Port the NetBSD KCSAN runtime to FreeBSD.

Update the NetBSD Kernel Concurrency Sanitizer (KCSAN) runtime to work in
the FreeBSD kernel. It is a useful tool for finding data races between
threads executing on different CPUs.

This can be enabled by enabling KCSAN in the kernel config, or by using the
GENERIC-KCSAN amd64 kernel. It works on amd64 and arm64, however the later
needs a compiler change to allow -fsanitize=thread that KCSAN uses.

Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D22315

3 files changed, 3 insertions, 3 deletions

diff --git a/sys/libkern/strcmp.c b/sys/libkern/strcmp.c
index fadbd30779ad..00220fa6d584 100644
--- a/sys/libkern/strcmp.c
+++ b/sys/libkern/strcmp.c
@@ -41,7 +41,7 @@ __FBSDID("$FreeBSD$");
  * Compare strings.
  */
 int
-strcmp(const char *s1, const char *s2)
+(strcmp)(const char *s1, const char *s2)
 {
 	while (*s1 == *s2++)
 		if (*s1++ == '\0')
diff --git a/sys/libkern/strcpy.c b/sys/libkern/strcpy.c
index 7c61542d9636..8528ed72ac3e 100644
--- a/sys/libkern/strcpy.c
+++ b/sys/libkern/strcpy.c
@@ -35,7 +35,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/libkern.h>
 
 char *
-strcpy(char * __restrict to, const char * __restrict from)
+(strcpy)(char * __restrict to, const char * __restrict from)
 {
 	char *save = to;
 
diff --git a/sys/libkern/strlen.c b/sys/libkern/strlen.c
index 5f2f5867771e..a8c7964f69a3 100644
--- a/sys/libkern/strlen.c
+++ b/sys/libkern/strlen.c
@@ -80,7 +80,7 @@ static const unsigned long mask80 = 0x8080808080808080;
 	} while (0)
 
 size_t
-strlen(const char *str)
+(strlen)(const char *str)
 {
 	const char *p;
 	const unsigned long *lp;