[patch 4/8] x86/entry: Move irq tracing on syscall entry to C-code
From: Thomas Gleixner
Date:  Tue Feb 25 2020 - 18:30:03 EST
Now that the C entry points are safe, move the irq flags tracing code into
the entry helper.
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
 arch/x86/entry/common.c          |    5 +++++
 arch/x86/entry/entry_32.S        |   12 ------------
 arch/x86/entry/entry_64.S        |    2 --
 arch/x86/entry/entry_64_compat.S |   18 ------------------
 4 files changed, 5 insertions(+), 32 deletions(-)
--- a/arch/x86/entry/common.c
+++ b/arch/x86/entry/common.c
@@ -57,6 +57,11 @@ static inline void enter_from_user_mode(
  */
 static __always_inline void syscall_entry_fixups(void)
 {
+	/*
+	 * Usermode is traced as interrupts enabled, but the syscall entry
+	 * mechanisms disable interrupts. Tell the tracer.
+	 */
+	trace_hardirqs_off();
 	enter_from_user_mode();
 	local_irq_enable();
 }
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -960,12 +960,6 @@ SYM_FUNC_START(entry_SYSENTER_32)
 	jnz	.Lsysenter_fix_flags
 .Lsysenter_flags_fixed:
 
-	/*
-	 * User mode is traced as though IRQs are on, and SYSENTER
-	 * turned them off.
-	 */
-	TRACE_IRQS_OFF
-
 	movl	%esp, %eax
 	call	do_fast_syscall_32
 	/* XEN PV guests always use IRET path */
@@ -1075,12 +1069,6 @@ SYM_FUNC_START(entry_INT80_32)
 
 	SAVE_ALL pt_regs_ax=$-ENOSYS switch_stacks=1	/* save rest */
 
-	/*
-	 * User mode is traced as though IRQs are on, and the interrupt gate
-	 * turned them off.
-	 */
-	TRACE_IRQS_OFF
-
 	movl	%esp, %eax
 	call	do_int80_syscall_32
 .Lsyscall_32_done:
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -167,8 +167,6 @@ SYM_INNER_LABEL(entry_SYSCALL_64_after_h
 
 	PUSH_AND_CLEAR_REGS rax=$-ENOSYS
 
-	TRACE_IRQS_OFF
-
 	/* IRQs are off. */
 	movq	%rax, %rdi
 	movq	%rsp, %rsi
--- a/arch/x86/entry/entry_64_compat.S
+++ b/arch/x86/entry/entry_64_compat.S
@@ -129,12 +129,6 @@ SYM_FUNC_START(entry_SYSENTER_compat)
 	jnz	.Lsysenter_fix_flags
 .Lsysenter_flags_fixed:
 
-	/*
-	 * User mode is traced as though IRQs are on, and SYSENTER
-	 * turned them off.
-	 */
-	TRACE_IRQS_OFF
-
 	movq	%rsp, %rdi
 	call	do_fast_syscall_32
 	/* XEN PV guests always use IRET path */
@@ -247,12 +241,6 @@ SYM_INNER_LABEL(entry_SYSCALL_compat_aft
 	pushq   $0			/* pt_regs->r15 = 0 */
 	xorl	%r15d, %r15d		/* nospec   r15 */
 
-	/*
-	 * User mode is traced as though IRQs are on, and SYSENTER
-	 * turned them off.
-	 */
-	TRACE_IRQS_OFF
-
 	movq	%rsp, %rdi
 	call	do_fast_syscall_32
 	/* XEN PV guests always use IRET path */
@@ -403,12 +391,6 @@ SYM_CODE_START(entry_INT80_compat)
 	xorl	%r15d, %r15d		/* nospec   r15 */
 	cld
 
-	/*
-	 * User mode is traced as though IRQs are on, and the interrupt
-	 * gate turned them off.
-	 */
-	TRACE_IRQS_OFF
-
 	movq	%rsp, %rdi
 	call	do_int80_syscall_32
 .Lsyscall_32_done: