Re: [PATCH] remove the mg_disk driver

Any comments? Getting rid of this driver which was never wired up at all would help with some of the pending block work.. On Thu, Apr 06, 2017 at 01:28:46PM +0200, Christoph Hellwig wrote: > This drivers was added in 2008, but as far as a I can tell we never had a > single platform that actually

Re: [PATCH 2/8] target: remove iblock WRITE_SAME passthrough support

Hi Nic, this patch looks fine, and I'll include it for the next post. I'll move some of the explanation in this mail into the patch, though.

Re: [PATCH 2/8] target: remove iblock WRITE_SAME passthrough support

On Mon, 2017-04-10 at 18:08 +0200, Christoph Hellwig wrote: > Use the pscsi driver to support arbitrary command passthrough > instead. > The people who are actively using iblock_execute_write_same_direct() are doing so in the context of ESX VAAI BlockZero, together with EXTENDED_COPY and

Re: [PATCH V3 02/16] block, bfq: add full hierarchical scheduling and cgroups support

> Il giorno 11 apr 2017, alle ore 23:47, Tejun Heo ha scritto: > > Hello, > > On Tue, Apr 11, 2017 at 03:43:01PM +0200, Paolo Valente wrote: >> From: Arianna Avanzini >> >> Add complete support for full hierarchical scheduling, with a cgroups >>

Re: [PATCH] blk-mq: Fix blk_execute_rq_nowait() handling of dying queues

On Wed, Apr 12, 2017 at 7:58 AM, Bart Van Assche wrote: > Although blk_execute_rq_nowait() asks blk_mq_sched_insert_request() > to run the queue, the function that should run the queue > (__blk_mq_delay_run_hw_queue()) skips hardware queues for which > .tags == NULL.

Re: [PATCH v4 6/6] dm rq: Avoid that request processing stalls sporadically

On Tue, Apr 11, 2017 at 06:18:36PM +, Bart Van Assche wrote: > On Tue, 2017-04-11 at 14:03 -0400, Mike Snitzer wrote: > > Rather than working so hard to use DM code against me, your argument > > should be: "blk-mq drivers X, Y and Z rerun the hw queue; this is a well > > established pattern" >

[PATCH] blk-mq: Fix blk_execute_rq_nowait() handling of dying queues

Although blk_execute_rq_nowait() asks blk_mq_sched_insert_request() to run the queue, the function that should run the queue (__blk_mq_delay_run_hw_queue()) skips hardware queues for which .tags == NULL. Since blk_mq_free_tag_set() clears .tags this means if blk_execute_rq_nowait() is called after

Re: [PATCH v5] lightnvn: pblk

On Wed, 2017-04-12 at 00:13 +0200, Javier González wrote: > please point out to any other tools/concerns you may have. Hello Javier, Do you already have an account at https://scan.coverity.com/? Any Linux kernel developer can get an account for free. A full Coverity scan of Linus' tree is

Re: [PATCH v5] lightnvn: pblk

Hi Bart, > On 11 Apr 2017, at 17.19, Bart Van Assche wrote: > > On Tue, 2017-04-11 at 16:31 +0200, Javier González wrote: >> Changes since v4: >> * Rebase on top of Matias' for-4.12/core >> * Fix type implicit conversions reported by sparse (reported by Bart Van >>

Re: [PATCH V3 02/16] block, bfq: add full hierarchical scheduling and cgroups support

Hello, On Tue, Apr 11, 2017 at 03:43:01PM +0200, Paolo Valente wrote: > From: Arianna Avanzini > > Add complete support for full hierarchical scheduling, with a cgroups > interface. Full hierarchical scheduling is implemented through the > 'entity' abstraction: both

[PATCH 1/6] blk-mq: Do not invoke queue operations on a dead queue

The blk-mq debugfs attributes are removed after blk_cleanup_queue() has finished. Since running a queue after a queue has entered the "dead" state is not allowed, disallow this. This patch avoids that an attempt to run a dead queue triggers a kernel crash. Signed-off-by: Bart Van Assche

[PATCH 0/6] blk-mq debugfs patches for kernel v4.12

Hello Jens, Please consider the six patches in this series for kernel v4.12. The first patch in this series is a bug fix for code that has already been queued for kernel v4.12. The second patch implements a change requested by Omar. Patches 3-6 are blk-mq debugfs enhancements. Thanks, Bart.

