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-rw-r--r--kernel/locking/lockdep.c86
-rw-r--r--kernel/locking/locktorture.c24
-rw-r--r--kernel/locking/osq_lock.c6
-rw-r--r--kernel/locking/qspinlock.c7
4 files changed, 67 insertions, 56 deletions
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index c9ea05edce25..2fad21d345b0 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -1723,7 +1723,7 @@ static int noop_count(struct lock_list *entry, void *data)
static unsigned long __lockdep_count_forward_deps(struct lock_list *this)
{
unsigned long count = 0;
- struct lock_list *uninitialized_var(target_entry);
+ struct lock_list *target_entry;
__bfs_forwards(this, (void *)&count, noop_count, &target_entry);
@@ -1749,7 +1749,7 @@ unsigned long lockdep_count_forward_deps(struct lock_class *class)
static unsigned long __lockdep_count_backward_deps(struct lock_list *this)
{
unsigned long count = 0;
- struct lock_list *uninitialized_var(target_entry);
+ struct lock_list *target_entry;
__bfs_backwards(this, (void *)&count, noop_count, &target_entry);
@@ -1804,7 +1804,7 @@ check_noncircular(struct held_lock *src, struct held_lock *target,
struct lock_trace **const trace)
{
int ret;
- struct lock_list *uninitialized_var(target_entry);
+ struct lock_list *target_entry;
struct lock_list src_entry = {
.class = hlock_class(src),
.parent = NULL,
@@ -1842,7 +1842,7 @@ static noinline int
check_redundant(struct held_lock *src, struct held_lock *target)
{
int ret;
- struct lock_list *uninitialized_var(target_entry);
+ struct lock_list *target_entry;
struct lock_list src_entry = {
.class = hlock_class(src),
.parent = NULL,
@@ -2244,8 +2244,8 @@ static int check_irq_usage(struct task_struct *curr, struct held_lock *prev,
{
unsigned long usage_mask = 0, forward_mask, backward_mask;
enum lock_usage_bit forward_bit = 0, backward_bit = 0;
- struct lock_list *uninitialized_var(target_entry1);
- struct lock_list *uninitialized_var(target_entry);
+ struct lock_list *target_entry1;
+ struct lock_list *target_entry;
struct lock_list this, that;
int ret;
@@ -3438,7 +3438,7 @@ check_usage_forwards(struct task_struct *curr, struct held_lock *this,
{
int ret;
struct lock_list root;
- struct lock_list *uninitialized_var(target_entry);
+ struct lock_list *target_entry;
root.parent = NULL;
root.class = hlock_class(this);
@@ -3465,7 +3465,7 @@ check_usage_backwards(struct task_struct *curr, struct held_lock *this,
{
int ret;
struct lock_list root;
- struct lock_list *uninitialized_var(target_entry);
+ struct lock_list *target_entry;
root.parent = NULL;
root.class = hlock_class(this);
@@ -3484,19 +3484,21 @@ check_usage_backwards(struct task_struct *curr, struct held_lock *this,
void print_irqtrace_events(struct task_struct *curr)
{
- printk("irq event stamp: %u\n", curr->irq_events);
+ const struct irqtrace_events *trace = &curr->irqtrace;
+
+ printk("irq event stamp: %u\n", trace->irq_events);
printk("hardirqs last enabled at (%u): [<%px>] %pS\n",
- curr->hardirq_enable_event, (void *)curr->hardirq_enable_ip,
- (void *)curr->hardirq_enable_ip);
