powerpc/64s: move ret_from_fork etc above __end_soft_masked

Code which runs with interrupts enabled should be moved above
__end_soft_masked where possible, because maskable interrupts that hit
below that symbol will need to consult the soft mask table, which is an
extra cost.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210630074621.2109197-10-npiggin@gmail.com

diff --git a/arch/powerpc/kernel/interrupt_64.S b/arch/powerpc/kernel/interrupt_64.S
index c4336e2e2ce893506f4ebce486bedb97b45c12b9..4063e8a3f70412503731ac5bdb62e6b63c017f55 100644 (file)
--- a/arch/powerpc/kernel/interrupt_64.S
+++ b/arch/powerpc/kernel/interrupt_64.S
@@ -449,32 +449,6 @@ _ASM_NOKPROBE_SYMBOL(tabort_syscall)
        b       .       /* prevent speculative execution */
 #endif
 
-#ifdef CONFIG_PPC_BOOK3S
-_GLOBAL(ret_from_fork_scv)
-       bl      schedule_tail
-       REST_NVGPRS(r1)
-       li      r3,0    /* fork() return value */
-       b       .Lsyscall_vectored_common_exit
-#endif
-
-_GLOBAL(ret_from_fork)
-       bl      schedule_tail
-       REST_NVGPRS(r1)
-       li      r3,0    /* fork() return value */
-       b       .Lsyscall_exit
-
-_GLOBAL(ret_from_kernel_thread)
-       bl      schedule_tail
-       REST_NVGPRS(r1)
-       mtctr   r14
-       mr      r3,r15
-#ifdef PPC64_ELF_ABI_v2
-       mr      r12,r14
-#endif
-       bctrl
-       li      r3,0
-       b       .Lsyscall_exit
-
        /*
         * If MSR EE/RI was never enabled, IRQs not reconciled, NVGPRs not
         * touched, no exit work created, then this can be used.
@@ -768,3 +742,29 @@ interrupt_return_macro hsrr
 __end_soft_masked:
 DEFINE_FIXED_SYMBOL(__end_soft_masked)
 #endif /* CONFIG_PPC_BOOK3S */
+
+#ifdef CONFIG_PPC_BOOK3S
+_GLOBAL(ret_from_fork_scv)
+       bl      schedule_tail
+       REST_NVGPRS(r1)
+       li      r3,0    /* fork() return value */
+       b       .Lsyscall_vectored_common_exit
+#endif
+
+_GLOBAL(ret_from_fork)
+       bl      schedule_tail
+       REST_NVGPRS(r1)
+       li      r3,0    /* fork() return value */
+       b       .Lsyscall_exit
+
+_GLOBAL(ret_from_kernel_thread)
+       bl      schedule_tail
+       REST_NVGPRS(r1)
+       mtctr   r14
+       mr      r3,r15
+#ifdef PPC64_ELF_ABI_v2
+       mr      r12,r14
+#endif
+       bctrl
+       li      r3,0
+       b       .Lsyscall_exit