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freebsd-skq/sys/libkern
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Conrad Meyer 8a0edc914f Add prng(9) API 
Add prng(9) as a replacement for random(9) in the kernel.

There are two major differences from random(9) and random(3):

- General prng(9) APIs (prng32(9), etc) do not guarantee an
  implementation or particular sequence; they should not be used for
  repeatable simulations.

- However, specific named API families are also exposed (for now: PCG),
  and those are expected to be repeatable (when so-guaranteed by the named
  algorithm).

Some minor differences from random(3) and earlier random(9):

- PRNG state for the general prng(9) APIs is per-CPU; this eliminates
  contention on PRNG state in SMP workloads.  Each PCPU generator in an
  SMP system produces a unique sequence.

- Better statistical properties than the Park-Miller ("minstd") PRNG
  (longer period, uniform distribution in all bits, passes
  BigCrush/PractRand analysis).

- Faster than Park-Miller ("minstd") PRNG -- no division is required to
  step PCG-family PRNGs.

For now, random(9) becomes a thin shim around prng32().  Eventually I
would like to mechanically switch consumers over to the explicit API.

Reviewed by:	kib, markj (previous version both)
Discussed with:	markm
Differential Revision:	https://reviews.freebsd.org/D25916
2020-08-13 20:48:14 +00:00
..
arm sys/kern: adoption of SPDX licensing ID tags. 2017-11-27 15:20:12 +00:00
arm64 arm64: add ".arch armv8-a+crc" to allow use of crc instructions 2017-06-08 20:06:09 +00:00
x86 Separate kernel crc32() implementation to its own header (gsb_crc32.h) and 2019-06-17 19:49:08 +00:00
arc4random_uniform.c libkern: Add arc4random_uniform 2020-05-23 17:51:06 +00:00
arc4random.c random(4): depessimize arc4random 2019-05-12 06:32:46 +00:00
ashldi3.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
ashrdi3.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
asprintf.c
bcd.c
bcmp.c Use __builtin for various mem* and b* (e.g. bzero) routines. 2018-06-02 18:03:35 +00:00
bcopy.c Simplify things a little 2018-05-10 02:31:48 +00:00
bsearch.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
cmpdi2.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
divdi3.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
explicit_bzero.c
ffs.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
ffsl.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
ffsll.c
fls.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
flsl.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
flsll.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
fnmatch.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
gsb_crc32.c Rename the macros to extract a single arm64 ID field. 2019-10-30 10:06:57 +00:00
iconv_converter_if.m
iconv_ucs.c sys/kern: adoption of SPDX licensing ID tags. 2017-11-27 15:20:12 +00:00
iconv_xlat16.c sys/kern: adoption of SPDX licensing ID tags. 2017-11-27 15:20:12 +00:00
iconv_xlat.c sys/kern: adoption of SPDX licensing ID tags. 2017-11-27 15:20:12 +00:00
iconv.c Mark more nodes as CTLFLAG_MPSAFE or CTLFLAG_NEEDGIANT (17 of many) 2020-02-26 14:26:36 +00:00
inet_aton.c sys/kern: adoption of SPDX licensing ID tags. 2017-11-27 15:20:12 +00:00
inet_ntoa.c
inet_ntop.c
inet_pton.c Remove pre-FreeBSD 7.0 compatibility. 2019-07-19 18:38:47 +00:00
jenkins_hash.c
lshrdi3.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
mcount.c mcount: tidy up ANSIfication 2018-10-20 22:39:35 +00:00
memcchr.c sys/kern: adoption of SPDX licensing ID tags. 2017-11-27 15:20:12 +00:00
memchr.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
memcmp.c Use __builtin for various mem* and b* (e.g. bzero) routines. 2018-06-02 18:03:35 +00:00
memmem.c
memset.c Use __builtin for various mem* and b* (e.g. bzero) routines. 2018-06-02 18:03:35 +00:00
moddi3.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
murmur3_32.c
qdivrem.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
qsort_r.c
qsort.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
quad.h sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
random.c Add prng(9) API 2020-08-13 20:48:14 +00:00
scanc.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
strcasecmp.c spdx: initial adoption of licensing ID tags. 2017-11-18 14:26:50 +00:00
strcat.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
strchr.c str(r)chr: Replace union abuse with __DECONST 2018-06-04 18:47:14 +00:00
strchrnul.c libkern: Implement strchrnul(3) 2019-08-19 22:53:05 +00:00
strcmp.c Port the NetBSD KCSAN runtime to FreeBSD. 2019-11-21 11:22:08 +00:00
strcpy.c Port the NetBSD KCSAN runtime to FreeBSD. 2019-11-21 11:22:08 +00:00
strcspn.c sys/kern: adoption of SPDX licensing ID tags. 2017-11-27 15:20:12 +00:00
strdup.c Add non-sleepable strdup variant strdup_flags 2019-02-20 20:48:10 +00:00
strlcat.c sys/kern: adoption of SPDX licensing ID tags. 2017-11-27 15:20:12 +00:00
strlcpy.c Sync strlcpy with userland version, again 2018-06-21 17:35:13 +00:00
strlen.c Port the NetBSD KCSAN runtime to FreeBSD. 2019-11-21 11:22:08 +00:00
strncat.c libkern: use nul for terminating char rather than 0 2018-02-13 19:17:48 +00:00
strncmp.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
strncpy.c libkern: use nul for terminating char rather than 0 2018-02-13 19:17:48 +00:00
strndup.c
strnlen.c sys/kern: adoption of SPDX licensing ID tags. 2017-11-27 15:20:12 +00:00
strrchr.c str(r)chr: Replace union abuse with __DECONST 2018-06-04 18:47:14 +00:00
strsep.c libkern: use nul for terminating char rather than 0 2018-02-13 19:17:48 +00:00
strspn.c sys/kern: adoption of SPDX licensing ID tags. 2017-11-27 15:20:12 +00:00
strstr.c libkern: use nul for terminating char rather than 0 2018-02-13 19:17:48 +00:00
strtol.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
strtoq.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
strtoul.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
strtouq.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
strvalid.c sys/kern: adoption of SPDX licensing ID tags. 2017-11-27 15:20:12 +00:00
timingsafe_bcmp.c
ucmpdi2.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
udivdi3.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00
umoddi3.c sys: further adoption of SPDX licensing ID tags. 2017-11-20 19:43:44 +00:00