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From:   Boqun Feng <boqun.feng@gmail.com>
To:     linux-kernel@vger.kernel.org
Cc:     Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>, Will Deacon <will@kernel.org>,
        Waiman Long <longman@redhat.com>,
        Boqun Feng <boqun.feng@gmail.com>
Subject: [PATCH] lockdep/selftests: Use SBRM APIs for wait context tests
Date:   Sat, 15 Jul 2023 16:52:57 -0700
Message-ID: <20230715235257.110325-1-boqun.feng@gmail.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

The "__cleanup__" attribute is already used for wait context tests, so
using it for locking tests has already been proven working. Now since
SBRM APIs are merged, let's use these APIs instead of a local guard
framework. This also helps testing SBRM APIs.

Note that originally the tests don't rely on the cleanup ordering of
two variables in the same scope, but since now it's something we'd like
to assume and rely on[1], drop the extra scope in inner_in_outer()
function. Again this gives us another opportunity to test the compiler
behavior.

[1]: https://lore.kernel.org/lkml/CAHk-=whEsr6fuVSdsoNPokLR2fZiGuo_hCLyrS-LCw7hT_N7cQ@mail.gmail.com/
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
---
 lib/locking-selftest.c | 135 +++++++++++------------------------------
 1 file changed, 35 insertions(+), 100 deletions(-)

diff --git a/lib/locking-selftest.c b/lib/locking-selftest.c
index 8d24279fad05..6f6a5fc85b42 100644
--- a/lib/locking-selftest.c
+++ b/lib/locking-selftest.c
@@ -2506,94 +2506,29 @@ static void fs_reclaim_tests(void)
 	pr_cont("\n");
 }
 
-#define __guard(cleanup) __maybe_unused __attribute__((__cleanup__(cleanup)))
+/* Defines guard classes to create contexts */
+DEFINE_LOCK_GUARD_0(HARDIRQ, HARDIRQ_ENTER(), HARDIRQ_EXIT())
+DEFINE_LOCK_GUARD_0(NOTTHREADED_HARDIRQ,
+	do {
+		local_irq_disable();
+		__irq_enter();
+		WARN_ON(!in_irq());
+	} while(0), HARDIRQ_EXIT())
+DEFINE_LOCK_GUARD_0(SOFTIRQ, SOFTIRQ_ENTER(), SOFTIRQ_EXIT())
+
+/* Define RCU guards, should go away when RCU has its own guard definitions */
+DEFINE_LOCK_GUARD_0(RCU, rcu_read_lock(), rcu_read_unlock())
+DEFINE_LOCK_GUARD_0(RCU_BH, rcu_read_lock_bh(), rcu_read_unlock_bh())
+DEFINE_LOCK_GUARD_0(RCU_SCHED, rcu_read_lock_sched(), rcu_read_unlock_sched())
 
