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-rw-r--r--kernel/locking/Makefile3
-rw-r--r--kernel/locking/lockdep.c122
-rw-r--r--kernel/locking/lockdep_internals.h6
-rw-r--r--kernel/locking/lockdep_proc.c51
-rw-r--r--kernel/locking/locktorture.c4
-rw-r--r--kernel/locking/mutex.c18
-rw-r--r--kernel/locking/percpu-rwsem.c16
-rw-r--r--kernel/locking/qrwlock.c21
-rw-r--r--kernel/locking/qspinlock.c7
-rw-r--r--kernel/locking/qspinlock_paravirt.h4
-rw-r--r--kernel/locking/rtmutex.c11
-rw-r--r--kernel/locking/rwbase_rt.c7
-rw-r--r--kernel/locking/rwsem.c176
-rw-r--r--kernel/locking/semaphore.c27
-rw-r--r--kernel/locking/spinlock.c66
-rw-r--r--kernel/locking/spinlock_rt.c12
-rw-r--r--kernel/locking/test-ww_mutex.c4
17 files changed, 384 insertions, 171 deletions
diff --git a/kernel/locking/Makefile b/kernel/locking/Makefile
index d51cabf28f38..ea925731fa40 100644
--- a/kernel/locking/Makefile
+++ b/kernel/locking/Makefile
@@ -5,8 +5,9 @@ KCOV_INSTRUMENT := n
obj-y += mutex.o semaphore.o rwsem.o percpu-rwsem.o
-# Avoid recursion lockdep -> KCSAN -> ... -> lockdep.
+# Avoid recursion lockdep -> sanitizer -> ... -> lockdep.
KCSAN_SANITIZE_lockdep.o := n
+KMSAN_SANITIZE_lockdep.o := n
ifdef CONFIG_FUNCTION_TRACER
CFLAGS_REMOVE_lockdep.o = $(CC_FLAGS_FTRACE)
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index 4a882f83aeb9..e3375bc40dad 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -60,23 +60,53 @@
#include "lockdep_internals.h"
-#define CREATE_TRACE_POINTS
#include <trace/events/lock.h>
#ifdef CONFIG_PROVE_LOCKING
-int prove_locking = 1;
+static int prove_locking = 1;
module_param(prove_locking, int, 0644);
#else
#define prove_locking 0
#endif
#ifdef CONFIG_LOCK_STAT
-int lock_stat = 1;
+static int lock_stat = 1;
module_param(lock_stat, int, 0644);
#else
#define lock_stat 0
#endif
+#ifdef CONFIG_SYSCTL
+static struct ctl_table kern_lockdep_table[] = {
+#ifdef CONFIG_PROVE_LOCKING
+ {
+ .procname = "prove_locking",
+ .data = &prove_locking,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+#endif /* CONFIG_PROVE_LOCKING */
+#ifdef CONFIG_LOCK_STAT
+ {
+ .procname = "lock_stat",
+ .data = &lock_stat,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+#endif /* CONFIG_LOCK_STAT */
+ { }
+};
+
+static __init int kernel_lockdep_sysctls_init(void)
+{
+ register_sysctl_init("kernel", kern_lockdep_table);
+ return 0;
+}
+late_initcall(kernel_lockdep_sysctls_init);
+#endif /* CONFIG_SYSCTL */
+
DEFINE_PER_CPU(unsigned int, lockdep_recursion);
EXPORT_PER_CPU_SYMBOL_GPL(lockdep_recursion);
@@ -183,11 +213,9 @@ static DECLARE_BITMAP(list_entries_in_use, MAX_LOCKDEP_ENTRIES);
static struct hlist_head lock_keys_hash[KEYHASH_SIZE];
unsigned long nr_lock_classes;
unsigned long nr_zapped_classes;
-#ifndef CONFIG_DEBUG_LOCKDEP
-static
-#endif
+unsigned long max_lock_class_idx;
struct lock_class lock_classes[MAX_LOCKDEP_KEYS];
-static DECLARE_BITMAP(lock_classes_in_use, MAX_LOCKDEP_KEYS);
+DECLARE_BITMAP(lock_classes_in_use, MAX_LOCKDEP_KEYS);
static inline struct lock_class *hlock_class(struct held_lock *hlock)
{
@@ -338,7 +366,7 @@ static inline void lock_release_holdtime(struct held_lock *hlock)
* elements. These elements are linked together by the lock_entry member in
* struct lock_class.
*/
-LIST_HEAD(all_lock_classes);
+static LIST_HEAD(all_lock_classes);
static LIST_HEAD(free_lock_classes);
/**
@@ -906,8 +934,10 @@ look_up_lock_class(const struct lockdep_map *lock, unsigned int subclass)
* Huh! same key, different name? Did someone trample
* on some memory? We're most confused.
*/
- WARN_ON_ONCE(class->name != lock->name &&
- lock->key != &__lockdep_no_validate__);
+ WARN_ONCE(class->name != lock->name &&
+ lock->key != &__lockdep_no_validate__,
+ "Looking for class \"%s\" with key %ps, but found a different class \"%s\" with the same key\n",
+ lock->name, lock->key, class->name);
return class;
}
}
@@ -1252,6 +1282,7 @@ register_lock_class(struct lockdep_map *lock, unsigned int subclass, int force)
struct lockdep_subclass_key *key;
struct hlist_head *hash_head;
struct lock_class *class;
+ int idx;
DEBUG_LOCKS_WARN_ON(!irqs_disabled());
@@ -1317,6 +1348,9 @@ register_lock_class(struct lockdep_map *lock, unsigned int subclass, int force)
* of classes.
*/
list_move_tail(&class->lock_entry, &all_lock_classes);
+ idx = class - lock_classes;
+ if (idx > max_lock_class_idx)
+ max_lock_class_idx = idx;
if (verbose(class)) {
graph_unlock();
@@ -1378,7 +1412,7 @@ static struct lock_list *alloc_list_entry(void)
*/
static int add_lock_to_list(struct lock_class *this,
struct lock_class *links_to, struct list_head *head,
- unsigned long ip, u16 distance, u8 dep,
+ u16 distance, u8 dep,
const struct lock_trace *trace)
{
struct lock_list *entry;
@@ -3131,19 +3165,15 @@ check_prev_add(struct task_struct *curr, struct held_lock *prev,
* to the previous lock's dependency list:
*/
ret = add_lock_to_list(hlock_class(next), hlock_class(prev),
- &hlock_class(prev)->locks_after,
- next->acquire_ip, distance,
- calc_dep(prev, next),
- *trace);
+ &hlock_class(prev)->locks_after, distance,
+ calc_dep(prev, next), *trace);
if (!ret)
return 0;
ret = add_lock_to_list(hlock_class(prev), hlock_class(next),
- &hlock_class(next)->locks_before,
- next->acquire_ip, distance,
- calc_depb(prev, next),
- *trace);
+ &hlock_class(next)->locks_before, distance,
+ calc_depb(prev, next), *trace);
if (!ret)
return 0;
@@ -3462,7 +3492,7 @@ struct lock_class *lock_chain_get_class(struct lock_chain *chain, int i)
u16 chain_hlock = chain_hlocks[chain->base + i];
unsigned int class_idx = chain_hlock_class_idx(chain_hlock);
- return lock_classes + class_idx - 1;
+ return lock_classes + class_idx;
}
/*
@@ -3530,7 +3560,7 @@ static void print_chain_keys_chain(struct lock_chain *chain)
hlock_id = chain_hlocks[chain->base + i];
chain_key = print_chain_key_iteration(hlock_id, chain_key);
- print_lock_name(lock_classes + chain_hlock_class_idx(hlock_id) - 1);
+ print_lock_name(lock_classes + chain_hlock_class_idx(hlock_id));
printk("\n");
}
}
@@ -4234,14 +4264,13 @@ static void __trace_hardirqs_on_caller(void)
/**
* lockdep_hardirqs_on_prepare - Prepare for enabling interrupts
- * @ip: Caller address
*
* Invoked before a possible transition to RCU idle from exit to user or
* guest mode. This ensures that all RCU operations are done before RCU
* stops watching. After the RCU transition lockdep_hardirqs_on() has to be
* invoked to set the final state.