[PATCH 2/6] blk-mq: Move the "state" debugfs attribute one level down

Move the "state" attribute from the top level to the "mq" directory as requested by Omar. Signed-off-by: Bart Van Assche Cc: Omar Sandoval Cc: Hannes Reinecke --- block/blk-mq-debugfs.c | 9 + 1 file changed, 1 insertion(+), 8

[PATCH 6/6] scsi: Implement blk_mq_ops.show_rq()

Show the SCSI CDB, .eh_eflags and .result for pending SCSI commands in /sys/kernel/debug/block/*/mq/*/dispatch and */rq_list. Signed-off-by: Bart Van Assche Cc: Martin K. Petersen Cc: James Bottomley

[PATCH 4/6] blk-mq: Show operation, cmd_flags and rq_flags names

Show the operation name, .cmd_flags and .rq_flags as names instead of numbers. Signed-off-by: Bart Van Assche Cc: Omar Sandoval Cc: Hannes Reinecke --- block/blk-mq-debugfs.c | 72 +++--- 1

[PATCH 3/6] blk-mq: Make blk_flags_show() callers append a newline character

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 Cc: Omar Sandoval Cc: Hannes Reinecke ---

Re: [PATCH V3 00/16] Introduce the BFQ I/O scheduler

On Tue, 2017-04-11 at 19:37 +0200, Paolo Valente wrote: > Just pushed: > https://github.com/Algodev-github/bfq-mq/tree/add-bfq-mq-logical Thanks! But are you aware that the code on that branch doesn't build? $ make all [ ... ] ERROR: "bfq_mark_bfqq_busy" [block/bfq-wf2q.ko] undefined! ERROR:

Re: [PATCH v4 6/6] dm rq: Avoid that request processing stalls sporadically

On Tue, 2017-04-11 at 14:03 -0400, Mike Snitzer wrote: > Rather than working so hard to use DM code against me, your argument > should be: "blk-mq drivers X, Y and Z rerun the hw queue; this is a well > established pattern" > > I see drivers/nvme/host/fc.c:nvme_fc_start_fcp_op() does. But that

Re: [PATCH v4 6/6] dm rq: Avoid that request processing stalls sporadically

On Tue, Apr 11 2017 at 1:51pm -0400, Bart Van Assche wrote: > On Tue, 2017-04-11 at 13:47 -0400, Mike Snitzer wrote: > > Other drivers will very likely be caught about by > > this blk-mq quirk in the future. > > Hello Mike, > > Are you aware that the requirement

Re: [PATCH 1/3] blk-mq: unify hctx delayed_run_work and run_work

On Mon, 2017-04-10 at 09:54 -0600, Jens Axboe wrote: > void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx) > { > - cancel_work(>run_work); > + cancel_delayed_work(>run_work); > cancel_delayed_work(>delay_work); > set_bit(BLK_MQ_S_STOPPED, >state); > } Hello Jens, I would

Re: [PATCH v4 6/6] dm rq: Avoid that request processing stalls sporadically

On Tue, 2017-04-11 at 13:47 -0400, Mike Snitzer wrote: > Other drivers will very likely be caught about by > this blk-mq quirk in the future. Hello Mike, Are you aware that the requirement that blk-mq drivers rerun the queue after having returned BLK_MQ_RQ_QUEUE_BUSY is a requirement that is

Re: [PATCH v4 6/6] dm rq: Avoid that request processing stalls sporadically

On Tue, Apr 11 2017 at 12:26pm -0400, Bart Van Assche wrote: > On Tue, 2017-04-11 at 12:09 -0400, Mike Snitzer wrote: > > This has no place in dm-mq (or any blk-mq > > driver). If it is needed it should be elevated to blk-mq core to > > trigger

Re: [PATCH V3 00/16] Introduce the BFQ I/O scheduler

> Il giorno 11 apr 2017, alle ore 16:37, Bart Van Assche > ha scritto: > > On Tue, 2017-04-11 at 15:42 +0200, Paolo Valente wrote: >> new patch series, addressing (both) issues raised by Bart [1]. > > Hello Paolo, > > Is there a git tree available somewhere with

Re: RFC: remove REQ_OP_WRITE_SAME

On 04/10/2017 11:07 AM, Christoph Hellwig wrote: > Now that we are using REQ_OP_WRITE_ZEROES for all zeroing needs in the > kernel there is very little use left for REQ_OP_WRITE_SAME. We only > have two callers left, and both just export optional protocol features > to remote systems: DRBD and

