We need to check for a valid index before accessing the array
element to avoid accessing invalid memory regions.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Modified by Jens to drop the unlikely(), and make the fall through
path be having a valid tag.
Signed-off-by: Jens Axboe <axboe@fb.com>
We use bio chaining during most I/Os these days due to the delayed
bio splitting. Additionally XFS will start using it, and there is
a pending direct I/O rewrite also making heavy use for it. Don't
pretend it's always unlikely, and let the branch predictor do it's
job instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Replace the while loop that unecessarily checks for a NULL bio in the fast
path with a simple goto loop.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Factor common code between bio_chain_endio and bio_endio into a common
helper.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Only overwrite the parents bi_error if it was zero. That way a successful
bio completion doesn't reset the error pointer.
Reported-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
block_dev's .writepages/.writepage already handles
wbc_init_bio/wbc_account_io. We only set the SB_I_CGROUPWB bit to
suppport writeback cgroup support.
Signed-off-by: Shaohua Li <shli@fb.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
A h/w context's tags are freed if it was not assigned a CPU. Check if
the context has tags before updating the depth.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Currently q->mq_ops is used widely to decide if the queue
is mq or not, so we should set the 'flag' asap so that both
block core and drivers can get the correct mq info.
For example, commit 868f2f0b720(blk-mq: dynamic h/w context count)
moves the hctx's initialization before setting q->mq_ops in
blk_mq_init_allocated_queue(), then cause blk_alloc_flush_queue()
to think the queue is non-mq and don't allocate command size
for the per-hctx flush rq.
This patches should fix the problem reported by Sasha.
Cc: Keith Busch <keith.busch@intel.com>
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Fixes: 868f2f0b72 ("blk-mq: dynamic h/w context count")
Signed-off-by: Jens Axboe <axboe@fb.com>
The new queue limit is not used by the majority of block drivers, and
should be initialized to 0 for the driver's requested settings to be used.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
The hardware's provided queue count may change at runtime with resource
provisioning. This patch allows a block driver to alter the number of
h/w queues available when its resource count changes.
The main part is a new blk-mq API to request a new number of h/w queues
for a given live tag set. The new API freezes all queues using that set,
then adjusts the allocated count prior to remapping these to CPUs.
The bulk of the rest just shifts where h/w contexts and all their
artifacts are allocated and freed.
The number of max h/w contexts is capped to the number of possible cpus
since there is no use for more than that. As such, all pre-allocated
memory for pointers need to account for the max possible rather than
the initial number of queues.
A side effect of this is that the blk-mq will proceed successfully as
long as it can allocate at least one h/w context. Previously it would
fail request queue initialization if less than the requested number
was allocated.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Jon Derrick <jonathan.derrick@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Currently we don't allow sync workload of one cgroup to preempt sync
workload of any other cgroup. This is because we want to achieve service
separation between cgroups. However in cases where cgroup preempting is
ancestor of the current cgroup, there is no need of separation and
idling introduces unnecessary overhead. This hurts for example the case
when workload is isolated within a cgroup but journalling threads are in
root cgroup. Simple way to demostrate the issue is using:
dbench4 -c /usr/share/dbench4/client.txt -t 10 -D /mnt 1
on ext4 filesystem on plain SATA drive (mounted with barrier=0 to make
difference more visible). When all processes are in the root cgroup,
reported throughput is 153.132 MB/sec. When dbench process gets its own
blkio cgroup, reported throughput drops to 26.1006 MB/sec.
Fix the problem by making check in cfq_should_preempt() more benevolent
and allow preemption by ancestor cgroup. This improves the throughput
reported by dbench4 to 48.9106 MB/sec.
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jan Kara <jack@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
The original idea with preemption of sync noidle queues (introduced in
commit 718eee0579 "cfq-iosched: fairness for sync no-idle queues") was
that we service all sync noidle queues together, we don't idle on any of
the queues individually and we idle only if there is no sync noidle
queue to be served. This intention also matches the original test:
if (cfqd->serving_type == SYNC_NOIDLE_WORKLOAD
&& new_cfqq->service_tree == cfqq->service_tree)
return true;
However since at that time cfqq->service_tree was not set for idling
queues, this test was unreliable and was replaced in commit e4a229196a
"cfq-iosched: fix no-idle preemption logic" by:
if (cfqd->serving_type == SYNC_NOIDLE_WORKLOAD &&
cfqq_type(new_cfqq) == SYNC_NOIDLE_WORKLOAD &&
new_cfqq->service_tree->count == 1)
return true;
That was a reliable test but was actually doing something different -
now we preempt sync noidle queue only if the new queue is the only one
busy in the service tree.
These days cfq queue is kept in service tree even if it is idling and
thus the original check would be safe again. But since we actually check
that cfq queues are in the same cgroup, of the same priority class and
workload type (sync noidle), we know that new_cfqq is fine to preempt
cfqq. So just remove the service tree check.
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jan Kara <jack@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Move check for preemption by rt class up. There is no functional change
but it makes arguing about conditions simpler since we can be sure both
cfq queues are from the same ioprio class.
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jan Kara <jack@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
There is no point in idling on a cfq group if the only cfq queue that is
there has too big thinktime.
Signed-off-by: Jan Kara <jack@suse.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
Pull USB driver fixes from Greg KH:
"Here are some small USB fixes and new device ids for 4.5-rc2. Nothing
major here, full details are in the shortlog, and all of these have
been in linux-next successfully"
* tag 'usb-4.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
USB: option: fix Cinterion AHxx enumeration
USB: mxu11x0: fix memory leak on usb_serial private data
USB: serial: ftdi_sio: add support for Yaesu SCU-18 cable
USB: serial: option: Adding support for Telit LE922
USB: serial: visor: fix crash on detecting device without write_urbs
USB: visor: fix null-deref at probe
USB: cp210x: add ID for IAI USB to RS485 adaptor
usb: hub: do not clear BOS field during reset device
cdc-acm:exclude Samsung phone 04e8:685d
usb: cdc-acm: send zero packet for intel 7260 modem
usb: cdc-acm: handle unlinked urb in acm read callback
Pull tty/serial fixes from Greg KH:
"Here are some small tty/serial driver fixes for 4.5-rc2.
They resolve a number of reported problems (the ioctl one specifically
has been pointed out by numerous people) and one patch adds some new
device ids for the 8250_pci driver. All have been in linux-next
successfully"
* tag 'tty-4.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
serial: 8250_pci: Add Intel Broadwell ports
staging/speakup: Use tty_ldisc_ref() for paste kworker
n_tty: Fix unsafe reference to "other" ldisc
tty: Fix unsafe ldisc reference via ioctl(TIOCGETD)
tty: Retry failed reopen if tty teardown in-progress
tty: Wait interruptibly for tty lock on reopen
Pull staging fixes from Greg KH:
"Here are some small staging driver fixes for 4.5-rc2.
One of them predated 4.4-final, but I missed that merge window due to
the holliday. The others fix reported issues that have come up
recently. The tty change is needed for the speakup driver fix and has
the ack of the tty driver maintainer as well, i.e. myself :)
All have been in linux-next with no reported issues"
* tag 'staging-4.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
Staging: speakup: fix read scrolled-back VT
Staging: speakup: Fix getting port information
Revert "Staging: panel: usleep_range is preferred over udelay"
iio: adis_buffer: Fix out-of-bounds memory access
Pull driver core fix from Greg KH:
"Here's a single driver core fix that resolves an issue a lot of users
have been hitting for a while now. It's been tested a lot and has
been in linux-next successfully for a while"
* tag 'driver-core-4.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
base/platform: Fix platform drivers with no probe callback
Pull MIPS fix from Ralf Baechle:
"Just a single revert for a patch which I had upstreamed out of
sequence"
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
Revert "MIPS: bcm63xx: nvram: Remove unused bcm63xx_nvram_get_psi_size() function"
Pull x86 fixes from Thomas Gleixner:
"A bit on the largish side due to a series of fixes for a regression in
the x86 vector management which was introduced in 4.3. This work was
started in December already, but it took some time to fix all corner
cases and a couple of older bugs in that area which were detected
while at it
Aside of that a few platform updates for intel-mid, quark and UV and
two fixes for in the mm code:
- Use proper types for pgprot values to avoid truncation
- Prevent a size truncation in the pageattr code when setting page
attributes for large mappings"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits)
x86/mm/pat: Avoid truncation when converting cpa->numpages to address
x86/mm: Fix types used in pgprot cacheability flags translations
x86/platform/quark: Print boundaries correctly
x86/platform/UV: Remove EFI memmap quirk for UV2+
x86/platform/intel-mid: Join string and fix SoC name
x86/platform/intel-mid: Enable 64-bit build
x86/irq: Plug vector cleanup race
x86/irq: Call irq_force_move_complete with irq descriptor
x86/irq: Remove outgoing CPU from vector cleanup mask
x86/irq: Remove the cpumask allocation from send_cleanup_vector()
x86/irq: Clear move_in_progress before sending cleanup IPI
x86/irq: Remove offline cpus from vector cleanup
x86/irq: Get rid of code duplication
x86/irq: Copy vectormask instead of an AND operation
x86/irq: Check vector allocation early
x86/irq: Reorganize the search in assign_irq_vector
x86/irq: Reorganize the return path in assign_irq_vector
x86/irq: Do not use apic_chip_data.old_domain as temporary buffer
x86/irq: Validate that irq descriptor is still active
x86/irq: Fix a race in x86_vector_free_irqs()
...
