init: v1.0.0

grand/drng/entropy/rdtsc/cputime.md

@@ -0,0 +1,17 @@
+# In linux
+```
+#include <pthread.h>
+#include <stdio.h>
+#include <time.h>
+#include <stdint.h>
+
+static long long GetThreadCpuTimeNs() {
+    struct timespec t;
+    if (clock_gettime(CLOCK_THREAD_CPUTIME_ID, &t)) {
+        perror("clock_gettime");
+        return 0;
+    }
+    return t.tv_nsec;
+}
+```
+Makov测试熵估计0.5-0.6

grand/drng/entropy/rdtsc/rdtsc_amd64.s

@@ -0,0 +1,10 @@
+#include "textflag.h"
+
+
+TEXT ·GetCPUTimeStamp(SB), NOSPLIT, $0
+    RDTSCP // save time stamp counter in DX:AX
+    SHLQ $32, DX
+    ORQ  DX, AX 
+    MOVQ AX, res+0(FP)
+    RET
+

grand/drng/entropy/rdtsc/rdtsc_arm64.s

@@ -0,0 +1,9 @@
+#include "textflag.h"
+
+
+TEXT ·GetCPUTimeStamp(SB), NOSPLIT, $0
+    MRS	  CNTVCT_EL0, R0
+    MOVD  R0, res+0(FP)
+    RET
+
+ 

grand/drng/entropy/rdtsc/rdtsc_asm.go

@@ -0,0 +1,9 @@
+//go:build amd64 || arm64
+// +build amd64 arm64
+
+package rdtsc
+
+const SupportRDTSC = true
+
+//go:noescape
+func GetCPUTimeStamp() uint64

grand/drng/entropy/rdtsc/rdtsc_none.go

@@ -0,0 +1,9 @@
+//go:build !amd64 && !arm64
+
+package rdtsc
+
+const SupportRDTSC = false
+
+func GetCPUTimeStamp() uint64 {
+	panic("unsupported")
+}

grand/drng/entropy/rdtsc/rdtsc_test.go

@@ -0,0 +1,12 @@
+package rdtsc
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestRDTSC(t *testing.T) {
+	for i := 0; i < 10; i++ {
+		fmt.Printf("%x\n", GetCPUTimeStamp())
+	}
+}