Re: bfq-mq performance comparison to cfq

On Mon, Apr 10, 2017 at 11:55:43AM +0200, Paolo Valente wrote: > > > Il giorno 10 apr 2017, alle ore 11:05, Andreas Herrmann > > ha scritto: > > > > Hi Paolo, > > > > I've looked at your WIP branch as of 4.11.0-bfq-mq-rc4-00155-gbce0818 > > and did some fio tests to

Re: [PATCH v4 6/6] dm rq: Avoid that request processing stalls sporadically

On Tue, 2017-04-11 at 12:09 -0400, Mike Snitzer wrote: > This has no place in dm-mq (or any blk-mq > driver). If it is needed it should be elevated to blk-mq core to > trigger blk_mq_delay_run_hw_queue() when BLK_MQ_RQ_QUEUE_BUSY is > returned from blk_mq_ops' .queue_rq. Hello Mike, If the

Re: [PATCH v4 6/6] dm rq: Avoid that request processing stalls sporadically

On Fri, Apr 07 2017 at 2:16pm -0400, Bart Van Assche wrote: > While running the srp-test software I noticed that request > processing stalls sporadically at the beginning of a test, namely > when mkfs is run against a dm-mpath device. Every time when that > happened

Re: WBT for SQ devices interface

On Tue, 11 Apr 2017 11:38:27 +0200, Jan Kara wrote: > when testing my fix for 0-day reports with writeback throttling I came > across somewhat unexpected behavior with user interface of writeback > throttling. So currently if CFQ is used as an IO scheduler, we disable > writeback throttling

Re: [PATCH v5] lightnvn: pblk

On Tue, 2017-04-11 at 16:31 +0200, Javier González wrote: > Changes since v4: > * Rebase on top of Matias' for-4.12/core > * Fix type implicit conversions reported by sparse (reported by Bart Van > Assche) > * Make error and debug statistics long atomic variables. Hello Javier, Thanks for the

Re: [PATCH v5] lightnvm: physical block device (pblk) target

On 04/11/2017 04:31 PM, Javier González wrote: This patch introduces pblk, a host-side translation layer for Open-Channel SSDs to expose them like block devices. The translation layer allows data placement decisions, and I/O scheduling to be managed by the host, enabling users to optimize the

Re: [PATCH V3 00/16] Introduce the BFQ I/O scheduler

On Tue, 2017-04-11 at 15:42 +0200, Paolo Valente wrote: > new patch series, addressing (both) issues raised by Bart [1]. Hello Paolo, Is there a git tree available somewhere with these patches and without the single queue BFQ scheduler? Thanks, Bart.

Re: [PATCH 2/3] lightnvm: fix type checks on rrpc

On 04/11/2017 04:18 PM, Javier González wrote: sector_t is always unsigned, therefore avoid < 0 checks on it. Signed-off-by: Javier González --- drivers/lightnvm/rrpc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/lightnvm/rrpc.c

Re: [PATCH 3/3] lightnvm: convert sprintf into strlcpy

On 04/11/2017 04:18 PM, Javier González wrote: Convert sprintf calls to strlcpy in order to make possible buffer overflow more obvious. Signed-off-by: Javier González --- drivers/lightnvm/core.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git

Re: [PATCH 1/3] lightnvm: clean unused variable

On 04/11/2017 04:18 PM, Javier González wrote: Clean unused variable on lightnvm core. Signed-off-by: Javier González --- drivers/lightnvm/core.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c index eb9ab1a..258007a

[PATCH v5] lightnvn: pblk

Changes since v4: * Rebase on top of Matias' for-4.12/core * Fix type implicit conversions reported by sparse (reported by Bart Van Assche) * Make error and debug statistics long atomic variables. Changes since v3: * Apply Bart's feedback [1] * Implement dynamic L2P optimizations for > 32-bit

[PATCH 7/9] nowait aio: xfs

From: Goldwyn Rodrigues If IOCB_NOWAIT is set, bail if the i_rwsem is not lockable immediately. IF IOMAP_NOWAIT is set, return EAGAIN in xfs_file_iomap_begin if it needs allocation either due to file extension, writing to a hole, or COW or waiting for other DIOs to finish.

