[ARM] Add ARM irqtrace support

This adds support for irqtrace for lockdep on ARM.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

2 files changed, 17 insertions, 0 deletions

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index f81a62380add..d9376f048ed7 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -51,6 +51,10 @@ config GENERIC_HARDIRQS
         bool
         default y
 
+config TRACE_IRQFLAGS_SUPPORT
+        bool
+        default y
+
 config HARDIRQS_SW_RESEND
         bool
         default y
diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S
index de4e33137901..bd623b73445f 100644
--- a/arch/arm/kernel/entry-armv.S
+++ b/arch/arm/kernel/entry-armv.S
@@ -191,6 +191,9 @@ __dabt_svc:
 __irq_svc:
         svc_entry
 
+#ifdef CONFIG_TRACE_IRQFLAGS
+        bl      trace_hardirqs_off
+#endif
 #ifdef CONFIG_PREEMPT
         get_thread_info tsk
         ldr     r8, [tsk, #TI_PREEMPT]          @ get preempt count
@@ -211,6 +214,10 @@ preempt_return:
 #endif
         ldr     r0, [sp, #S_PSR]                @ irqs are already disabled
         msr     spsr_cxsf, r0
+#ifdef CONFIG_TRACE_IRQFLAGS
+        tst     r0, #PSR_I_BIT
+        bleq    trace_hardirqs_on
+#endif
         ldmia   sp, {r0 - pc}^                  @ load r0 - pc, cpsr
 
         .ltorg
@@ -398,6 +405,9 @@ __dabt_usr:
 __irq_usr:
         usr_entry
 
+#ifdef CONFIG_TRACE_IRQFLAGS
+        bl      trace_hardirqs_off
+#endif
         get_thread_info tsk
 #ifdef CONFIG_PREEMPT
         ldr     r8, [tsk, #TI_PREEMPT]          @ get preempt count
@@ -412,6 +422,9 @@ __irq_usr:
         teq     r0, r7
         strne   r0, [r0, -r0]
 #endif
+#ifdef CONFIG_TRACE_IRQFLAGS
+        bl      trace_hardirqs_on
+#endif
 
         mov     why, #0
         b       ret_to_user