On 10/05/2016 03:49 PM, Ming Lei wrote:

We can use srcu read lock for BLOCKING and rcu read lock for non-BLOCKING,
by putting *_read_lock() and *_read_unlock() into two wrappers, which
should minimize the cost of srcu read lock & unlock and the code is still easy
to read & verify.

Hello Ming,

The lock checking algorithms in the sparse and smatch static checkers 
are unable to deal with code of the type "if (condition) (un)lock()". So 
unless someone has a better proposal my preference is to use the 
approach from the patch at the start of this e-mail thread.

Thanks,

Bart.