On Mon, 3 Jan 2005, Alan Cox wrote: > On Llu, 2005-01-03 at 18:31, Pete Zaitcev wrote: > > Fist is SMP: volatile does nothing to help serialize accesses, although > > I can see that in perhaps in this case it's not an issue. The second > > is portability: on a few CPUs special instructions are necessary for > > serializations, which are provided by memory barriers. I would suggest > > adding barriers explicitly. > > It also causes abominably bad code generation compared to explicit > barriers. Consider volatile the wrong solution.
Alan, I respect your judgement and your advice. If after looking more closely at this you still think the code should be changed to use barriers instead, I will do it. But first you should read my reply to Pete, and you should see how the driver is affected. You will be hard-pressed to find any spots where the "volatile" causes abominable code generation. Alan Stern ------------------------------------------------------- The SF.Net email is sponsored by: Beat the post-holiday blues Get a FREE limited edition SourceForge.net t-shirt from ThinkGeek. It's fun and FREE -- well, almost....http://www.thinkgeek.com/sfshirt _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
