Re: [question/comment/help] pseudo function-call from kernel to a
Marcel Lanz (email@example.com)
Wed, 10 Nov 1999 12:05:13 +0100
"Richard B. Johnson" wrote:
> Instead, if you are copying something that can change, so you need a
> spin-lock, do:
> spin_lock_irqsave(&lock_flag, flags);
> memcpy(tmp_buf, volatile_buf, len);
> spin_unlock(&lock_flag, flags);
> copy_to_user(user_buf, tmp_buf, len);
> Stuff that can't possibly change during the operation, requires no
> spin-locks at all. In your code snippet retained above, everything is
> a constant. It needs no lock.
thank you very much. I didn't saw that. I am new on kernel-programming.
Now I see
that it is all task-local, so I haven't to protect anything.
Marcel Lanz <firstname.lastname@example.org>
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