*/
-void lockdep_hardirqs_on_prepare(unsigned long ip)
+void lockdep_hardirqs_on_prepare(void)
{
if (unlikely(!debug_locks))
return;
@@ -4838,8 +4867,7 @@ EXPORT_SYMBOL_GPL(__lockdep_no_validate__);
static void
print_lock_nested_lock_not_held(struct task_struct *curr,
- struct held_lock *hlock,
- unsigned long ip)
+ struct held_lock *hlock)
{
if (!debug_locks_off())
return;
@@ -5015,7 +5043,7 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
chain_key = iterate_chain_key(chain_key, hlock_id(hlock));
if (nest_lock && !__lock_is_held(nest_lock, -1)) {
- print_lock_nested_lock_not_held(curr, hlock, ip);
+ print_lock_nested_lock_not_held(curr, hlock);
return 0;
}
@@ -5212,9 +5240,10 @@ __lock_set_class(struct lockdep_map *lock, const char *name,
return 0;
}
- lockdep_init_map_waits(lock, name, key, 0,
- lock->wait_type_inner,
- lock->wait_type_outer);
+ lockdep_init_map_type(lock, name, key, 0,
+ lock->wait_type_inner,
+ lock->wait_type_outer,
+ lock->lock_type);
class = register_lock_class(lock, subclass, 0);
hlock->class_idx = class - lock_classes;
@@ -5406,7 +5435,7 @@ static struct pin_cookie __lock_pin_lock(struct lockdep_map *lock)
* be guessable and still allows some pin nesting in
* our u32 pin_count.
*/
- cookie.val = 1 + (prandom_u32() >> 16);
+ cookie.val = 1 + (sched_clock() & 0xffff);
hlock->pin_count += cookie.val;
return cookie;
}
@@ -6000,6 +6029,8 @@ static void zap_class(struct pending_free *pf, struct lock_class *class)
WRITE_ONCE(class->name, NULL);
nr_lock_classes--;
__clear_bit(class - lock_classes, lock_classes_in_use);
+ if (class - lock_classes == max_lock_class_idx)
+ max_lock_class_idx--;
} else {
WARN_ONCE(true, "%s() failed for class %s\n", __func__,
class->name);
@@ -6011,13 +6042,10 @@ static void zap_class(struct pending_free *pf, struct lock_class *class)
static void reinit_class(struct lock_class *class)
{
- void *const p = class;
- const unsigned int offset = offsetof(struct lock_class, key);
-
WARN_ON_ONCE(!class->lock_entry.next);
WARN_ON_ONCE(!list_empty(&class->locks_after));
WARN_ON_ONCE(!list_empty(&class->locks_before));
- memset(p + offset, 0, sizeof(*class) - offset);
+ memset_startat(class, 0, key);
WARN_ON_ONCE(!class->lock_entry.next);
WARN_ON_ONCE(!list_empty(&class->locks_after));
WARN_ON_ONCE(!list_empty(&class->locks_before));
@@ -6290,7 +6318,13 @@ void lockdep_reset_lock(struct lockdep_map *lock)
lockdep_reset_lock_reg(lock);
}
-/* Unregister a dynamically allocated key. */
+/*
+ * Unregister a dynamically allocated key.
+ *
+ * Unlike lockdep_register_key(), a search is always done to find a matching
+ * key irrespective of debug_locks to avoid potential invalid access to freed
+ * memory in lock_class entry.
+ */
void lockdep_unregister_key(struct lock_class_key *key)
{
struct hlist_head *hash_head = keyhashentry(key);
@@ -6305,10 +6339,8 @@ void lockdep_unregister_key(struct lock_class_key *key)
return;
raw_local_irq_save(flags);
- if (!graph_lock())
- goto out_irq;
+ lockdep_lock();
- pf = get_pending_free();
hlist_for_each_entry_rcu(k, hash_head, hash_entry) {
if (k == key) {
hlist_del_rcu(&k->hash_entry);
@@ -6316,11 +6348,13 @@ void lockdep_unregister_key(struct lock_class_key *key)
break;
}
}
- WARN_ON_ONCE(!found);
- __lockdep_free_key_range(pf, key, 1);
- call_rcu_zapped(pf);
- graph_unlock();
-out_irq:
+ WARN_ON_ONCE(!found && debug_locks);
+ if (found) {
+ pf = get_pending_free();
+ __lockdep_free_key_range(pf, key, 1);
+ call_rcu_zapped(pf);
+ }
+ lockdep_unlock();
raw_local_irq_restore(flags);
/* Wait until is_dynamic_key() has finished accessing k->hash_entry. */
@@ -6539,7 +6573,7 @@ void lockdep_rcu_suspicious(const char *file, const int line, const char *s)
/*
* If a CPU is in the RCU-free window in idle (ie: in the section
- * between rcu_idle_enter() and rcu_idle_exit(), then RCU
+ * between ct_idle_enter() and ct_idle_exit(), then RCU
* considers that CPU to be in an "extended quiescent state",
* which means that RCU will be completely ignoring that CPU.
* Therefore, rcu_read_lock() and friends have absolutely no
diff --git a/kernel/locking/lockdep_internals.h b/kernel/locking/lockdep_internals.h
index ecb8662e7a4e..bbe9000260d0 100644
--- a/kernel/locking/lockdep_internals.h
+++ b/kernel/locking/lockdep_internals.h
@@ -121,7 +121,6 @@ static const unsigned long LOCKF_USED_IN_IRQ_READ =
#define MAX_LOCKDEP_CHAIN_HLOCKS (MAX_LOCKDEP_CHAINS*5)
-extern struct list_head all_lock_classes;
extern struct lock_chain lock_chains[];
#define LOCK_USAGE_CHARS (2*XXX_LOCK_USAGE_STATES + 1)
@@ -151,6 +150,10 @@ extern unsigned int nr_large_chain_blocks;
extern unsigned int max_lockdep_depth;
extern unsigned int max_bfs_queue_depth;
+extern unsigned long max_lock_class_idx;
+
+extern struct lock_class lock_classes[MAX_LOCKDEP_KEYS];
+extern unsigned long lock_classes_in_use[];
#ifdef CONFIG_PROVE_LOCKING
extern unsigned long lockdep_count_forward_deps(struct lock_class *);
@@ -205,7 +208,6 @@ struct lockdep_stats {
};
DECLARE_PER_CPU(struct lockdep_stats, lockdep_stats);
-extern struct lock_class lock_classes[MAX_LOCKDEP_KEYS];
#define __debug_atomic_inc(ptr) \
this_cpu_inc(lockdep_stats.ptr);
diff --git a/kernel/locking/lockdep_proc.c b/kernel/locking/lockdep_proc.c
index b8d9a050c337..15fdc7fa5c68 100644
--- a/kernel/locking/lockdep_proc.c
+++ b/kernel/locking/lockdep_proc.c
@@ -24,14 +24,33 @@
#include "lockdep_internals.h"
+/*
+ * Since iteration of lock_classes is done without holding the lockdep lock,
+ * it is not safe to iterate all_lock_classes list directly as the iteration
+ * may branch off to free_lock_classes or the zapped list. Iteration is done
+ * directly on the lock_classes array by checking the lock_classes_in_use
+ * bitmap and max_lock_class_idx.
