Re: mmap/munmap semantics

[Jamie Lokier <lk@tantalophile.demon.co.uk>]

Richard Guenther wrote:
> Oops, so I misread the code in drivers/char/mem.c ... well, so how can I
> get the same effect as for the private mapping? Not at the moment, I
> think? So memset should be faster than reading from /dev/zero?

Try them both.  /dev/zero may be faster eventually, once kiobufs do
clever things.  For the moment they should be about the same speed apart
from syscall entry cost, so zeroing a large region would be fine with
/dev/zero, and for a small region even when kiobufs are working, you
probably don't want the overhead of messing with page tables for a small
region.

enjoy,
-- Jamie
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