[PATCH 2/2] lockdep: allow user to disable CONFIG_TRACE_IRQFLAGS

From: Ming Lei <tom.leiming@gmail.com>

There is still the lost irq-on tracing issue on ARM,
(see http://marc.info/?l=linux-arm-kernel&m=126047420005553&w=2)
which may disable lockdep after kernel boot, seems no
good solution for the issue up to now.

The patch exports the config option of CONFIG_TRACE_IRQFLAGS
and allows user to disable it for support of checking circular
dead lock only if irq flags tracing can't work correctly always.

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
---
?lib/Kconfig.debug ? ? ?| ? ?3 +++
?lib/locking-selftest.c | ? ?2 ++
?2 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 935248b..448f18f 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug

@@ -550,11 +550,14 @@ config DEBUG_LOCKDEP

? ? ? ? ?of more runtime overhead.

?config TRACE_IRQFLAGS
+ ? ? ? bool "Lock prove: IRQ flags tracing"
? ? ? ?depends on DEBUG_KERNEL
? ? ? ?bool
? ? ? ?default y
? ? ? ?depends on TRACE_IRQFLAGS_SUPPORT
? ? ? ?depends on PROVE_LOCKING
+ ? ? ? help
+ ? ? ? ? If you say Y here, IRQ flags will be traced to prove locking.

?config DEBUG_SPINLOCK_SLEEP
? ? ? ?bool "Spinlock debugging: sleep-inside-spinlock checking"

diff --git a/lib/locking-selftest.c b/lib/locking-selftest.c
index 619313e..d9e5bfe 100644
--- a/lib/locking-selftest.c
+++ b/lib/locking-selftest.c

@@ -1176,6 +1176,7 @@ void locking_selftest(void)

? ? ? ?printk(" ?--------------------------------------------------------------------------\n");

+#ifdef CONFIG_TRACE_IRQFLAGS
? ? ? ?/*
? ? ? ? * irq-context testcases:
? ? ? ? */

@@ -1188,6 +1189,7 @@ void locking_selftest(void)

? ? ? ?DO_TESTCASE_6x2("irq read-recursion", irq_read_recursion);
?// ? ? DO_TESTCASE_6x2B("irq read-recursion #2", irq_read_recursion2);
+#endif

? ? ? ?if (unexpected_testcase_failures) {
? ? ? ? ? ? ? ?printk("-----------------------------------------------------------------\n");
--
1.6.2.5