Pull timer fixes from Thomas Gleixner:
"The timer departement delivers:
- a regression fix for the NTP code along with a proper selftest
- prevent a spurious timer interrupt in the NOHZ lowres code
- a fix for user space interfaces returning the remaining time on
architectures with CONFIG_TIME_LOW_RES=y
- a few patches to fix COMPILE_TEST fallout"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tick/nohz: Set the correct expiry when switching to nohz/lowres mode
clocksource: Fix dependencies for archs w/o HAS_IOMEM
clocksource: Select CLKSRC_MMIO where needed
tick/sched: Hide unused oneshot timer code
kselftests: timers: Add adjtimex SETOFFSET validity tests
ntp: Fix ADJ_SETOFFSET being used w/ ADJ_NANO
itimers: Handle relative timers with CONFIG_TIME_LOW_RES proper
posix-timers: Handle relative timers with CONFIG_TIME_LOW_RES proper
timerfd: Handle relative timers with CONFIG_TIME_LOW_RES proper
hrtimer: Handle remaining time proper for TIME_LOW_RES
clockevents/tcb_clksrc: Prevent disabling an already disabled clock
Pull scheduler fixes from Thomas Gleixner:
"Three small fixes in the scheduler/core:
- use after free in the numa code
- crash in the numa init code
- a simple spelling fix"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
pid: Fix spelling in comments
sched/numa: Fix use-after-free bug in the task_numa_compare
sched: Fix crash in sched_init_numa()
Pull perf fixes from Thomas Gleixner:
"This is much bigger than typical fixes, but Peter found a category of
races that spurred more fixes and more debugging enhancements. Work
started before the merge window, but got finished only now.
Aside of that this contains the usual small fixes to perf and tools.
Nothing particular exciting"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (43 commits)
perf: Remove/simplify lockdep annotation
perf: Synchronously clean up child events
perf: Untangle 'owner' confusion
perf: Add flags argument to perf_remove_from_context()
perf: Clean up sync_child_event()
perf: Robustify event->owner usage and SMP ordering
perf: Fix STATE_EXIT usage
perf: Update locking order
perf: Remove __free_event()
perf/bpf: Convert perf_event_array to use struct file
perf: Fix NULL deref
perf/x86: De-obfuscate code
perf/x86: Fix uninitialized value usage
perf: Fix race in perf_event_exit_task_context()
perf: Fix orphan hole
perf stat: Do not clean event's private stats
perf hists: Fix HISTC_MEM_DCACHELINE width setting
perf annotate browser: Fix behaviour of Shift-Tab with nothing focussed
perf tests: Remove wrong semicolon in while loop in CQM test
perf: Synchronously free aux pages in case of allocation failure
...
Pull locking fix from Thomas Gleixner:
"A single commit, which makes the rtmutex.wait_lock an irq safe lock.
This prevents a potential deadlock which can be triggered by the rcu
boosting code from rcu_read_unlock()"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
rtmutex: Make wait_lock irq safe
Hannes Reinecke
Christoph Hellwig
Shaohua Li
Keith Busch
Ming Lei
Jan Kara
Linus Torvalds