TIF_NOTIFY_SIGNAL handling in xtensa assembly is implemented
incorrectly: there should be a call to do_notify_resume when either
TIF_SIGPENDING, TIF_NOTIFY_RESUME or TIF_NOTIFY_SIGNAL bit is set in the
thread_info::flags. The straightforward way to do it would be

    _bbsi.l a4, TIF_NEED_RESCHED, 3f
    _bbsi.l a4, TIF_NOTIFY_RESUME, 2f
    _bbsi.l a4, TIF_NOTIFY_SIGNAL, 2f
    _bbci.l a4, TIF_SIGPENDING, 5f

Optimize it a little bit and use bit mask and bnone opcode to skip
do_notify_resume invocation. Shuffle _TIF_* flags a bit so that used bit
mask fits into the immediate field of movi opcode.

Fixes: 4c6a9dcd4d13 ("xtensa: add support for TIF_NOTIFY_SIGNAL")
Cc: Jens Axboe <ax...@kernel.dk>
Signed-off-by: Max Filippov <jcmvb...@gmail.com>
---
 arch/xtensa/include/asm/thread_info.h | 7 ++++---
 arch/xtensa/kernel/entry.S            | 5 ++---
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/xtensa/include/asm/thread_info.h 
b/arch/xtensa/include/asm/thread_info.h
index 6ea521b8e2ec..a312333a9add 100644
--- a/arch/xtensa/include/asm/thread_info.h
+++ b/arch/xtensa/include/asm/thread_info.h
@@ -111,22 +111,23 @@ static inline struct thread_info 
*current_thread_info(void)
 #define TIF_NEED_RESCHED       2       /* rescheduling necessary */
 #define TIF_SINGLESTEP         3       /* restore singlestep on return to user 
mode */
 #define TIF_SYSCALL_TRACEPOINT 4       /* syscall tracepoint instrumentation */
-#define TIF_MEMDIE             5       /* is terminating due to OOM killer */
+#define TIF_NOTIFY_SIGNAL      5       /* signal notifications exist */
 #define TIF_RESTORE_SIGMASK    6       /* restore signal mask in do_signal() */
 #define TIF_NOTIFY_RESUME      7       /* callback before returning to user */
 #define TIF_DB_DISABLED                8       /* debug trap disabled for 
syscall */
 #define TIF_SYSCALL_AUDIT      9       /* syscall auditing active */
 #define TIF_SECCOMP            10      /* secure computing */
-#define TIF_NOTIFY_SIGNAL      11      /* signal notifications exist */
+#define TIF_MEMDIE             11      /* is terminating due to OOM killer */
 
 #define _TIF_SYSCALL_TRACE     (1<<TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING                (1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED      (1<<TIF_NEED_RESCHED)
 #define _TIF_SINGLESTEP                (1<<TIF_SINGLESTEP)
 #define _TIF_SYSCALL_TRACEPOINT        (1<<TIF_SYSCALL_TRACEPOINT)
+#define _TIF_NOTIFY_SIGNAL     (1<<TIF_NOTIFY_SIGNAL)
+#define _TIF_NOTIFY_RESUME     (1<<TIF_NOTIFY_RESUME)
 #define _TIF_SYSCALL_AUDIT     (1<<TIF_SYSCALL_AUDIT)
 #define _TIF_SECCOMP           (1<<TIF_SECCOMP)
-#define _TIF_NOTIFY_SIGNAL     (1<<TIF_NOTIFY_SIGNAL)
 
 #define _TIF_WORK_MASK         (_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP | \
                                 _TIF_SYSCALL_TRACEPOINT | \
diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S
index 7f733f40fef0..a367c464217d 100644
--- a/arch/xtensa/kernel/entry.S
+++ b/arch/xtensa/kernel/entry.S
@@ -500,9 +500,8 @@ common_exception_return:
         */
 
        _bbsi.l a4, TIF_NEED_RESCHED, 3f
-       _bbsi.l a4, TIF_NOTIFY_RESUME, 2f
-       _bbci.l a4, TIF_SIGPENDING, 5f
-       _bbci.l a4, TIF_NOTIFY_SIGNAL, 5f
+       movi    a2, _TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NOTIFY_SIGNAL
+       bnone   a2, a4, 5f
 
 2:     l32i    a4, a1, PT_DEPC
        bgeui   a4, VALID_DOUBLE_EXCEPTION_ADDRESS, 4f
-- 
2.20.1

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