]> git.karo-electronics.de Git - linux-beck.git/commit
rcu: define __rcu address space modifier for sparse
authorPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Wed, 28 Apr 2010 21:39:09 +0000 (14:39 -0700)
committerPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Fri, 20 Aug 2010 00:17:59 +0000 (17:17 -0700)
commitca5ecddfa8fcbd948c95530e7e817cee9fb43a3d
tree0ad1c320c2e6612a9a230a58d8588850701c048c
parentd34a16661ed0fed433c9469d7cfa3ca4d30ca42e
rcu: define __rcu address space modifier for sparse

This commit provides definitions for the __rcu annotation defined earlier.
This annotation permits sparse to check for correct use of RCU-protected
pointers.  If a pointer that is annotated with __rcu is accessed
directly (as opposed to via rcu_dereference(), rcu_assign_pointer(),
or one of their variants), sparse can be made to complain.  To enable
such complaints, use the new default-disabled CONFIG_SPARSE_RCU_POINTER
kernel configuration option.  Please note that these sparse complaints are
intended to be a debugging aid, -not- a code-style-enforcement mechanism.

There are special rcu_dereference_protected() and rcu_access_pointer()
accessors for use when RCU read-side protection is not required, for
example, when no other CPU has access to the data structure in question
or while the current CPU hold the update-side lock.

This patch also updates a number of docbook comments that were showing
their age.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Christopher Li <sparse@chrisli.org>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
include/linux/compiler.h
include/linux/rcupdate.h
include/linux/srcu.h
kernel/rcupdate.c
lib/Kconfig.debug