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From d13e5edd7284bedcf5952e1b6490e39ad843cb91 Mon Sep 17 00:00:00 2001
From: Todd Android Poynor <toddpoynor@google.com>
Date: Thu, 23 Dec 2010 01:52:44 +0100
Subject: [PATCH 12/66] ARM: 6540/1: Stop irqsoff trace on return to user
If the irqsoff tracer is in use, stop tracing the interrupt disable
interval when returning to userspace. Tracing userspace execution time
as interrupts disabled time is not helpful for kernel performance
analysis purposes. Only do so if the irqsoff tracer is enabled, to
avoid overhead for lockdep, which doesn't care.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
---
arch/arm/kernel/entry-common.S | 6 ++++++
1 files changed, 6 insertions(+), 0 deletions(-)
diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S
index 8bfa987..80bf8cd 100644
--- a/arch/arm/kernel/entry-common.S
+++ b/arch/arm/kernel/entry-common.S
@@ -29,6 +29,9 @@ ret_fast_syscall:
ldr r1, [tsk, #TI_FLAGS]
tst r1, #_TIF_WORK_MASK
bne fast_work_pending
+#if defined(CONFIG_IRQSOFF_TRACER)
+ asm_trace_hardirqs_on
+#endif
/* perform architecture specific actions before user return */
arch_ret_to_user r1, lr
@@ -65,6 +68,9 @@ ret_slow_syscall:
tst r1, #_TIF_WORK_MASK
bne work_pending
no_work_pending:
+#if defined(CONFIG_IRQSOFF_TRACER)
+ asm_trace_hardirqs_on
+#endif
/* perform architecture specific actions before user return */
arch_ret_to_user r1, lr
--
1.6.6.1
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