linux-toradex.git/kernel/rcupdate.c, branch v2.6.27.10

rcu: fix synchronize_rcu() so that kernel-doc works

2008-08-21T07:31:44+00:00

Fix RCU's synchronize_rcu() so that it looks like a C function, enabling
it to be recognized as a function with kernel-doc annotation.

Warning(linux-2.6.26-git11//kernel/rcupdate.c:81): No description found for parameter 'synchronize_rcu'
Warning(linux-2.6.26-git11//kernel/rcupdate.c:81): No description found for parameter 'call_rcu'

[akpm@linux-foundation.org: fix comment]
Signed-off-by: Randy Dunlap 
Signed-off-by: Andrew Morton 
Signed-off-by: Ingo Molnar

Merge branch 'generic-ipi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2008-07-15T21:12:03+00:00

* 'generic-ipi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (22 commits)
  generic-ipi: more merge fallout
  generic-ipi: merge fix
  x86, visws: use mach-default/entry_arch.h
  x86, visws: fix generic-ipi build
  generic-ipi: fixlet
  generic-ipi: fix s390 build bug
  generic-ipi: fix linux-next tree build failure
  fix: "smp_call_function: get rid of the unused nonatomic/retry argument"
  fix: "smp_call_function: get rid of the unused nonatomic/retry argument"
  fix "smp_call_function: get rid of the unused nonatomic/retry argument"
  on_each_cpu(): kill unused 'retry' parameter
  smp_call_function: get rid of the unused nonatomic/retry argument
  sh: convert to generic helpers for IPI function calls
  parisc: convert to generic helpers for IPI function calls
  mips: convert to generic helpers for IPI function calls
  m32r: convert to generic helpers for IPI function calls
  arm: convert to generic helpers for IPI function calls
  alpha: convert to generic helpers for IPI function calls
  ia64: convert to generic helpers for IPI function calls
  powerpc: convert to generic helpers for IPI function calls
  ...

Fix trivial conflicts due to rcu updates in kernel/rcupdate.c manually

on_each_cpu(): kill unused 'retry' parameter

2008-06-26T09:24:38+00:00

It's not even passed on to smp_call_function() anymore, since that
was removed. So kill it.

Acked-by: Jeremy Fitzhardinge 
Reviewed-by: Paul E. McKenney 
Signed-off-by: Jens Axboe

rcu: add rcu_barrier_sched() and rcu_barrier_bh()

2008-05-19T08:01:36+00:00

Add rcu_barrier_sched() and rcu_barrier_bh().  With these in place,
rcutorture no longer gives the occasional oops when repeatedly starting
and stopping torturing rcu_bh.  Also adds the API needed to flush out
pre-existing call_rcu_sched() callbacks.

Signed-off-by: Paul E. McKenney 
Signed-off-by: Mathieu Desnoyers 
Signed-off-by: Ingo Molnar 
Signed-off-by: Thomas Gleixner

rcu: add call_rcu_sched()

2008-05-19T08:01:36+00:00

Fourth cut of patch to provide the call_rcu_sched().  This is again to
synchronize_sched() as call_rcu() is to synchronize_rcu().

Should be fine for experimental and -rt use, but not ready for inclusion.
With some luck, I will be able to tell Andrew to come out of hiding on
the next round.

Passes multi-day rcutorture sessions with concurrent CPU hotplugging.

Fixes since the first version include a bug that could result in
indefinite blocking (spotted by Gautham Shenoy), better resiliency
against CPU-hotplug operations, and other minor fixes.

Fixes since the second version include reworking grace-period detection
to avoid deadlocks that could happen when running concurrently with
CPU hotplug, adding Mathieu's fix to avoid the softlockup messages,
as well as Mathieu's fix to allow use earlier in boot.

Fixes since the third version include a wrong-CPU bug spotted by
Andrew, getting rid of the obsolete synchronize_kernel API that somehow
snuck back in, merging spin_unlock() and local_irq_restore() in a
few places, commenting the code that checks for quiescent states based
on interrupting from user-mode execution or the idle loop, removing
some inline attributes, and some code-style changes.

Known/suspected shortcomings:

o	I still do not entirely trust the sleep/wakeup logic.  Next step
	will be to use a private snapshot of the CPU online mask in
	rcu_sched_grace_period() -- if the CPU wasn't there at the start
	of the grace period, we don't need to hear from it.  And the
	bit about accounting for changes in online CPUs inside of
	rcu_sched_grace_period() is ugly anyway.

o	It might be good for rcu_sched_grace_period() to invoke
	resched_cpu() when a given CPU wasn't responding quickly,
	but resched_cpu() is declared static...

This patch also fixes a long-standing bug in the earlier preemptable-RCU
implementation of synchronize_rcu() that could result in loss of
concurrent external changes to a task's CPU affinity mask.  I still cannot
remember who reported this...

Signed-off-by: Paul E. McKenney 
Signed-off-by: Mathieu Desnoyers 
Signed-off-by: Ingo Molnar 
Signed-off-by: Thomas Gleixner

rcupdate: fix comment

2008-02-14T00:21:18+00:00

This comment caused some consternation during fastcall removal.  Make it
truthful.

Signed-off-by: Paul E. McKenney 
Cc: Harvey Harrison 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Preempt-RCU: fix rcu_barrier for preemptive environment.

2008-01-25T20:08:24+00:00

Fix rcu_barrier() to work properly in preemptive kernel environment.
Also, the ordering of callback must be preserved while moving
callbacks to another CPU during CPU hotplug.

Signed-off-by: Gautham R Shenoy 
Signed-off-by: Dipankar Sarma 
Signed-off-by: Paul E. McKenney 
Reviewed-by: Steven Rostedt 
Signed-off-by: Ingo Molnar

Preempt-RCU: reorganize RCU code into rcuclassic.c and rcupdate.c

2008-01-25T20:08:24+00:00

This patch re-organizes the RCU code to enable multiple implementations
of RCU. Users of RCU continues to include rcupdate.h and the
RCU interfaces remain the same. This is in preparation for
subsequently merging the preemptible RCU implementation.

Signed-off-by: Gautham R Shenoy 
Signed-off-by: Dipankar Sarma 
Signed-off-by: Paul E. McKenney 
Reviewed-by: Steven Rostedt 
Signed-off-by: Ingo Molnar

Preempt-RCU: Use softirq instead of tasklets for

2008-01-25T20:08:23+00:00

This patch makes RCU use softirq instead of tasklets.

It also adds a memory barrier after raising the softirq
inorder to ensure that the cpu sees the most recently updated
value of rcu->cur while processing callbacks.
The discussion of the related theoretical race pointed out
by James Huang can be found here --> http://lkml.org/lkml/2007/11/20/603

Signed-off-by: Gautham R Shenoy 
Signed-off-by: Steven Rostedt 
Signed-off-by: Dipankar Sarma 
Reviewed-by: Steven Rostedt 
Signed-off-by: Ingo Molnar

rcu: fix section mismatch

2008-01-22T17:17:48+00:00

rcu_online_cpu() should be __cpuinit instead of __devinit.

WARNING: vmlinux.o(.text+0x4b6d5): Section mismatch: reference to .init.text: (between 'rcu_cpu_notify' and 'wakeme_after_rcu')

Signed-off-by: Randy Dunlap 
Cc: Sam Ravnborg 
Acked-by: Ingo Molnar 
Cc: Thomas Gleixner 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds