[patch V6 36/37] x86/entry: Move paranoid irq tracing out of ASM code

[Thomas Gleixner]

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

---
 arch/x86/entry/entry_64.S |   13 -------------
 arch/x86/kernel/nmi.c     |    3 +++
 2 files changed, 3 insertions(+), 13 deletions(-)

--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -16,7 +16,6 @@
  *
  * Some macro usage:
  * - SYM_FUNC_START/END:Define functions in the symbol table.
- * - TRACE_IRQ_*:	Trace hardirq state for lock debugging.
  * - idtentry:		Define exception entry points.
  */
 #include <linux/linkage.h>
@@ -107,11 +106,6 @@ SYM_CODE_END(native_usergs_sysret64)
 
 SYM_CODE_START(entry_SYSCALL_64)
 	UNWIND_HINT_EMPTY
-	/*
-	 * Interrupts are off on entry.
-	 * We do not frame this tiny irq-off block with TRACE_IRQS_OFF/ON,
-	 * it is too small to ever cause noticeable irq latency.
-	 */
 
 	swapgs
 	/* tss.sp2 is scratch space. */
@@ -462,8 +456,6 @@ SYM_CODE_START(\asmsym)
 
 	UNWIND_HINT_REGS
 
-	TRACE_IRQS_OFF
-
 	movq	%rsp, %rdi		/* pt_regs pointer */
 
 	.if \vector == X86_TRAP_DB
@@ -881,17 +873,13 @@ SYM_CODE_END(paranoid_entry)
  */
 SYM_CODE_START_LOCAL(paranoid_exit)
 	UNWIND_HINT_REGS
-	DISABLE_INTERRUPTS(CLBR_ANY)
-	TRACE_IRQS_OFF
 	testl	%ebx, %ebx			/* swapgs needed? */
 	jnz	.Lparanoid_exit_no_swapgs
-	TRACE_IRQS_IRETQ
 	/* Always restore stashed CR3 value (see paranoid_entry) */
 	RESTORE_CR3	scratch_reg=%rbx save_reg=%r14
 	SWAPGS_UNSAFE_STACK
 	jmp	restore_regs_and_return_to_kernel
 .Lparanoid_exit_no_swapgs:
-	TRACE_IRQS_IRETQ
 	/* Always restore stashed CR3 value (see paranoid_entry) */
 	RESTORE_CR3	scratch_reg=%rbx save_reg=%r14
 	jmp restore_regs_and_return_to_kernel
@@ -1292,7 +1280,6 @@ SYM_CODE_START(asm_exc_nmi)
 	call	paranoid_entry
 	UNWIND_HINT_REGS
 
-	/* paranoidentry exc_nmi(), 0; without TRACE_IRQS_OFF */
 	movq	%rsp, %rdi
 	movq	$-1, %rsi
 	call	exc_nmi
--- a/arch/x86/kernel/nmi.c
+++ b/arch/x86/kernel/nmi.c
@@ -334,6 +334,7 @@ static noinstr void default_do_nmi(struc
 	__this_cpu_write(last_nmi_rip, regs->ip);
 
 	instrumentation_begin();
+	trace_hardirqs_off_prepare();
 	ftrace_nmi_handler_enter();
 
 	handled = nmi_handle(NMI_LOCAL, regs);
@@ -422,6 +423,8 @@ static noinstr void default_do_nmi(struc
 
 out:
 	ftrace_nmi_handler_exit();
+	if (regs->flags & X86_EFLAGS_IF)
+		trace_hardirqs_on_prepare();
 	instrumentation_end();
 }