[PATCH 4/9] nowait-aio: Introduce IOMAP_NOWAIT

From: Goldwyn Rodrigues IOCB_NOWAIT translates to IOMAP_NOWAIT for iomaps. This is used by XFS in the XFS patch. --- fs/iomap.c| 2 ++ include/linux/iomap.h | 1 + 2 files changed, 3 insertions(+) diff --git a/fs/iomap.c b/fs/iomap.c index

[PATCH 8/9] nowait aio: btrfs

From: Goldwyn Rodrigues Return EAGAIN if any of the following checks fail + i_rwsem is not lockable + NODATACOW or PREALLOC is not set + Cannot nocow at the desired location + Writing beyond end of file which is not allocated Signed-off-by: Goldwyn Rodrigues

[PATCH 6/9] nowait aio: ext4

From: Goldwyn Rodrigues Return EAGAIN if any of the following checks fail for direct I/O: + i_rwsem is lockable + Writing beyond end of file (will trigger allocation) + Blocks are not allocated at the write location Signed-off-by: Goldwyn Rodrigues

[PATCH 5/9] nowait aio: return on congested block device

From: Goldwyn Rodrigues A new flag BIO_NOWAIT is introduced to identify bio's orignating from iocb with IOCB_NOWAIT. This flag indicates to return immediately if a request cannot be made instead of retrying. To facilitate this, QUEUE_FLAG_NOWAIT is set to devices which

[PATCH 9/9] nowait aio: Return -EOPNOTSUPP if filesystem does not support

From: Goldwyn Rodrigues The check is in generic_file_write_iter(), which is called by most filesystems, either through fsops.write_iter() or through the function defined by write_iter(). If not, we perform the check in the defined .write_iter() function which is called for

[PATCH 3/9] nowait aio: return if direct write will trigger writeback

From: Goldwyn Rodrigues Find out if the write will trigger a wait due to writeback. If yes, return -EAGAIN. This introduces a new function filemap_range_has_page() which returns true if the file's mapping has a page within the range mentioned. Return -EINVAL for buffered

[PATCH 2/9] nowait aio: Introduce RWF_NOWAIT

From: Goldwyn Rodrigues This flag informs kernel to bail out if an AIO request will block for reasons such as file allocations, or a writeback triggered, or would block while allocating requests while performing direct I/O. Unfortunately, aio_flags is not checked for

[PATCH 1/9] Use RWF_* flags for AIO operations

From: Goldwyn Rodrigues RWF_* flags is used for preadv2/pwritev2 calls. Port to use it for aio operations as well. For this, aio_rw_flags is introduced in struct iocb (using aio_reserved1) which will carry these flags. This is a precursor to the nowait AIO calls. Note, the

[PATCH 0/9 v5] No wait AIO

Formerly known as non-blocking AIO. This series adds nonblocking feature to asynchronous I/O writes. io_submit() can be delayed because of a number of reason: - Block allocation for files - Data writebacks for direct I/O - Sleeping because of waiting to acquire i_rwsem - Congested block

[PATCH 3/3] lightnvm: convert sprintf into strlcpy

Convert sprintf calls to strlcpy in order to make possible buffer overflow more obvious. Signed-off-by: Javier González --- drivers/lightnvm/core.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c

[PATCH 0/3] lightnvm: small fixes

Last small lightnvm fixes for lightnvm core. These are motivated by Bart's comments on pblk's patch. Javier González (3): lightnvm: clean unused variable lightnvm: fix type checks on rrpc lightnvm: convert sprintf into strlcpy drivers/lightnvm/core.c | 9 +++--

[PATCH 1/3] lightnvm: clean unused variable

Clean unused variable on lightnvm core. Signed-off-by: Javier González --- drivers/lightnvm/core.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c index eb9ab1a..258007a 100644 --- a/drivers/lightnvm/core.c +++

[PATCH 2/3] lightnvm: fix type checks on rrpc

sector_t is always unsigned, therefore avoid < 0 checks on it. Signed-off-by: Javier González --- drivers/lightnvm/rrpc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/lightnvm/rrpc.c b/drivers/lightnvm/rrpc.c index 5dba544..cf0e28a 100644

[PATCH] lightnvm: convert sprintf into strlcpy

Convert sprintf calls to strlcpy in order to make possible buffer overflow more obvious. Signed-off-by: Javier González --- drivers/lightnvm/core.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c