-static void hardirq_exit(int *_)
-{
-	HARDIRQ_EXIT();
-}
-
-#define HARDIRQ_CONTEXT(name, ...)					\
-	int hardirq_guard_##name __guard(hardirq_exit);			\
-	HARDIRQ_ENTER();
-
-#define NOTTHREADED_HARDIRQ_CONTEXT(name, ...)				\
-	int notthreaded_hardirq_guard_##name __guard(hardirq_exit);	\
-	local_irq_disable();						\
-	__irq_enter();							\
-	WARN_ON(!in_irq());
-
-static void softirq_exit(int *_)
-{
-	SOFTIRQ_EXIT();
-}
-
-#define SOFTIRQ_CONTEXT(name, ...)				\
-	int softirq_guard_##name __guard(softirq_exit);		\
-	SOFTIRQ_ENTER();
-
-static void rcu_exit(int *_)
-{
-	rcu_read_unlock();
-}
-
-#define RCU_CONTEXT(name, ...)					\
-	int rcu_guard_##name __guard(rcu_exit);			\
-	rcu_read_lock();
-
-static void rcu_bh_exit(int *_)
-{
-	rcu_read_unlock_bh();
-}
-
-#define RCU_BH_CONTEXT(name, ...)				\
-	int rcu_bh_guard_##name __guard(rcu_bh_exit);		\
-	rcu_read_lock_bh();
-
-static void rcu_sched_exit(int *_)
-{
-	rcu_read_unlock_sched();
-}
-
-#define RCU_SCHED_CONTEXT(name, ...)				\
-	int rcu_sched_guard_##name __guard(rcu_sched_exit);	\
-	rcu_read_lock_sched();
-
-static void raw_spinlock_exit(raw_spinlock_t **lock)
-{
-	raw_spin_unlock(*lock);
-}
-
-#define RAW_SPINLOCK_CONTEXT(name, lock)						\
-	raw_spinlock_t *raw_spinlock_guard_##name __guard(raw_spinlock_exit) = &(lock);	\
-	raw_spin_lock(&(lock));
-
-static void spinlock_exit(spinlock_t **lock)
-{
-	spin_unlock(*lock);
-}
-
-#define SPINLOCK_CONTEXT(name, lock)						\
-	spinlock_t *spinlock_guard_##name __guard(spinlock_exit) = &(lock);	\
-	spin_lock(&(lock));
-
-static void mutex_exit(struct mutex **lock)
-{
-	mutex_unlock(*lock);
-}
-
-#define MUTEX_CONTEXT(name, lock)					\
-	struct mutex *mutex_guard_##name __guard(mutex_exit) = &(lock);	\
-	mutex_lock(&(lock));
 
 #define GENERATE_2_CONTEXT_TESTCASE(outer, outer_lock, inner, inner_lock)	\
 										\
 static void __maybe_unused inner##_in_##outer(void)				\
 {										\
-	outer##_CONTEXT(_, outer_lock);						\
-	{									\
-		inner##_CONTEXT(_, inner_lock);					\
-	}									\
+	/* Relies the reversed clean-up ordering: inner first */		\
+	guard(outer)(outer_lock);						\
+	guard(inner)(inner_lock);						\
 }
 
 /*
@@ -2632,21 +2567,21 @@ GENERATE_2_CONTEXT_TESTCASE(SOFTIRQ, , inner, inner_lock)			\
 GENERATE_2_CONTEXT_TESTCASE(RCU, , inner, inner_lock)				\
 GENERATE_2_CONTEXT_TESTCASE(RCU_BH, , inner, inner_lock)			\
 GENERATE_2_CONTEXT_TESTCASE(RCU_SCHED, , inner, inner_lock)			\
-GENERATE_2_CONTEXT_TESTCASE(RAW_SPINLOCK, raw_lock_A, inner, inner_lock)	\
-GENERATE_2_CONTEXT_TESTCASE(SPINLOCK, lock_A, inner, inner_lock)		\
-GENERATE_2_CONTEXT_TESTCASE(MUTEX, mutex_A, inner, inner_lock)
+GENERATE_2_CONTEXT_TESTCASE(raw_spinlock, &raw_lock_A, inner, inner_lock)	\
+GENERATE_2_CONTEXT_TESTCASE(spinlock, &lock_A, inner, inner_lock)		\
+GENERATE_2_CONTEXT_TESTCASE(mutex, &mutex_A, inner, inner_lock)
 
 GENERATE_2_CONTEXT_TESTCASE_FOR_ALL_OUTER(RCU, )
-GENERATE_2_CONTEXT_TESTCASE_FOR_ALL_OUTER(RAW_SPINLOCK, raw_lock_B)
-GENERATE_2_CONTEXT_TESTCASE_FOR_ALL_OUTER(SPINLOCK, lock_B)
-GENERATE_2_CONTEXT_TESTCASE_FOR_ALL_OUTER(MUTEX, mutex_B)
+GENERATE_2_CONTEXT_TESTCASE_FOR_ALL_OUTER(raw_spinlock, &raw_lock_B)
+GENERATE_2_CONTEXT_TESTCASE_FOR_ALL_OUTER(spinlock, &lock_B)
+GENERATE_2_CONTEXT_TESTCASE_FOR_ALL_OUTER(mutex, &mutex_B)
 
