On Tue, Jun 20, 2006 at 10:48:07AM -0400, Lennart Sorensen wrote: > On Tue, Jun 20, 2006 at 08:53:55AM -0500, Jon Mason wrote: > > The amount of polls per received packet is very low, thus removing the > > benefit of NAPI. A compile time option would allow those users who know > > better to DTRT. > > Well I know on the slow poke system I run on, with the napi polling, the > system can process packets, and get work done, and not fall over and die > from handling interrupts. Without it, even 70Mbit of data on a single > port will flood the system with packet overruns to the point the > watchdog times out and the system reboots. So I don't know if polling > is slightly more inefficient with little traffic, it is certainly a lot > more efficient and safer when there is suddenly a lot more traffic. > Maybe it should be a module option, so that you can pick what you want. > Heck it could be a per port option even. :)
The point of my comment was CPU utilization. It appears that a bug is trying to be fixed by adding NAPI. This sounds a bit hackish to me, and could hide the root cause of the problem. So I'm not sure that is the best idea, but I will defer to the maintainer. > > > Yup, but the "everyone else is doing it" argument never worked with my > > parents. All it takes is one brave soul to determine the reasoning > > behind the magic numbers and convert them into #define's. Shouldn't be > > more than one day's work. > > Is this a magic number in your opinion? > > lp->a.write_csr(ioaddr, 0, 0x0002); /* Set STRT bit */ > > I guess one could do > #define CSR0_RST 0x0001 > #define CSR0_STRT 0x0002 > #define CSR0_STOP 0x0004 > etc... > > and then > lp->a.write_csr(ioaddr, 0, CSR0_STRT); /* Set STRT bit */ > > Does that help? I am not sure. I think the comment behind it is > plenty. But your example is just one instance. Here is one without a comment: lp->a.write_csr(ioaddr, 4, 0x0915); What is it doing? Is it still needed? Can it be done anywhere else? Who knows, because it is magic. The 4 can be defined as CSR0_STOP, per your example above, but what does value 0x0915 do? My point was that there are certain parts of the code which are non-intuative and should be commented and there are others which a good descrptive value would be nice. > > Len Sorensen - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