Re: [PATCH] block: Fix list corruption of blk stats callback list

On 04/11/2017 03:29 AM, Jan Kara wrote: > When CFQ calls wbt_disable_default(), it will call > blk_stat_remove_callback() to stop gathering IO statistics for the > purposes of writeback throttling. Later, when request_queue is > unregistered, wbt_exit() will call blk_stat_remove_callback() again >

[PATCH V3 05/16] block, bfq: add more fairness with writes and slow processes

This patch deals with two sources of unfairness, which can also cause high latencies and throughput loss. The first source is related to write requests. Write requests tend to starve read requests, basically because, on one side, writes are slower than reads, whereas, on the other side, storage

[PATCH V3 04/16] block, bfq: modify the peak-rate estimator

Unless the maximum budget B_max that BFQ can assign to a queue is set explicitly by the user, BFQ automatically updates B_max. In particular, BFQ dynamically sets B_max to the number of sectors that can be read, at the current estimated peak rate, during the maximum time, T_max, allowed before a

[PATCH V3 03/16] block, bfq: improve throughput boosting

The feedback-loop algorithm used by BFQ to compute queue (process) budgets is basically a set of three update rules, one for each of the main reasons why a queue may be expired. If many processes suddenly switch from sporadic I/O to greedy and sequential I/O, then these rules are quite slow to

Re: [PATCH v4] lightnvm: pblk

Hi Bart, > On 10 Apr 2017, at 22.35, Bart Van Assche wrote: > > On 04/10/2017 11:36 AM, Javier González wrote: >> Changes since v3: >> * Apply Bart's feedback [1] > > Thanks for having addressed these comments. But please also make sure > that the pblk driver builds

[PATCH V3 08/16] block, bfq: preserve a low latency also with NCQ-capable drives

I/O schedulers typically allow NCQ-capable drives to prefetch I/O requests, as NCQ boosts the throughput exactly by prefetching and internally reordering requests. Unfortunately, as discussed in detail and shown experimentally in [1], this may cause fairness and latency guarantees to be violated.

[PATCH V3 07/16] block, bfq: reduce I/O latency for soft real-time applications

To guarantee a low latency also to the I/O requests issued by soft real-time applications, this patch introduces a further heuristic, which weight-raises (in the sense explained in the previous patch) also the queues associated to applications deemed as soft real-time. To be deemed as soft

[PATCH V3 06/16] block, bfq: improve responsiveness

This patch introduces a simple heuristic to load applications quickly, and to perform the I/O requested by interactive applications just as quickly. To this purpose, both a newly-created queue and a queue associated with an interactive application (we explain in a moment how BFQ decides whether

[PATCH V3 10/16] block, bfq: add Early Queue Merge (EQM)

From: Arianna Avanzini A set of processes may happen to perform interleaved reads, i.e., read requests whose union would give rise to a sequential read pattern. There are two typical cases: first, processes reading fixed-size chunks of data at a fixed distance from

[PATCH V3 13/16] block, bfq: boost the throughput with random I/O on NCQ-capable HDDs

This patch is basically the counterpart, for NCQ-capable rotational devices, of the previous patch. Exactly as the previous patch does on flash-based devices and for any workload, this patch disables device idling on rotational devices, but only for random I/O. In fact, only with these queues

[PATCH V3 14/16] block, bfq: handle bursts of queue activations

From: Arianna Avanzini Many popular I/O-intensive services or applications spawn or reactivate many parallel threads/processes during short time intervals. Examples are systemd during boot or git grep. These services or applications benefit mostly from a high

[PATCH V3 15/16] block, bfq: remove all get and put of I/O contexts

When a bfq queue is set in service and when it is merged, a reference to the I/O context associated with the queue is taken. This reference is then released when the queue is deselected from service or split. More precisely, the release of the reference is postponed to when the scheduler lock is

[PATCH V3 12/16] block, bfq: boost the throughput on NCQ-capable flash-based devices

This patch boosts the throughput on NCQ-capable flash-based devices, while still preserving latency guarantees for interactive and soft real-time applications. The throughput is boosted by just not idling the device when the in-service queue remains empty, even if the queue is sync and has a

