signals: add set_restore_sigmask

This adds the set_restore_sigmask() inline in <linux/thread_info.h> and
replaces every set_thread_flag(TIF_RESTORE_SIGMASK) with a call to it.  No
change, but abstracts the details of the flag protocol from all the calls.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 14 insertions, 1 deletions

diff --git a/include/linux/thread_info.h b/include/linux/thread_info.h
index accd7bad35b0..43d8162c696e 100644
--- a/include/linux/thread_info.h
+++ b/include/linux/thread_info.h
@@ -92,6 +92,19 @@ static inline int test_ti_thread_flag(struct thread_info *ti, int flag)
 #define set_need_resched()      set_thread_flag(TIF_NEED_RESCHED)
 #define clear_need_resched()    clear_thread_flag(TIF_NEED_RESCHED)
 
-#endif
+#ifdef TIF_RESTORE_SIGMASK
+/**
+ * set_restore_sigmask() - make sure saved_sigmask processing gets done
+ *
+ * This sets TIF_RESTORE_SIGMASK and ensures that the arch signal code
+ * will run before returning to user mode, to process the flag.
+ */
+static inline void set_restore_sigmask(void)
+{
+        set_thread_flag(TIF_RESTORE_SIGMASK);
+}
+#endif  /* TIF_RESTORE_SIGMASK */
+
+#endif  /* __KERNEL__ */
 
 #endif /* _LINUX_THREAD_INFO_H */