um: Implement TRACE_IRQFLAGS_SUPPORT

UML enables TRACE_IRQFLAGS_SUPPORT but doesn't actually implement
it. It seems to have been added for lockdep support, but that can't
actually really work well without IRQ flags tracing, as is also
very noisily reported when enabling CONFIG_DEBUG_LOCKDEP.

Implement it now.

Fixes: 711553efa5b8 ("[PATCH] uml: declare in Kconfig our partial LOCKDEP support")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

2 files changed, 8 insertions, 1 deletions

diff --git a/arch/um/include/shared/longjmp.h b/arch/um/include/shared/longjmp.h
index b3315c1f198b..85a1cc290ecb 100644
--- a/arch/um/include/shared/longjmp.h
+++ b/arch/um/include/shared/longjmp.h
@@ -18,7 +18,7 @@ extern void longjmp(jmp_buf, int);
         enable = get_signals(); \
         n = setjmp(*buf); \
         if(n != 0) \
-                set_signals(enable); \
+                set_signals_trace(enable); \
         n; })
 
 #endif
diff --git a/arch/um/include/shared/os.h b/arch/um/include/shared/os.h
index 4a62ac4251a5..fa1909365666 100644
--- a/arch/um/include/shared/os.h
+++ b/arch/um/include/shared/os.h
@@ -232,6 +232,7 @@ extern void block_signals(void);
 extern void unblock_signals(void);
 extern int get_signals(void);
 extern int set_signals(int enable);
+extern int set_signals_trace(int enable);
 extern int os_is_signal_stack(void);
 extern void deliver_alarm(void);
 
@@ -317,4 +318,10 @@ extern unsigned long os_get_top_address(void);
 
 long syscall(long number, ...);
 
+/* irqflags tracing */
+extern void block_signals_trace(void);
+extern void unblock_signals_trace(void);
+extern void um_trace_signals_on(void);
+extern void um_trace_signals_off(void);
+
 #endif