[v3] selftests/powerpc: Add test for forking inside transaction

[Rashmica Gupta]

This test does a fork syscall inside a transaction. Basic sniff test to see
if we can enter the kernel during a transaction.

Signed-off-by: Rashmica Gupta <rashmicy at gmail.com>
---
This must be run before tm-signal-stack as after this test is run a reboot
is required -- changed the order of the tests in the Makefile.

 tools/testing/selftests/powerpc/tm/.gitignore |  1 +
 tools/testing/selftests/powerpc/tm/Makefile   |  2 +-
 tools/testing/selftests/powerpc/tm/tm-fork.c  | 42 +++++++++++++++++++++++++++
 3 files changed, 44 insertions(+), 1 deletion(-)
 create mode 100644 tools/testing/selftests/powerpc/tm/tm-fork.c

diff --git a/tools/testing/selftests/powerpc/tm/.gitignore b/tools/testing/selftests/powerpc/tm/.gitignore
index e6668217ccd0..d0c7c97e9b13 100644
--- a/tools/testing/selftests/powerpc/tm/.gitignore
+++ b/tools/testing/selftests/powerpc/tm/.gitignore
@@ -2,3 +2,4 @@ tm-resched-dscr
 tm-syscall
 tm-signal-msr-resv
 tm-signal-stack
+tm-fork
diff --git a/tools/testing/selftests/powerpc/tm/Makefile b/tools/testing/selftests/powerpc/tm/Makefile
index 578572a3700a..56cbb3c839a1 100644
--- a/tools/testing/selftests/powerpc/tm/Makefile
+++ b/tools/testing/selftests/powerpc/tm/Makefile
@@ -1,4 +1,4 @@
-TEST_PROGS := tm-resched-dscr tm-syscall tm-signal-msr-resv tm-signal-stack
+TEST_PROGS := tm-resched-dscr tm-syscall tm-signal-msr-resv tm-fork tm-signal-stack
 
 all: $(TEST_PROGS)
 
diff --git a/tools/testing/selftests/powerpc/tm/tm-fork.c b/tools/testing/selftests/powerpc/tm/tm-fork.c
new file mode 100644
index 000000000000..8d48579b7778
--- /dev/null
+++ b/tools/testing/selftests/powerpc/tm/tm-fork.c
@@ -0,0 +1,42 @@
+/*
+ * Copyright 2015, Michael Neuling, IBM Corp.
+ * Licensed under GPLv2.
+ *
+ * Edited: Rashmica Gupta, Nov 2015
+ *
+ * This test does a fork syscall inside a transaction. Basic sniff test
+ * to see if we can enter the kernel during a transaction.
+ */
+
+#include <errno.h>
+#include <inttypes.h>
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "utils.h"
+#include "tm.h"
+
+int test_fork(void)
+{
+	SKIP_IF(!have_htm());
+
+	asm __volatile__(
+		"tbegin.;"
+		"blt    1f; "
+		"li     0, 2;"  /* fork syscall */
+		"sc  ;"
+		"tend.;"
+		"1: ;"
+		: : : "memory", "r0");
+	/* If we reach here, we've passed.  Otherwise we've probably crashed
+	 * the kernel */
+
+	return 0;
+}
+
+int main(int argc, char *argv[])
+{
+	return test_harness(test_fork, "tm_fork");
+}
-- 
2.5.0