From b64661e6a2000fe3e41458dc27a9810ea1c48f6e Mon Sep 17 00:00:00 2001
From: compudj <compudj@04897980-b3bd-0310-b5e0-8ef037075253>
Date: Sat, 3 Jun 2006 09:49:17 +0000
Subject: [PATCH] add test cmpxchg

git-svn-id: http://ltt.polymtl.ca/svn@1878 04897980-b3bd-0310-b5e0-8ef037075253
---
 tests/kernel/Makefile              |   1 +
 tests/kernel/test-cmpxchg-nolock.c | 105 +++++++++++++++++++++++++++++
 tests/kernel/test-cmpxchg.c        |   2 +-
 3 files changed, 107 insertions(+), 1 deletion(-)
 create mode 100644 tests/kernel/test-cmpxchg-nolock.c

diff --git a/tests/kernel/Makefile b/tests/kernel/Makefile
index b0a5bb43..c134b337 100644
--- a/tests/kernel/Makefile
+++ b/tests/kernel/Makefile
@@ -9,6 +9,7 @@ ifneq ($(CONFIG_LTT),)
 	obj-m += test-printk-effect.o
 endif
 	obj-m += test-cmpxchg.o
+	obj-m += test-cmpxchg-nolock.o
 
 else
 	KERNELDIR ?= /lib/modules/$(shell uname -r)/build
diff --git a/tests/kernel/test-cmpxchg-nolock.c b/tests/kernel/test-cmpxchg-nolock.c
new file mode 100644
index 00000000..5f3d7981
--- /dev/null
+++ b/tests/kernel/test-cmpxchg-nolock.c
@@ -0,0 +1,105 @@
+/* test-cmpxchg.c
+ *
+ * Test time spent in a LTTng instrumentation probe.
+ */
+
+
+#include <linux/config.h>
+#include <linux/jiffies.h>
+#include <linux/compiler.h>
+#include <linux/init.h>
+#include <linux/module.h>
+
+
+#define cmpxchg_up(ptr,o,n)\
+	((__typeof__(*(ptr)))__cmpxchg_up((ptr),(unsigned long)(o),\
+					(unsigned long)(n),sizeof(*(ptr))))
+static inline unsigned long __cmpxchg_up(volatile void *ptr, unsigned long old,
+				      unsigned long new, int size)
+{
+	unsigned long prev;
+	switch (size) {
+	case 1:
+		__asm__ __volatile__("cmpxchgb %b1,%2"
+				     : "=a"(prev)
+				     : "q"(new), "m"(*__xg(ptr)), "0"(old)
+				     : "memory");
+		return prev;
+	case 2:
+		__asm__ __volatile__("cmpxchgw %w1,%2"
+				     : "=a"(prev)
+				     : "r"(new), "m"(*__xg(ptr)), "0"(old)
+				     : "memory");
+		return prev;
+	case 4:
+		__asm__ __volatile__("cmpxchgl %1,%2"
+				     : "=a"(prev)
+				     : "r"(new), "m"(*__xg(ptr)), "0"(old)
+				     : "memory");
+		return prev;
+	}
+	return old;
+}
+
+
+#define NR_LOOPS 20000
+
+volatile int test_val = 100;
+
+
+static inline void do_test(void)
+{
+	int val, ret;
+
+	val = test_val;
+	
+	ret = cmpxchg_up(&test_val, val, val+1);
+}
+
+static int ltt_test_init(void)
+{
+	unsigned int i;
+	cycles_t time1, time2, time;
+	cycles_t max_time = 0, min_time = 18446744073709551615ULL; /* (2^64)-1 */
+	cycles_t tot_time = 0;
+	unsigned long flags;
+	printk(KERN_ALERT "test init\n");
+	
+	local_irq_save(flags);
+	time1 = get_cycles();
+	for(i=0; i<NR_LOOPS; i++) {
+		//for(int j=0; j<10; j++) {
+		do_test();
+		//}
+		//max_time = max(max_time, time);
+		//min_time = min(min_time, time);
+		//printk("val : %d\n", test_val);
+	}
+	time2 = get_cycles();
+	local_irq_restore(flags);
+	time = time2 - time1;
+	tot_time += time;
+
+	printk(KERN_ALERT "test results : time non locked cmpxchg\n");
+	printk(KERN_ALERT "number of loops : %d\n", NR_LOOPS);
+	printk(KERN_ALERT "total time : %llu\n", tot_time);
+	//printk(KERN_ALERT "min : %llu\n", min_time);
+	//printk(KERN_ALERT "max : %llu\n", max_time);
+
+	printk(KERN_ALERT "test end\n");
+	
+	return -EAGAIN; /* Fail will directly unload the module */
+}
+
+static void ltt_test_exit(void)
+{
+	printk(KERN_ALERT "test exit\n");
+}
+
+module_init(ltt_test_init)
+module_exit(ltt_test_exit)
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Mathieu Desnoyers");
+MODULE_DESCRIPTION("Linux Trace Toolkit Test");
+
diff --git a/tests/kernel/test-cmpxchg.c b/tests/kernel/test-cmpxchg.c
index 69a25334..ea5120d3 100644
--- a/tests/kernel/test-cmpxchg.c
+++ b/tests/kernel/test-cmpxchg.c
@@ -50,7 +50,7 @@ static int ltt_test_init(void)
 	time = time2 - time1;
 	tot_time += time;
 
-	printk(KERN_ALERT "test results : time per probe\n");
+	printk(KERN_ALERT "test results : time for cmpxchg\n");
 	printk(KERN_ALERT "number of loops : %d\n", NR_LOOPS);
 	printk(KERN_ALERT "total time : %llu\n", tot_time);
 	//printk(KERN_ALERT "min : %llu\n", min_time);
-- 
2.34.1