On 11/4/05, Oliver Korpilla <Oliver.Korpilla@xxxxxx> wrote: > I'm currently putting some of the > more performance-critical stuff into kernel space. I think putting code in the kernel would not make that much of a performance difference. One thing I can think of is that you wouldn't have context switch overhead of a system call, but then it isn't very reasonable to do things yourself that would otherwise be done cleanly with a syscall. Apart from that, probably the only reason to use kernel-space threads would be for things you *wouldn't* be able to do with system calls, but I don't think this is performance related. > I did just wonder: Is there anything resembling a Linux process/thread > or a VxWorks task in kernel space? Or this way round: Are there > schedulable entities with priority able to run a function I supply. I think what you're asking for is a kernel thread. You can start kernel threads which are schedulable, or you can use tasklets. Tasklets roughly speaking are code snippets that get regularly executed by a kernel thread whose purpose is to run them depending on their priority. But tasklets *aren't* schedulable by themselves and they don't have context. > It's important that there no such constraints like "only one per cpu" or > "one in the whole system". You may have multiple number of kthreads in a system. Bahadir -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
