s390/mcck: optimize user mode check in case of !CONFIG_KVM

In case of the !CONFIG_KVM use "jz" instead of "jnz" when
detecting user mode and get rid of unnecessary jump as result.

Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Christia Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index 3287cb0d89ad0efa3cec5d75249d8ab05db011e5..ff715cc2b77ba9cf3f61b28eb51f09997ce63121 100644 (file)
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -555,15 +555,17 @@ ENTRY(mcck_int_handler)
        jno     .Lmcck_panic
 4:     ssm     __LC_PGM_NEW_PSW        # turn dat on, keep irqs off
        tmhh    %r8,0x0001                      # interrupting from user ?
-       jnz     .Lmcck_user
 #if IS_ENABLED(CONFIG_KVM)
+       jnz     .Lmcck_user
        OUTSIDE %r9,.Lsie_gmap,.Lsie_done,.Lmcck_stack
        OUTSIDE %r9,.Lsie_entry,.Lsie_skip,5f
        oi      __LC_CPU_FLAGS+7, _CIF_MCCK_GUEST
 5:     BPENTER __SF_SIE_FLAGS(%r15),(_TIF_ISOLATE_BP|_TIF_ISOLATE_BP_GUEST)
        SIEEXIT
-#endif
        j       .Lmcck_stack
+#else
+       jz      .Lmcck_stack
+#endif
 .Lmcck_user:
        BPENTER __TI_flags(%r12),_TIF_ISOLATE_BP
 .Lmcck_stack: