The only difference between ->run_work and ->delay_work, is that
the latter is used to defer running a queue. This is done by
marking the queue stopped, and scheduling ->delay_work to run
sometime in the future. While the queue is stopped, direct runs
or runs through ->run_work will not run the queue.
If we combine the handlers, then we need to handle two things:
1) If a delayed/stopped run is scheduled, then we should not run
the queue before that has been completed.
2) If a queue is delayed/stopped, the handler needs to restart
the queue. Normally a run of a queue with the stopped bit set
would be a no-op.
Case 1 is handled by modifying a currently pending queue run
to the deadline set by the caller of blk_mq_delay_queue().
Subsequent attempts to queue a queue run will find the work
item already pending, and direct runs will see a stopped queue
as before.
Case 2 is handled by adding a new bit, BLK_MQ_S_START_ON_RUN,
that tells the work handler that it should clear a stopped
queue and run the handler.
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This modifies (or adds, if not currently pending) an existing
delayed work item.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
They serve the exact same purpose. Get rid of the non-delayed
work variant, and just run it without delay for the normal case.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
list_for_each_entry() isn't super safe if we're freeing the objects
while we traverse the list. Also don't bother taking the extra
reference, the module refcounting stuff will save us from having anybody
messing with the device while we're trying to unload.
Reported-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Seems like this was forgotten in the bfq-series from Paolo. Let's do it now
so people don't miss out involving Paolo for any future changes or when
reporting bugs.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
At least one driver, mtip32xx, has a hard coded dependency on
the value of the reserved tag used for internal commands. While
that should really be fixed up, for now let's ensure that we just
bypass the scheduler tags an allocation marked as reserved. They
are used for house keeping or error handling, so we can safely
ignore them in the scheduler.
Tested-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
mtip32xx supposes that 'request_idx' passed to .init_request()
is tag of the request, and use that as request's tag to initialize
command header.
After MQ IO scheduler is in, request tag assigned isn't same with
the request index anymore, so cause strange hardware failure on
mtip32xx, even whole system panic is triggered.
This patch fixes the issue by initializing command header via
request's real tag.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Show the SCSI CDB for pending SCSI commands in
/sys/kernel/debug/block/*/mq/*/dispatch and */rq_list. An example
of how SCSI commands are displayed by this code:
ffff8801703245c0 {.op=READ, .cmd_flags=META PRIO, .rq_flags=DONTPREP IO_STAT STATS, .tag=14, .internal_tag=-1, .cmd=Read(10) 28 00 2a 81 1b 30 00 00 08 00}
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: <linux-scsi@vger.kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
This new callback function will be used in the next patch to show
more information about SCSI requests.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Cc: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Show the operation name, .cmd_flags and .rq_flags as names instead
of numbers.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This patch does not change any functionality but makes it possible
to produce a single line of output with multiple flag-to-name
translations.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Move the "state" attribute from the top level to the "mq" directory
as requested by Omar.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
We currently call blk_mq_free_queue() from blk_cleanup_queue()
before we unregister the debugfs attributes for that queue in
blk_release_queue(). This leaves a window open during which
accessing most of the mq debugfs attributes would cause a
use-after-free. Additionally, the "state" attribute allows
running the queue, which we should not do after the queue has
entered the "dead" state. Fix both cases by unregistering the
debugfs attributes before freeing queue resources starts.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Hctx unregistration involves calling kobject_del(). kobject_del()
must not be called if kobject_add() has not been called. Hence in
the error path only unregister hctxs for which registration succeeded.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Since the blk_mq_debugfs_*register_hctxs() functions register and
unregister all attributes under the "mq" directory, rename these
into blk_mq_debugfs_*register_mq().
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
A later patch will move the call of blk_mq_debugfs_register() to
a function to which the queue name is not passed as an argument.
To avoid having to add a 'name' argument to multiple callers, let
blk_mq_debugfs_register() look up the queue name.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
A later patch in this series will modify blk_mq_debugfs_register()
such that it uses q->kobj.parent to determine the name of a
request queue. Hence make sure that that pointer is initialized
before blk_mq_debugfs_register() is called. To avoid lock inversion,
protect sysfs / debugfs registration with the queue sysfs_lock
instead of the global mutex all_q_mutex.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
The caller only looks at the scsi_request result field anyway.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
ide_pm_execute_rq exectures a PM request synchronously, and in the failure
case where it calls __blk_end_request_all it never checks the error field
passed to the end_io callback, so don't bother setting it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
The SAS transport queues are only used by bsg, and bsg always looks at
the scsi_request results and never add the error passed in the end_io
callback.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
'blks' is malloced in pblk_bb_discovery() and should be freed
before leaving from the nvm_get_tgt_bb_tbl() error handling cases,
otherwise it will cause memory leak. Also skip assign blks to
rlun->bb_list when error.
