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  1. 17 Sep, 2014 10 commits
  3. 14 Jul, 2014 8 commits
  5. 11 Jun, 2014 5 commits
  7. 25 Apr, 2014 3 commits
  9. 24 Apr, 2014 3 commits
    • Alessandro Rubini's avatar
      zio_trigger_abort_disable() may sleep, waiting for CSET_HW_BUSY · bd476cb4
      Alessandro Rubini authored 
      Previously, the enable/disable sysfs store had to complete atomically,
as zio takes a spinlock to serialize the various concurrent enable and
disable that may happen.

Unfortunately, this is a problem when the hardware is keeping data
structures busy, and commit b77ca7f0 is not enough to solve the
problem: That commit uses udelay(10) in a loop, but in one
installation of ours the hardware operation runs in a work queue,
whereas the driving application has real-time priority.  So we really
need to schedule (or change the priorities, which is denied to us).
But we cannot schedule while holding a spinlock.

This patch, thus, make the following changes:

* zio_trigger_abort_disable() is renamed to __zio_trigger_abort_disable()
and does not sleep, but it returns -EAGAIN if HW_BUSY.

* a new zio_trigger_abort_disable() is offered, that retries while
scheduling.  This covers all sysfs users, but one, so this keeps the
patch smaller than I initially wrote it.

* __zobj_enable() return int, not void: 0 or -EAGAIN (without
sleeping, as it calls the new __zio_trigger_abort_disable()). It's an
internal function in ./sysfs.c, so this is not a problem.

* zobj_store_enable() accepts -AGAIN, and loops over if so.

This is more difficult than expected (I loved b77ca7f0), but I see no
easier solution to the weird RT priorities our users deploy.
Signed-off-by: Alessandro Rubini's avatarAlessandro Rubini <rubini@gnudd.com>
Acked-by: 's avatarFederico Vaga <federico.vaga@gmail.com>
      bd476cb4
    • Alessandro Rubini's avatar
      cset: rename BUSY to HW_BUSY · 1298bc57
      Alessandro Rubini authored 
      This flag has one user no more, but I already found the name
confusing while working on that only user -- a driver.

So this renames the flag, to make clear to readers (and myself) that
only hardware can set and clear the flag, obviously under cset lock.
Signed-off-by: Alessandro Rubini's avatarAlessandro Rubini <rubini@gnudd.com>
Acked-by: 's avatarFederico Vaga <federico.vaga@gmail.com>
      1298bc57
    • Federico Vaga's avatar
      bus: use bus_groups instead of bus_attrs on kernel > 3.11 · faf2a79c
      Federico Vaga authored 
      The Linux kernel patch b4e46138f946442608647be58e78e3ad4d15534e
removes bus_type.bus_attrs
Signed-off-by: Federico Vaga's avatarFederico Vaga <federico.vaga@cern.ch>
Acked-by: Alessandro Rubini's avatarAlessandro Rubini <rubini@gnudd.com>
      faf2a79c
  11. 02 Apr, 2014 1 commit
  13. 07 Mar, 2014 4 commits
  15. 04 Mar, 2014 1 commit
  17. 26 Feb, 2014 3 commits
  19. 24 Feb, 2014 2 commits