03 Jul, 2008
2 commits
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Avoid bad things happening if the module has a printk control string in
its name.Signed-off-by: maximilian attems
Signed-off-by: Jens Axboe -
Some block devices support verifying the integrity of requests by way
of checksums or other protection information that is submitted along
with the I/O.This patch implements support for generating and verifying integrity
metadata, as well as correctly merging, splitting and cloning bios and
requests that have this extra information attached.See Documentation/block/data-integrity.txt for more information.
Signed-off-by: Martin K. Petersen
Signed-off-by: Jens Axboe
28 May, 2008
1 commit
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Signed-off-by: Alan D. Brunelle
Signed-off-by: Jens Axboe
01 May, 2008
1 commit
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__FUNCTION__ is gcc specific, use __func__
Signed-off-by: Harvey Harrison
Cc: Jens Axboe
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
29 Apr, 2008
3 commits
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The block I/O + elevator + I/O scheduler code spend a lot of time trying
to merge I/Os -- rightfully so under "normal" circumstances. However,
if one were to know that the incoming I/O stream was /very/ random in
nature, the cycles are wasted.This patch adds a per-request_queue tunable that (when set) disables
merge attempts (beyond the simple one-hit cache check), thus freeing up
a non-trivial amount of CPU cycles.Signed-off-by: Alan D. Brunelle
Signed-off-by: Jens Axboe -
This patch fixes the following build error with UML and gcc 4.3:
...
CC block/elevator.o
/home/bunk/linux/kernel-2.6/git/linux-2.6/block/elevator.c: In function ‘elv_merge’:
/home/bunk/linux/kernel-2.6/git/linux-2.6/block/elevator.c:73: sorry, unimplemented: inlining failed in call to ‘elv_rq_merge_ok’: function body not available
/home/bunk/linux/kernel-2.6/git/linux-2.6/block/elevator.c:103: sorry, unimplemented: called from here
/home/bunk/linux/kernel-2.6/git/linux-2.6/block/elevator.c:73: sorry, unimplemented: inlining failed in call to ‘elv_rq_merge_ok’: function body not available
/home/bunk/linux/kernel-2.6/git/linux-2.6/block/elevator.c:495: sorry, unimplemented: called from here
make[2]: *** [block/elevator.o] Error 1
make[1]: *** [block] Error 2Signed-off-by: Adrian Bunk
Signed-off-by: Jens Axboe -
We can save some atomic ops in the IO path, if we clearly define
the rules of how to modify the queue flags.Signed-off-by: Jens Axboe
19 Feb, 2008
1 commit
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Currently we fail if someone requests a valid io scheduler, but it's
modular and not currently loaded. That can happen from a driver init
asking for a different scheduler, or online switching through sysfs
as requested by a user.This patch makes elevator_get() request_module() to attempt to load
the appropriate module, instead of requiring that done manually.Signed-off-by: Jens Axboe
01 Feb, 2008
1 commit
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Signed-off-by: Jens Axboe
28 Jan, 2008
1 commit
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These DMA drain buffer implementations in drivers are pretty horrible
to do in terms of manipulating the scatterlist. Plus they're being
done at least in drivers/ide and drivers/ata, so we now have code
duplication.The one use case for this, as I understand it is AHCI controllers doing
PIO mode to mmc devices but translating this to DMA at the controller
level.So, what about adding a callback to the block layer that permits the
adding of the drain buffer for the problem devices. The idea is that
you'd do this in slave_configure after you find one of these devices.The beauty of doing it in the block layer is that it quietly adds the
drain buffer to the end of the sg list, so it automatically gets mapped
(and unmapped) without anything unusual having to be done to the
scatterlist in driver/scsi or drivers/ata and without any alteration to
the transfer length.Signed-off-by: James Bottomley
Signed-off-by: Jens Axboe
25 Jan, 2008
3 commits
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Now that the old kobject_init() function is gone, rename
kobject_init_ng() to kobject_init() to clean up the namespace.Cc: Kay Sievers
Signed-off-by: Greg Kroah-Hartman -
Now that the old kobject_add() function is gone, rename kobject_add_ng()
to kobject_add() to clean up the namespace.Cc: Kay Sievers
Signed-off-by: Greg Kroah-Hartman -
This converts the code to use the new kobject functions, cleaning up the
logic in doing so.Cc: Jens Axboe
Cc: Kay Sievers
Signed-off-by: Greg Kroah-Hartman
18 Dec, 2007
1 commit
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elv_register() always returns 0, and there isn't anything it does where
it should return an error (the only error condition is so grave that
it's handled with a BUG_ON).Signed-off-by: Adrian Bunk
Signed-off-by: Jens Axboe
20 Oct, 2007
1 commit
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Signed-off-by: Uwe Kleine-König
Signed-off-by: Adrian Bunk
16 Oct, 2007
2 commits
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This implements functionality to pass down or insert a barrier
in a queue, without having data attached to it. The ->prepare_flush_fn()
infrastructure from data barriers are reused to provide this
functionality.Signed-off-by: Jens Axboe
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We can use this helper in the elevator core for BLKPREP_KILL, and it'll
also be useful for the empty barrier patch.Signed-off-by: Jens Axboe
13 Oct, 2007
1 commit
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A number of different drivers incorrect access the kobject name field
directly. This is not correct as the name might not be in the array.
Use the proper accessor function instead.