+ */
+#define iterate_lock_classes(idx, class) \
+ for (idx = 0, class = lock_classes; idx <= max_lock_class_idx; \
+ idx++, class++)
+
static void *l_next(struct seq_file *m, void *v, loff_t *pos)
{
- return seq_list_next(v, &all_lock_classes, pos);
+ struct lock_class *class = v;
+
+ ++class;
+ *pos = class - lock_classes;
+ return (*pos > max_lock_class_idx) ? NULL : class;
}
static void *l_start(struct seq_file *m, loff_t *pos)
{
- return seq_list_start_head(&all_lock_classes, *pos);
+ unsigned long idx = *pos;
+
+ if (idx > max_lock_class_idx)
+ return NULL;
+ return lock_classes + idx;
}
static void l_stop(struct seq_file *m, void *v)
@@ -57,14 +76,16 @@ static void print_name(struct seq_file *m, struct lock_class *class)
static int l_show(struct seq_file *m, void *v)
{
- struct lock_class *class = list_entry(v, struct lock_class, lock_entry);
+ struct lock_class *class = v;
struct lock_list *entry;
char usage[LOCK_USAGE_CHARS];
+ int idx = class - lock_classes;
- if (v == &all_lock_classes) {
+ if (v == lock_classes)
seq_printf(m, "all lock classes:\n");
+
+ if (!test_bit(idx, lock_classes_in_use))
return 0;
- }
seq_printf(m, "%p", class->key);
#ifdef CONFIG_DEBUG_LOCKDEP
@@ -220,8 +241,11 @@ static int lockdep_stats_show(struct seq_file *m, void *v)
#ifdef CONFIG_PROVE_LOCKING
struct lock_class *class;
+ unsigned long idx;
- list_for_each_entry(class, &all_lock_classes, lock_entry) {
+ iterate_lock_classes(idx, class) {
+ if (!test_bit(idx, lock_classes_in_use))
+ continue;
if (class->usage_mask == 0)
nr_unused++;
@@ -254,6 +278,7 @@ static int lockdep_stats_show(struct seq_file *m, void *v)
sum_forward_deps += lockdep_count_forward_deps(class);
}
+
#ifdef CONFIG_DEBUG_LOCKDEP
DEBUG_LOCKS_WARN_ON(debug_atomic_read(nr_unused_locks) != nr_unused);
#endif
@@ -345,6 +370,8 @@ static int lockdep_stats_show(struct seq_file *m, void *v)
seq_printf(m, " max bfs queue depth: %11u\n",
max_bfs_queue_depth);
#endif
+ seq_printf(m, " max lock class index: %11lu\n",
+ max_lock_class_idx);
lockdep_stats_debug_show(m);
seq_printf(m, " debug_locks: %11u\n",
debug_locks);
@@ -622,12 +649,16 @@ static int lock_stat_open(struct inode *inode, struct file *file)
if (!res) {
struct lock_stat_data *iter = data->stats;
struct seq_file *m = file->private_data;
+ unsigned long idx;
- list_for_each_entry(class, &all_lock_classes, lock_entry) {
+ iterate_lock_classes(idx, class) {
+ if (!test_bit(idx, lock_classes_in_use))
+ continue;
iter->class = class;
iter->stats = lock_stats(class);
iter++;
}
+
data->iter_end = iter;
sort(data->stats, data->iter_end - data->stats,
@@ -645,6 +676,7 @@ static ssize_t lock_stat_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct lock_class *class;
+ unsigned long idx;
char c;
if (count) {
@@ -654,8 +686,11 @@ static ssize_t lock_stat_write(struct file *file, const char __user *buf,
if (c != '0')
return count;
- list_for_each_entry(class, &all_lock_classes, lock_entry)
+ iterate_lock_classes(idx, class) {
+ if (!test_bit(idx, lock_classes_in_use))
+ continue;
clear_lock_stats(class);
+ }
}
return count;
}
diff --git a/kernel/locking/locktorture.c b/kernel/locking/locktorture.c
index 397ac13d2ef7..9c2fb613a55d 100644
--- a/kernel/locking/locktorture.c
+++ b/kernel/locking/locktorture.c
@@ -1047,7 +1047,7 @@ static int __init lock_torture_init(void)
sizeof(writer_tasks[0]),
GFP_KERNEL);
if (writer_tasks == NULL) {
- VERBOSE_TOROUT_ERRSTRING("writer_tasks: Out of memory");
+ TOROUT_ERRSTRING("writer_tasks: Out of memory");
firsterr = -ENOMEM;
goto unwind;
}
@@ -1058,7 +1058,7 @@ static int __init lock_torture_init(void)
sizeof(reader_tasks[0]),
GFP_KERNEL);
if (reader_tasks == NULL) {
- VERBOSE_TOROUT_ERRSTRING("reader_tasks: Out of memory");
+ TOROUT_ERRSTRING("reader_tasks: Out of memory");
kfree(writer_tasks);
writer_tasks = NULL;
firsterr = -ENOMEM;
diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c
index 5e3585950ec8..d973fe6041bf 100644
--- a/kernel/locking/mutex.c
+++ b/kernel/locking/mutex.c
@@ -30,6 +30,9 @@
#include <linux/debug_locks.h>
#include <linux/osq_lock.h>
+#define CREATE_TRACE_POINTS
+#include <trace/events/lock.h>
+
#ifndef CONFIG_PREEMPT_RT
#include "mutex.h"
@@ -599,12 +602,14 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas
preempt_disable();
mutex_acquire_nest(&lock->dep_map, subclass, 0, nest_lock, ip);
+ trace_contention_begin(lock, LCB_F_MUTEX | LCB_F_SPIN);
if (__mutex_trylock(lock) ||
mutex_optimistic_spin(lock, ww_ctx, NULL)) {
/* got the lock, yay! */
lock_acquired(&lock->dep_map, ip);
if (ww_ctx)
ww_mutex_set_context_fastpath(ww, ww_ctx);
+ trace_contention_end(lock, 0);
preempt_enable();
return 0;
}
@@ -641,6 +646,7 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas
}
set_current_state(state);
+ trace_contention_begin(lock, LCB_F_MUTEX);
for (;;) {
bool first;
@@ -680,10 +686,16 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas
* state back to RUNNING and fall through the next schedule(),
* or we must see its unlock and acquire.
*/
- if (__mutex_trylock_or_handoff(lock, first) ||
- (first && mutex_optimistic_spin(lock, ww_ctx, &waiter)))
+ if (__mutex_trylock_or_handoff(lock, first))
break;
+ if (first) {
+ trace_contention_begin(lock, LCB_F_MUTEX | LCB_F_SPIN);
+ if (mutex_optimistic_spin(lock, ww_ctx, &waiter))
+ break;
+ trace_contention_begin(lock, LCB_F_MUTEX);
+ }
+
raw_spin_lock(&lock->wait_lock);
}
raw_spin_lock(&lock->wait_lock);
@@ -707,6 +719,7 @@ acquired:
skip_wait:
/* got the lock - cleanup and rejoice! */
lock_acquired(&lock->dep_map, ip);
+ trace_contention_end(lock, 0);
if (ww_ctx)
ww_mutex_lock_acquired(ww, ww_ctx);
@@ -719,6 +732,7 @@ err:
__set_current_state(TASK_RUNNING);
__mutex_remove_waiter(lock, &waiter);
err_early_kill:
+ trace_contention_end(lock, ret);
raw_spin_unlock(&lock->wait_lock);
debug_mutex_free_waiter(&waiter);
mutex_release(&lock->dep_map, ip);
diff --git a/kernel/locking/percpu-rwsem.c b/kernel/locking/percpu-rwsem.c
index 70a32a576f3f..185bd1c906b0 100644
--- a/kernel/locking/percpu-rwsem.c
+++ b/kernel/locking/percpu-rwsem.c
@@ -7,7 +7,9 @@
#include <linux/rcupdate.h>
#include <linux/sched.h>
#include <linux/sched/task.h>
+#include <linux/sched/debug.h>
#include <linux/errno.h>
+#include <trace/events/lock.h>
int __percpu_init_rwsem(struct percpu_rw_semaphore *sem,
const char *name, struct lock_class_key *key)
@@ -162,7 +164,7 @@ static void percpu_rwsem_wait(struct percpu_rw_semaphore *sem, bool reader)
__set_current_state(TASK_RUNNING);
}
-bool __percpu_down_read(struct percpu_rw_semaphore *sem, bool try)
+bool __sched __percpu_down_read(struct percpu_rw_semaphore *sem, bool try)
{
if (__percpu_down_read_trylock(sem))
return true;
@@ -170,9 +172,11 @@ bool __percpu_down_read(struct percpu_rw_semaphore *sem, bool try)
if (try)
return false;
+ trace_contention_begin(sem, LCB_F_PERCPU | LCB_F_READ);
preempt_enable();
percpu_rwsem_wait(sem, /* .reader = */ true);
preempt_disable();
+ trace_contention_end(sem, 0);
return true;
}
@@ -188,6 +192,12 @@ EXPORT_SYMBOL_GPL(__percpu_down_read);
__sum; \
})
+bool percpu_is_read_locked(struct percpu_rw_semaphore *sem)
+{
+ return per_cpu_sum(*sem->read_count) != 0 && !atomic_read(&sem->block);
+}
+EXPORT_SYMBOL_GPL(percpu_is_read_locked);
+
/*
* Return true if the modular sum of the sem->read_count per-CPU variable is
* zero. If this sum is zero, then it is stable due to the fact that if any
@@ -211,10 +221,11 @@ static bool readers_active_check(struct percpu_rw_semaphore *sem)
return true;
}
-void percpu_down_write(struct percpu_rw_semaphore *sem)
+void __sched percpu_down_write(struct percpu_rw_semaphore *sem)
{
might_sleep();
rwsem_acquire(&sem->dep_map, 0, 0, _RET_IP_);
+ trace_contention_begin(sem, LCB_F_PERCPU | LCB_F_WRITE);
/* Notify readers to take the slow path. */
rcu_sync_enter(&sem->rss);
@@ -236,6 +247,7 @@ void percpu_down_write(struct percpu_rw_semaphore *sem)
/* Wait for all active readers to complete. */
rcuwait_wait_event(&sem->writer, readers_active_check(sem), TASK_UNINTERRUPTIBLE);
+ trace_contention_end(sem, 0);
}
EXPORT_SYMBOL_GPL(percpu_down_write);
diff --git a/kernel/locking/qrwlock.c b/kernel/locking/qrwlock.c
index ec36b73f4733..d2ef312a8611 100644
--- a/kernel/locking/qrwlock.c
+++ b/kernel/locking/qrwlock.c
@@ -12,12 +12,13 @@
#include <linux/percpu.h>
#include <linux/hardirq.h>
#include <linux/spinlock.h>
+#include <trace/events/lock.h>
/**
- * queued_read_lock_slowpath - acquire read lock of a queue rwlock
- * @lock: Pointer to queue rwlock structure
+ * queued_read_lock_slowpath - acquire read lock of a queued rwlock
+ * @lock: Pointer to queued rwlock structure
*/
-void queued_read_lock_slowpath(struct qrwlock *lock)
+void __lockfunc queued_read_lock_slowpath(struct qrwlock *lock)
{
/*
* Readers come here when they cannot get the lock without waiting
@@ -34,6 +35,8 @@ void queued_read_lock_slowpath(struct qrwlock *lock)
}
atomic_sub(_QR_BIAS, &lock->cnts);
+ trace_contention_begin(lock, LCB_F_SPIN | LCB_F_READ);
+
/*
* Put the reader into the wait queue
*/
@@ -51,17 +54,21 @@ void queued_read_lock_slowpath(struct qrwlock *lock)
* Signal the next one in queue to become queue head
*/
arch_spin_unlock(&lock->wait_lock);
+
+ trace_contention_end(lock, 0);
}
EXPORT_SYMBOL(queued_read_lock_slowpath);
/**
- * queued_write_lock_slowpath - acquire write lock of a queue rwlock
- * @lock : Pointer to queue rwlock structure
+ * queued_write_lock_slowpath - acquire write lock of a queued rwlock
+ * @lock : Pointer to queued rwlock structure
*/
-void queued_write_lock_slowpath(struct qrwlock *lock)
+void __lockfunc queued_write_lock_slowpath(struct qrwlock *lock)
{
int cnts;
+ trace_contention_begin(lock, LCB_F_SPIN | LCB_F_WRITE);
+
/* Put the writer into the wait queue */
arch_spin_lock(&lock->wait_lock);
@@ -79,5 +86,7 @@ void queued_write_lock_slowpath(struct qrwlock *lock)
} while (!atomic_try_cmpxchg_acquire(&lock->cnts, &cnts, _QW_LOCKED));
unlock:
arch_spin_unlock(&lock->wait_lock);
+
+ trace_contention_end(lock, 0);
}
EXPORT_SYMBOL(queued_write_lock_slowpath);
diff --git a/kernel/locking/qspinlock.c b/kernel/locking/qspinlock.c
index cbff6ba53d56..2b23378775fe 100644
--- a/kernel/locking/qspinlock.c
+++ b/kernel/locking/qspinlock.c
@@ -22,6 +22,7 @@
#include <linux/prefetch.h>
#include <asm/byteorder.h>
#include <asm/qspinlock.h>
+#include <trace/events/lock.h>
/*
* Include queued spinlock statistics code
@@ -312,7 +313,7 @@ static __always_inline u32 __pv_wait_head_or_lock(struct qspinlock *lock,
* contended : (*,x,y) +--> (*,0,0) ---> (*,0,1) -' :
* queue : ^--' :
*/
-void queued_spin_lock_slowpath(struct qspinlock *lock, u32 val)
+void __lockfunc queued_spin_lock_slowpath(struct qspinlock *lock, u32 val)
{
struct mcs_spinlock *prev, *next, *node;
u32 old, tail;
@@ -401,6 +402,8 @@ pv_queue:
idx = node->count++;
tail = encode_tail(smp_processor_id(), idx);
+ trace_contention_begin(lock, LCB_F_SPIN);
+
/*
* 4 nodes are allocated based on the assumption that there will
* not be nested NMIs taking spinlocks. That may not be true in
@@ -554,6 +557,8 @@ locked:
pv_kick_node(lock, next);
release:
+ trace_contention_end(lock, 0);
+
/*
* release the node
*/
diff --git a/kernel/locking/qspinlock_paravirt.h b/kernel/locking/qspinlock_paravirt.h
index e84d21aa0722..6afc249ce697 100644
--- a/kernel/locking/qspinlock_paravirt.h
+++ b/kernel/locking/qspinlock_paravirt.h
@@ -489,7 +489,7 @@ gotlock:
* PV versions of the unlock fastpath and slowpath functions to be used
* instead of queued_spin_unlock().
*/
-__visible void
+__visible __lockfunc void
__pv_queued_spin_unlock_slowpath(struct qspinlock *lock, u8 locked)
{
struct pv_node *node;
@@ -544,7 +544,7 @@ __pv_queued_spin_unlock_slowpath(struct qspinlock *lock, u8 locked)
#include <asm/qspinlock_paravirt.h>
#ifndef __pv_queued_spin_unlock
-__visible void __pv_queued_spin_unlock(struct qspinlock *lock)
+__visible __lockfunc void __pv_queued_spin_unlock(struct qspinlock *lock)
{
u8 locked;
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index 8555c4efe97c..7779ee8abc2a 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -24,6 +24,8 @@
#include <linux/sched/wake_q.h>
#include <linux/ww_mutex.h>
+#include <trace/events/lock.h>
+
#include "rtmutex_common.h"
#ifndef WW_RT
@@ -1579,6 +1581,8 @@ static int __sched __rt_mutex_slowlock(struct rt_mutex_base *lock,
set_current_state(state);
+ trace_contention_begin(lock, LCB_F_RT);
+
ret = task_blocks_on_rt_mutex(lock, waiter, current, ww_ctx, chwalk);
if (likely(!ret))
ret = rt_mutex_slowlock_block(lock, ww_ctx, state, NULL, waiter);
@@ -1601,6 +1605,9 @@ static int __sched __rt_mutex_slowlock(struct rt_mutex_base *lock,
* unconditionally. We might have to fix that up.
*/
fixup_rt_mutex_waiters(lock);
+
+ trace_contention_end(lock, ret);
+
return ret;
}
@@ -1683,6 +1690,8 @@ static void __sched rtlock_slowlock_locked(struct rt_mutex_base *lock)
/* Save current state and set state to TASK_RTLOCK_WAIT */
current_save_and_set_rtlock_wait_state();
+ trace_contention_begin(lock, LCB_F_RT);
+
task_blocks_on_rt_mutex(lock, &waiter, current, NULL, RT_MUTEX_MIN_CHAINWALK);
for (;;) {
@@ -1712,6 +1721,8 @@ static void __sched rtlock_slowlock_locked(struct rt_mutex_base *lock)
*/
fixup_rt_mutex_waiters(lock);
debug_rt_mutex_free_waiter(&waiter);
+
+ trace_contention_end(lock, 0);
}
static __always_inline void __sched rtlock_slowlock(struct rt_mutex_base *lock)
diff --git a/kernel/locking/rwbase_rt.c b/kernel/locking/rwbase_rt.c
index 6fd3162e4098..c201aadb9301 100644
--- a/kernel/locking/rwbase_rt.c
+++ b/kernel/locking/rwbase_rt.c
@@ -112,6 +112,8 @@ static int __sched __rwbase_read_lock(struct rwbase_rt *rwb,
* Reader2 to call up_read(), which might be unbound.
*/
+ trace_contention_begin(rwb, LCB_F_RT | LCB_F_READ);
+
/*
* For rwlocks this returns 0 unconditionally, so the below
* !ret conditionals are optimized out.
@@ -130,6 +132,8 @@ static int __sched __rwbase_read_lock(struct rwbase_rt *rwb,
raw_spin_unlock_irq(&rtm->wait_lock);
if (!ret)
rwbase_rtmutex_unlock(rtm);
+
+ trace_contention_end(rwb, ret);
return ret;
}
@@ -247,11 +251,13 @@ static int __sched rwbase_write_lock(struct rwbase_rt *rwb,
goto out_unlock;
rwbase_set_and_save_current_state(state);
+ trace_contention_begin(rwb, LCB_F_RT | LCB_F_WRITE);
for (;;) {
/* Optimized out for rwlocks */
if (rwbase_signal_pending_state(state, current)) {
rwbase_restore_current_state();
__rwbase_write_unlock(rwb, 0, flags);
+ trace_contention_end(rwb, -EINTR);
return -EINTR;
}
@@ -265,6 +271,7 @@ static int __sched rwbase_write_lock(struct rwbase_rt *rwb,
set_current_state(state);
}
rwbase_restore_current_state();
+ trace_contention_end(rwb, 0);
out_unlock:
raw_spin_unlock_irqrestore(&rtm->wait_lock, flags);
diff --git a/kernel/locking/rwsem.c b/kernel/locking/rwsem.c
index 69aba4abe104..44873594de03 100644
--- a/kernel/locking/rwsem.c
+++ b/kernel/locking/rwsem.c
@@ -27,6 +27,7 @@
#include <linux/export.h>
#include <linux/rwsem.h>
#include <linux/atomic.h>
+#include <trace/events/lock.h>
#ifndef CONFIG_PREEMPT_RT
#include "lock_events.h"
@@ -132,14 +133,19 @@
* the owner value concurrently without lock. Read from owner, however,
* may not need READ_ONCE() as long as the pointer value is only used
* for comparison and isn't being dereferenced.
+ *
+ * Both rwsem_{set,clear}_owner() functions should be in the same
+ * preempt disable section as the atomic op that changes sem->count.
*/
static inline void rwsem_set_owner(struct rw_semaphore *sem)
{
+ lockdep_assert_preemption_disabled();
atomic_long_set(&sem->owner, (long)current);
}
static inline void rwsem_clear_owner(struct rw_semaphore *sem)
{
+ lockdep_assert_preemption_disabled();
atomic_long_set(&sem->owner, 0);
}
@@ -250,13 +256,16 @@ static inline bool rwsem_read_trylock(struct rw_semaphore *sem, long *cntp)
static inline bool rwsem_write_trylock(struct rw_semaphore *sem)
{
long tmp = RWSEM_UNLOCKED_VALUE;
+ bool ret = false;
+ preempt_disable();
if (atomic_long_try_cmpxchg_acquire(&sem->count, &tmp, RWSEM_WRITER_LOCKED)) {
rwsem_set_owner(sem);
- return true;
+ ret = true;
}
- return false;
+ preempt_enable();
+ return ret;
}
/*
@@ -334,8 +343,6 @@ struct rwsem_waiter {
struct task_struct *task;
enum rwsem_waiter_type type;
unsigned long timeout;
-
- /* Writer only, not initialized in reader */
bool handoff_set;
};
#define rwsem_first_waiter(sem) \
@@ -375,16 +382,19 @@ rwsem_add_waiter(struct rw_semaphore *sem, struct rwsem_waiter *waiter)
*
* Both rwsem_mark_wake() and rwsem_try_write_lock() contain a full 'copy' of
* this function. Modify with care.
+ *
+ * Return: true if wait_list isn't empty and false otherwise
*/
-static inline void
+static inline bool
rwsem_del_waiter(struct rw_semaphore *sem, struct rwsem_waiter *waiter)
{
lockdep_assert_held(&sem->wait_lock);
list_del(&waiter->list);
if (likely(!list_empty(&sem->wait_list)))
- return;
+ return true;
atomic_long_andnot(RWSEM_FLAG_HANDOFF | RWSEM_FLAG_WAITERS, &sem->count);
+ return false;
}
/*
@@ -455,10 +465,12 @@ static void rwsem_mark_wake(struct rw_semaphore *sem,
* to give up the lock), request a HANDOFF to
* force the issue.
*/
- if (!(oldcount & RWSEM_FLAG_HANDOFF) &&
- time_after(jiffies, waiter->timeout)) {
- adjustment -= RWSEM_FLAG_HANDOFF;
- lockevent_inc(rwsem_rlock_handoff);
+ if (time_after(jiffies, waiter->timeout)) {
+ if (!(oldcount & RWSEM_FLAG_HANDOFF)) {
+ adjustment -= RWSEM_FLAG_HANDOFF;
+ lockevent_inc(rwsem_rlock_handoff);
+ }
+ waiter->handoff_set = true;
}
atomic_long_add(-adjustment, &sem->count);
@@ -559,6 +571,33 @@ static void rwsem_mark_wake(struct rw_semaphore *sem,
}
/*
+ * Remove a waiter and try to wake up other waiters in the wait queue
+ * This function is called from the out_nolock path of both the reader and
+ * writer slowpaths with wait_lock held. It releases the wait_lock and
+ * optionally wake up waiters before it returns.
+ */
+static inline void
+rwsem_del_wake_waiter(struct rw_semaphore *sem, struct rwsem_waiter *waiter,
+ struct wake_q_head *wake_q)
+ __releases(&sem->wait_lock)
+{
+ bool first = rwsem_first_waiter(sem) == waiter;
+
+ wake_q_init(wake_q);
+
+ /*
+ * If the wait_list isn't empty and the waiter to be deleted is
+ * the first waiter, we wake up the remaining waiters as they may
+ * be eligible to acquire or spin on the lock.
+ */
+ if (rwsem_del_waiter(sem, waiter) && first)
+ rwsem_mark_wake(sem, RWSEM_WAKE_ANY, wake_q);
+ raw_spin_unlock_irq(&sem->wait_lock);
+ if (!wake_q_empty(wake_q))
+ wake_up_q(wake_q);
+}
+
+/*
* This function must be called with the sem->wait_lock held to prevent
* race conditions between checking the rwsem wait list and setting the
* sem->count accordingly.
@@ -568,7 +607,7 @@ static void rwsem_mark_wake(struct rw_semaphore *sem,
static inline bool rwsem_try_write_lock(struct rw_semaphore *sem,
struct rwsem_waiter *waiter)
{
- bool first = rwsem_first_waiter(sem) == waiter;
+ struct rwsem_waiter *first = rwsem_first_waiter(sem);
long count, new;
lockdep_assert_held(&sem->wait_lock);
@@ -578,11 +617,20 @@ static inline bool rwsem_try_write_lock(struct rw_semaphore *sem,
bool has_handoff = !!(count & RWSEM_FLAG_HANDOFF);
if (has_handoff) {
- if (!first)
+ /*
+ * Honor handoff bit and yield only when the first
+ * waiter is the one that set it. Otherwisee, we
+ * still try to acquire the rwsem.
+ */
+ if (first->handoff_set && (waiter != first))
return false;
- /* First waiter inherits a previously set handoff bit */
- waiter->handoff_set = true;
+ /*
+ * First waiter can inherit a previously set handoff
+ * bit and spin on rwsem if lock acquisition fails.
+ */
+ if (waiter == first)
+ waiter->handoff_set = true;
}
new = count;
@@ -901,7 +949,7 @@ done:
*/
static inline void clear_nonspinnable(struct rw_semaphore *sem)
{
- if (rwsem_test_oflags(sem, RWSEM_NONSPINNABLE))
+ if (unlikely(rwsem_test_oflags(sem, RWSEM_NONSPINNABLE)))
atomic_long_andnot(RWSEM_NONSPINNABLE, &sem->owner);
}
@@ -926,6 +974,31 @@ rwsem_spin_on_owner(struct rw_semaphore *sem)
#endif
/*
+ * Prepare to wake up waiter(s) in the wait queue by putting them into the
+ * given wake_q if the rwsem lock owner isn't a writer. If rwsem is likely
+ * reader-owned, wake up read lock waiters in queue front or wake up any
+ * front waiter otherwise.
+
+ * This is being called from both reader and writer slow paths.
