16 Oct, 2007

2 commits


13 Oct, 2007

1 commit


24 Jul, 2007

1 commit

  • 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

    Jens Axboe
     

18 Jul, 2007

1 commit

  • 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

    Christoph Lameter
     

10 Jul, 2007

1 commit


30 Apr, 2007

1 commit


27 Mar, 2007

1 commit

  • 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

    Thibaut VARENE
     

12 Feb, 2007

2 commits


24 Jan, 2007

1 commit

  • 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/2006/5/17/254

    However, 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

    Linas Vepstas
     

22 Dec, 2006

1 commit

  • 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

    Jens Axboe
     

20 Dec, 2006

1 commit

  • 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

    Jens Axboe
     

01 Dec, 2006

1 commit


12 Oct, 2006

2 commits


01 Oct, 2006

7 commits


23 Aug, 2006

1 commit


01 Jul, 2006

1 commit


23 Jun, 2006

1 commit

  • We already drop the refcount in elevator_exit(), and as
    we're setting 'e' to NULL, we'll never take that branch anyway.
    Finally, as 'e' is a local var that isn't referenced afterwards,
    setting it to NULL is pointless.

    Signed-off-by: Dave Jones
    Signed-off-by: Jens Axboe

    Dave Jones
     

09 Jun, 2006

1 commit

  • There's a race between shutting down one io scheduler and firing up the
    next, in which a new io could enter and cause the io scheduler to be
    invoked with bad or NULL data.

    To fix this, we need to maintain the queue lock for a bit longer.
    Unfortunately we cannot do that, since the elevator init requires to be
    run without the lock held. This isn't easily fixable, without also
    changing the mempool API. So split the initialization into two parts,
    and alloc-init operation and an attach operation. Then we can
    preallocate the io scheduler and related structures, and run the attach
    inside the lock after we detach the old one.

    This patch has survived 30 minutes of 1 second io scheduler switching
    with a very busy io load.

    Signed-off-by: Jens Axboe
    Signed-off-by: Linus Torvalds

    Jens Axboe
     

12 May, 2006

1 commit

  • Don't recurse back into the driver even if the unplug threshold is met,
    when the driver asks for a requeue. This is both silly from a logical
    point of view (requeues typically happen due to driver/hardware
    shortage), and also dangerous since we could hit an endless request_fn
    -> requeue -> unplug -> request_fn loop and crash on stack overrun.

    Also limit blk_run_queue() to one level of recursion, similar to how
    blk_start_queue() works.

    This patch fixed a real problem with SLES10 and lpfc, and it could hit
    any SCSI lld that returns non-zero from it's ->queuecommand() handler.

    Signed-off-by: Jens Axboe
    Signed-off-by: Linus Torvalds

    Jens Axboe
     

20 Apr, 2006

1 commit


01 Apr, 2006

1 commit

  • The boot cmdline is parsed in parse_early_param() and
    parse_args(,unknown_bootoption).

    And __setup() is used in obsolete_checksetup().

    start_kernel()
    -> parse_args()
    -> unknown_bootoption()
    -> obsolete_checksetup()

    If __setup()'s callback (->setup_func()) returns 1 in
    obsolete_checksetup(), obsolete_checksetup() thinks a parameter was
    handled.

    If ->setup_func() returns 0, obsolete_checksetup() tries other
    ->setup_func(). If all ->setup_func() that matched a parameter returns 0,
    a parameter is seted to argv_init[].

    Then, when runing /sbin/init or init=app, argv_init[] is passed to the app.
    If the app doesn't ignore those arguments, it will warning and exit.

    This patch fixes a wrong usage of it, however fixes obvious one only.

    Signed-off-by: OGAWA Hirofumi
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    OGAWA Hirofumi
     

25 Mar, 2006

1 commit


24 Mar, 2006

1 commit


19 Mar, 2006

3 commits


08 Feb, 2006

1 commit

  • q->ordcolor must only be flipped on initial queueing of a hardbarrier
    request.

    Constructing ordered sequence and requeueing used to pass through
    __elv_add_request() which flips q->ordcolor when it sees a barrier
    request.

    This patch separates out elv_insert() from __elv_add_request() and uses
    elv_insert() when constructing ordered sequence and requeueing.
    elv_insert() inserts the given request at the specified position and
    does nothing else.

    Signed-off-by: Tejun Heo
    Acked-by: Jens Axboe
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Tejun Heo
     

06 Feb, 2006

1 commit


24 Jan, 2006

2 commits

  • Jens has decided that allowing the default scheduler to be a module is
    a bug, and should not be allowed under kconfig. However, I find that
    scenario useful for debugging, and wish for the kernel to be able to
    handle this situation without OOPSing, if I enable such an option in
    the .config directly. This patch dynamically checks for the presence
    of the compiled-in default, and falls back to no-op, emitting a
    suitable error message, when the default is not available

    Tested for a range of boot options on 2.6.16-rc1-mm2.

    Signed-off-by: Nate Diller
    Signed-off-by: Jens Axboe

    Nate Diller
     
  • My previous default iosched patch did a poor job dealing with the
    'elevator=' boot-time option. The old behavior falls back to the
    compiled-in default if the requested one is not registered at boot
    time. This patch dynamically evaluates which default
    to use, and emits a suitable error message when the requested scheduler
    is not available. It also does the 'as' -> 'anticipatory' conversion
    before elevator registration, which along with a modified registration
    function, allows it to correctly indicate which default scheduler is
    in use.

    Tested for a range of boot options on 2.6.16-rc1-mm2.

    Signed-off-by: Nate Diller
    Signed-off-by: Jens Axboe

    Nate Diller
     

16 Jan, 2006

1 commit