commit b34bd06e485abf5b24fc13a9a988ebf4d2915dd6
author Paul E. McKenney <paulmck@linux.vnet.ibm.com> Tue Jul 31 00:38:48 2007 -0700
committer Linus Torvalds <torvalds@woody.linux-foundation.org> Tue Jul 31 15:39:40 2007 -0700
tree 51121142a8c6194def341ab7a647bbd293790111
parent 7be77e20d59fc3dd3fdde31641e0bc821114d26b

bpqether: fix rcu usage

The rcu_dereference() primitive needs to be applied to an l-value in order to
ensure that compiler writers don't get an opportunity to apply reordering
optimizations that could result in multiple fetches or in other misbehavior.
This patch pulls the rcu_dereference() calls in bpq_seq_next() up to the point
at which the fetched pointers are still l-values, rather than after
list_entry() has transformed them into r-values.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>