[ovs-dev] [PATCH] datapath: Remove backported random32().

Jesse Gross jesse at nicira.com
Fri Sep 17 20:00:31 UTC 2010


Nothing uses it anymore and it causes problems when backported on
some distributions.  Kernels we support have net_random(), which
is the same thing so there is no reason to have an entire copy of
the random number generator in our source tree.

Reported-by: Alexey I. Froloff <raorn at altlinux.org>
Signed-off-by: Jesse Gross <jesse at nicira.com>
---
 datapath/datapath.c                                |    1 -
 datapath/linux-2.6/Modules.mk                      |    2 -
 .../linux-2.6/compat-2.6/include/linux/random.h    |   17 ---
 datapath/linux-2.6/compat-2.6/random32.c           |  144 --------------------
 4 files changed, 0 insertions(+), 164 deletions(-)
 delete mode 100644 datapath/linux-2.6/compat-2.6/include/linux/random.h
 delete mode 100644 datapath/linux-2.6/compat-2.6/random32.c

diff --git a/datapath/datapath.c b/datapath/datapath.c
index fe37ec1..b3f77b3 100644
--- a/datapath/datapath.c
+++ b/datapath/datapath.c
@@ -29,7 +29,6 @@
 #include <linux/udp.h>
 #include <linux/version.h>
 #include <linux/ethtool.h>
-#include <linux/random.h>
 #include <linux/wait.h>
 #include <asm/system.h>
 #include <asm/div64.h>
diff --git a/datapath/linux-2.6/Modules.mk b/datapath/linux-2.6/Modules.mk
index 7f4cae6..5a0e9ad 100644
--- a/datapath/linux-2.6/Modules.mk
+++ b/datapath/linux-2.6/Modules.mk
@@ -4,7 +4,6 @@ openvswitch_sources += \
 	linux-2.6/compat-2.6/genetlink-openvswitch.c \
 	linux-2.6/compat-2.6/ip_output-openvswitch.c \
 	linux-2.6/compat-2.6/kmemdup.c \
-	linux-2.6/compat-2.6/random32.c \
 	linux-2.6/compat-2.6/skbuff-openvswitch.c \
 	linux-2.6/compat-2.6/time.c
 openvswitch_headers += \
@@ -32,7 +31,6 @@ openvswitch_headers += \
 	linux-2.6/compat-2.6/include/linux/netfilter_bridge.h \
 	linux-2.6/compat-2.6/include/linux/netfilter_ipv4.h \
 	linux-2.6/compat-2.6/include/linux/netlink.h \
-	linux-2.6/compat-2.6/include/linux/random.h \
 	linux-2.6/compat-2.6/include/linux/rculist.h \
 	linux-2.6/compat-2.6/include/linux/rtnetlink.h \
 	linux-2.6/compat-2.6/include/linux/skbuff.h \
diff --git a/datapath/linux-2.6/compat-2.6/include/linux/random.h b/datapath/linux-2.6/compat-2.6/include/linux/random.h
deleted file mode 100644
index 4e4932c..0000000
--- a/datapath/linux-2.6/compat-2.6/include/linux/random.h
+++ /dev/null
@@ -1,17 +0,0 @@
-#ifndef __LINUX_RANDOM_WRAPPER_H
-#define __LINUX_RANDOM_WRAPPER_H 1
-
-#include_next <linux/random.h>
-
-#include <linux/version.h>
-#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,19)
-
-#ifdef __KERNEL__
-u32 random32(void);
-void srandom32(u32 seed);
-#endif /* __KERNEL__ */
-
-#endif /* linux kernel < 2.6.19 */
-
-
-#endif
diff --git a/datapath/linux-2.6/compat-2.6/random32.c b/datapath/linux-2.6/compat-2.6/random32.c
deleted file mode 100644
index b0dd2a3..0000000
--- a/datapath/linux-2.6/compat-2.6/random32.c
+++ /dev/null
@@ -1,144 +0,0 @@
-#include <linux/version.h>
-#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,19)
-
-/*
-  This is a maximally equidistributed combined Tausworthe generator
-  based on code from GNU Scientific Library 1.5 (30 Jun 2004)
-
-   x_n = (s1_n ^ s2_n ^ s3_n)
-
-   s1_{n+1} = (((s1_n & 4294967294) <<12) ^ (((s1_n <<13) ^ s1_n) >>19))
-   s2_{n+1} = (((s2_n & 4294967288) << 4) ^ (((s2_n << 2) ^ s2_n) >>25))
-   s3_{n+1} = (((s3_n & 4294967280) <<17) ^ (((s3_n << 3) ^ s3_n) >>11))
