Re: [Question] arch-independent way to differentiate between user and kernel

From: Steven Rostedt (rostedt_at_goodmis.org)
Date: 08/03/05

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    To: Ingo Molnar <mingo@elte.hu>
Date:	Wed, 03 Aug 2005 08:18:48 -0400

    On Wed, 2005-08-03 at 12:48 +0200, Ingo Molnar wrote:
    >
    > i dont think there's any. user_mode(regs) gets the closest - it might
    > make sense to generalize it over all arches.
    >
    > update_process_times() gets an arch-independent 'was the tick user-space
    > or kernel-space' flag, so the best starting point would be to look at
    > the output of:
    >
    > for N in `find . -name '*.c' | xargs grep update_process_times |
    > grep arch`; do echo $N; done | grep update_process_times |
    > sort | uniq -c
    >
    > which gives:
    >
    > 2 update_process_times()
    > 1 update_process_times(CHOOSE_MODE(user_context(UPT_SP(regs)),
    > 6 update_process_times(user);
    > 1 update_process_times(user_mode(fp));
    > 33 update_process_times(user_mode(regs));
    > 2 update_process_times(user_mode_vm(regs));
    >
    > so ~33 calls use user_mode(regs), and the rest needs to be reviewed and
    > possibly changed. Looks doable.

    Ingo,

    Thanks for the starting point. For now I'll submit a patch that doesn't
    do the user_mode checks as discussed before. Then if I can find
    something here, I'll send another patch on top of the first patch later.

    -- Steve

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