1. 05 Jan, 2018 17 commits
  2. 22 Dec, 2017 1 commit
    • Jens Axboe's avatar
      blk-mq: improve heavily contended tag case · 4e5dff41
      Jens Axboe authored
      Even with a number of waitqueues, we can get into a situation where we
      are heavily contended on the waitqueue lock. I got a report on spc1
      where we're spending seconds doing this. Arguably the use case is nasty,
      I reproduce it with one device and 1000 threads banging on the device.
      But that doesn't mean we shouldn't be handling it better.
      
      What ends up happening is that a thread will fail to get a tag, add
      itself to the waitqueue, and subsequently get woken up when a tag is
      freed - only to find itself going back to sleep on the waitqueue.
      
      Instead of waking all threads, use an exclusive wait and wake up our
      sbitmap batch count instead. This seems to work well for me (massive
      improvement for this use case), and it survives basic testing. But I
      haven't fully verified it yet.
      
      An additional improvement is running the queue and checking for a new
      tag BEFORE needing to add ourselves to the waitqueue.
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      4e5dff41
  3. 18 Dec, 2017 1 commit
  4. 17 Dec, 2017 20 commits
  5. 16 Dec, 2017 1 commit
    • Linus Torvalds's avatar
      Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma · f3b5ad89
      Linus Torvalds authored
      Pull rdma fixes from Jason Gunthorpe:
       "More fixes from testing done on the rc kernel, including more SELinux
        testing. Looking forward, lockdep found regression today in ipoib
        which is still being fixed.
      
        Summary:
      
         - Fix for SELinux on the umad SMI path. Some old hardware does not
           fill the PKey properly exposing another bug in the newer SELinux
           code.
      
         - Check the input port as we can exceed array bounds from this user
           supplied value
      
         - Users are unable to use the hash field support as they want due to
           incorrect checks on the field restrictions, correct that so the
           feature works as intended
      
         - User triggerable oops in the NETLINK_RDMA handler
      
         - cxgb4 driver fix for a bad interaction with CQ flushing in iser
           caused by patches in this merge window, and bad CQ flushing during
           normal close.
      
         - Unbalanced memalloc_noio in ipoib in an error path"
      
      * tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
        IB/ipoib: Restore MM behavior in case of tx_ring allocation failure
        iw_cxgb4: only insert drain cqes if wq is flushed
        iw_cxgb4: only clear the ARMED bit if a notification is needed
        RDMA/netlink: Fix general protection fault
        IB/mlx4: Fix RSS hash fields restrictions
        IB/core: Don't enforce PKey security on SMI MADs
        IB/core: Bound check alternate path port number
      f3b5ad89