-
-   The period of this generator is about 2^88.
-
-   From: P. L'Ecuyer, "Maximally Equidistributed Combined Tausworthe
-   Generators", Mathematics of Computation, 65, 213 (1996), 203--213.
-
-   This is available on the net from L'Ecuyer's home page,
-
-   http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
-   ftp://ftp.iro.umontreal.ca/pub/simulation/lecuyer/papers/tausme.ps
-
-   There is an erratum in the paper "Tables of Maximally
-   Equidistributed Combined LFSR Generators", Mathematics of
-   Computation, 68, 225 (1999), 261--269:
-   http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
-
-        ... the k_j most significant bits of z_j must be non-
-        zero, for each j. (Note: this restriction also applies to the
-        computer code given in [4], but was mistakenly not mentioned in
-        that paper.)
-
-   This affects the seeding procedure by imposing the requirement
-   s1 > 1, s2 > 7, s3 > 15.
-
-*/
-
-#include <linux/types.h>
-#include <linux/module.h>
-#include <linux/jiffies.h>
-#include <linux/random.h>
-#include <linux/smp.h>
-
-#include "compat26.h"
-
-struct rnd_state {
-	u32 s1, s2, s3;
-};
-
-static struct rnd_state net_rand_state[NR_CPUS];
-
-static u32 __random32(struct rnd_state *state)
-{
-#define TAUSWORTHE(s,a,b,c,d) ((s&c)<<d) ^ (((s <<a) ^ s)>>b)
-
-	state->s1 = TAUSWORTHE(state->s1, 13, 19, 4294967294UL, 12);
-	state->s2 = TAUSWORTHE(state->s2, 2, 25, 4294967288UL, 4);
-	state->s3 = TAUSWORTHE(state->s3, 3, 11, 4294967280UL, 17);
-
-	return (state->s1 ^ state->s2 ^ state->s3);
-}
-
-static void __set_random32(struct rnd_state *state, unsigned long s)
-{
-	if (s == 0)
-		s = 1;      /* default seed is 1 */
-
-#define LCG(n) (69069 * n)
-	state->s1 = LCG(s);
-	state->s2 = LCG(state->s1);
-	state->s3 = LCG(state->s2);
-
-	/* "warm it up" */
-	__random32(state);
-	__random32(state);
-	__random32(state);
-	__random32(state);
-	__random32(state);
-	__random32(state);
-}
-
-/**
- *	random32 - pseudo random number generator
- *
- *	A 32 bit pseudo-random number is generated using a fast
- *	algorithm suitable for simulation. This algorithm is NOT
- *	considered safe for cryptographic use.
- */
-u32 random32(void)
-{
-	return __random32(&net_rand_state[smp_processor_id()]);
-}
-
-/**
- *	srandom32 - add entropy to pseudo random number generator
- *	@seed: seed value
- *
- *	Add some additional seeding to the random32() pool.
- *	Note: this pool is per cpu so it only affects current CPU.
- */
-void srandom32(u32 entropy)
-{
-	struct rnd_state *state = &net_rand_state[smp_processor_id()];
-	__set_random32(state, state->s1 ^ entropy);
-}
-
-static int __init random32_reseed(void);
-
-/*
- *	Generate some initially weak seeding values to allow
- *	to start the random32() engine.
- */
-int __init random32_init(void)
-{
-	int i;
-
-	for (i = 0; i < NR_CPUS; i++) {
-		struct rnd_state *state = &net_rand_state[i];
-		__set_random32(state, i + jiffies);
-	}
-	random32_reseed();
-	return 0;
-}
-
-/*
- *	Generate better values after random number generator
- *	is fully initalized.
- */
-static int __init random32_reseed(void)
-{
-	int i;
-	unsigned long seed;
-
-	for (i = 0; i < NR_CPUS; i++) {
-		struct rnd_state *state = &net_rand_state[i];
-
-		get_random_bytes(&seed, sizeof(seed));
-		__set_random32(state, seed);
-	}
-	return 0;
-}
-
-#endif /* kernel < 2.6.19 */
-- 
1.7.0.4





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