[PATCH V3 00/16] Introduce the BFQ I/O scheduler

Hi, new patch series, addressing (both) issues raised by Bart [1]. Thanks, Paolo [1] https://lkml.org/lkml/2017/3/31/393 Arianna Avanzini (4): block, bfq: add full hierarchical scheduling and cgroups support block, bfq: add Early Queue Merge (EQM) block, bfq: reduce idling only in

Re: [PATCH V2 16/16] block, bfq: split bfq-iosched.c into multiple source files

> Il giorno 02 apr 2017, alle ore 12:02, kbuild test robot ha > scritto: > > Hi Paolo, > > [auto build test ERROR on block/for-next] > [also build test ERROR on v4.11-rc4 next-20170331] > [if your patch is applied to the wrong git tree, please drop us a note to > help improve

Re: [PATCH 2/3] lightnvm: make nvm_free static

On 04/10/2017 08:51 PM, Javier González wrote: Prefix the nvm_free static function with a missing static keyword. Signed-off-by: Javier González --- drivers/lightnvm/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/lightnvm/core.c

Re: [PATCH 3/4] lightnvm: bad type conversion for nvme control bits

On 04/07/2017 08:31 PM, Javier González wrote: The NVMe I/O command control bits are 16 bytes, but is interpreted as 32 bytes in the lightnvm user I/O data path. Signed-off-by: Javier González --- drivers/nvme/host/lightnvm.c | 2 +- 1 file changed, 1 insertion(+), 1

Re: [PATCH 1/4] lightnvm: double-clear of dev->lun_map on target init error

On 04/07/2017 08:31 PM, Javier González wrote: The dev->lun_map bits are cleared twice if an target init error occurs. First in the target clean routine, and then next in the nvm_tgt_create error function. Make sure that it is only cleared once by extending nvm_remove_tgt_devi() with a clear

Re: [PATCH 4/4] lightnvm: allow to init targets on factory mode

On 04/07/2017 08:31 PM, Javier González wrote: Target initialization has two responsibilities: creating the target partition and instantiating the target. This patch enables to create a factory partition (e.g., do not trigger recovery on the given target). This is useful for target development

Re: [PATCH 2/4] lightnvm: fix cleanup order of disk on init error

On 04/07/2017 08:31 PM, Javier González wrote: Reorder disk allocation such that the disk structure can be put safely. Signed-off-by: Javier González --- drivers/lightnvm/core.c | 14 +++--- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git

WBT for SQ devices interface

Hi, when testing my fix for 0-day reports with writeback throttling I came across somewhat unexpected behavior with user interface of writeback throttling. So currently if CFQ is used as an IO scheduler, we disable writeback throttling because they don't go well together. However when user has

[PATCH] block: Fix list corruption of blk stats callback list

When CFQ calls wbt_disable_default(), it will call blk_stat_remove_callback() to stop gathering IO statistics for the purposes of writeback throttling. Later, when request_queue is unregistered, wbt_exit() will call blk_stat_remove_callback() again which will try to delete callback from the list

Re: [PATCH V2 00/16] Introduce the BFQ I/O scheduler

> Il giorno 10 apr 2017, alle ore 18:56, Bart Van Assche > ha scritto: > > On Fri, 2017-03-31 at 14:47 +0200, Paolo Valente wrote: >> [ ... ] > > Hello Paolo, > > Is the git tree that is available at https://github.com/Algodev-github/bfq-mq > appropriate for

Re: bfq-mq performance comparison to cfq

> Il giorno 10 apr 2017, alle ore 17:15, Bart Van Assche > ha scritto: > > On Mon, 2017-04-10 at 11:55 +0200, Paolo Valente wrote: >> That said, if you do always want maximum throughput, even at the >> expense of latency, then just switch off low-latency heuristics,

Re: bfq-mq performance comparison to cfq

> Il giorno 10 apr 2017, alle ore 11:55, Paolo Valente > ha scritto: > >> >> Il giorno 10 apr 2017, alle ore 11:05, Andreas Herrmann >> ha scritto: >> >> Hi Paolo, >> >> I've looked at your WIP branch as of 4.11.0-bfq-mq-rc4-00155-gbce0818 >>

Re: [PATCH 1/3] lightnvm: convert sprintf into snprintf

> On 10 Apr 2017, at 20.56, Bart Van Assche wrote: > > On Mon, 2017-04-10 at 20:51 +0200, Javier González wrote: >> Convert sprintf calls to snprintf in order to make possible buffer >> overflow more obvious. >> >> Signed-off-by: Javier González