linux-user: Add debug code to exercise restarting system calls
If DEBUG_ERESTARTSYS is set restart all system calls once. This
is pure debug code for exercising the syscall restart code paths
in the per-architecture cpu main loops.
Signed-off-by: Timothy Edward Baldwin <T.E.Baldwin99@members.leeds.ac.uk>
Message-id: 1441497448-32489-10-git-send-email-T.E.Baldwin99@members.leeds.ac.uk
[PMM: Add comment and a commented-out #define next to the commented-out
generic DEBUG #define; remove the check on TARGET_USE_ERESTARTSYS;
tweak comment message]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index a4a1af7..ced519d 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -110,6 +110,10 @@
CLONE_PARENT_SETTID | CLONE_CHILD_SETTID | CLONE_CHILD_CLEARTID)
//#define DEBUG
+/* Define DEBUG_ERESTARTSYS to force every syscall to be restarted
+ * once. This exercises the codepaths for restart.
+ */
+//#define DEBUG_ERESTARTSYS
//#include <linux/msdos_fs.h>
#define VFAT_IOCTL_READDIR_BOTH _IOR('r', 1, struct linux_dirent [2])
@@ -5871,6 +5875,21 @@
struct statfs stfs;
void *p;
+#if defined(DEBUG_ERESTARTSYS)
+ /* Debug-only code for exercising the syscall-restart code paths
+ * in the per-architecture cpu main loops: restart every syscall
+ * the guest makes once before letting it through.
+ */
+ {
+ static int flag;
+
+ flag = !flag;
+ if (flag) {
+ return -TARGET_ERESTARTSYS;
+ }
+ }
+#endif
+
#ifdef DEBUG
gemu_log("syscall %d", num);
#endif
