14 Apr, 2016

1 commit


13 Apr, 2016

35 commits

  • This patch adds a check on nvme_watchdog_timer() function to avoid the
    call to reset_work() when an error recovery process is ongoing on
    controller. The check is made by looking at pci_channel_offline()
    result.

    If we don't check for this on nvme_watchdog_timer(), error recovery
    mechanism can't recover well, because reset_work() won't be able to
    do its job (since we're in the middle of an error) and so the
    controller is removed from the system before error recovery mechanism
    can perform slot reset (which would allow the adapter to recover).

    In this patch we also have split the huge condition expression on
    nvme_watchdog_timer() by introducing an auxiliary function to help
    make the code more readable.

    Reviewed-by: Keith Busch
    Reviewed-by: Johannes Thumshirn
    Signed-off-by: Guilherme G. Piccoli
    Signed-off-by: Jens Axboe

    Guilherme G. Piccoli
     
  • Depending on options, we might not be using dev in nvme_cancel_io():

    drivers/nvme/host/pci.c: In function ‘nvme_cancel_io’:
    drivers/nvme/host/pci.c:970:19: warning: unused variable ‘dev’ [-Wunused-variable]
    struct nvme_dev *dev = data;
    ^

    So get rid of it, and just cast for the dev_dbg_ratelimited() call.

    Fixes: 82b4552b91c4 ("nvme: Use blk-mq helper for IO termination")
    Signed-off-by: Jens Axboe

    Jens Axboe
     
  • We don't have any drivers left using it, so kill it off. Update
    documentation to use the newer blk_queue_write_cache().

    Signed-off-by: Jens Axboe
    Reviewed-by: Christoph Hellwig

    Jens Axboe
     
  • Signed-off-by: Jens Axboe
    Reviewed-by: Christoph Hellwig

    Jens Axboe
     
  • Signed-off-by: Jens Axboe
    Reviewed-by: Christoph Hellwig

    Jens Axboe
     
  • Signed-off-by: Jens Axboe
    Reviewed-by: Christoph Hellwig

    Jens Axboe
     
  • Signed-off-by: Jens Axboe
    Reviewed-by: Christoph Hellwig

    Jens Axboe
     
  • Signed-off-by: Jens Axboe
    Reviewed-by: Christoph Hellwig

    Jens Axboe
     
  • Signed-off-by: Jens Axboe
    Reviewed-by: Christoph Hellwig

    Jens Axboe
     
  • Signed-off-by: Jens Axboe
    Reviewed-by: Christoph Hellwig

    Jens Axboe
     
  • Signed-off-by: Jens Axboe
    Reviewed-by: Christoph Hellwig

    Jens Axboe
     
  • Signed-off-by: Jens Axboe
    Reviewed-by: Christoph Hellwig

    Jens Axboe
     
  • Signed-off-by: Jens Axboe
    Reviewed-by: Christoph Hellwig

    Jens Axboe
     
  • Signed-off-by: Jens Axboe
    Reviewed-by: Christoph Hellwig

    Jens Axboe
     
  • Signed-off-by: Jens Axboe
    Reviewed-by: Christoph Hellwig

    Jens Axboe
     
  • Signed-off-by: Jens Axboe
    Reviewed-by: Christoph Hellwig

    Jens Axboe
     
  • The driver calls it with 0 for flags, since it doesn't have a writeback
    cache. Just remove the call, as it's a no-op right now.

    Signed-off-by: Jens Axboe
    Reviewed-by: Christoph Hellwig

    Jens Axboe
     
  • Signed-off-by: Jens Axboe
    Reviewed-by: Christoph Hellwig

    Jens Axboe
     
  • Signed-off-by: Jens Axboe
    Reviewed-by: Christoph Hellwig

    Jens Axboe
     
  • Reviewed-by: Christoph Hellwig
    Signed-off-by: Jens Axboe

    Jens Axboe
     
  • Switch to the newer interface, instead of using blk_queue_flush()
    directly.

