[PATCH] mips: add support for TIF_NOTIFY_SIGNAL

[Jens Axboe <axboe@kernel.dk>]

Wire up TIF_NOTIFY_SIGNAL handling for mips.

Cc: linux-mips@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

5.11 has support queued up for TIF_NOTIFY_SIGNAL, see this posting
for details:

https://lore.kernel.org/io-uring/20201026203230.386348-1-axboe@kernel.dk/

As part of that work, I'm adding TIF_NOTIFY_SIGNAL support to all archs,
as that will enable a set of cleanups once all of them support it. I'm
happy carrying this patch if need be, or it can be funelled through the
arch tree. Let me know.

 arch/mips/include/asm/thread_info.h | 4 +++-
 arch/mips/kernel/signal.c           | 2 +-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/mips/include/asm/thread_info.h b/arch/mips/include/asm/thread_info.h
index ee26f9a4575d..e2c352da3877 100644
--- a/arch/mips/include/asm/thread_info.h
+++ b/arch/mips/include/asm/thread_info.h
@@ -115,6 +115,7 @@ static inline struct thread_info *current_thread_info(void)
 #define TIF_SECCOMP		4	/* secure computing */
 #define TIF_NOTIFY_RESUME	5	/* callback before returning to user */
 #define TIF_UPROBE		6	/* breakpointed or singlestepping */
+#define TIF_NOTIFY_SIGNAL	7	/* signal notifications exist */
 #define TIF_RESTORE_SIGMASK	9	/* restore signal mask in do_signal() */
 #define TIF_USEDFPU		16	/* FPU was used by this task this quantum (SMP) */
 #define TIF_MEMDIE		18	/* is terminating due to OOM killer */
@@ -139,6 +140,7 @@ static inline struct thread_info *current_thread_info(void)
 #define _TIF_SECCOMP		(1<<TIF_SECCOMP)
 #define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
 #define _TIF_UPROBE		(1<<TIF_UPROBE)
+#define _TIF_NOTIFY_SIGNAL	(1<<TIF_NOTIFY_SIGNAL)
 #define _TIF_USEDFPU		(1<<TIF_USEDFPU)
 #define _TIF_NOHZ		(1<<TIF_NOHZ)
 #define _TIF_FIXADE		(1<<TIF_FIXADE)
@@ -164,7 +166,7 @@ static inline struct thread_info *current_thread_info(void)
 /* work to do on interrupt/exception return */
 #define _TIF_WORK_MASK		\
 	(_TIF_SIGPENDING | _TIF_NEED_RESCHED | _TIF_NOTIFY_RESUME |	\
-	 _TIF_UPROBE)
+	 _TIF_UPROBE | _TIF_NOTIFY_SIGNAL)
 /* work to do on any return to u-space */
 #define _TIF_ALLWORK_MASK	(_TIF_NOHZ | _TIF_WORK_MASK |		\
 				 _TIF_WORK_SYSCALL_EXIT |		\
diff --git a/arch/mips/kernel/signal.c b/arch/mips/kernel/signal.c
index 50d0515bea21..f1e985109da0 100644
--- a/arch/mips/kernel/signal.c
+++ b/arch/mips/kernel/signal.c
@@ -903,7 +903,7 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused,
 		uprobe_notify_resume(regs);
 
 	/* deal with pending signal delivery */
-	if (thread_info_flags & _TIF_SIGPENDING)
+	if (thread_info_flags & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL))
 		do_signal(regs);
 
 	if (thread_info_flags & _TIF_NOTIFY_RESUME) {
-- 
2.29.0

-- 
Jens Axboe