The VFP code enables and disables preemption but doesn't call
into the tracer except for in the VFP bounce code to say that
preemption has been enabled again. Trace the preemption disable
and enable calls made in assembly so that we can accurately
measure how long preemption is disabled while handling VFP
exceptions.

Signed-off-by: Stephen Boyd <sb...@codeaurora.org>
---
 arch/arm/kernel/entry-header.S | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/arch/arm/kernel/entry-header.S b/arch/arm/kernel/entry-header.S
index 130e6a6..75bcb18 100644
--- a/arch/arm/kernel/entry-header.S
+++ b/arch/arm/kernel/entry-header.S
@@ -165,19 +165,33 @@
 
        .macro preempt_enable_no_resched, tsk, cnt
 #ifdef CONFIG_PREEMPT_COUNT
+#if defined(CONFIG_DEBUG_PREEMPT) || defined(CONFIG_PREEMPT_TRACER)
+       stmdb   sp!, {r0-r3, ip, lr}
+       mov     r0, #1
+       bl      sub_preempt_count
+       ldmia   sp!, {r0-r3, ip, lr}
+#else
        get_thread_info \tsk
        ldr     \cnt, [\tsk, #TI_PREEMPT]       @ get preempt count
        sub     \cnt, \cnt, #1                  @ decrement it
        str     \cnt, [\tsk, #TI_PREEMPT]
 #endif
+#endif
        .endm
 
        .macro preempt_disable, tsk, cnt
 #ifdef CONFIG_PREEMPT_COUNT
+#if defined(CONFIG_DEBUG_PREEMPT) || defined(CONFIG_PREEMPT_TRACER)
+       stmdb   sp!, {r0-r3, ip, lr}
+       mov     r0, #1
+       bl      add_preempt_count
+       ldmia   sp!, {r0-r3, ip, lr}
+#else
        ldr     \cnt, [\tsk, #TI_PREEMPT]       @ get preempt count
        add     \cnt, \cnt, #1                  @ increment it
        str     \cnt, [\tsk, #TI_PREEMPT]
 #endif
+#endif
        .endm
 
 /*
-- 
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