linux.git/kernel/rcu, branch v3.19

Merge branches 'torture.2014.11.03a', 'cpu.2014.11.03a', 'doc.2014.11.13a', 'fixes.2014.11.13a', 'signal.2014.10.29a' and 'rt.2014.10.29a' into HEAD

2014-11-13T18:39:04+00:00

cpu.2014.11.03a: Changes for per-CPU variables.
doc.2014.11.13a: Documentation updates.
fixes.2014.11.13a: Miscellaneous fixes.
signal.2014.10.29a: Signal changes.
rt.2014.10.29a: Real-time changes.
torture.2014.11.03a: torture-test changes.

rcu: Fix FIXME in rcu_tasks_kthread()

2014-11-13T18:35:41+00:00

This commit affines rcu_tasks_kthread() to the housekeeping CPUs
in CONFIG_NO_HZ_FULL builds.  This is just a default, so systems
administrators are free to put this kthread somewhere else if they wish.

Signed-off-by: Paul E. McKenney

rcutorture: Fix rcu_torture_cbflood() memory leak

2014-11-04T03:26:41+00:00

Commit 38706bc5a29a (rcutorture: Add callback-flood test) vmalloc()ed
a bunch of RCU callbacks, but failed to free them.  This commit fixes
that oversight.

Signed-off-by: Paul E. McKenney 
Reviewed-by: Pranith Kumar

rcutorture: Add early boot self tests

2014-11-04T03:26:37+00:00

Add early boot self tests for RCU under CONFIG_PROVE_RCU.

Currently the only test is adding a dummy callback which increments a counter
which we then later verify after calling rcu_barrier*().

Signed-off-by: Pranith Kumar 
Signed-off-by: Paul E. McKenney

rcu: Remove "cpu" argument to rcu_cleanup_after_idle()

2014-11-04T03:20:56+00:00

The "cpu" argument to rcu_cleanup_after_idle() is always the current
CPU, so drop it.  This moves the smp_processor_id() from the caller to
rcu_cleanup_after_idle(), saving argument-passing overhead.  Again,
the anticipated cross-CPU uses of these functions has been replaced
by NO_HZ_FULL.

Signed-off-by: Paul E. McKenney 
Reviewed-by: Pranith Kumar

rcu: Remove "cpu" argument to rcu_prepare_for_idle()

2014-11-04T03:20:49+00:00

The "cpu" argument to rcu_prepare_for_idle() is always the current
CPU, so drop it.  This in turn allows two of the uses of "cpu" in
this function to be replaced with a this_cpu_ptr() and the third by
smp_processor_id(), replacing that of the call to rcu_prepare_for_idle().
Again, the anticipated cross-CPU uses of these functions has been replaced
by NO_HZ_FULL.

Signed-off-by: Paul E. McKenney 
Reviewed-by: Pranith Kumar

rcu: Remove "cpu" argument to rcu_needs_cpu()

2014-11-04T03:20:43+00:00

The "cpu" argument to rcu_needs_cpu() is always the current CPU, so drop
it.  This in turn allows the "cpu" argument to rcu_cpu_has_callbacks()
to be removed, which allows the uses of "cpu" in both functions to be
replaced with a this_cpu_ptr().  Again, the anticipated cross-CPU uses
of these functions has been replaced by NO_HZ_FULL.

Signed-off-by: Paul E. McKenney 
Reviewed-by: Pranith Kumar

rcu: Remove "cpu" argument to rcu_note_context_switch()

2014-11-04T03:20:34+00:00

The "cpu" argument to rcu_note_context_switch() is always the current
CPU, so drop it.  This in turn allows the "cpu" argument to
rcu_preempt_note_context_switch() to be removed, which allows the sole
use of "cpu" in both functions to be replaced with a this_cpu_ptr().
Again, the anticipated cross-CPU uses of these functions has been
replaced by NO_HZ_FULL.

Signed-off-by: Paul E. McKenney 
Reviewed-by: Pranith Kumar

rcu: Remove "cpu" argument to rcu_preempt_check_callbacks()

2014-11-04T03:20:26+00:00

Because rcu_preempt_check_callbacks()'s argument is guaranteed to
always be the current CPU, drop the argument and replace per_cpu()
with __this_cpu_read().

Signed-off-by: Paul E. McKenney 
Reviewed-by: Pranith Kumar

rcu: Remove "cpu" argument to rcu_pending()

2014-11-04T03:20:18+00:00

Because rcu_pending()'s argument is guaranteed to always be the current
CPU, drop the argument and replace per_cpu_ptr() with this_cpu_ptr().

Signed-off-by: Paul E. McKenney 
Reviewed-by: Pranith Kumar