    Signed-off-by: Jens Axboe
    Reviewed-by: Christoph Hellwig
    Acked-by: Martin K. Petersen

    Jens Axboe
     
  • Jens Axboe
     
  • Add an internal helper and flag for setting whether a queue has
    write back caching, or write through (or none). Add a sysfs file
    to show this as well, and make it changeable from user space.

    This will replace the (awkward) blk_queue_flush() interface that
    drivers currently use to inform the block layer of write cache state
    and capabilities.

    Signed-off-by: Jens Axboe
    Reviewed-by: Christoph Hellwig

    Jens Axboe
     
  • No caller outside the blk-mq code so we can settle
    with it static.

    Signed-off-by: Sagi Grimberg
    Reviewed-by: Christoph Hellwig
    Reviewed-by: Johannes Thumshirn
    Signed-off-by: Jens Axboe

    Sagi Grimberg
     
  • Only a single tags array anyway.

    Signed-off-by: Keith Busch
    Reviewed-by: Johannes Thumshirn
    Signed-off-by: Sagi Grimberg
    Reviewed-by: Christoph Hellwig
    Signed-off-by: Jens Axboe

    Keith Busch
     
  • blk-mq offers a tagset iterator so let's use that
    instead of using nvme_clear_queues.

    Note, we changed nvme_queue_cancel_ios name to nvme_cancel_io
    as there is no concept of a queue now in this function (we
    also lost the print).

    Signed-off-by: Sagi Grimberg
    Reviewed-by: Christoph Hellwig
    Acked-by: Keith Busch
    Reviewed-by: Johannes Thumshirn
    Signed-off-by: Jens Axboe

    Sagi Grimberg
     
  • If the controller is degraded, the driver should stay out of the way so
    the user can recover the drive. This patch skips driver initiated async
    event requests when the drive is in this state.

    Signed-off-by: Keith Busch
    Reviewed-by: Sagi Grimberg
    Reviewed-by: Christoph Hellwig
    Signed-off-by: Jens Axboe

    Keith Busch
     
  • This moves nvme_setup_{flush,discard,rw} calls into a common
    nvme_setup_cmd() helper. So we can eventually hide all the command
    setup in the core module and don't even need to update the fabrics
    drivers for any specific command type.

    Signed-off-by: Ming Lin
    Reviewed-by: Christoph Hellwig
    Signed-off-by: Jens Axboe

    Ming Lin
     
  • This rewrites nvme_setup_discard() with blk_add_request_payload().
    It allocates only the necessary amount(16 bytes) for the payload.

    Signed-off-by: Ming Lin
    Reviewed-by: Christoph Hellwig
    Signed-off-by: Jens Axboe

    Ming Lin
     
  • The helper returns the number of bytes that need to be mapped
    using PRPs/SGL entries.

    Signed-off-by: Ming Lin
    Reviewed-by: Christoph Hellwig
    Signed-off-by: Jens Axboe

    Ming Lin
     
  • When unloading driver, nvme_disable_io_queues() calls nvme_delete_queue()
    that sends nvme_admin_delete_cq command to admin sq. So when the command
    completed, the lock acquired by nvme_irq() actually belongs to admin queue.

    While the lock that nvme_del_cq_end() trying to acquire belongs to io queue.
    So it will not deadlock.

    This patch adds lock nesting notation to fix following report.

