix typo in struct comment
irqchip/loongarch-avec: Add AVEC irqchip support
irqchip/loongson-pch-msi: Prepare get_pch_msi_handle() for AVECINTC
irqchip/loongson-eiointc: Rename CPUHP_AP_IRQ_LOONGARCH_STARTING
LoongArch: Architectural preparation for AVEC irqchip
LoongArch: Move irqchip function prototypes to irq-loongson.h
irqchip/loongson-pch-msi: Switch to MSI parent domains
softirq: Remove unused 'action' parameter from action callback
...
This value is used for merging considerations, so it needs to be
accurate.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20240913182854.2445457-3-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Always defining the field will make using it easier and less error prone
in future patches.
There shouldn't be any downside to this: the field fits in what would
otherwise be a 2-byte hole, so we're not saving space by conditionally
leaving it out.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20240913182854.2445457-2-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The single-queue optimized list flush doesn't have an unplug trace event
to pair with the plug event. Add one.
In the unlikely event an error occurs and falls back to the less
optimized plug flush path, it's possible a 2nd unplug trace event will
be logged, but it will show the remainig count that weren't previously
handled.
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20240906194540.3719642-1-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The current setup with bio_may_exceed_limit and __bio_split_to_limits
is a bit of a mess.
Change it so that __bio_split_to_limits does all the work and is just
a variant of bio_split_to_limits that returns nr_segs. This is done
by inlining it and instead have the various bio_split_* helpers directly
submit the potentially split bios.
To support btrfs, the rw version has a lower level helper split out
that just returns the offset to split. This turns out to nicely clean
up the btrfs flow as well.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Sterba <dsterba@suse.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Tested-by: Hans Holmberg <hans.holmberg@wdc.com>
Reviewed-by: Hans Holmberg <hans.holmberg@wdc.com>
Link: https://lore.kernel.org/r/20240826173820.1690925-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When soft interrupt actions are called, they are passed a pointer to the
struct softirq action which contains the action's function pointer.
This pointer isn't useful, as the action callback already knows what
function it is. And since each callback handles a specific soft interrupt,
the callback also knows which soft interrupt number is running.
No soft interrupt action callback actually uses this parameter, so remove
it from the function pointer signature. This clarifies that soft interrupt
actions are global routines and makes it slightly cheaper to call them.
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Link: https://lore.kernel.org/all/20240815171549.3260003-1-csander@purestorage.com
Call .limit_depth() after data->hctx has been set such that data->hctx can
be used in .limit_depth() implementations.
Cc: Christoph Hellwig <hch@lst.de>
Cc: Damien Le Moal <dlemoal@kernel.org>
Cc: Zhiguo Niu <zhiguo.niu@unisoc.com>
Fixes: 07757588e5 ("block/mq-deadline: Reserve 25% of scheduler tags for synchronous requests")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240509170149.7639-2-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
IO logical block size is one fundamental queue limit, and every IO has
to be aligned with logical block size because our bio split can't deal
with unaligned bio.
The check has to be done with queue usage counter grabbed because device
reconfiguration may change logical block size, and we can prevent the
reconfiguration from happening by holding queue usage counter.
logical_block_size stays in the 1st cache line of queue_limits, and this
cache line is always fetched in fast path via bio_may_exceed_limits(),
so IO perf won't be affected by this check.
Cc: Yi Zhang <yi.zhang@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Ye Bin <yebin10@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240620030631.3114026-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently blk_queue_get_max_sectors() is passed a enum req_op. In future
the value returned from blk_queue_get_max_sectors() may depend on certain
request flags, so pass a request pointer.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20240620125359.2684798-2-john.g.garry@oracle.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move the poll flag into the queue_limits feature field so that it can
be set atomically with the queue frozen.
Stacking drivers are simplified in that they now can simply set the
flag, and blk_stack_limits will clear it when the features is not
supported by any of the underlying devices.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20240617060532.127975-22-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move the nowait flag into the queue_limits feature field so that it can
be set atomically with the queue frozen.
Stacking drivers are simplified in that they now can simply set the
flag, and blk_stack_limits will clear it when the features is not
supported by any of the underlying devices.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20240617060532.127975-20-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move the io_stat flag into the queue_limits feature field so that it can
be set atomically with the queue frozen.
Simplify md and dm to set the flag unconditionally instead of avoiding
setting a simple flag for cases where it already is set by other means,
which is a bit pointless.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20240617060532.127975-17-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
queue_attr_store updates attributes used to control generating I/O, and
can cause malformed bios if changed with I/O in flight. Freeze the queue
in common code instead of adding it to almost every attribute.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20240617060532.127975-12-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Block layer integrity configuration is a bit complex right now, as it
indirects through operation vectors for a simple two-dimensional
configuration:
a) the checksum type of none, ip checksum, crc, crc64
b) the presence or absence of a reference tag
Remove the integrity profile, and instead add a separate csum_type flag
which replaces the existing ip-checksum field and a new flag that
indicates the presence of the reference tag.
This removes up to two layers of indirect calls, remove the need to
offload the no-op verification of non-PI metadata to a workqueue and
generally simplifies the code. The downside is that block/t10-pi.c now
has to be built into the kernel when CONFIG_BLK_DEV_INTEGRITY is
supported. Given that both nvme and SCSI require t10-pi.ko, it is loaded
for all usual configurations that enabled CONFIG_BLK_DEV_INTEGRITY
already, though.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240613084839.1044015-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'block-6.10-20240523' of git://git.kernel.dk/linux
Pull more block updates from Jens Axboe:
"Followup block updates, mostly due to NVMe being a bit late to the
party. But nothing major in there, so not a big deal.
