reliable way to set a kernel thread priority

From: ask (ask8y_at_yahoo.com)
Date: 09/23/05

  • Next message: Sagaert Johan: "makefile question / problem" 
    Date: 23 Sep 2005 14:25:16 -0700

    I have researched for this for a while but not found a good answer for
    it. Basic I create a kernel thread and I want set priority for it.

    Some example I browse through is to change the current->rt_priority or
    current->prio, directly. I found that is probably not righ, I saw
    kernel crashes.

    I look one example in kernel exmaple, function defined in sched.c

    migration_thread(). This thread calls setscheduler() to set the
    priority. In fact a bad idea, as setscheduler() itself calls
    copy_from_user(), which expect some memory from user space.
    migration_thread() does not even check the return of setscheduler() ,
    so it does not really set the priority.

    I cam mimic the implementation of setscheduler() but take out
    copy_from_user(), it's really a pain in....

    Why there is no such utility in the kernel? Point it to if you know
    any. Also how migration_thread() is supposed to work in the kernel?

  • Next message: Sagaert Johan: "makefile question / problem"

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