+ trace->hardirq_enable_event, (void *)trace->hardirq_enable_ip,
+ (void *)trace->hardirq_enable_ip);
printk("hardirqs last disabled at (%u): [<%px>] %pS\n",
- curr->hardirq_disable_event, (void *)curr->hardirq_disable_ip,
- (void *)curr->hardirq_disable_ip);
+ trace->hardirq_disable_event, (void *)trace->hardirq_disable_ip,
+ (void *)trace->hardirq_disable_ip);
printk("softirqs last enabled at (%u): [<%px>] %pS\n",
- curr->softirq_enable_event, (void *)curr->softirq_enable_ip,
- (void *)curr->softirq_enable_ip);
+ trace->softirq_enable_event, (void *)trace->softirq_enable_ip,
+ (void *)trace->softirq_enable_ip);
printk("softirqs last disabled at (%u): [<%px>] %pS\n",
- curr->softirq_disable_event, (void *)curr->softirq_disable_ip,
- (void *)curr->softirq_disable_ip);
+ trace->softirq_disable_event, (void *)trace->softirq_disable_ip,
+ (void *)trace->softirq_disable_ip);
}
static int HARDIRQ_verbose(struct lock_class *class)
@@ -3699,7 +3701,7 @@ EXPORT_SYMBOL_GPL(lockdep_hardirqs_on_prepare);
void noinstr lockdep_hardirqs_on(unsigned long ip)
{
- struct task_struct *curr = current;
+ struct irqtrace_events *trace = &current->irqtrace;
if (unlikely(!debug_locks))
return;
@@ -3712,6 +3714,9 @@ void noinstr lockdep_hardirqs_on(unsigned long ip)
* and not rely on hardware state like normal interrupts.
*/
if (unlikely(in_nmi())) {
+ if (!IS_ENABLED(CONFIG_TRACE_IRQFLAGS_NMI))
+ return;
+
/*
* Skip:
* - recursion check, because NMI can hit lockdep;
@@ -3752,8 +3757,8 @@ void noinstr lockdep_hardirqs_on(unsigned long ip)
skip_checks:
/* we'll do an OFF -> ON transition: */
this_cpu_write(hardirqs_enabled, 1);
- curr->hardirq_enable_ip = ip;
- curr->hardirq_enable_event = ++curr->irq_events;
+ trace->hardirq_enable_ip = ip;
+ trace->hardirq_enable_event = ++trace->irq_events;
debug_atomic_inc(hardirqs_on_events);
}
EXPORT_SYMBOL_GPL(lockdep_hardirqs_on);
@@ -3763,8 +3768,6 @@ EXPORT_SYMBOL_GPL(lockdep_hardirqs_on);
*/
void noinstr lockdep_hardirqs_off(unsigned long ip)
{
- struct task_struct *curr = current;
-
if (unlikely(!debug_locks))
return;
@@ -3773,7 +3776,10 @@ void noinstr lockdep_hardirqs_off(unsigned long ip)
* they will restore the software state. This ensures the software
* state is consistent inside NMIs as well.
*/
- if (unlikely(!in_nmi() && (current->lockdep_recursion & LOCKDEP_RECURSION_MASK)))
+ if (in_nmi()) {
+ if (!IS_ENABLED(CONFIG_TRACE_IRQFLAGS_NMI))
+ return;
+ } else if (current->lockdep_recursion & LOCKDEP_RECURSION_MASK)
return;
/*
@@ -3784,12 +3790,14 @@ void noinstr lockdep_hardirqs_off(unsigned long ip)
return;
if (lockdep_hardirqs_enabled()) {
+ struct irqtrace_events *trace = &current->irqtrace;
+
/*
* We have done an ON -> OFF transition:
*/
this_cpu_write(hardirqs_enabled, 0);
- curr->hardirq_disable_ip = ip;
- curr->hardirq_disable_event = ++curr->irq_events;
+ trace->hardirq_disable_ip = ip;
+ trace->hardirq_disable_event = ++trace->irq_events;
debug_atomic_inc(hardirqs_off_events);
} else {
debug_atomic_inc(redundant_hardirqs_off);
@@ -3802,7 +3810,7 @@ EXPORT_SYMBOL_GPL(lockdep_hardirqs_off);
*/
void lockdep_softirqs_on(unsigned long ip)
