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authorJens Axboe <axboe@fb.com>2015-05-29 10:44:19 -0600
committerJens Axboe <axboe@fb.com>2015-05-29 11:32:50 -0600
commit16dc07107d2abddccf7e42f684c16c3d8657b324 (patch)
treec0239ccef8f92d6b5f26dde00d3ec91d0a79b727
parent68d96e515825185b232bbc8d2e5b5136b90514be (diff)
downloadfio-16dc07107d2abddccf7e42f684c16c3d8657b324.tar.gz
fio-16dc07107d2abddccf7e42f684c16c3d8657b324.tar.bz2
Add Intel rdrand support
Not wired up. Signed-off-by: Jens Axboe <axboe@fb.com>
-rw-r--r--arch/arch-x86-common.h33
-rw-r--r--arch/arch-x86_64.h30
-rw-r--r--lib/rand.c2
-rw-r--r--lib/rand.h2
4 files changed, 53 insertions, 14 deletions
diff --git a/arch/arch-x86-common.h b/arch/arch-x86-common.h
index 31aa79f1..cbf66b8d 100644
--- a/arch/arch-x86-common.h
+++ b/arch/arch-x86-common.h
@@ -15,8 +15,9 @@ static inline void cpuid(unsigned int op,
#define ARCH_HAVE_INIT
extern int tsc_reliable;
+extern int arch_random;
-static inline int arch_init_intel(unsigned int level)
+static inline void arch_init_intel(unsigned int level)
{
unsigned int eax, ebx, ecx = 0, edx;
@@ -26,47 +27,51 @@ static inline int arch_init_intel(unsigned int level)
eax = 1;
do_cpuid(&eax, &ebx, &ecx, &edx);
if (!(edx & (1U << 4)))
- return 0;
+ return;
/*
* Check for constant rate and synced (across cores) TSC
*/
eax = 0x80000007;
do_cpuid(&eax, &ebx, &ecx, &edx);
- return edx & (1U << 8);
+ tsc_reliable = (edx & (1U << 8)) != 0;
+
+ /*
+ * Check for FDRAND
+ */
+ eax = 0x1;
+ do_cpuid(&eax, &ebx, &ecx, &edx);
+ arch_random = (ecx & (1U << 30)) != 0;
}
-static inline int arch_init_amd(unsigned int level)
+static inline void arch_init_amd(unsigned int level)
{
unsigned int eax, ebx, ecx, edx;
cpuid(0x80000000, &eax, &ebx, &ecx, &edx);
if (eax < 0x80000007)
- return 0;
+ return;
cpuid(0x80000007, &eax, &ebx, &ecx, &edx);
- if (edx & (1 << 8))
- return 1;
-
- return 0;
+ tsc_reliable = (edx & (1U << 8)) != 0;
}
-static inline int arch_init(char *envp[])
+static inline void arch_init(char *envp[])
{
unsigned int level;
char str[13];
+ arch_random = tsc_reliable = 0;
+
cpuid(0, &level, (unsigned int *) &str[0],
(unsigned int *) &str[8],
(unsigned int *) &str[4]);
str[12] = '\0';
if (!strcmp(str, "GenuineIntel"))
- tsc_reliable = arch_init_intel(level);
+ arch_init_intel(level);
else if (!strcmp(str, "AuthenticAMD"))
- tsc_reliable = arch_init_amd(level);
-
- return 0;
+ arch_init_amd(level);
}
#endif
diff --git a/arch/arch-x86_64.h b/arch/arch-x86_64.h
index 61ac75ee..8f33fc54 100644
--- a/arch/arch-x86_64.h
+++ b/arch/arch-x86_64.h
@@ -60,4 +60,34 @@ static inline unsigned long long get_cpu_clock(void)
#define ARCH_HAVE_SSE4_2
#define ARCH_HAVE_CPU_CLOCK
+#define RDRAND_LONG ".byte 0x48,0x0f,0xc7,0xf0"
+#define RDSEED_LONG ".byte 0x48,0x0f,0xc7,0xf8"
+#define RDRAND_RETRY 100
+
+static inline int arch_rand_long(unsigned long *val)
+{
+ int ok;
+
+ asm volatile("1: " RDRAND_LONG "\n\t"
+ "jc 2f\n\t"
+ "decl %0\n\t"
+ "jnz 1b\n\t"
+ "2:"
+ : "=r" (ok), "=a" (*val)
+ : "0" (RDRAND_RETRY));
+
+ return ok;
+}
+
+static inline int arch_rand_seed(unsigned long *seed)
+{
+ unsigned char ok;
+
+ asm volatile(RDSEED_LONG "\n\t"
+ "setc %0"
+ : "=qm" (ok), "=a" (*seed));
+
+ return 0;
+}
+
#endif
diff --git a/lib/rand.c b/lib/rand.c
index 185b679e..1d189a27 100644
--- a/lib/rand.c
+++ b/lib/rand.c
@@ -38,6 +38,8 @@
#include "rand.h"
#include "../hash.h"
+int arch_random;
+
static inline int __seed(unsigned int x, unsigned int m)
{
return (x < m) ? x + m : x;
diff --git a/lib/rand.h b/lib/rand.h
index 089837db..0a577fd3 100644
--- a/lib/rand.h
+++ b/lib/rand.h
@@ -1,6 +1,8 @@
#ifndef FIO_RAND_H
#define FIO_RAND_H
+#include "../arch/arch.h"
+
#define FRAND_MAX (-1U)
struct frand_state {