+ */
+static inline void rwsem_cond_wake_waiter(struct rw_semaphore *sem, long count,
+ struct wake_q_head *wake_q)
+{
+ enum rwsem_wake_type wake_type;
+
+ if (count & RWSEM_WRITER_MASK)
+ return;
+
+ if (count & RWSEM_READER_MASK) {
+ wake_type = RWSEM_WAKE_READERS;
+ } else {
+ wake_type = RWSEM_WAKE_ANY;
+ clear_nonspinnable(sem);
+ }
+ rwsem_mark_wake(sem, wake_type, wake_q);
+}
+
+/*
* Wait for the read lock to be granted
*/
static struct rw_semaphore __sched *
@@ -935,7 +1008,6 @@ rwsem_down_read_slowpath(struct rw_semaphore *sem, long count, unsigned int stat
long rcnt = (count >> RWSEM_READER_SHIFT);
struct rwsem_waiter waiter;
DEFINE_WAKE_Q(wake_q);
- bool wake = false;
/*
* To prevent a constant stream of readers from starving a sleeping
@@ -972,17 +1044,17 @@ queue:
waiter.task = current;
waiter.type = RWSEM_WAITING_FOR_READ;
waiter.timeout = jiffies + RWSEM_WAIT_TIMEOUT;
+ waiter.handoff_set = false;
raw_spin_lock_irq(&sem->wait_lock);
if (list_empty(&sem->wait_list)) {
/*
* In case the wait queue is empty and the lock isn't owned
- * by a writer or has the handoff bit set, this reader can
- * exit the slowpath and return immediately as its
- * RWSEM_READER_BIAS has already been set in the count.
+ * by a writer, this reader can exit the slowpath and return
+ * immediately as its RWSEM_READER_BIAS has already been set
+ * in the count.
*/
- if (!(atomic_long_read(&sem->count) &
- (RWSEM_WRITER_MASK | RWSEM_FLAG_HANDOFF))) {
+ if (!(atomic_long_read(&sem->count) & RWSEM_WRITER_MASK)) {
/* Provide lock ACQUIRE */
smp_acquire__after_ctrl_dep();
raw_spin_unlock_irq(&sem->wait_lock);
@@ -997,22 +1069,13 @@ queue:
/* we're now waiting on the lock, but no longer actively locking */
count = atomic_long_add_return(adjustment, &sem->count);
- /*
- * If there are no active locks, wake the front queued process(es).
- *
- * If there are no writers and we are first in the queue,
- * wake our own waiter to join the existing active readers !
- */
- if (!(count & RWSEM_LOCK_MASK)) {
- clear_nonspinnable(sem);
- wake = true;
- }
- if (wake || (!(count & RWSEM_WRITER_MASK) &&
- (adjustment & RWSEM_FLAG_WAITERS)))
- rwsem_mark_wake(sem, RWSEM_WAKE_ANY, &wake_q);
-
+ rwsem_cond_wake_waiter(sem, count, &wake_q);
raw_spin_unlock_irq(&sem->wait_lock);
- wake_up_q(&wake_q);
+
+ if (!wake_q_empty(&wake_q))
+ wake_up_q(&wake_q);
+
+ trace_contention_begin(sem, LCB_F_READ);
/* wait to be given the lock */
for (;;) {
@@ -1035,23 +1098,23 @@ queue:
__set_current_state(TASK_RUNNING);
lockevent_inc(rwsem_rlock);
+ trace_contention_end(sem, 0);
return sem;
out_nolock:
- rwsem_del_waiter(sem, &waiter);
- raw_spin_unlock_irq(&sem->wait_lock);
+ rwsem_del_wake_waiter(sem, &waiter, &wake_q);
__set_current_state(TASK_RUNNING);
lockevent_inc(rwsem_rlock_fail);
+ trace_contention_end(sem, -EINTR);
return ERR_PTR(-EINTR);
}
/*
* Wait until we successfully acquire the write lock
*/
-static struct rw_semaphore *
+static struct rw_semaphore __sched *
rwsem_down_write_slowpath(struct rw_semaphore *sem, int state)
{
- long count;
struct rwsem_waiter waiter;
DEFINE_WAKE_Q(wake_q);
@@ -1075,23 +1138,8 @@ rwsem_down_write_slowpath(struct rw_semaphore *sem, int state)
/* we're now waiting on the lock */
if (rwsem_first_waiter(sem) != &waiter) {
- count = atomic_long_read(&sem->count);
-
- /*
- * If there were already threads queued before us and:
- * 1) there are no active locks, wake the front
- * queued process(es) as the handoff bit might be set.
- * 2) there are no active writers and some readers, the lock
- * must be read owned; so we try to wake any read lock
- * waiters that were queued ahead of us.
- */
- if (count & RWSEM_WRITER_MASK)
- goto wait;
-
- rwsem_mark_wake(sem, (count & RWSEM_READER_MASK)
- ? RWSEM_WAKE_READERS
- : RWSEM_WAKE_ANY, &wake_q);
-
+ rwsem_cond_wake_waiter(sem, atomic_long_read(&sem->count),
+ &wake_q);
if (!wake_q_empty(&wake_q)) {
/*
* We want to minimize wait_lock hold time especially
@@ -1099,16 +1147,16 @@ rwsem_down_write_slowpath(struct rw_semaphore *sem, int state)
*/
raw_spin_unlock_irq(&sem->wait_lock);
wake_up_q(&wake_q);
- wake_q_init(&wake_q); /* Used again, reinit */
raw_spin_lock_irq(&sem->wait_lock);
}
} else {
atomic_long_or(RWSEM_FLAG_WAITERS, &sem->count);
}
-wait:
/* wait until we successfully acquire the lock */
set_current_state(state);
+ trace_contention_begin(sem, LCB_F_WRITE);
+
for (;;) {
if (rwsem_try_write_lock(sem, &waiter)) {
/* rwsem_try_write_lock() implies ACQUIRE on success */
@@ -1148,17 +1196,15 @@ trylock_again:
__set_current_state(TASK_RUNNING);
raw_spin_unlock_irq(&sem->wait_lock);
lockevent_inc(rwsem_wlock);
+ trace_contention_end(sem, 0);
return sem;
out_nolock:
__set_current_state(TASK_RUNNING);
raw_spin_lock_irq(&sem->wait_lock);
- rwsem_del_waiter(sem, &waiter);
- if (!list_empty(&sem->wait_list))
- rwsem_mark_wake(sem, RWSEM_WAKE_ANY, &wake_q);
- raw_spin_unlock_irq(&sem->wait_lock);
- wake_up_q(&wake_q);
+ rwsem_del_wake_waiter(sem, &waiter, &wake_q);
lockevent_inc(rwsem_wlock_fail);
+ trace_contention_end(sem, -EINTR);
return ERR_PTR(-EINTR);
}
@@ -1314,8 +1360,10 @@ static inline void __up_write(struct rw_semaphore *sem)
DEBUG_RWSEMS_WARN_ON((rwsem_owner(sem) != current) &&
!rwsem_test_oflags(sem, RWSEM_NONSPINNABLE), sem);
+ preempt_disable();
rwsem_clear_owner(sem);
tmp = atomic_long_fetch_add_release(-RWSEM_WRITER_LOCKED, &sem->count);
+ preempt_enable();
if (unlikely(tmp & RWSEM_FLAG_WAITERS))
rwsem_wake(sem);
}
diff --git a/kernel/locking/semaphore.c b/kernel/locking/semaphore.c
index 9ee381e4d2a4..34bfae72f295 100644
--- a/kernel/locking/semaphore.c
+++ b/kernel/locking/semaphore.c
@@ -32,6 +32,7 @@
#include <linux/semaphore.h>
#include <linux/spinlock.h>
#include <linux/ftrace.h>
+#include <trace/events/lock.h>
static noinline void __down(struct semaphore *sem);
static noinline int __down_interruptible(struct semaphore *sem);
@@ -50,7 +51,7 @@ static noinline void __up(struct semaphore *sem);
* Use of this function is deprecated, please use down_interruptible() or
* down_killable() instead.
*/
-void down(struct semaphore *sem)
+void __sched down(struct semaphore *sem)
{
unsigned long flags;
@@ -73,7 +74,7 @@ EXPORT_SYMBOL(down);
* If the sleep is interrupted by a signal, this function will return -EINTR.
* If the semaphore is successfully acquired, this function returns 0.
