On Wed, Jun 23, 2010 at 09:28:57AM -0700, Luis R. Rodriguez wrote: > On Wed, Jun 23, 2010 at 7:39 AM, Johannes Stezenbach <js@xxxxxxxxx> wrote: > > > > If enabling ASPM comes with a performance penalty (which is not unexpected, > > there is usually a tradeoff between performance and power consumption), > > do you think a boot time option (pcie_aspm=) or compile time option > > (CONFIG_PCIEASPM) is the right user interface? > > > > > > But meanwhile I found that CONFIG_PCIEASPM has a runtime > > interface, /sys/module/pcie_aspm/parameters/policy. > > http://lwn.net/Articles/266585/ > > Same thing, its to be used by developers not users, damn it we should > just remove this crap. Hopefully I got at least the message across that there is a good reason to have an interface where the user can select the ASPM policy? If your answer is "reboot and change the BIOS setting" then you didn't get what I was talking about _at all_. Also, having now briefly looked at pcie/aspm.c, I do not share your opinion that it is crap, except maybe for the force enable. If I read it correctly it will by default keep the BIOS settings, but offers a per-device sysfs attribute to change the ASPM link state, and it seems to do sanity checking, and takes care that both ends of the link agree. (disclaimer: I haven't tested any of it, only briefly looked at the code) Johannes -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