    [ 109.840952] =============================================
    [ 109.846379] [ INFO: possible recursive locking detected ]
    [ 109.851806] 4.5.0+ #180 Tainted: G E
    [ 109.856533] ---------------------------------------------
    [ 109.861958] swapper/0/0 is trying to acquire lock:
    [ 109.866771] (&(&nvmeq->q_lock)->rlock){-.....}, at: [] nvme_del_cq_end+0x26/0x70 [nvme]
    [ 109.876535]
    [ 109.876535] but task is already holding lock:
    [ 109.882398] (&(&nvmeq->q_lock)->rlock){-.....}, at: [] nvme_irq+0x1b/0x50 [nvme]
    [ 109.891547]
    [ 109.891547] other info that might help us debug this:
    [ 109.898107] Possible unsafe locking scenario:
    [ 109.898107]
    [ 109.904056] CPU0
    [ 109.906515] ----
    [ 109.908974] lock(&(&nvmeq->q_lock)->rlock);
    [ 109.913381] lock(&(&nvmeq->q_lock)->rlock);
    [ 109.917787]
    [ 109.917787] *** DEADLOCK ***
    [ 109.917787]
    [ 109.923738] May be due to missing lock nesting notation
    [ 109.923738]
    [ 109.930558] 1 lock held by swapper/0/0:
    [ 109.934413] #0: (&(&nvmeq->q_lock)->rlock){-.....}, at: [] nvme_irq+0x1b/0x50 [nvme]
    [ 109.944010]
    [ 109.944010] stack backtrace:
    [ 109.948389] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G E 4.5.0+ #180
    [ 109.955734] Hardware name: Dell Inc. OptiPlex 7010/0YXT71, BIOS A15 08/12/2013
    [ 109.962989] 0000000000000000 ffff88011e203c38 ffffffff81383d9c ffffffff81c13540
    [ 109.970478] ffffffff826711d0 ffff88011e203ce8 ffffffff810bb429 0000000000000046
    [ 109.977964] 0000000000000046 0000000000000000 0000000000b2e597 ffffffff81f4cb00
    [ 109.985453] Call Trace:
    [ 109.987911] [] dump_stack+0x85/0xc9
    [ 109.993711] [] __lock_acquire+0x19b9/0x1c60
    [ 109.999575] [] ? trace_hardirqs_off+0xd/0x10
    [ 110.005524] [] ? complete+0x3d/0x50
    [ 110.010688] [] lock_acquire+0x90/0xf0
    [ 110.016029] [] ? nvme_del_cq_end+0x26/0x70 [nvme]
    [ 110.022418] [] _raw_spin_lock_irqsave+0x4b/0x60
    [ 110.028632] [] ? nvme_del_cq_end+0x26/0x70 [nvme]
    [ 110.035019] [] nvme_del_cq_end+0x26/0x70 [nvme]
    [ 110.041232] [] blk_mq_end_request+0x35/0x60
    [ 110.047095] [] nvme_complete_rq+0x68/0x190 [nvme]
    [ 110.053481] [] __blk_mq_complete_request+0x8f/0x130
    [ 110.060043] [] blk_mq_complete_request+0x31/0x40
    [ 110.066343] [] __nvme_process_cq+0x83/0x240 [nvme]
    [ 110.072818] [] nvme_irq+0x25/0x50 [nvme]
    [ 110.078419] [] handle_irq_event_percpu+0x36/0x110
    [ 110.084804] [] handle_irq_event+0x37/0x60
    [ 110.090491] [] handle_edge_irq+0x93/0x150
    [ 110.096180] [] handle_irq+0xa6/0x130
    [ 110.101431] [] do_IRQ+0x5e/0x120
    [ 110.106333] [] common_interrupt+0x8c/0x8c

    Reviewed-by: Johannes Thumshirn
    Signed-off-by: Ming Lin
    Reviewed-by: Christoph Hellwig
    Reviewed-by: Sagi Grimberg
    Signed-off-by: Jens Axboe

    Ming Lin
     
  • Multiple users have reported device initialization failure due the driver
    not receiving legacy PCI interrupts. This is not unique to any particular
    controller, but has been observed on multiple platforms.

    There have been no issues reported or observed when with message signaled
    interrupts, so this patch attempts to use MSI-x during initialization,
    falling back to MSI. If that fails, legacy would become the default.

    The setup_io_queues error handling had to change as a result: the admin
    queue's msix_entry used to be initialized to the legacy IRQ. The case
    where nr_io_queues is 0 would fail request_irq when setting up the admin
    queue's interrupt since re-enabling MSI-x fails with 0 vectors, leaving
    the admin queue's msix_entry invalid. Instead, return success immediately.

    Reported-by: Tim Muhlemmer
    Reported-by: Jon Derrick
    Signed-off-by: Keith Busch
    Signed-off-by: Jens Axboe

    Keith Busch
     
  • Its useful to iterate on all the active tags in cases
    where we will need to fail all the queues IO.

