Le jeudi 20 mai 2010 à 23:10 -0700, David Miller a écrit : > From: Nick Piggin <npiggin@xxxxxxx> > Date: Fri, 21 May 2010 16:06:00 +1000 > > > Actually, I bet we have a lot of bugs there with loading integers and > > pointers atomically, where the code assumes the loaded value will not > > be reloaded by the compiler, because it is an easy thing to assume. > > Alexey Kuznetsov was aware of this problem 8+ years ago when we were > first adding fine-grained locking the the networking. > > > atomic_read_light could be useful though, for sure. > > I definitely think so. And every usage of it should have a big fat > comment right next to it explaining how it's usage is valid in that > spot :-) > - I really doubt a valid (and dully commented) usage of atomic_read_light() will bring anything, but added complexity to API. Generated code will be the same than atomic_read() in these cases, unless some real factorization can be done inside a loop. We still have some uneeded RMW atomic ops to remove, before even thinking to optimise reads ;) -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