*/
-int down_interruptible(struct semaphore *sem)
+int __sched down_interruptible(struct semaphore *sem)
{
unsigned long flags;
int result = 0;
@@ -100,7 +101,7 @@ EXPORT_SYMBOL(down_interruptible);
* -EINTR. If the semaphore is successfully acquired, this function returns
* 0.
*/
-int down_killable(struct semaphore *sem)
+int __sched down_killable(struct semaphore *sem)
{
unsigned long flags;
int result = 0;
@@ -130,7 +131,7 @@ EXPORT_SYMBOL(down_killable);
* Unlike mutex_trylock, this function can be used from interrupt context,
* and the semaphore can be released by any task or interrupt.
*/
-int down_trylock(struct semaphore *sem)
+int __sched down_trylock(struct semaphore *sem)
{
unsigned long flags;
int count;
@@ -155,7 +156,7 @@ EXPORT_SYMBOL(down_trylock);
* If the semaphore is not released within the specified number of jiffies,
* this function returns -ETIME. It returns 0 if the semaphore was acquired.
*/
-int down_timeout(struct semaphore *sem, long timeout)
+int __sched down_timeout(struct semaphore *sem, long timeout)
{
unsigned long flags;
int result = 0;
@@ -179,7 +180,7 @@ EXPORT_SYMBOL(down_timeout);
* Release the semaphore. Unlike mutexes, up() may be called from any
* context and even by tasks which have never called down().
*/
-void up(struct semaphore *sem)
+void __sched up(struct semaphore *sem)
{
unsigned long flags;
@@ -205,7 +206,7 @@ struct semaphore_waiter {
* constant, and thus optimised away by the compiler. Likewise the
* 'timeout' parameter for the cases without timeouts.
*/
-static inline int __sched __down_common(struct semaphore *sem, long state,
+static inline int __sched ___down_common(struct semaphore *sem, long state,
long timeout)
{
struct semaphore_waiter waiter;
@@ -236,6 +237,18 @@ static inline int __sched __down_common(struct semaphore *sem, long state,
return -EINTR;
}
+static inline int __sched __down_common(struct semaphore *sem, long state,
+ long timeout)
+{
+ int ret;
+
+ trace_contention_begin(sem, 0);
+ ret = ___down_common(sem, state, timeout);
+ trace_contention_end(sem, ret);
+
+ return ret;
+}
+
static noinline void __sched __down(struct semaphore *sem)
{
__down_common(sem, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
diff --git a/kernel/locking/spinlock.c b/kernel/locking/spinlock.c
index b562f9289372..8475a0794f8c 100644
--- a/kernel/locking/spinlock.c
+++ b/kernel/locking/spinlock.c
@@ -133,7 +133,7 @@ BUILD_LOCK_OPS(write, rwlock);
#endif
#ifndef CONFIG_INLINE_SPIN_TRYLOCK
-int __lockfunc _raw_spin_trylock(raw_spinlock_t *lock)
+noinline int __lockfunc _raw_spin_trylock(raw_spinlock_t *lock)
{
return __raw_spin_trylock(lock);
}
@@ -141,7 +141,7 @@ EXPORT_SYMBOL(_raw_spin_trylock);
#endif
#ifndef CONFIG_INLINE_SPIN_TRYLOCK_BH
-int __lockfunc _raw_spin_trylock_bh(raw_spinlock_t *lock)
+noinline int __lockfunc _raw_spin_trylock_bh(raw_spinlock_t *lock)
{
return __raw_spin_trylock_bh(lock);
}
@@ -149,7 +149,7 @@ EXPORT_SYMBOL(_raw_spin_trylock_bh);
#endif
#ifndef CONFIG_INLINE_SPIN_LOCK
-void __lockfunc _raw_spin_lock(raw_spinlock_t *lock)
+noinline void __lockfunc _raw_spin_lock(raw_spinlock_t *lock)
{
__raw_spin_lock(lock);
}
@@ -157,7 +157,7 @@ EXPORT_SYMBOL(_raw_spin_lock);
#endif
#ifndef CONFIG_INLINE_SPIN_LOCK_IRQSAVE
-unsigned long __lockfunc _raw_spin_lock_irqsave(raw_spinlock_t *lock)
+noinline unsigned long __lockfunc _raw_spin_lock_irqsave(raw_spinlock_t *lock)
{
return __raw_spin_lock_irqsave(lock);
}
@@ -165,7 +165,7 @@ EXPORT_SYMBOL(_raw_spin_lock_irqsave);
#endif
#ifndef CONFIG_INLINE_SPIN_LOCK_IRQ
-void __lockfunc _raw_spin_lock_irq(raw_spinlock_t *lock)
+noinline void __lockfunc _raw_spin_lock_irq(raw_spinlock_t *lock)
{
__raw_spin_lock_irq(lock);
}
@@ -173,7 +173,7 @@ EXPORT_SYMBOL(_raw_spin_lock_irq);
#endif
#ifndef CONFIG_INLINE_SPIN_LOCK_BH
-void __lockfunc _raw_spin_lock_bh(raw_spinlock_t *lock)
+noinline void __lockfunc _raw_spin_lock_bh(raw_spinlock_t *lock)
{
__raw_spin_lock_bh(lock);
}
@@ -181,7 +181,7 @@ EXPORT_SYMBOL(_raw_spin_lock_bh);
#endif
#ifdef CONFIG_UNINLINE_SPIN_UNLOCK
-void __lockfunc _raw_spin_unlock(raw_spinlock_t *lock)
+noinline void __lockfunc _raw_spin_unlock(raw_spinlock_t *lock)
{
__raw_spin_unlock(lock);
}
@@ -189,7 +189,7 @@ EXPORT_SYMBOL(_raw_spin_unlock);
#endif
#ifndef CONFIG_INLINE_SPIN_UNLOCK_IRQRESTORE
-void __lockfunc _raw_spin_unlock_irqrestore(raw_spinlock_t *lock, unsigned long flags)
+noinline void __lockfunc _raw_spin_unlock_irqrestore(raw_spinlock_t *lock, unsigned long flags)
{
__raw_spin_unlock_irqrestore(lock, flags);
}
@@ -197,7 +197,7 @@ EXPORT_SYMBOL(_raw_spin_unlock_irqrestore);
#endif
#ifndef CONFIG_INLINE_SPIN_UNLOCK_IRQ
-void __lockfunc _raw_spin_unlock_irq(raw_spinlock_t *lock)
+noinline void __lockfunc _raw_spin_unlock_irq(raw_spinlock_t *lock)
{
__raw_spin_unlock_irq(lock);
}
@@ -205,7 +205,7 @@ EXPORT_SYMBOL(_raw_spin_unlock_irq);
#endif
#ifndef CONFIG_INLINE_SPIN_UNLOCK_BH
-void __lockfunc _raw_spin_unlock_bh(raw_spinlock_t *lock)
+noinline void __lockfunc _raw_spin_unlock_bh(raw_spinlock_t *lock)
{
__raw_spin_unlock_bh(lock);
}
@@ -215,7 +215,7 @@ EXPORT_SYMBOL(_raw_spin_unlock_bh);
#ifndef CONFIG_PREEMPT_RT
#ifndef CONFIG_INLINE_READ_TRYLOCK
-int __lockfunc _raw_read_trylock(rwlock_t *lock)
+noinline int __lockfunc _raw_read_trylock(rwlock_t *lock)
{
return __raw_read_trylock(lock);
}
@@ -223,7 +223,7 @@ EXPORT_SYMBOL(_raw_read_trylock);
#endif
#ifndef CONFIG_INLINE_READ_LOCK
-void __lockfunc _raw_read_lock(rwlock_t *lock)
+noinline void __lockfunc _raw_read_lock(rwlock_t *lock)
{
__raw_read_lock(lock);
}
@@ -231,7 +231,7 @@ EXPORT_SYMBOL(_raw_read_lock);
#endif
#ifndef CONFIG_INLINE_READ_LOCK_IRQSAVE
-unsigned long __lockfunc _raw_read_lock_irqsave(rwlock_t *lock)
+noinline unsigned long __lockfunc _raw_read_lock_irqsave(rwlock_t *lock)
