On Tue, 17 Feb 2004, Tim Roberts wrote: > Pier Paolo Glave wrote:
> >I'm trying to optimize an embedded system based on > >ARM9 CPU, which is running a cross-compiled version of > >XFree86 4.3.0 on linux 2.4.18. > >I noticed that XFree86, at start-up, makes a complete > >scan of 256 possible PCI buses, looking for devices, > >without checking (e.g. from /proc/bus/pci) how many > >buses are actually present on the system. > >I thought that in my system, where I have one bus > >only, this could lead to a high startup time, so I > >tried to make a patch (reported below) that detects > >the actual number of buses by parsing > >/proc/bus/pci/devices. > >The results were not amazing, because the saved time > >is really little. > Right. The gain is very, very small, and it comes at the cost of an > additional dependency on the presence and exact format of > /proc/bus/pci/devices. /proc/bus was not introduced until the 2.2 > kernels, so your change would prevent XFree86 from running on 2.0.x > kernels. I don't know whether there are other issue with 2.0.x kernels > or not, but since the cost of a full PCI bus search is so small, it > seems counterproductive to make this change. This comment is incorrect given that the code Pier modifies isn't even traversed with a 2.0 (or earlier) kernel. However, I'd defer this change to a post-4.4 timeframe because it's not a bug fix. Marc. +----------------------------------+-----------------------------------+ | Marc Aurele La France | work: 1-780-492-9310 | | Computing and Network Services | fax: 1-780-492-1729 | | 352 General Services Building | email: [EMAIL PROTECTED] | | University of Alberta +-----------------------------------+ | Edmonton, Alberta | | | T6G 2H1 | Standard disclaimers apply | | CANADA | | +----------------------------------+-----------------------------------+ XFree86 developer and VP. ATI driver and X server internals. _______________________________________________ Devel mailing list [EMAIL PROTECTED] http://XFree86.Org/mailman/listinfo/devel
