[PATCH] documentation: explain memory barriers

[Randy Dunlap <randy.dunlap@oracle.com>]

On Wed, 1 Oct 2008 22:54:04 -0700 Andrew Morton wrote:

> This sequence is repeated three or four times and should be pulled out
> into a well-commented function.  That comment should explain the logic
> behind the use of these barriers, please.

and on 2008-OCT-08 Ben Hutchings wrote:

> All memory barriers need a comment to explain why and what they're doing.


Should this be added to CodingStyle or some other file?




From: Randy Dunlap <randy.dunlap@oracle.com>

We want all uses of memory barriers to be explained in the source
code.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
---
 Documentation/SubmitChecklist |    3 +++
 1 file changed, 3 insertions(+)

--- lin2627-rc9-docs.orig/Documentation/SubmitChecklist
+++ lin2627-rc9-docs/Documentation/SubmitChecklist
@@ -85,3 +85,6 @@ kernel patches.
 23: Tested after it has been merged into the -mm patchset to make sure
     that it still works with all of the other queued patches and various
     changes in the VM, VFS, and other subsystems.
+
+24: All memory barriers {e.g., barrier(), rmb(), wmb()} need a comment in the
+    source code that explains the logic of what they are doing and why.