From b76fd695c373d96191d709a6976c41c6825c515b Mon Sep 17 00:00:00 2001
From: Maxim Baryshnikov <barysmax@fel.cvut.cz>
Date: Wed, 25 May 2016 01:09:57 +0200
Subject: [PATCH] Add benchmark for Linux user-space

---
 qemu-launch-scripts/bench-linux.c | 70 +++++++++++++++++++++++++++++++
 1 file changed, 70 insertions(+)
 create mode 100644 qemu-launch-scripts/bench-linux.c

diff --git a/qemu-launch-scripts/bench-linux.c b/qemu-launch-scripts/bench-linux.c
new file mode 100644
index 0000000..e9a3cd5
--- /dev/null
+++ b/qemu-launch-scripts/bench-linux.c
@@ -0,0 +1,70 @@
+
+//#define L4
+
+#include <stdio.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <stdlib.h>
+
+#ifdef L4
+
+#include <l4/util/rdtsc.h>
+#include <l4/sys/kip.h>
+#include <l4/re/env.h>
+
+#endif//L4
+
+#define WORKSET_SIZE (6*1024*1024)
+//#define ALL_WORKSETS_BENCH 
+
+struct s {
+	int dummy[56];
+	struct s *ptr;
+};
+
+struct s array[0x1000000/sizeof(struct s)];
+#define REPEATS (0x20000000)
+
+static __inline__ uint64_t rdtsc(void)
+{
+	uint32_t a, d;
+	//asm("cpuid");
+	asm volatile("rdtsc" : "=a" (a), "=d" (d));
+
+	return (((uint64_t)a) | (((uint64_t)d) << 32));
+}
+
+int main(int argc, char *argv[])
+{
+	
+	unsigned int size;
+#ifdef ALL_WORKSETS_BENCH
+	for (size = 1024; size <= sizeof(array); size *= 2)
+#else //!ALL_WORKSETS_BENCH
+	size = WORKSET_SIZE;
+	if (argc - 1) {
+		char * nxt_cr;
+		size = strtoul(argv[1], &nxt_cr, 0);
+	}
+	while (1)	
+#endif
+	{
+		unsigned int i;
+		for (i=0; i < size / sizeof(array[0]); i++)
+			array[i].ptr = &array[i+1];
+		array[ size / sizeof(array[0]) - 1].ptr = &array[0];
+
+		i = REPEATS;
+		volatile struct s *p = &array[0];
+		uint64_t tic, tac;
+		tic = rdtsc();
+		while (i--) {
+			p = p->ptr;
+		//	printf("%p\n", p);
+		}
+		tac = rdtsc();
+		printf("%d %llu\n", size, (tac - tic) / REPEATS);
+		fflush(stdout);
+	}
+	return 0;	
+}
-- 
2.39.2