selftests/powerpc: Add uaccess flush test

Also based on the RFI and entry flush tests, it counts the L1D misses
by doing a syscall that does user access: uname, in this case.

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
[dja: forward port, rename function]
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210225061949.1213404-1-dja@axtens.net

1 files changed, 13 insertions, 0 deletions

diff --git a/tools/testing/selftests/powerpc/security/flush_utils.c b/tools/testing/selftests/powerpc/security/flush_utils.c
index 0c3c4c40c7fb..4d95965cb751 100644
--- a/tools/testing/selftests/powerpc/security/flush_utils.c
+++ b/tools/testing/selftests/powerpc/security/flush_utils.c
@@ -13,6 +13,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <stdio.h>
+#include <sys/utsname.h>
 #include "utils.h"
 #include "flush_utils.h"
 
@@ -35,6 +36,18 @@ void syscall_loop(char *p, unsigned long iterations,
 	}
 }
 
+void syscall_loop_uaccess(char *p, unsigned long iterations,
+			  unsigned long zero_size)
+{
+	struct utsname utsname;
+
+	for (unsigned long i = 0; i < iterations; i++) {
+		for (unsigned long j = 0; j < zero_size; j += CACHELINE_SIZE)
+			load(p + j);
+		uname(&utsname);
+	}
+}
+
 static void sigill_handler(int signr, siginfo_t *info, void *unused)
 {
 	static int warned;