{
- struct task_struct *curr = current;
+ struct irqtrace_events *trace = &current->irqtrace;
if (unlikely(!debug_locks || current->lockdep_recursion))
return;
@@ -3814,7 +3822,7 @@ void lockdep_softirqs_on(unsigned long ip)
if (DEBUG_LOCKS_WARN_ON(!irqs_disabled()))
return;
- if (curr->softirqs_enabled) {
+ if (current->softirqs_enabled) {
debug_atomic_inc(redundant_softirqs_on);
return;
}
@@ -3823,9 +3831,9 @@ void lockdep_softirqs_on(unsigned long ip)
/*
* We'll do an OFF -> ON transition:
*/
- curr->softirqs_enabled = 1;
- curr->softirq_enable_ip = ip;
- curr->softirq_enable_event = ++curr->irq_events;
+ current->softirqs_enabled = 1;
+ trace->softirq_enable_ip = ip;
+ trace->softirq_enable_event = ++trace->irq_events;
debug_atomic_inc(softirqs_on_events);
/*
* We are going to turn softirqs on, so set the
@@ -3833,7 +3841,7 @@ void lockdep_softirqs_on(unsigned long ip)
* enabled too:
*/
if (lockdep_hardirqs_enabled())
- mark_held_locks(curr, LOCK_ENABLED_SOFTIRQ);
+ mark_held_locks(current, LOCK_ENABLED_SOFTIRQ);
lockdep_recursion_finish();
}
@@ -3842,8 +3850,6 @@ void lockdep_softirqs_on(unsigned long ip)
*/
void lockdep_softirqs_off(unsigned long ip)
{
- struct task_struct *curr = current;
-
if (unlikely(!debug_locks || current->lockdep_recursion))
return;
@@ -3853,13 +3859,15 @@ void lockdep_softirqs_off(unsigned long ip)
if (DEBUG_LOCKS_WARN_ON(!irqs_disabled()))
return;
- if (curr->softirqs_enabled) {
+ if (current->softirqs_enabled) {
+ struct irqtrace_events *trace = &current->irqtrace;
+
/*
* We have done an ON -> OFF transition:
*/
- curr->softirqs_enabled = 0;
- curr->softirq_disable_ip = ip;
- curr->softirq_disable_event = ++curr->irq_events;
+ current->softirqs_enabled = 0;
+ trace->softirq_disable_ip = ip;
+ trace->softirq_disable_event = ++trace->irq_events;
debug_atomic_inc(softirqs_off_events);
/*
* Whoops, we wanted softirqs off, so why aren't they?
@@ -5889,9 +5897,7 @@ void lockdep_rcu_suspicious(const char *file, const int line, const char *s)
pr_warn("\n%srcu_scheduler_active = %d, debug_locks = %d\n",
!rcu_lockdep_current_cpu_online()
? "RCU used illegally from offline CPU!\n"
- : !rcu_is_watching()
- ? "RCU used illegally from idle CPU!\n"
- : "",
+ : "",
rcu_scheduler_active, debug_locks);
/*
diff --git a/kernel/locking/locktorture.c b/kernel/locking/locktorture.c
index 5efbfc68ce99..9cfa5e89cff7 100644
--- a/kernel/locking/locktorture.c
+++ b/kernel/locking/locktorture.c
@@ -436,8 +436,6 @@ static int torture_rtmutex_lock(void) __acquires(torture_rtmutex)
static void torture_rtmutex_boost(struct torture_random_state *trsp)
{
- int policy;
- struct sched_param param;
const unsigned int factor = 50000; /* yes, quite arbitrary */
if (!rt_task(current)) {
@@ -448,8 +446,7 @@ static void torture_rtmutex_boost(struct torture_random_state *trsp)
*/
if (trsp && !(torture_random(trsp) %
(cxt.nrealwriters_stress * factor))) {
- policy = SCHED_FIFO;
- param.sched_priority = MAX_RT_PRIO - 1;
+ sched_set_fifo(current);
} else /* common case, do nothing */
return;
} else {
@@ -462,13 +459,10 @@ static void torture_rtmutex_boost(struct torture_random_state *trsp)
*/
if (!trsp || !(torture_random(trsp) %
(cxt.nrealwriters_stress * factor * 2))) {
- policy = SCHED_NORMAL;
- param.sched_priority = 0;
+ sched_set_normal(current, 0);
} else /* common case, do nothing */
return;
}
-
- sched_setscheduler_nocheck(current, policy, &param);
}
static void torture_rtmutex_delay(struct torture_random_state *trsp)
@@ -631,13 +625,13 @@ static int lock_torture_writer(void *arg)
cxt.cur_ops->writelock();
if (WARN_ON_ONCE(lock_is_write_held))
lwsp->n_lock_fail++;
- lock_is_write_held = 1;
+ lock_is_write_held = true;
if (WARN_ON_ONCE(lock_is_read_held))
lwsp->n_lock_fail++; /* rare, but... */
lwsp->n_lock_acquired++;
cxt.cur_ops->write_delay(&rand);
- lock_is_write_held = 0;
+ lock_is_write_held = false;
cxt.cur_ops->writeunlock();
stutter_wait("lock_torture_writer");
@@ -665,13 +659,13 @@ static int lock_torture_reader(void *arg)
schedule_timeout_uninterruptible(1);
cxt.cur_ops->readlock();
- lock_is_read_held = 1;
+ lock_is_read_held = true;
if (WARN_ON_ONCE(lock_is_write_held))
lrsp->n_lock_fail++; /* rare, but... */
lrsp->n_lock_acquired++;
cxt.cur_ops->read_delay(&rand);
- lock_is_read_held = 0;
+ lock_is_read_held = false;
cxt.cur_ops->readunlock();
stutter_wait("lock_torture_reader");
@@ -686,7 +680,7 @@ static int lock_torture_reader(void *arg)
static void __torture_print_stats(char *page,
struct lock_stress_stats *statp, bool write)
{
- bool fail = 0;
+ bool fail = false;
int i, n_stress;
long max = 0, min = statp ? statp[0].n_lock_acquired : 0;
long long sum = 0;
@@ -904,7 +898,7 @@ static int __init lock_torture_init(void)
/* Initialize the statistics so that each run gets its own numbers. */
if (nwriters_stress) {
- lock_is_write_held = 0;
+ lock_is_write_held = false;
cxt.lwsa = kmalloc_array(cxt.nrealwriters_stress,
sizeof(*cxt.lwsa),
GFP_KERNEL);
@@ -935,7 +929,7 @@ static int __init lock_torture_init(void)
}
if (nreaders_stress) {
- lock_is_read_held = 0;
+ lock_is_read_held = false;
cxt.lrsa = kmalloc_array(cxt.nrealreaders_stress,
sizeof(*cxt.lrsa),
GFP_KERNEL);
diff --git a/kernel/locking/osq_lock.c b/kernel/locking/osq_lock.c
index 1f7734949ac8..1de006ed3aa8 100644
--- a/kernel/locking/osq_lock.c
+++ b/kernel/locking/osq_lock.c
@@ -154,7 +154,11 @@ bool osq_lock(struct optimistic_spin_queue *lock)
*/
for (;;) {
- if (prev->next == node &&
+ /*
+ * cpu_relax() below implies a compiler barrier which would
+ * prevent this comparison being optimized away.
+ */
+ if (data_race(prev->next) == node &&
cmpxchg(&prev->next, node, NULL) == node)
break;
diff --git a/kernel/locking/qspinlock.c b/kernel/locking/qspinlock.c
index b9515fcc9b29..cbff6ba53d56 100644
--- a/kernel/locking/qspinlock.c
+++ b/kernel/locking/qspinlock.c
@@ -581,4 +581,11 @@ EXPORT_SYMBOL(queued_spin_lock_slowpath);
#include "qspinlock_paravirt.h"
#include "qspinlock.c"
+bool nopvspin __initdata;
+static __init int parse_nopvspin(char *arg)
+{
+ nopvspin = true;
+ return 0;
+}
+early_param("nopvspin", parse_nopvspin);
#endif
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.