In detail, this contains:
- NVMe pull request via Keith:
- Fabrics connection retries (Daniel, Hannes)
- Fabrics logging enhancements (Tokunori)
- RDMA delete optimization (Sagi)
- ublk DMA alignment fix (me)
- null_blk sparse warning fixes (Bart)
- Discard support for brd (Keith)
- blk-cgroup list corruption fixes (Ming)
- blk-cgroup stat propagation fix (Waiman)
- Regression fix for plugging stall with md (Yu)
- Misc fixes or cleanups (David, Jeff, Justin)"
* tag 'block-6.10-20240523' of git://git.kernel.dk/linux: (24 commits)
null_blk: fix null-ptr-dereference while configuring 'power' and 'submit_queues'
blk-throttle: remove unused struct 'avg_latency_bucket'
block: fix lost bio for plug enabled bio based device
block: t10-pi: add MODULE_DESCRIPTION()
blk-mq: add helper for checking if one CPU is mapped to specified hctx
blk-cgroup: Properly propagate the iostat update up the hierarchy
blk-cgroup: fix list corruption from reorder of WRITE ->lqueued
blk-cgroup: fix list corruption from resetting io stat
cdrom: rearrange last_media_change check to avoid unintentional overflow
nbd: Fix signal handling
nbd: Remove a local variable from nbd_send_cmd()
nbd: Improve the documentation of the locking assumptions
nbd: Remove superfluous casts
nbd: Use NULL to represent a pointer
brd: implement discard support
null_blk: Fix two sparse warnings
ublk_drv: set DMA alignment mask to 3
nvme-rdma, nvme-tcp: include max reconnects for reconnect logging
nvmet-rdma: Avoid o(n^2) loop in delete_ctrl
nvme: do not retry authentication failures
...
We can easily have up to 24 flags with sane
atomicity, _without_ pushing anything out
of the first cacheline of struct block_device.
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Merge tag 'pull-bd_flags-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull bdev flags update from Al Viro:
"Compactifying bdev flags.
We can easily have up to 24 flags with sane atomicity, _without_
pushing anything out of the first cacheline of struct block_device"
* tag 'pull-bd_flags-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
bdev: move ->bd_make_it_fail to ->__bd_flags
bdev: move ->bd_ro_warned to ->__bd_flags
bdev: move ->bd_has_subit_bio to ->__bd_flags
bdev: move ->bd_write_holder into ->__bd_flags
bdev: move ->bd_read_only to ->__bd_flags
bdev: infrastructure for flags
wrapper for access to ->bd_partno
Use bdev_is_paritition() instead of open-coding it
Commit a46c27026d ("blk-mq: don't schedule block kworker on isolated CPUs")
rules out isolated CPUs from hctx->cpumask, and hctx->cpumask should only be
used for scheduling kworker.
Add helper blk_mq_cpu_mapped_to_hctx() and apply it into cpuhp handlers.
This patch avoids to forget clearing INACTIVE of hctx state in case that one
isolated CPU becomes online, and fixes hang issue when allocating request
from this hctx's tags.
Cc: Raju Cheerla <rcheerla@redhat.com>
Fixes: a46c27026d ("blk-mq: don't schedule block kworker on isolated CPUs")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20240517020514.149771-1-ming.lei@redhat.com
Tested-by: Raju Cheerla <rcheerla@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently, io_ticks is accounted based on sampling, specifically
update_io_ticks() will always account io_ticks by 1 jiffies from
bdev_start_io_acct()/blk_account_io_start(), and the result can be
inaccurate, for example(HZ is 250):
Test script:
fio -filename=/dev/sda -bs=4k -rw=write -direct=1 -name=test -thinktime=4ms
Test result: util is about 90%, while the disk is really idle.
This behaviour is introduced by commit 5b18b5a737 ("block: delete
part_round_stats and switch to less precise counting"), however, there
was a key point that is missed that this patch also improve performance
a lot:
Before the commit:
part_round_stats:
if (part->stamp != now)
stats |= 1;
part_in_flight()
-> there can be lots of task here in 1 jiffies.
part_round_stats_single()
__part_stat_add()
part->stamp = now;
After the commit:
update_io_ticks:
stamp = part->bd_stamp;
if (time_after(now, stamp))
if (try_cmpxchg())
__part_stat_add()
-> only one task can reach here in 1 jiffies.
Hence in order to account io_ticks precisely, we only need to know if
there are IO inflight at most once in one jiffies. Noted that for
rq-based device, iterating tags should not be used here because
'tags->lock' is grabbed in blk_mq_find_and_get_req(), hence
part_stat_lock_inc/dec() and part_in_flight() is used to trace inflight.
The additional overhead is quite little:
- per cpu add/dec for each IO for rq-based device;
- per cpu sum for each jiffies;
And it's verified by null-blk that there are no performance degration
under heavy IO pressure.
Fixes: 5b18b5a737 ("block: delete part_round_stats and switch to less precise counting")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240509123717.3223892-2-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk_zone_complete_request() must be called to handle the completion of a
zone write request handled with zone write plugging. This function is
called from blk_complete_request(), blk_update_request() and also in
blk_mq_submit_bio() error path. Improve this by moving this function
call into blk_mq_finish_request() as all requests are processed with
this function when they complete as well as when they are freed without
being executed. This also improves blk_update_request() used by scsi
devices as these may repeatedly call this function to handle partial
completions.
To be consistent with this change, blk_zone_complete_request() is
renamed to blk_zone_finish_request() and
blk_zone_write_plug_complete_request() is renamed to
blk_zone_write_plug_finish_request().
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20240501110907.96950-12-dlemoal@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
