On Thursday 09 October 2008 20:58, Ben Hutchings wrote:
No, I don't think so. We should absolutely force "all". That allows nobody
to be lazy, no confusion, and reminds people that memory barriers are not
easy to follow for a new reader of the code, or necessarily even the author,
6 months later. If somebody is too lazy to write a comment, they can use
locks
One last quick quiz, easier than the earlier ones...
mm/vmscan.c:__remove_mapping has a score of lines documenting exactly
what memory operations are being ordered, and even an example of what
happens if the ordering is not folllowed. This is a pretty good comment,
if I say so myself. However, it has one deficiency in that it doesn't
explicitly state where the write barrier(s) is (IMO the comments for one
part of an ordering protocol should reference the other parts of the
protcol).
Where are the store barriers, or why are they not required?
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