[3.8.y.z extended stable] Patch "ARM: entry: move IRQ tracing exit into svc_exit" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    ARM: entry: move IRQ tracing exit into svc_exit

to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue

This patch is scheduled to be released in version 3.8.13.14.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.8.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From f6a72b5e02d4cedfac4d19ac966d866f1ea89c3b Mon Sep 17 00:00:00 2001
From: Russell King <rmk+kernel at arm.linux.org.uk>
Date: Thu, 28 Mar 2013 12:57:40 +0000
Subject: ARM: entry: move IRQ tracing exit into svc_exit

commit 9b56febea22003c424f11248908b534eba0f1eeb upstream.

The IRQ tracing exit path is much the same between all SVC mode
exits, so move this into the svc_exit macro.  Use a macro parameter
to identify the IRQ case, which is the only different case there is.

Signed-off-by: Russell King <rmk+kernel at arm.linux.org.uk>
[ kamal: 3.8 stable prereq for
  e16b31b ARM: 7876/1: clear Thumb-2 IT state on exception handling ]
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 arch/arm/kernel/entry-armv.S   | 27 +--------------------------
 arch/arm/kernel/entry-header.S | 32 ++++++++++++++++++++++++++++++--
 2 files changed, 31 insertions(+), 28 deletions(-)

diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S
index 5492d72..a716ea9 100644
--- a/arch/arm/kernel/entry-armv.S
+++ b/arch/arm/kernel/entry-armv.S
@@ -197,13 +197,6 @@ __dabt_svc:
 	@ IRQs off again before pulling preserved data off the stack
 	@
 	disable_irq_notrace
-
-#ifdef CONFIG_TRACE_IRQFLAGS
-	tst	r5, #PSR_I_BIT
-	bleq	trace_hardirqs_on
-	tst	r5, #PSR_I_BIT
-	blne	trace_hardirqs_off
-#endif
 	svc_exit r5				@ return from exception
  UNWIND(.fnend		)
 ENDPROC(__dabt_svc)
@@ -223,12 +216,7 @@ __irq_svc:
 	blne	svc_preempt
 #endif

-#ifdef CONFIG_TRACE_IRQFLAGS
-	@ The parent context IRQs must have been enabled to get here in
-	@ the first place, so there's no point checking the PSR I bit.
-	bl	trace_hardirqs_on
-#endif
-	svc_exit r5				@ return from exception
+	svc_exit r5, irq = 1			@ return from exception
  UNWIND(.fnend		)
 ENDPROC(__irq_svc)

@@ -305,12 +293,6 @@ __und_svc_finish:
 	@ restore SPSR and restart the instruction
 	@
 	ldr	r5, [sp, #S_PSR]		@ Get SVC cpsr
-#ifdef CONFIG_TRACE_IRQFLAGS
-	tst	r5, #PSR_I_BIT
-	bleq	trace_hardirqs_on
-	tst	r5, #PSR_I_BIT
-	blne	trace_hardirqs_off
-#endif
 	svc_exit r5				@ return from exception
  UNWIND(.fnend		)
 ENDPROC(__und_svc)
@@ -325,13 +307,6 @@ __pabt_svc:
 	@ IRQs off again before pulling preserved data off the stack
 	@
 	disable_irq_notrace
-
-#ifdef CONFIG_TRACE_IRQFLAGS
-	tst	r5, #PSR_I_BIT
-	bleq	trace_hardirqs_on
-	tst	r5, #PSR_I_BIT
-	blne	trace_hardirqs_off
-#endif
 	svc_exit r5				@ return from exception
  UNWIND(.fnend		)
 ENDPROC(__pabt_svc)
diff --git a/arch/arm/kernel/entry-header.S b/arch/arm/kernel/entry-header.S
index 9a8531e..0bf15e5 100644
--- a/arch/arm/kernel/entry-header.S
+++ b/arch/arm/kernel/entry-header.S
@@ -74,7 +74,21 @@
 	.endm

 #ifndef CONFIG_THUMB2_KERNEL
-	.macro	svc_exit, rpsr
+	.macro	svc_exit, rpsr, irq = 0
+	.if	\irq != 0
+#ifdef CONFIG_TRACE_IRQFLAGS
+	@ The parent context IRQs must have been enabled to get here in
+	@ the first place, so there's no point checking the PSR I bit.
+	bl	trace_hardirqs_on
+#endif
+	.else
+#ifdef CONFIG_TRACE_IRQFLAGS
+	tst	\rpsr, #PSR_I_BIT
+	bleq	trace_hardirqs_on
+	tst	\rpsr, #PSR_I_BIT
+	blne	trace_hardirqs_off
+#endif
+	.endif
 	msr	spsr_cxsf, \rpsr
 #if defined(CONFIG_CPU_V6)
 	ldr	r0, [sp]
@@ -120,7 +134,21 @@
 	mov	pc, \reg
 	.endm
 #else	/* CONFIG_THUMB2_KERNEL */
-	.macro	svc_exit, rpsr
+	.macro	svc_exit, rpsr, irq = 0
+	.if	\irq != 0
+#ifdef CONFIG_TRACE_IRQFLAGS
+	@ The parent context IRQs must have been enabled to get here in
+	@ the first place, so there's no point checking the PSR I bit.
+	bl	trace_hardirqs_on
+#endif
+	.else
+#ifdef CONFIG_TRACE_IRQFLAGS
+	tst	\rpsr, #PSR_I_BIT
+	bleq	trace_hardirqs_on
+	tst	\rpsr, #PSR_I_BIT
+	blne	trace_hardirqs_off
+#endif
+	.endif
 	ldr	lr, [sp, #S_SP]			@ top of the stack
 	ldrd	r0, r1, [sp, #S_LR]		@ calling lr and pc
 	clrex					@ clear the exclusive monitor
--
1.8.3.2