The following commit has been merged into the locking/core branch of tip:
Commit-ID: 7e923e6a3ceb877497dd9ee70d71fa33b94f332b
Gitweb:
https://git.kernel.org/tip/7e923e6a3ceb877497dd9ee70d71fa33b94f332b
Author: Peter Zijlstra <pet...@infradead.org>
AuthorDate: Wed, 09 Dec 2020 16:06:06 +01:00
Committer: Peter Zijlstra <pet...@infradead.org>
CommitterDate: Thu, 14 Jan 2021 11:20:18 +01:00
locking/selftests: Add local_lock inversion tests
Test the local_lock_t inversion scenarios.
Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org>
---
lib/locking-selftest.c | 97 +++++++++++++++++++++++++++++++++++++++++-
1 file changed, 97 insertions(+)
diff --git a/lib/locking-selftest.c b/lib/locking-selftest.c
index 3306f43..2d85aba 100644
--- a/lib/locking-selftest.c
+++ b/lib/locking-selftest.c
@@ -24,6 +24,7 @@
#include <linux/debug_locks.h>
#include <linux/irqflags.h>
#include <linux/rtmutex.h>
+#include <linux/local_lock.h>
/*
* Change this to 1 if you want to see the failure printouts:
@@ -51,6 +52,7 @@ __setup("debug_locks_verbose=", setup_debug_locks_verbose);
#define LOCKTYPE_RWSEM 0x8
#define LOCKTYPE_WW 0x10
#define LOCKTYPE_RTMUTEX 0x20
+#define LOCKTYPE_LL 0x40
static struct ww_acquire_ctx t, t2;
static struct ww_mutex o, o2, o3;
@@ -136,6 +138,8 @@ static DEFINE_RT_MUTEX(rtmutex_Z2);
#endif
+static local_lock_t local_A = INIT_LOCAL_LOCK(local_A);
+
/*
* non-inlined runtime initializers, to let separate locks share
* the same lock-class:
@@ -1314,6 +1318,7 @@
GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion3_soft_wlock)
# define I_MUTEX(x) lockdep_reset_lock(&mutex_##x.dep_map)
# define I_RWSEM(x) lockdep_reset_lock(&rwsem_##x.dep_map)
# define I_WW(x) lockdep_reset_lock(&x.dep_map)
+# define I_LOCAL_LOCK(x) lockdep_reset_lock(&local_##x.dep_map)
#ifdef CONFIG_RT_MUTEXES
# define I_RTMUTEX(x) lockdep_reset_lock(&rtmutex_##x.dep_map)
#endif
@@ -1324,6 +1329,7 @@
GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion3_soft_wlock)
# define I_MUTEX(x)
# define I_RWSEM(x)
# define I_WW(x)
+# define I_LOCAL_LOCK(x)
#endif
#ifndef I_RTMUTEX
@@ -1364,11 +1370,15 @@ static void reset_locks(void)
I1(X1); I1(X2); I1(Y1); I1(Y2); I1(Z1); I1(Z2);
I_WW(t); I_WW(t2); I_WW(o.base); I_WW(o2.base); I_WW(o3.base);
I_RAW_SPINLOCK(A); I_RAW_SPINLOCK(B);
+ I_LOCAL_LOCK(A);
+
lockdep_reset();
+
I2(A); I2(B); I2(C); I2(D);
init_shared_classes();
raw_spin_lock_init(&raw_lock_A);
raw_spin_lock_init(&raw_lock_B);
+ local_lock_init(&local_A);
ww_mutex_init(&o, &ww_lockdep); ww_mutex_init(&o2, &ww_lockdep);
ww_mutex_init(&o3, &ww_lockdep);
memset(&t, 0, sizeof(t)); memset(&t2, 0, sizeof(t2));
@@ -2649,6 +2659,91 @@ static void wait_context_tests(void)
pr_cont("\n");
}
+static void local_lock_2(void)
+{
+ local_lock_acquire(&local_A); /* IRQ-ON */
+ local_lock_release(&local_A);
+
+ HARDIRQ_ENTER();
+ spin_lock(&lock_A); /* IN-IRQ */
+ spin_unlock(&lock_A);
+ HARDIRQ_EXIT()
+
+ HARDIRQ_DISABLE();
+ spin_lock(&lock_A);
+ local_lock_acquire(&local_A); /* IN-IRQ <-> IRQ-ON cycle, false */
+ local_lock_release(&local_A);
+ spin_unlock(&lock_A);
+ HARDIRQ_ENABLE();
+}
+
+static void local_lock_3A(void)
+{
+ local_lock_acquire(&local_A); /* IRQ-ON */
+ spin_lock(&lock_B); /* IRQ-ON */
+ spin_unlock(&lock_B);
+ local_lock_release(&local_A);
+
+ HARDIRQ_ENTER();
+ spin_lock(&lock_A); /* IN-IRQ */
+ spin_unlock(&lock_A);
+ HARDIRQ_EXIT()
+
+ HARDIRQ_DISABLE();
+ spin_lock(&lock_A);
+ local_lock_acquire(&local_A); /* IN-IRQ <-> IRQ-ON cycle only if we
count local_lock(), false */
+ local_lock_release(&local_A);
+ spin_unlock(&lock_A);
+ HARDIRQ_ENABLE();
+}
+
+static void local_lock_3B(void)
+{
+ local_lock_acquire(&local_A); /* IRQ-ON */
+ spin_lock(&lock_B); /* IRQ-ON */
+ spin_unlock(&lock_B);
+ local_lock_release(&local_A);
+
+ HARDIRQ_ENTER();
+ spin_lock(&lock_A); /* IN-IRQ */
+ spin_unlock(&lock_A);
+ HARDIRQ_EXIT()
+
+ HARDIRQ_DISABLE();
+ spin_lock(&lock_A);
+ local_lock_acquire(&local_A); /* IN-IRQ <-> IRQ-ON cycle only if we
count local_lock(), false */
+ local_lock_release(&local_A);
+ spin_unlock(&lock_A);
+ HARDIRQ_ENABLE();
+
+ HARDIRQ_DISABLE();
+ spin_lock(&lock_A);
+ spin_lock(&lock_B); /* IN-IRQ <-> IRQ-ON cycle, true */
+ spin_unlock(&lock_B);
+ spin_unlock(&lock_A);
+ HARDIRQ_DISABLE();
+
+}
+
+static void local_lock_tests(void)
+{
+ printk("
--------------------------------------------------------------------------\n");
+ printk(" | local_lock tests |\n");
+ printk(" ---------------------\n");
+
+ print_testname("local_lock inversion 2");
+ dotest(local_lock_2, SUCCESS, LOCKTYPE_LL);
+ pr_cont("\n");
+
+ print_testname("local_lock inversion 3A");
+ dotest(local_lock_3A, SUCCESS, LOCKTYPE_LL);
+ pr_cont("\n");
+
+ print_testname("local_lock inversion 3B");
+ dotest(local_lock_3B, FAILURE, LOCKTYPE_LL);
+ pr_cont("\n");
+}
+
void locking_selftest(void)
{
/*
@@ -2775,6 +2870,8 @@ void locking_selftest(void)
if (IS_ENABLED(CONFIG_PROVE_RAW_LOCK_NESTING))
wait_context_tests();
+ local_lock_tests();
+
if (unexpected_testcase_failures) {
printk("-----------------------------------------------------------------\n");
debug_locks = 0;
