cond_resched.2017.12.04a: Convert cond_resched_rcu_qs() to cond_resched()
dyntick.2017.11.28a: Make RCU dynticks handle interrupts from NMI
fixes.2017.12.11a: Miscellaneous fixes
srbd.2017.12.05a: Remove now-redundant smp_read_barrier_depends()
torture.2017.12.11a: Torture-testing update

Now that READ_ONCE() implies smp_read_barrier_depends(), the commit
updates now-misleading comments to account for this change.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

If cond_resched() returns false, then it has already invoked
rcu_all_qs().  This is also invoked (now redundantly) by
rcu_note_voluntary_context_switch().  This commit therefore changes
cond_resched_rcu_qs() to invoke rcu_note_voluntary_context_switch_lite()
instead of rcu_note_voluntary_context_switch() to avoid the redundant
invocation of rcu_all_qs().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

READ_ONCE() now has an implicit smp_read_barrier_depends() call, so it
can be used instead of lockless_dereference() without any change in
semantics.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1508840570-22169-4-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Because many of RCU's files have not been included into docbook, a
number of errors have accumulated.  This commit fixes them.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull SCSI updates from James Bottomley:
 "This is mostly updates of the usual suspects: lpfc, qla2xxx, hisi_sas,
  megaraid_sas, zfcp and a host of minor updates.

  The major driver change here is the elimination of the block based
  cciss driver in favour of the SCSI based hpsa driver (which now drives
  all the legacy cases cciss used to be required for). Plus a reset
  handler clean up and the redo of the SAS SMP handler to use bsg lib"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (279 commits)
  scsi: scsi-mq: Always unprepare before requeuing a request
  scsi: Show .retries and .jiffies_at_alloc in debugfs
  scsi: Improve requeuing behavior
  scsi: Call scsi_initialize_rq() for filesystem requests
  scsi: qla2xxx: Reset the logo flag, after target re-login.
  scsi: qla2xxx: Fix slow mem alloc behind lock
  scsi: qla2xxx: Clear fc4f_nvme flag
  scsi: qla2xxx: add missing includes for qla_isr
  scsi: qla2xxx: Fix an integer overflow in sysfs code
  scsi: aacraid: report -ENOMEM to upper layer from aac_convert_sgraw2()
  scsi: aacraid: get rid of one level of indentation
  scsi: aacraid: fix indentation errors
  scsi: storvsc: fix memory leak on ring buffer busy
  scsi: scsi_transport_sas: switch to bsg-lib for SMP passthrough
  scsi: smartpqi: remove the smp_handler stub
  scsi: hpsa: remove the smp_handler stub
  scsi: bsg-lib: pass the release callback through bsg_setup_queue
  scsi: Rework handling of scsi_device.vpd_pg8[03]
  scsi: Rework the code for caching Vital Product Data (VPD)
  scsi: rcu: Introduce rcu_swap_protected()
  ...

A common pattern in RCU code is to assign a new value to an RCU pointer
after having read and stored the old value. Introduce a macro for this
pattern.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Shane M Seymour <shane.seymour@hpe.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

doc.2017.08.17a: Documentation updates.
fixes.2017.08.17a: RCU fixes.
hotplug.2017.07.25b: CPU-hotplug updates.
misc.2017.08.17a: Miscellaneous fixes outside of RCU (give or take conflicts).
spin_unlock_wait_no.2017.08.17a: Remove spin_unlock_wait().
srcu.2017.07.27c: SRCU updates.
torture.2017.07.24c: Torture-test updates.

Currently, the exit-time support for TASKS_RCU is open-coded in do_exit().
This commit creates exit_tasks_rcu_start() and exit_tasks_rcu_finish()
APIs for do_exit() use.  This has the benefit of confining the use of the
tasks_rcu_exit_srcu variable to one file, allowing it to become static.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

The actual use of TASKS_RCU is only when PREEMPT, otherwise RCU-sched
is used instead.  This commit therefore makes synchronize_rcu_tasks()
and call_rcu_tasks() available always, but mapped to synchronize_sched()
and call_rcu_sched(), respectively, when !PREEMPT.  This approach also
allows some #ifdefs to be removed from rcutorture.

Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Ingo Molnar <mingo@kernel.org>