    Signed-off-by: Sagi Grimberg
    [hch: carefully check for valid tagsets]
    Reviewed-by: Christoph Hellwig
    Reviewed-by: Johannes Thumshirn
    Signed-off-by: Jens Axboe

    Sagi Grimberg
     
  • We could kmalloc() the payload, so need the offset in page.

    Signed-off-by: Ming Lin
    Reviewed-by: Christoph Hellwig
    Signed-off-by: Jens Axboe

    Ming Lin
     
  • Commit 947e9762a8dd ("writeback: update wb_over_bg_thresh() to use
    wb_domain aware operations") unintentionally changed this function's
    meaning from "are there more dirty pages than the background writeback
    threshold" to "are there more dirty pages than the writeback threshold".
    The background writeback threshold is typically half of the writeback
    threshold, so this had the effect of raising the number of dirty pages
    required to cause a writeback worker to perform background writeout.

    This can cause a very severe performance regression when a BDI uses
    BDI_CAP_STRICTLIMIT because balance_dirty_pages() and the writeback worker
    can now disagree on whether writeback should be initiated.

    For example, in a system having 1GB of RAM, a single spinning disk, and
    a "pass-through" FUSE filesystem mounted over the disk, application code
    mmapped a 128MB file on the disk and was randomly dirtying pages in that
    mapping.

    Because FUSE uses strictlimit and has a default max_ratio of only 1%,
    in balance_dirty_pages, thresh is ~200, bg_thresh is ~100, and the
    dirty_freerun_ceiling is the average of those, ~150. So, it pauses the
    dirtying processes when we have 151 dirty pages and wakes up a
    background writeback worker. But the worker tests the wrong threshold
    (200 instead of 100), so it does not initiate writeback and just
    returns.

    Thus, balance_dirty_pages keeps looping, sleeping and then waking up the
    worker who will do nothing. It remains stuck in this state until the few
    dirty pages that we have finally expire and we write them back for that
    reason. Then the whole process repeats, resulting in near-zero
    throughput through the FUSE BDI.

    The fix is to call the parameterized variant of wb_calc_thresh, so that
    the worker will do writeback if the bg_thresh is exceeded which was the
    bahavior before the referenced commit.

    Fixes: 947e9762a8dd ("writeback: update wb_over_bg_thresh() to use
    wb_domain aware operations")
    Signed-off-by: Howard Cochran
    Acked-by: Tejun Heo
    Signed-off-by: Jens Axboe

    Howard Cochran
     

11 Apr, 2016

4 commits

  • Linus Torvalds
     
  • Pull ARM fixes from Russell King:
    "A couple of small fixes, and wiring up the new syscalls which appeared
    during the merge window"

    * 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
    ARM: 8550/1: protect idiv patching against undefined gcc behavior
    ARM: wire up preadv2 and pwritev2 syscalls
    ARM: SMP enable of cache maintanence broadcast

    Linus Torvalds
     
  • Pull MMC fixes from Ulf Hansson:
    "Here are a couple of mmc fixes intended for v4.6 rc3:

    MMC host:
    - sdhci: Fix regression setting power on Trats2 board
    - sdhci-pci: Add support and PCI IDs for more Broxton host controllers"

    * tag 'mmc-v4.6-rc1' of git://git.linaro.org/people/ulf.hansson/mmc:
    mmc: sdhci-pci: Add support and PCI IDs for more Broxton host controllers
    mmc: sdhci: Fix regression setting power on Trats2 board

    Linus Torvalds
     
  • Pull i2c fixes from Wolfram Sang:
    "Some bugfixes from I2C:

    - fix a uevent triggered boot problem by removing a useless debug
    print

    - fix sysfs-attributes of the new i2c-demux-pinctrl driver to follow
    standard kernel behaviour

    - fix a potential division-by-zero error (needed two takes)"

    * 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
    i2c: jz4780: really prevent potential division by zero
    Revert "i2c: jz4780: prevent potential division by zero"
    i2c: jz4780: prevent potential division by zero
    i2c: mux: demux-pinctrl: Update docs to new sysfs-attributes
    i2c: mux: demux-pinctrl: Clean up sysfs attributes
    i2c: prevent endless uevent loop with CONFIG_I2C_DEBUG_CORE

    Linus Torvalds