[RFC 04/30] x86/entry: Move lockdep_sys_exit to prepare_exit_to_usermode

From: Andy Lutomirski
Date: Tue Sep 01 2015 - 18:41:58 EST


Rather than worrying about exactly where LOCKDEP_SYS_EXIT should go
in the asm code, add it to prepare_exit_from_usermode and remove all
of the asm calls that are followed by prepare_exit_to_usermode.

LOCKDEP_SYS_EXIT now appears only in the syscall fast paths.

Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxx>
---
arch/x86/entry/common.c | 2 ++
arch/x86/entry/entry_32.S | 2 --
arch/x86/entry/entry_64.S | 1 -
3 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c
index 80dcc9261ca3..d94a60c16029 100644
--- a/arch/x86/entry/common.c
+++ b/arch/x86/entry/common.c
@@ -220,6 +220,8 @@ __visible void prepare_exit_to_usermode(struct pt_regs *regs)
if (WARN_ON(!irqs_disabled()))
local_irq_disable();

+ lockdep_sys_exit();
+
/*
* In order to return to user mode, we need to have IRQs off with
* none of _TIF_SIGPENDING, _TIF_NOTIFY_RESUME, _TIF_USER_RETURN_NOTIFY,
diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
index b2909bf8cf70..a08ded481aba 100644
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -255,7 +255,6 @@ ret_from_intr:
jb resume_kernel # not returning to v8086 or userspace

ENTRY(resume_userspace)
- LOCKDEP_SYS_EXIT
DISABLE_INTERRUPTS(CLBR_ANY)
TRACE_IRQS_OFF
movl %esp, %eax
@@ -372,7 +371,6 @@ syscall_call:
syscall_after_call:
movl %eax, PT_EAX(%esp) # store the return value
syscall_exit:
- LOCKDEP_SYS_EXIT
jmp syscall_exit_work

restore_all:
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index d3033183ed70..766254c2068b 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -557,7 +557,6 @@ ret_from_intr:
jz retint_kernel

/* Interrupt came from user space */
- LOCKDEP_SYS_EXIT_IRQ
GLOBAL(retint_user)
mov %rsp,%rdi
call prepare_exit_to_usermode
--
2.4.3

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