Once we mark the queue as needing a restart, re-check if we can
get a driver tag. This fixes a theoretical issue where the needed
IO completes _after_ blk_mq_get_driver_tag() fails, but before we
manage to set the restart bit.
Signed-off-by: Jens Axboe <axboe@fb.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Tested-by: Hannes Reinecke <hare@suse.com>
We'll use the same criteria for whether we need to run the queue sync
or async when we have a scheduler, as we do without one.
Signed-off-by: Jens Axboe <axboe@fb.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Tested-by: Hannes Reinecke <hare@suse.com>
These counters aren't as out-of-place in sysfs as the other stuff, but
debugfs is a slightly better home for them.
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
These statistics _might_ be useful to userspace, but it's better not to
commit to an ABI for these yet. Also, the dispatched file in sysfs
couldn't be cleared, so make it clearable like the others in debugfs.
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
These can be used to debug issues like tag leaks and stuck requests.
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
These are very tied to the blk-mq tag implementation, so exposing them
to sysfs isn't a great idea. Move the debugging information to debugfs
and add basic entries for the number of tags and the number of reserved
tags to sysfs.
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This is useful for debugging problems where we've gotten stuck with
requests in the software queues.
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This is useful debugging information that will be used in the blk-mq
debugfs directory.
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Changed 'weight' to 'busy'.
Signed-off-by: Jens Axboe <axboe@fb.com>
The request pointers by themselves aren't super useful.
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
These lists are only useful for debugging; they definitely don't belong
in sysfs. Putting them in debugfs also removes the limitation of a
single page of output.
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
hctx->state could come in handy for bugs where the hardware queue gets
stuck in the stopped state, and hctx->flags is just useful to know.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
In preparation for putting blk-mq debugging information in debugfs,
create a directory tree mirroring the one in sysfs:
# tree -d /sys/kernel/debug/block
/sys/kernel/debug/block
|-- nvme0n1
| `-- mq
| |-- 0
| | `-- cpu0
| |-- 1
| | `-- cpu1
| |-- 2
| | `-- cpu2
| `-- 3
| `-- cpu3
`-- vda
`-- mq
`-- 0
|-- cpu0
|-- cpu1
|-- cpu2
`-- cpu3
Also add the scaffolding for the actual files that will go in here,
either under the hardware queue or software queue directories.
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
We don't trigger this from the normal IO path, since we always use
blocking allocations from there. But Bart saw it testing multipath
dm, since that is a heavy user of atomic request allocations in
the map and clone path.
Reported-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
If we come in from blk_mq_alloc_requst() with NOWAIT set in flags,
we must ensure that we don't later overwrite that in
blk_mq_sched_get_request(). Initialize alloc_data->flags before
passing it in.
Reported-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
If we have a scheduler attached, we have two sets of tags. We don't
want to apply our active queue throttling for the scheduler side
of tags, that only applies to driver tags since that's the resource
we need to dispatch an IO.
Signed-off-by: Jens Axboe <axboe@fb.com>
The script "checkpatch.pl" pointed information out like the following.
ERROR: do not use assignment in if condition
Thus fix the affected source code place.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Jens Axboe <axboe@fb.com>
The script "checkpatch.pl" pointed information out like the following.
ERROR: do not use assignment in if condition
Thus fix the affected source code places.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Pull x86 fix from Thomas Gleixner:
"Restore the retrigger callbacks in the IO APIC irq chips. That
addresses a long standing regression which got introduced with the
rewrite of the x86 irq subsystem two years ago and went unnoticed so
far"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/ioapic: Restore IO-APIC irq_chip retrigger callback
Pull smp/hotplug fix from Thomas Gleixner:
"Remove an unused variable which is a leftover from the notifier
removal"
* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
cpu/hotplug: Remove unused but set variable in _cpu_down()
Pull virtio/vhost fixes from Michael Tsirkin:
"Random fixes and cleanups that accumulated over the time"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
virtio/s390: virtio: constify virtio_config_ops structures
virtio/s390: add missing \n to end of dev_err message
virtio/s390: support READ_STATUS command for virtio-ccw
tools/virtio/ringtest: tweaks for s390
tools/virtio/ringtest: fix run-on-all.sh for offline cpus
virtio_console: fix a crash in config_work_handler
vhost/scsi: silence uninitialized variable warning
vhost: scsi: constify target_core_fabric_ops structures
Pull thermal management fixes from Zhang Rui:
- fix a regression that thermal zone dynamically allocated sysfs
attributes are freed before they're removed, which is introduced in
4.10-rc1 (Jacob von Chorus)
- fix a boot warning because deprecated hwmon API is used (Fabio
Estevam)
- a couple of fixes for rockchip thermal driver (Brian Norris, Caesar
Wang)
* 'for-rc' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux:
thermal: rockchip: fixes the conversion table
thermal: core: move tz->device.groups cleanup to thermal_release
thermal: thermal_hwmon: Convert to hwmon_device_register_with_info()
thermal: rockchip: handle set_trips without the trip points
thermal: rockchip: optimize the conversion table
thermal: rockchip: fixes invalid temperature case
thermal: rockchip: don't pass table structs by value
thermal: rockchip: improve conversion error messages
Pull USB fixes from Greg KH:
"Here are a few small USB fixes for 4.10-rc5.
Most of these are gadget/dwc2 fixes for reported issues, all of these
have been in linux-next for a while. The last one is a single xhci
WARN_ON removal to handle an issue that the dwc3 driver is hitting in
the 4.10-rc tree. The warning is harmless and needs to be removed, and
a "real" fix that is more complex will show up in 4.11-rc1 for this
device.
That last patch hasn't been in linux-next yet due to the weekend
timing, but it's a "simple" WARN_ON() removal so what could go wrong?
:)"
Famous last words.
* tag 'usb-4.10-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
xhci: remove WARN_ON if dma mask is not set for platform devices
usb: dwc2: host: fix Wmaybe-uninitialized warning
usb: dwc2: gadget: Fix GUSBCFG.USBTRDTIM value
usb: gadget: udc: atmel: remove memory leak
usb: dwc3: exynos fix axius clock error path to do cleanup
usb: dwc2: Avoid suspending if we're in gadget mode
usb: dwc2: use u32 for DT binding parameters
usb: gadget: f_fs: Fix iterations on endpoints.
usb: dwc2: gadget: Fix DMA memory freeing
usb: gadget: composite: Fix function used to free memory
Pull libnvdimm fixes from Dan Williams:
"Two fixes:
- a regression fix for the multiple-pmem-namespace-per-region support
added in 4.9. Even if an existing environment is not using that
feature the act of creating and a destroying a single namespace
with the ndctl utility will lead to the proliferation of extra
unwanted namespace devices.
- a fix for the error code returned from the pmem driver when the
memcpy_mcsafe() routine returns -EFAULT. Btrfs seems to be the only
block I/O consumer that tries to parse the meaning of the error
code when it is non-zero.
Neither of these fixes are critical, the namespace leak is awkward in
that it can cause device naming to change and complicates debugging
namespace initialization issues. The error code fix is included out of
caution for what other consumers might be expecting -EIO for block I/O
errors"
* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
libnvdimm, namespace: fix pmem namespace leak, delete when size set to zero
pmem: return EIO on read_pmem() failure
Jens Axboe
Omar Sandoval
Markus Elfring
Alexander Potapenko
Linus Torvalds