 /* the outer context allows all kinds of preemption */
 #define DO_CONTEXT_TESTCASE_OUTER_PREEMPTIBLE(outer)			\
 	dotest(RCU_in_##outer, SUCCESS, LOCKTYPE_RWLOCK);		\
-	dotest(RAW_SPINLOCK_in_##outer, SUCCESS, LOCKTYPE_SPIN);	\
-	dotest(SPINLOCK_in_##outer, SUCCESS, LOCKTYPE_SPIN);		\
-	dotest(MUTEX_in_##outer, SUCCESS, LOCKTYPE_MUTEX);		\
+	dotest(raw_spinlock_in_##outer, SUCCESS, LOCKTYPE_SPIN);	\
+	dotest(spinlock_in_##outer, SUCCESS, LOCKTYPE_SPIN);		\
+	dotest(mutex_in_##outer, SUCCESS, LOCKTYPE_MUTEX);		\
 
 /*
  * the outer context only allows the preemption introduced by spinlock_t (which
@@ -2654,16 +2589,16 @@ GENERATE_2_CONTEXT_TESTCASE_FOR_ALL_OUTER(MUTEX, mutex_B)
  */
 #define DO_CONTEXT_TESTCASE_OUTER_LIMITED_PREEMPTIBLE(outer)		\
 	dotest(RCU_in_##outer, SUCCESS, LOCKTYPE_RWLOCK);		\
-	dotest(RAW_SPINLOCK_in_##outer, SUCCESS, LOCKTYPE_SPIN);	\
-	dotest(SPINLOCK_in_##outer, SUCCESS, LOCKTYPE_SPIN);		\
-	dotest(MUTEX_in_##outer, FAILURE, LOCKTYPE_MUTEX);		\
+	dotest(raw_spinlock_in_##outer, SUCCESS, LOCKTYPE_SPIN);	\
+	dotest(spinlock_in_##outer, SUCCESS, LOCKTYPE_SPIN);		\
+	dotest(mutex_in_##outer, FAILURE, LOCKTYPE_MUTEX);		\
 
 /* the outer doesn't allows any kind of preemption */
 #define DO_CONTEXT_TESTCASE_OUTER_NOT_PREEMPTIBLE(outer)			\
 	dotest(RCU_in_##outer, SUCCESS, LOCKTYPE_RWLOCK);		\
-	dotest(RAW_SPINLOCK_in_##outer, SUCCESS, LOCKTYPE_SPIN);	\
-	dotest(SPINLOCK_in_##outer, FAILURE, LOCKTYPE_SPIN);		\
-	dotest(MUTEX_in_##outer, FAILURE, LOCKTYPE_MUTEX);		\
+	dotest(raw_spinlock_in_##outer, SUCCESS, LOCKTYPE_SPIN);	\
+	dotest(spinlock_in_##outer, FAILURE, LOCKTYPE_SPIN);		\
+	dotest(mutex_in_##outer, FAILURE, LOCKTYPE_MUTEX);		\
 
 static void wait_context_tests(void)
 {
@@ -2697,15 +2632,15 @@ static void wait_context_tests(void)
 	pr_cont("\n");
 
 	print_testname("in RAW_SPINLOCK context");
-	DO_CONTEXT_TESTCASE_OUTER_NOT_PREEMPTIBLE(RAW_SPINLOCK);
+	DO_CONTEXT_TESTCASE_OUTER_NOT_PREEMPTIBLE(raw_spinlock);
 	pr_cont("\n");
 
 	print_testname("in SPINLOCK context");
-	DO_CONTEXT_TESTCASE_OUTER_LIMITED_PREEMPTIBLE(SPINLOCK);
+	DO_CONTEXT_TESTCASE_OUTER_LIMITED_PREEMPTIBLE(spinlock);
 	pr_cont("\n");
 
 	print_testname("in MUTEX context");
-	DO_CONTEXT_TESTCASE_OUTER_PREEMPTIBLE(MUTEX);
+	DO_CONTEXT_TESTCASE_OUTER_PREEMPTIBLE(mutex);
 	pr_cont("\n");
 }
 
-- 
2.41.0