CVS commit: src/sys/external/bsd/drm2/include/linux

["Taylor R Campbell" <riastradh%netbsd.org@localhost>]

Module Name:    src
Committed By:   riastradh
Date:           Sun Dec 19 01:18:02 UTC 2021

Modified Files:
        src/sys/external/bsd/drm2/include/linux: rcupdate.h

Log Message:
RCU pointer fixes.

- Use __typeof__, not typeof.
- Use membar_exit, not membar_producer.
  => We want a store-release, not store/store barrier.
  => Consider:
       foo->x = 42;
       assert(foo->x == 42);
       rcu_assign_pointer(globalfoo, foo);
     The foo->x load can be reordered past the store/store barrier
     (membar_producer), and happen after another thread has clobbered
     foo->x.
- Put the evaluation of the right-hand side before the barrier.


To generate a diff of this commit:
cvs rdiff -u -r1.8 -r1.9 src/sys/external/bsd/drm2/include/linux/rcupdate.h

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.