24 Jul, 2007
1 commit
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Some of the code has been gradually transitioned to using the proper
struct request_queue, but there's lots left. So do a full sweet of
the kernel and get rid of this typedef and replace its uses with
the proper type.Signed-off-by: Jens Axboe
18 Jul, 2007
1 commit
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kmalloc_node() and kmem_cache_alloc_node() were not available in a zeroing
variant in the past. But with __GFP_ZERO it is possible now to do zeroing
while allocating.Use __GFP_ZERO to remove the explicit clearing of memory via memset whereever
we can.Signed-off-by: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
10 Jul, 2007
1 commit
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elevator
Signed-off-by: Matthias Kaehlcke
Signed-off-by: Andrew Morton
Signed-off-by: Jens Axboe
30 Apr, 2007
1 commit
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It's never grabbed from irq context, so just make it plain spin_lock().
Signed-off-by: Jens Axboe
27 Mar, 2007
1 commit
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Booting 2.6.21-rc3-g45592145 I noticed the following on one of my
machines in the bootlog:io scheduler noop registeredTime: jiffies clocksource has been installed.
io scheduler deadline registered (default)
Looking at block/elevator.c, it appears that elv_register() uses two
consecutive printks in a non-atomic way, leading to the above glitch. The
attached trivial patch fixes this issue, by using a single printk.Signed-off-by: Thibaut VARENE
Signed-off-by: Jens Axboe
12 Feb, 2007
2 commits
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Don't allow elv_dispatch_sort() to mix reads and writes together,
it's rarely a good idea.Signed-off-by: Jens Axboe
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Signed-off-by: Jens Axboe
24 Jan, 2007
1 commit
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A flag was recently added to the elevator code to avoid
performing an unplug when reuests are being re-queued.
The goal of this flag was to avoid a deep recursion that
can occur when re-queueing requests after a SCSI device/host
reset. See http://lkml.org/lkml/2006/5/17/254However, that fix added the flag near the bottom of a case
statement, where an earlier break (in an if statement) could
transport one out of the case, without setting the flag.
This patch sets the flag earlier in the case statement.I re-discovered the deep recursion recently during testing;
I was told that it was a known problem, and the fix to it was
in the kernel I was testing. Indeed it was ... but it didn't
fix the bug. With the patch below, I no longer see the bug.Signed-off by: Linas Vepstas
Signed-off-by: Jens Axboe
Cc: Chris Wright
Signed-off-by: Linus Torvalds
22 Dec, 2006
1 commit
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The recent io scheduler allow_merge commit left the block layer with
no merging, oops. This patch fixes that up.That means the CFQ change needs to be verified again, it might not fix
the original bug now. But that's a seperate thing, I'll double check
that tomorrow.Signed-off-by: Jens Axboe
Signed-off-by: Linus Torvalds
20 Dec, 2006
1 commit
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Currently we allow any merge, even if the io originates from different
processes. This can cause really bad starvation and unfairness, if those
ios happen to be synchronous (reads or direct writes).So add a allow_merge hook to the io scheduler ops, so an io scheduler can
help decide whether a bio/process combination may be merged with an
existing request.Signed-off-by: Jens Axboe
01 Dec, 2006
1 commit
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- ->init_queue() does not need the elevator passed in
- ->put_request() is a hot path and need not have the queue passed in
- cfq_update_io_seektime() does not need cfqd passed inSigned-off-by: Jens Axboe
12 Oct, 2006
2 commits
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elv_iosched_show function iterates other elv_list, hence
elv_list_lock should be got.Signed-off-by: Vasily Tarasov
Signed-off-by: Vasily Tarasov -
We can easily produce search through the elevator list
without introducing additional elevator_type variable.Signed-off-by: Vasily Tarasov
Signed-off-by: Jens Axboe
01 Oct, 2006
7 commits
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As people often look for the copyright in files to see who to mail,
update the link to a neutral one.Signed-off-by: Jens Axboe
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Some were kmalloc_node(), some were still kmalloc(). Change them all to
kmalloc_node().Signed-off-by: Jens Axboe
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It's not needed for anything, so kill the bio passing.
Signed-off-by: Jens Axboe
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As the comments indicates in blkdev.h, we can fold it into ->end_io_data
usage as that is really what ->waiting is. Fixup the users of
blk_end_sync_rq().Signed-off-by: Jens Axboe
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The rbtree sort/lookup/reposition logic is mostly duplicated in
cfq/deadline/as, so move it to the elevator core. The io schedulers
still provide the actual rb root, as we don't want to impose any sort
of specific handling on the schedulers.Introduce the helpers and rb_node in struct request to help migrate the
IO schedulers.Signed-off-by: Jens Axboe
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Right now, every IO scheduler implements its own backmerging (except for
noop, which does no merging). That results in duplicated code for
essentially the same operation, which is never a good thing. This patch
moves the backmerging out of the io schedulers and into the elevator
core. We save 1.6kb of text and as a bonus get backmerging for noop as
well. Win-win!Signed-off-by: Jens Axboe
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Right now ->flags is a bit of a mess: some are request types, and
others are just modifiers. Clean this up by splitting it into
->cmd_type and ->cmd_flags. This allows introduction of generic
Linux block message types, useful for sending generic Linux commands
to block devices.Signed-off-by: Jens Axboe
23 Aug, 2006
1 commit
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An exiting task or process which didn't do I/O yet have no io context,
elv_unregister() should check it is not NULL.Signed-off-by: Oleg Nesterov
Acked-by: Jens Axboe
Signed-off-by: Greg Kroah-Hartman
01 Jul, 2006
1 commit
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Signed-off-by: Jörn Engel
Signed-off-by: Adrian Bunk
