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From: Boqun Feng <boqun.feng@gmail.com>
To: linux-kernel@vger.kernel.org
Cc: Ingo Molnar <mingo@redhat.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Gautham R Shenoy <ego@in.ibm.com>,
	Byungchul Park <byungchul.park@lge.com>,
	Boqun Feng <boqun.feng@gmail.com>
Subject: [RFC tip 2/5] lockdep/selftest: Add more recursive read related test cases
Date: Mon, 28 Aug 2017 22:56:54 +0800	[thread overview]
Message-ID: <20170828145657.11292-3-boqun.feng@gmail.com> (raw)
In-Reply-To: <20170828145657.11292-1-boqun.feng@gmail.com>

Add those four test cases:

1.
	CPU1		CPU2		CPU3
	=============	=============	=============
	write_lock(X);
			write_lock(Y);
					write_lock(Z);
	read_lock(Y);
			read_lock(Z);
					read_lock(X);

	deadlock.

2.
	CPU1		CPU2		CPU3
	=============	=============	=============
	write_lock(X);
			read_lock(Y);
					write_lock(Z);
	write_lock(Y);
			read_lock(Z);
					read_lock(X);

	deadlock.

3.
	CPU1		CPU2		CPU3
	=============	=============	=============
	write_lock(X);
			read_lock(Y);
					read_lock(Z);
	write_lock(Y);
			read_lock(Z);
					write_lock(X);

	not deadlock.

4.
	CPU1		CPU2		CPU3
	=============	=============	=============
	write_lock(X);
			read_lock(Y);
					write_lock(Z);
	read_lock(Y);
			read_lock(Z);
					write_lock(X);

	not deadlock.

Those self testcases are valuable for the development of supporting
recursive read related deadlock detection.

Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
---
 lib/locking-selftest.c | 161 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 161 insertions(+)

diff --git a/lib/locking-selftest.c b/lib/locking-selftest.c
index 747a5379aeee..9c04b304008a 100644
--- a/lib/locking-selftest.c
+++ b/lib/locking-selftest.c
@@ -1070,6 +1070,133 @@ GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_soft)
 #undef E2
 #undef E3
 
+/*
+ * write-read / write-read / write-read deadlock even if read is recursive
+ */
+
+#define E1()				\
+					\
+	WL(X1);				\
+	RL(Y1);				\
+	RU(Y1);				\
+	WU(X1);
+
+#define E2()				\
+					\
+	WL(Y1);				\
+	RL(Z1);				\
+	RU(Z1);				\
+	WU(Y1);
+
+#define E3()				\
+					\
+	WL(Z1);				\
+	RL(X1);				\
+	RU(X1);				\
+	WU(Z1);
+
+#include "locking-selftest-rlock.h"
+GENERATE_PERMUTATIONS_3_EVENTS(W1R2_W2R3_W3R1)
+
+#undef E1
+#undef E2
+#undef E3
+
+/*
+ * write-write / read-read / write-read deadlock even if read is recursive
+ */
+
+#define E1()				\
+					\
+	WL(X1);				\
+	WL(Y1);				\
+	WU(Y1);				\
+	WU(X1);
+
+#define E2()				\
+					\
+	RL(Y1);				\
+	RL(Z1);				\
+	RU(Z1);				\
+	RU(Y1);
+
+#define E3()				\
+					\
+	WL(Z1);				\
+	RL(X1);				\
+	RU(X1);				\
+	WU(Z1);
+
+#include "locking-selftest-rlock.h"
+GENERATE_PERMUTATIONS_3_EVENTS(W1W2_R2R3_W3R1)
+
+#undef E1
+#undef E2
+#undef E3
+
+/*
+ * write-write / read-read / read-write is not deadlock when read is recursive
+ */
+
+#define E1()				\
+					\
+	WL(X1);				\
+	WL(Y1);				\
+	WU(Y1);				\
+	WU(X1);
+
+#define E2()				\
+					\
+	RL(Y1);				\
+	RL(Z1);				\
+	RU(Z1);				\
+	RU(Y1);
+
+#define E3()				\
+					\
+	RL(Z1);				\
+	WL(X1);				\
+	WU(X1);				\
+	RU(Z1);
+
+#include "locking-selftest-rlock.h"
+GENERATE_PERMUTATIONS_3_EVENTS(W1R2_R2R3_W3W1)
+
+#undef E1
+#undef E2
+#undef E3
+
+/*
+ * write-read / read-read / write-write is not deadlock when read is recursive
+ */
+
+#define E1()				\
+					\
+	WL(X1);				\
+	RL(Y1);				\
+	RU(Y1);				\
+	WU(X1);
+
+#define E2()				\
+					\
+	RL(Y1);				\
+	RL(Z1);				\
+	RU(Z1);				\
+	RU(Y1);
+
+#define E3()				\
+					\
+	WL(Z1);				\
+	WL(X1);				\
+	WU(X1);				\
+	WU(Z1);
+
+#include "locking-selftest-rlock.h"
+GENERATE_PERMUTATIONS_3_EVENTS(W1W2_R2R3_R3W1)
+
+#undef E1
+#undef E2
+#undef E3
 /*
  * read-lock / write-lock recursion that is unsafe.
  */
@@ -1241,6 +1368,19 @@ static inline void print_testname(const char *testname)
 	dotest(name##_##nr, FAILURE, LOCKTYPE_RWLOCK);		\
 	pr_cont("\n");
 
+#define DO_TESTCASE_1RR(desc, name, nr)				\
+	print_testname(desc"/"#nr);				\
+	pr_cont("             |");				\
+	dotest(name##_##nr, SUCCESS, LOCKTYPE_RWLOCK);		\
+	pr_cont("\n");
+
+#define DO_TESTCASE_1RRB(desc, name, nr)			\
+	print_testname(desc"/"#nr);				\
+	pr_cont("             |");				\
+	dotest(name##_##nr, FAILURE, LOCKTYPE_RWLOCK);		\
+	pr_cont("\n");
+
+
 #define DO_TESTCASE_3(desc, name, nr)				\
 	print_testname(desc"/"#nr);				\
 	dotest(name##_spin_##nr, FAILURE, LOCKTYPE_SPIN);	\
@@ -1331,6 +1471,22 @@ static inline void print_testname(const char *testname)
 	DO_TESTCASE_2IB(desc, name, 312);			\
 	DO_TESTCASE_2IB(desc, name, 321);
 
+#define DO_TESTCASE_6x1RR(desc, name)				\
+	DO_TESTCASE_1RR(desc, name, 123);			\
+	DO_TESTCASE_1RR(desc, name, 132);			\
+	DO_TESTCASE_1RR(desc, name, 213);			\
+	DO_TESTCASE_1RR(desc, name, 231);			\
+	DO_TESTCASE_1RR(desc, name, 312);			\
+	DO_TESTCASE_1RR(desc, name, 321);
+
+#define DO_TESTCASE_6x1RRB(desc, name)				\
+	DO_TESTCASE_1RRB(desc, name, 123);			\
+	DO_TESTCASE_1RRB(desc, name, 132);			\
+	DO_TESTCASE_1RRB(desc, name, 213);			\
+	DO_TESTCASE_1RRB(desc, name, 231);			\
+	DO_TESTCASE_1RRB(desc, name, 312);			\
+	DO_TESTCASE_1RRB(desc, name, 321);
+
 #define DO_TESTCASE_6x6(desc, name)				\
 	DO_TESTCASE_6I(desc, name, 123);			\
 	DO_TESTCASE_6I(desc, name, 132);			\
@@ -2093,6 +2249,11 @@ void locking_selftest(void)
 	pr_cont("             |");
 	dotest(rlock_chaincache_ABBA1, FAILURE, LOCKTYPE_RWLOCK);
 
+	DO_TESTCASE_6x1RRB("rlock W1R2/W2R3/W3R1", W1R2_W2R3_W3R1);
+	DO_TESTCASE_6x1RRB("rlock W1W2/R2R3/W3R1", W1W2_R2R3_W3R1);
+	DO_TESTCASE_6x1RR("rlock W1W2/R2R3/R3W1", W1W2_R2R3_R3W1);
+	DO_TESTCASE_6x1RR("rlock W1R2/R2R3/W3W1", W1R2_R2R3_W3W1);
+
 	printk("  --------------------------------------------------------------------------\n");
 
 	/*
-- 
2.14.1

  parent reply	other threads:[~2017-08-28 14:57 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-08-28 14:56 [RFC tip 0/5] lockdep: Support deadlock detection for recursive read locks Boqun Feng
2017-08-28 14:56 ` [RFC tip 1/5] lockdep/selftest: Add a R-L/L-W test case specific to chain cache behavior Boqun Feng
2017-08-28 14:56 ` Boqun Feng [this message]
2017-08-28 14:56 ` [RFC tip 3/5] lockdep: Demagic the return value of BFS Boqun Feng
2017-08-28 14:56 ` [RFC tip 4/5] lockdep: Support deadlock detection for recursive read locks in check_noncircular() Boqun Feng
2017-08-28 14:56 ` [RFC tip 5/5] lockdep: Take read/write status in consideration when generate chainkey Boqun Feng

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