{
return __raw_read_lock_irqsave(lock);
}
@@ -239,7 +239,7 @@ EXPORT_SYMBOL(_raw_read_lock_irqsave);
#endif
#ifndef CONFIG_INLINE_READ_LOCK_IRQ
-void __lockfunc _raw_read_lock_irq(rwlock_t *lock)
+noinline void __lockfunc _raw_read_lock_irq(rwlock_t *lock)
{
__raw_read_lock_irq(lock);
}
@@ -247,7 +247,7 @@ EXPORT_SYMBOL(_raw_read_lock_irq);
#endif
#ifndef CONFIG_INLINE_READ_LOCK_BH
-void __lockfunc _raw_read_lock_bh(rwlock_t *lock)
+noinline void __lockfunc _raw_read_lock_bh(rwlock_t *lock)
{
__raw_read_lock_bh(lock);
}
@@ -255,7 +255,7 @@ EXPORT_SYMBOL(_raw_read_lock_bh);
#endif
#ifndef CONFIG_INLINE_READ_UNLOCK
-void __lockfunc _raw_read_unlock(rwlock_t *lock)
+noinline void __lockfunc _raw_read_unlock(rwlock_t *lock)
{
__raw_read_unlock(lock);
}
@@ -263,7 +263,7 @@ EXPORT_SYMBOL(_raw_read_unlock);
#endif
#ifndef CONFIG_INLINE_READ_UNLOCK_IRQRESTORE
-void __lockfunc _raw_read_unlock_irqrestore(rwlock_t *lock, unsigned long flags)
+noinline void __lockfunc _raw_read_unlock_irqrestore(rwlock_t *lock, unsigned long flags)
{
__raw_read_unlock_irqrestore(lock, flags);
}
@@ -271,7 +271,7 @@ EXPORT_SYMBOL(_raw_read_unlock_irqrestore);
#endif
#ifndef CONFIG_INLINE_READ_UNLOCK_IRQ
-void __lockfunc _raw_read_unlock_irq(rwlock_t *lock)
+noinline void __lockfunc _raw_read_unlock_irq(rwlock_t *lock)
{
__raw_read_unlock_irq(lock);
}
@@ -279,7 +279,7 @@ EXPORT_SYMBOL(_raw_read_unlock_irq);
#endif
#ifndef CONFIG_INLINE_READ_UNLOCK_BH
-void __lockfunc _raw_read_unlock_bh(rwlock_t *lock)
+noinline void __lockfunc _raw_read_unlock_bh(rwlock_t *lock)
{
__raw_read_unlock_bh(lock);
}
@@ -287,7 +287,7 @@ EXPORT_SYMBOL(_raw_read_unlock_bh);
#endif
#ifndef CONFIG_INLINE_WRITE_TRYLOCK
-int __lockfunc _raw_write_trylock(rwlock_t *lock)
+noinline int __lockfunc _raw_write_trylock(rwlock_t *lock)
{
return __raw_write_trylock(lock);
}
@@ -295,15 +295,25 @@ EXPORT_SYMBOL(_raw_write_trylock);
#endif
#ifndef CONFIG_INLINE_WRITE_LOCK
-void __lockfunc _raw_write_lock(rwlock_t *lock)
+noinline void __lockfunc _raw_write_lock(rwlock_t *lock)
{
__raw_write_lock(lock);
}
EXPORT_SYMBOL(_raw_write_lock);
+
+#ifndef CONFIG_DEBUG_LOCK_ALLOC
+#define __raw_write_lock_nested(lock, subclass) __raw_write_lock(((void)(subclass), (lock)))
+#endif
+
+void __lockfunc _raw_write_lock_nested(rwlock_t *lock, int subclass)
+{
+ __raw_write_lock_nested(lock, subclass);
+}
+EXPORT_SYMBOL(_raw_write_lock_nested);
#endif
#ifndef CONFIG_INLINE_WRITE_LOCK_IRQSAVE
-unsigned long __lockfunc _raw_write_lock_irqsave(rwlock_t *lock)
+noinline unsigned long __lockfunc _raw_write_lock_irqsave(rwlock_t *lock)
{
return __raw_write_lock_irqsave(lock);
}
@@ -311,7 +321,7 @@ EXPORT_SYMBOL(_raw_write_lock_irqsave);
#endif
#ifndef CONFIG_INLINE_WRITE_LOCK_IRQ
-void __lockfunc _raw_write_lock_irq(rwlock_t *lock)
+noinline void __lockfunc _raw_write_lock_irq(rwlock_t *lock)
{
__raw_write_lock_irq(lock);
}
@@ -319,7 +329,7 @@ EXPORT_SYMBOL(_raw_write_lock_irq);
#endif
#ifndef CONFIG_INLINE_WRITE_LOCK_BH
-void __lockfunc _raw_write_lock_bh(rwlock_t *lock)
+noinline void __lockfunc _raw_write_lock_bh(rwlock_t *lock)
{
__raw_write_lock_bh(lock);
}
@@ -327,7 +337,7 @@ EXPORT_SYMBOL(_raw_write_lock_bh);
#endif
#ifndef CONFIG_INLINE_WRITE_UNLOCK
-void __lockfunc _raw_write_unlock(rwlock_t *lock)
+noinline void __lockfunc _raw_write_unlock(rwlock_t *lock)
{
__raw_write_unlock(lock);
}
@@ -335,7 +345,7 @@ EXPORT_SYMBOL(_raw_write_unlock);
#endif
#ifndef CONFIG_INLINE_WRITE_UNLOCK_IRQRESTORE
-void __lockfunc _raw_write_unlock_irqrestore(rwlock_t *lock, unsigned long flags)
+noinline void __lockfunc _raw_write_unlock_irqrestore(rwlock_t *lock, unsigned long flags)
{
__raw_write_unlock_irqrestore(lock, flags);
}
@@ -343,7 +353,7 @@ EXPORT_SYMBOL(_raw_write_unlock_irqrestore);
#endif
#ifndef CONFIG_INLINE_WRITE_UNLOCK_IRQ
-void __lockfunc _raw_write_unlock_irq(rwlock_t *lock)
+noinline void __lockfunc _raw_write_unlock_irq(rwlock_t *lock)
{
__raw_write_unlock_irq(lock);
}
@@ -351,7 +361,7 @@ EXPORT_SYMBOL(_raw_write_unlock_irq);
#endif
#ifndef CONFIG_INLINE_WRITE_UNLOCK_BH
-void __lockfunc _raw_write_unlock_bh(rwlock_t *lock)
+noinline void __lockfunc _raw_write_unlock_bh(rwlock_t *lock)
{
__raw_write_unlock_bh(lock);
}
diff --git a/kernel/locking/spinlock_rt.c b/kernel/locking/spinlock_rt.c
index 9e396a09fe0f..48a19ed8486d 100644
--- a/kernel/locking/spinlock_rt.c
+++ b/kernel/locking/spinlock_rt.c
@@ -239,6 +239,18 @@ void __sched rt_write_lock(rwlock_t *rwlock)
}
EXPORT_SYMBOL(rt_write_lock);
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+void __sched rt_write_lock_nested(rwlock_t *rwlock, int subclass)
+{
+ rtlock_might_resched();
+ rwlock_acquire(&rwlock->dep_map, subclass, 0, _RET_IP_);
+ rwbase_write_lock(&rwlock->rwbase, TASK_RTLOCK_WAIT);
+ rcu_read_lock();
+ migrate_disable();
+}
+EXPORT_SYMBOL(rt_write_lock_nested);
+#endif
+
void __sched rt_read_unlock(rwlock_t *rwlock)
{
rwlock_release(&rwlock->dep_map, _RET_IP_);
diff --git a/kernel/locking/test-ww_mutex.c b/kernel/locking/test-ww_mutex.c
index 353004155d65..43efb2a04160 100644
--- a/kernel/locking/test-ww_mutex.c
+++ b/kernel/locking/test-ww_mutex.c
@@ -399,7 +399,7 @@ static int *get_random_order(int count)
order[n] = n;
for (n = count - 1; n > 1; n--) {
- r = get_random_int() % (n + 1);
+ r = prandom_u32_max(n + 1);
if (r != n) {
tmp = order[n];
order[n] = order[r];
@@ -538,7 +538,7 @@ static void stress_one_work(struct work_struct *work)
{
struct stress *stress = container_of(work, typeof(*stress), work);
const int nlocks = stress->nlocks;
- struct ww_mutex *lock = stress->locks + (get_random_int() % nlocks);
+ struct ww_mutex *lock = stress->locks + prandom_u32_max(nlocks);
int err;
do {
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