random PIDs

[Heusden, Folkert van]

Finished & tested my random PID kernel/fork.c:get_pid() replacement.
This one keeps track of the last N (default is 64) pids who have exited.
These are then not used. So, one cannot have more then 32767 - (64 + 1
(init) + 1 (idle)) = 32761 processes :o)

I know that it was all implemented before, but this patch is very small 
and I couldn't stand the idea the fact that my last announcement was for
a patch which didn't work at all :o)

One can find it at: http://www.vanheusden.com/Linux/kernel_patches.php3
(or: http://www.vanheusden.com/Linux/fp-2.2.19.patch.gz but then you
miss the list of other patches ;-])
Patch is against kernel 2.2.19.

I did not do any performance tests, but the machine I tested it on
(300MHz dec alpha) felt (felt?) as smooth as before :o)

Folkert van Heusden

[ www.vanheusden.com ]

p.s. the patch mentioned above also raises the number of pool-words
from 128 to 2048, adds code to do_exit which tells you if the idle
task is killed (as in 2.4.x), and replaces
net/core/utils.c:net_[s]random() with something which uses
get_random_bytes().