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Now uses thread_yield() instead of snooze(5), patch by Danny Robson.

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git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@16589 a95241bf-73f2-0310-859d-f6bbb57e9c96
This commit is contained in:
Axel Dörfler 2006-03-05 20:06:44 +00:00
parent 9e3f619722
commit ecc6684dca
1 changed files with 7 additions and 9 deletions
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16
src/add-ons/kernel/drivers/random/driver.c
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@ -4,19 +4,21 @@
*/
/* Made into a BeOS /dev/random and /dev/urandom by Daniel Berlin */
/* Adapted for Haiku by David Reid, Axel Doerfler */
/* Adapted for Haiku by David Reid, Axel Dörfler */
#include <OS.h>
#include <Drivers.h>
#include <kernel/thread.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#define TRACE_DRIVER 0
#if TRACE_DRIVER
//#define TRACE_DRIVER
#ifdef TRACE_DRIVER
# define TRACE(x) dprintf x
#else
# define TRACE(x) ;
@ -169,7 +171,7 @@ chseed(ch_randgen *prandgen, const uint64 seed)
/** The heart of Yarrow 2000 Chuma Random Number Generator: fast and reliable
* randomness collection.
* Thread yielding function is the most OPTIMAL source of randomness combined
* with a clock counter (editor's note: thread_yield() is not properly done in BeOS).
* with a clock counter.
* It doesn't have to switch to another thread, the call itself is random enough.
* Test it yourself.
* This FASTEST way to collect minimal randomness on each step couldn't use the
@ -189,11 +191,7 @@ reseed(ch_randgen *prandgen, const uint32 initTimes)
for (j = initTimes; j; j--) {
for (i = NK * initTimes; i; i--) {
// Note: there is no yield() in BeOS - we use snooze as an approximation,
// although it might not work as good as this one (especially, it's not
// as cheap as).
//thread_yield();
snooze(5);
thread_yield();
y.Q[0] += system_time();
attach(&x, &y, 0x52437EFFU, 0x026A4CEBU, 0xD9E66AC9U, 0x56E5A975U);