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  1. 28 6月, 2005 3 次提交
    • J
      [PATCH] CFQ io scheduler updates · 3b18152c
      由 Jens Axboe 提交于 
      - Adjust slice values

- Instead of one async queue, one is defined per priority level. This
  prevents kernel threads (such as reiserfs/x and others) that run at
  higher io priority from conflicting with others. Previously, it was a
  coin toss what io prio the async queue got, it was defined by who
  first set up the queue.

- Let a time slice only begin, when the previous slice is completely
  done. Previously we could be somewhat unfair to a new sync slice, if
  the previous slice was async and had several ios queued. This might
  need a little tweaking if throughput suffers a little due to this,
  allowing perhaps an overlap of a single request or so.

- Optimize the calling of kblockd_schedule_work() by doing it only when
  it is strictly necessary (no requests in driver and work left to do).

- Correct sync vs async logic. A 'normal' process can be purely async as
  well, and a flusher can be purely sync as well. Sync or async is now a
  property of the class defined and requests pending. Previously writers
  could be considered sync, when they were really async.

- Get rid of the bit fields in cfqq and crq, use flags instead.

- Various other cleanups and fixes
Signed-off-by: NJens Axboe <axboe@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      3b18152c
    • J
      [PATCH] Fix cfq_find_next_crq() · 3d25f356
      由 Jens Axboe 提交于 
      In cfq_find_next_crq(), cfq tries to find the next request by choosing
one of two requests before and after the current one.  Currently, when
choosing the next request, if there's no next request, the next
candidate is NULL, resulting in selection of the previous request.  This
results in weird scheduling.  Once we reach the end, we always seek
backward.

The correct behavior is using the first request as the next candidate.
cfq_choose_req() already has logics for handling wrapped requests.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJens Axboe <axboe@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      3d25f356
    • J
      [PATCH] Update cfq io scheduler to time sliced design · 22e2c507
      由 Jens Axboe 提交于 
      This updates the CFQ io scheduler to the new time sliced design (cfq
v3).  It provides full process fairness, while giving excellent
aggregate system throughput even for many competing processes.  It
supports io priorities, either inherited from the cpu nice value or set
directly with the ioprio_get/set syscalls.  The latter closely mimic
set/getpriority.

This import is based on my latest from -mm.
Signed-off-by: NJens Axboe <axboe@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      22e2c507
  3. 26 6月, 2005 3 次提交
  5. 24 6月, 2005 12 次提交
  7. 21 6月, 2005 3 次提交
  9. 17 6月, 2005 1 次提交
    • K
      When cfq I/O scheduler is selected, get_request() in __make_request() calls · db3b5848
      由 Kiyoshi Ueda 提交于 
      __cfq_get_queue().  __cfq_get_queue() finds an existing queue (struct
cfq_queue) of the current process for the device and returns it.  If it's not
found, __cfq_get_queue() creates and returns a new one if __cfq_get_queue() is
called with __GFP_WAIT flag, or __cfq_get_queue() returns NULL (this means that
get_request() fails) if no __GFP_WAIT flag.

On the other hand, in __make_request(), get_request() is called without
__GFP_WAIT flag at the first time.  Thus, the get_request() fails when there is
no existing queue, typically when it's called for the first I/O request of the
process to the device.

Though it will be followed by get_request_wait() for general case,
__make_request() will just end the I/O with an error (EWOULDBLOCK) when the
request was for read-ahead.
Signed-off-by: NJens Axboe <axboe@suse.de>
Signed-off-by: NKiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: NJun'ichi Nomura <j-nomura@ce.jp.nec.com>
      db3b5848
  11. 16 6月, 2005 2 次提交
  13. 12 6月, 2005 1 次提交
  15. 09 6月, 2005 1 次提交
  17. 03 6月, 2005 1 次提交
  19. 21 5月, 2005 3 次提交
  21. 17 5月, 2005 3 次提交
    • P
      [PATCH] CDRW/DVD packet writing data corruption fix · 7baeb6a5
      由 Peter Osterlund 提交于 
      I found a bug in the packet writing driver that could cause data
corruption.  The problem arised if the driver got a write request for a
sector in a "zone" it was already working on.  In that case it was supposed
to queue the write request until it was done processing earlier requests
for the same zone, and instead work on some other zone in the mean time.
However, if there was no other zone to work on, the driver would initiate
two packet_data objects for the same zone, causing unpredictable things to
happen.
Signed-off-by: NPeter Osterlund <petero2@telia.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      7baeb6a5
    • P
      [PATCH] Fix root hole in pktcdvd · 118326e9
      由 Peter Osterlund 提交于 
      ioctl_by_bdev may only be used INSIDE the kernel.  If the "arg" argument
refers to memory that is accessed by put_user/get_user in the ioctl
function, the memory needs to be in the kernel address space (that's the
set_fs(KERNEL_DS) doing in the ioctl_by_bdev).  This works on i386 because
even with set_fs(KERNEL_DS) the user space memory is still accessible with
put_user/get_user.  That is not true for s390.  In short the ioctl
implementation of the pktcdvd device driver is horribly broken.
Signed-off-by: NPeter Osterlund <petero2@telia.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      118326e9
    • S
      [PATCH] Fix root hole in raw device · 68f66feb
      由 Stephen Tweedie 提交于 
      [Patch] Fix raw device ioctl pass-through

Raw character devices are supposed to pass ioctls through to the block
devices they are bound to.  Unfortunately, they are using the wrong
function for this: ioctl_by_bdev(), instead of blkdev_ioctl().

ioctl_by_bdev() performs a set_fs(KERNEL_DS) before calling the ioctl,
redirecting the user-space buffer access to the kernel address space.
This is, needless to say, a bad thing.

This was noticed first on s390, where raw IO was non-functioning.  The
s390 driver config does not actually allow raw IO to be enabled, which
was the first part of the problem.  Secondly, the s390 kernel address
space is distinct from user, causing legal raw ioctls to fail.  I've
reproduced this on a kernel built with 4G:4G split on x86, which fails
in the same way (-EFAULT if the address does not exist kernel-side;
returns success without actually populating the user buffer if it does.)

The patch below fixes both the config and address-space problems.  It's
based closely on a patch by Jan Glauber <jang@de.ibm.com>, which has
been tested on s390 at IBM.  I've tested it on x86 4G:4G (split address
space) and x86_64 (common address space).

Kernel-address-space access has been assigned CAN-2005-1264.
Signed-off-by: NStephen Tweedie <sct@redhat.com>
Signed-off-by: NDave Jones <davej@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      68f66feb
  23. 07 5月, 2005 1 次提交
  25. 06 5月, 2005 3 次提交
  27. 04 5月, 2005 3 次提交