Messages in this thread | | | Date | Fri, 17 Aug 2007 12:50:33 -0600 | From | "Chris Friesen" <> | Subject | Re: [PATCH 0/24] make atomic_read() behave consistently across all architectures |
| |
Linus Torvalds wrote:
> - in other words, the *only* possible meaning for "volatile" is a purely > single-CPU meaning. And if you only have a single CPU involved in the > process, the "volatile" is by definition pointless (because even > without a volatile, the compiler is required to make the C code appear > consistent as far as a single CPU is concerned).
I assume you mean "except for IO-related code and 'random' values like jiffies" as you mention later on? I assume other values set in interrupt handlers would count as "random" from a volatility perspective?
> So anybody who argues for "volatile" fixing bugs is fundamentally > incorrect. It does NO SUCH THING. By arguing that, such people only show > that you have no idea what they are talking about.
What about reading values modified in interrupt handlers, as in your "random" case? Or is this a bug where the user of atomic_read() is invalidly expecting a read each time it is called?
Chris - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |