3 files changed, 5 insertions, 6 deletions

diff --git a/arch/um/include/os.h b/arch/um/include/os.h
index 8629bd191492..5c74da410451 100644
--- a/arch/um/include/os.h
+++ b/arch/um/include/os.h
@@ -192,7 +192,9 @@ extern int os_process_parent(int pid);
 extern void os_stop_process(int pid);
 extern void os_kill_process(int pid, int reap_child);
 extern void os_kill_ptraced_process(int pid, int reap_child);
+#ifdef UML_CONFIG_MODE_TT
 extern void os_usr1_process(int pid);
+#endif
 extern long os_ptrace_ldt(long pid, long addr, long data);
 
 extern int os_getpid(void);
@@ -261,7 +263,6 @@ extern void block_signals(void);
 extern void unblock_signals(void);
 extern int get_signals(void);
 extern int set_signals(int enable);
-extern void os_usr1_signal(int on);
 
 /* trap.c */
 extern void os_fill_handlinfo(struct kern_handlers h);
diff --git a/arch/um/os-Linux/process.c b/arch/um/os-Linux/process.c
index c692a192957a..76bdd6712417 100644
--- a/arch/um/os-Linux/process.c
+++ b/arch/um/os-Linux/process.c
@@ -21,6 +21,7 @@
 #include "longjmp.h"
 #include "skas_ptrace.h"
 #include "kern_constants.h"
+#include "uml-config.h"
 
 #define ARBITRARY_ADDR -1
 #define FAILURE_PID    -1
@@ -131,10 +132,12 @@ void os_kill_ptraced_process(int pid, int reap_child)
                 CATCH_EINTR(waitpid(pid, NULL, 0));
 }
 
+#ifdef UML_CONFIG_MODE_TT
 void os_usr1_process(int pid)
 {
         kill(pid, SIGUSR1);
 }
+#endif
 
 /* Don't use the glibc version, which caches the result in TLS. It misses some
  * syscalls, and also breaks with clone(), which does not unshare the TLS.
diff --git a/arch/um/os-Linux/signal.c b/arch/um/os-Linux/signal.c
index b897e8592d77..266768629fee 100644
--- a/arch/um/os-Linux/signal.c
+++ b/arch/um/os-Linux/signal.c
@@ -243,8 +243,3 @@ int set_signals(int enable)
 
         return ret;
 }
-
-void os_usr1_signal(int on)
-{
-        change_sig(SIGUSR1, on);
-}