Fixes: a4bd217b43 ("lightnvm: physical block device (pblk) target")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Fixes: 97b50a654d ("virtio_blk: make SCSI passthrough support configurable")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
When block erases fail, these blocks are marked bad. The number of valid
blocks in the line was not updated, which could cause an infinite loop
on the erase path.
Fix this atomic counter and, in order to avoid taking an irq lock on the
interrupt context, make the erase counters atomic too.
Also, in the case that a significant number of blocks become bad in a
line, the result is the double shared metadata buffer (emeta) to stop
the pipeline until all metadata is flushed to the media. Increase the
number of metadata lines from 2 to 4 to avoid this case.
Fixes: a4bd217b43 "lightnvm: physical block device (pblk) target"
Signed-off-by: Javier González <javier@cnexlabs.com>
Reviewed-by: Matias Bjørling <matias@cnexlabs.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
When a line allocation fails, for example, due to having too many bad
blocks, free its metadata correctly.
Fixes: a4bd217b43 "lightnvm: physical block device (pblk) target"
Signed-off-by: Javier González <javier@cnexlabs.com>
Reviewed-by: Matias Bjørling <matias@cnexlabs.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
When a pblk line fails (or is recovered), make sure to take the line
management lock.
Fixes: a4bd217b43 "lightnvm: physical block device (pblk) target"
Signed-off-by: Javier González <javier@cnexlabs.com>
Reviewed-by: Matias Bjørling <matias@cnexlabs.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
When registering an integrity profile: if the template's interval_exp is
not 0 use it, otherwise use the ilog2() of logical block size of the
provided gendisk.
This fixes a long-standing DM linear target bug where it cannot pass
integrity data to the underlying device if its logical block size
conflicts with the underlying device's logical block size.
Cc: stable@vger.kernel.org
Reported-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Reading from ADDR_EMPTY is out of bounds. The current code generates a
static checker warning because we check for out of bounds "lba" before
we check for ADDR_EMPTY, so the second check is always false. It looks
like we intended ADDR_EMPTY to be a no-op without printing a warning.
Fixes: a4bd217b43 ("lightnvm: physical block device (pblk) target")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This is a static checker fix, and perhaps not a real bug. The static
checker thinks that nr_secs could be negative. It would result in
zeroing more memory than intended. Anyway, even if it's not a bug,
changing this variable to unsigned makes the code easier to audit.
Fixes: a4bd217b43 ("lightnvm: physical block device (pblk) target")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Commit 25520d55cd ("block: Inline blk_integrity in struct gendisk")
introduced blk_integrity_revalidate(), which seems to assume ownership
of the stable pages flag and unilaterally clears it if no blk_integrity
profile is registered:
if (bi->profile)
disk->queue->backing_dev_info->capabilities |=
BDI_CAP_STABLE_WRITES;
else
disk->queue->backing_dev_info->capabilities &=
~BDI_CAP_STABLE_WRITES;
It's called from revalidate_disk() and rescan_partitions(), making it
impossible to enable stable pages for drivers that support partitions
and don't use blk_integrity: while the call in revalidate_disk() can be
trivially worked around (see zram, which doesn't support partitions and
hence gets away with zram_revalidate_disk()), rescan_partitions() can
be triggered from userspace at any time. This breaks rbd, where the
ceph messenger is responsible for generating/verifying CRCs.
Since blk_integrity_{un,}register() "must" be used for (un)registering
the integrity profile with the block layer, move BDI_CAP_STABLE_WRITES
setting there. This way drivers that call blk_integrity_register() and
use integrity infrastructure won't interfere with drivers that don't
but still want stable pages.
Fixes: 25520d55cd ("block: Inline blk_integrity in struct gendisk")
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org # 4.4+, needs backporting
Tested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
From userspace calling ioctl(NVM_DEV_CREATE) was returning ENOMEM for
invalid arguments even though pblk (pblk_init) was returning correctly
-EINVAL to nvm_create_tgt inside core. This patch propagates the
correct return value to userspace.
Because pblk was introduced recently this only needs to go in 4.12.
Fixes: a4bd217b43 ("lightnvm: physical block device (pblk) target")
Signed-off-by: Rakesh Pandit <rakesh@tuxera.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Avoid that the following kernel bug gets triggered:
BUG: sleeping function called from invalid context at ./include/linux/buffer_head.h:349
in_atomic(): 1, irqs_disabled(): 0, pid: 8019, name: find
CPU: 10 PID: 8019 Comm: find Tainted: G W I 4.11.0-rc4-dbg+ #2
Call Trace:
dump_stack+0x68/0x93
___might_sleep+0x16e/0x230
__might_sleep+0x4a/0x80
__ext4_get_inode_loc+0x1e0/0x4e0
ext4_iget+0x70/0xbc0
ext4_iget_normal+0x2f/0x40
ext4_lookup+0xb6/0x1f0
lookup_slow+0x104/0x1e0
walk_component+0x19a/0x330
path_lookupat+0x4b/0x100
filename_lookup+0x9a/0x110
user_path_at_empty+0x36/0x40
vfs_statx+0x67/0xc0
SYSC_newfstatat+0x20/0x40
SyS_newfstatat+0xe/0x10
entry_SYSCALL_64_fastpath+0x18/0xad
This happens since the big if/else in blk_mq_make_request() doesn't
have final else section that also drops the ctx. Add that.
Fixes: b00c53e8f4 ("blk-mq: fix schedule-while-atomic with scheduler attached")
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Omar Sandoval <osandov@fb.com>
Added a bit more to the commit log.
Signed-off-by: Jens Axboe <axboe@fb.com>
Christoph writes:
This is the current NVMe pile: virtualization extensions, lots of FC
updates and various misc bits. There are a few more FC bits that didn't
make the cut, but we'd like to get this request out before the merge
window for sure.
We need to get the command payload from the request before
we attempt to dereference it.
Fixes: 4dda4735c5 ("mtip32xx: add a status field to struct mtip_cmd")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Currently most IOs which return the nvme error codes are retried on
the other path if those IOs returns EIO from NVMe driver. This
patch let Multipath distinguish nvme media error codes and some
generic or cmd-specific nvme error codes so that multipath will
not retry those kinds of IO, to save bandwidth.
Signed-off-by: Junxiong Guan <guanjunxiong@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
If an IO timeout occurs, it's helpful to know if the controller did not
post a completion or the driver missed an interrupt. While we never expect
the latter, this patch will make it possible to tell the difference so
we don't have to guess.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
The FC-NVME spec revised syntax to avoid comma separators.
Sync with the change in the parser for traddr on port attachments.
Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
remoteport teardown never aborted the LS opertions. Add support.
Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Link LS's on the remoteport rather than the controller. LS's are
between nport's. Makes more sense, especially on async teardown where
the controller is torn down regardless of the LS (LS is more of a notifier
to the target of the teardown), to have them on the remoteport.
While revising ls send/done routines, issues were seen relative to
refcounting and cleanup, especially in async path. Reworked these code
paths.
Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
target transport:
----------------------
There are cases when there is a need to abort in-progress target
operations (writedata) so that controller termination or errors can
clean up. That can't happen currently as the abort is another target
op type, so it can't be used till the running one finishes (and it may
not). Solve by removing the abort op type and creating a separate
downcall from the transport to the lldd to request an io to be aborted.
The transport will abort ios on queue teardown or io errors. In general
the transport tries to call the lldd abort only when the io state is
idle. Meaning: ops that transmit data (readdata or rsp) will always
finish their transmit (or the lldd will see a state on the
link or initiator port that fails the transmit) and the done call for
the operation will occur. The transport will wait for the op done
upcall before calling the abort function, and as the io is idle, the
io can be cleaned up immediately after the abort call; Similarly, ios
that are not waiting for data or transmitting data must be in the nvmet
layer being processed. The transport will wait for the nvmet layer
completion before calling the abort function, and as the io is idle,
the io can be cleaned up immediately after the abort call; As for ops
that are waiting for data (writedata), they may be outstanding
indefinitely if the lldd doesn't see a condition where the initiatior
port or link is bad. In those cases, the transport will call the abort
function and wait for the lldd's op done upcall for the operation, where
it will then clean up the io.
Additionally, if a lldd receives an ABTS and matches it to an outstanding
request in the transport, A new new transport upcall was created to abort
the outstanding request in the transport. The transport expects any
outstanding op call (readdata or writedata) will completed by the lldd and
the operation upcall made. The transport doesn't act on the reported
abort (e.g. clean up the io) until an op done upcall occurs, a new op is
attempted, or the nvmet layer completes the io processing.
fcloop:
----------------------
Updated to support the new target apis.
On fcp io aborts from the initiator, the loopback context is updated to
NULL out the half that has completed. The initiator side is immediately
called after the abort request with an io completion (abort status).
On fcp io aborts from the target, the io is stopped and the initiator side
sees it as an aborted io. Target side ops, perhaps in progress while the
initiator side is done, continue but noop the data movement as there's no
structure on the initiator side to reference.
patch also contains:
----------------------
Revised lpfc to support the new abort api
commonized rsp buffer syncing and nulling of private data based on
calling paths.
errors in op done calls don't take action on the fod. They're bad
operations which implies the fod may be bad.
Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Current design has the fcloop job struct, used for both initiator and
target processing, allocated as part of the initiator request structure.
On aborts, the initiator side (based on the request) may terminate, yet
the target side wants to continue processing. the target side can't do
that if the initiator side goes away.
Revise fcloop to allocate an independent target side structure when it
starts an io from the initiator.
Added a lock to the request struct as well to synchronize pointer updates
on abort calls.
Modified target downcalls to recognize conditions where initiator has
aborted the io (thus nulled the pointer between job structs), thus
avoid referencing sgl lists which are gone and no longer making upcalls
to the initiator.
In conditions where the targetport is no longer connected, have the
initiator return an access failure rather than simulating a command
completion.
Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
With the advent of the opdone calls changing context, the lldd can no
longer assume that once the op->done call returns for RSP operations
that the request struct is no longer being accessed.
As such, revise the lldd api for a req_release callback that the
transport will call when the job is complete. This will also be used
with abort cases.
Fixed text in api header for change in io complete semantics.
Revised lpfc to support the new req_release api.
Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Two new feature flags were added to control whether upcalls to the
transport result in context switches or stay in the calling context.
NVMET_FCTGTFEAT_CMD_IN_ISR:
By default, if the flag is not set, the transport assumes the
lldd is in a non-isr context and in the cpu context it should be
for the io queue. As such, the cmd handler is called directly in the
calling context.
If the flag is set, indicating the upcall is an isr context, the
transport mandates a transition to a workqueue. The workqueue assigned
to the queue is used for the context.
NVMET_FCTGTFEAT_OPDONE_IN_ISR
By default, if the flag is not set, the transport assumes the
lldd is in a non-isr context and in the cpu context it should be
for the io queue. As such, the fcp operation done callback is called
directly in the calling context.
If the flag is set, indicating the upcall is an isr context, the
transport mandates a transition to a workqueue. The workqueue assigned
to the queue is used for the context.
Updated lpfc for flags
Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
This is safer as it doesn't rely on the data being stored in
a single page in an sgl.
It also aids our effort to start phasing out users of sg_page. See [1].
For this we kmalloc some memory, copy to it and free at the end. Note:
we can't allocate this memory on the stack as the kbuild test robot
reports some frame size overflows on i386.
[1] https://lwn.net/Articles/720053/
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
This change provides a mechanism to reduce the number of MMIO doorbell
writes for the NVMe driver. When running in a virtualized environment
like QEMU, the cost of an MMIO is quite hefy here. The main idea for
the patch is provide the device two memory location locations:
1) to store the doorbell values so they can be lookup without the doorbell
MMIO write
2) to store an event index.
I believe the doorbell value is obvious, the event index not so much.
Similar to the virtio specification, the virtual device can tell the
driver (guest OS) not to write MMIO unless you are writing past this
value.
FYI: doorbell values are written by the nvme driver (guest OS) and the
event index is written by the virtual device (host OS).
The patch implements a new admin command that will communicate where
these two memory locations reside. If the command fails, the nvme
driver will work as before without any optimizations.
Contributions:
Eric Northup <digitaleric@google.com>
Frank Swiderski <fes@google.com>
Ted Tso <tytso@mit.edu>
Keith Busch <keith.busch@intel.com>
Just to give an idea on the performance boost with the vendor
extension: Running fio [1], a stock NVMe driver I get about 200K read
IOPs with my vendor patch I get about 1000K read IOPs. This was
running with a null device i.e. the backing device simply returned
success on every read IO request.
[1] Running on a 4 core machine:
fio --time_based --name=benchmark --runtime=30
--filename=/dev/nvme0n1 --nrfiles=1 --ioengine=libaio --iodepth=32
--direct=1 --invalidate=1 --verify=0 --verify_fatal=0 --numjobs=4
--rw=randread --blocksize=4k --randrepeat=false
Signed-off-by: Rob Nelson <rlnelson@google.com>
[mlin: port for upstream]
Signed-off-by: Ming Lin <mlin@kernel.org>
[koike: updated for upstream]
Signed-off-by: Helen Koike <helen.koike@collabora.co.uk>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <keith.busch@intel.com>
The QPRIO field is only valid if weighted round robin arbitration is used,
and this driver doesn't enable that controller configuration option.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
No point in providing and exporting this helper. There's just
one (real) user of it, just use rq_data_dir().
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
I lack the basic understanding of what segments mean, so we were being
limited to 512kib requests even with higher max_sectors sizes set.
Setting the maximum number of segments to unlimited allows us to
actually have arbitrarily large IO's go through NBD.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Jens Axboe