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authorLinus Torvalds <torvalds@linux-foundation.org>2021-02-21 12:12:01 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2021-02-21 12:12:01 -0800
commit9eef02334505411667a7b51a8f349f8c6c4f3b66 (patch)
tree3a0c8fb85d76595b2f9468d3e31f41147a43ed55 /kernel
parentd089f48fba28db14d0fe7753248f2575a9ddfc73 (diff)
parent3765d01bab73bdb920ef711203978f02cd26e4da (diff)
downloadlinux-9eef02334505411667a7b51a8f349f8c6c4f3b66.tar.gz
Merge tag 'locking-core-2021-02-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar: "Core locking primitives updates: - Remove mutex_trylock_recursive() from the API - no users left - Simplify + constify the futex code a bit Lockdep updates: - Teach lockdep about local_lock_t - Add CONFIG_DEBUG_IRQFLAGS=y debug config option to check for potentially unsafe IRQ mask restoration patterns. (I.e. calling raw_local_irq_restore() with IRQs enabled.) - Add wait context self-tests - Fix graph lock corner case corrupting internal data structures - Fix noinstr annotations LKMM updates: - Simplify the litmus tests - Documentation fixes KCSAN updates: - Re-enable KCSAN instrumentation in lib/random32.c Misc fixes: - Don't branch-trace static label APIs - DocBook fix - Remove stale leftover empty file" * tag 'locking-core-2021-02-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) checkpatch: Don't check for mutex_trylock_recursive() locking/mutex: Kill mutex_trylock_recursive() s390: Use arch_local_irq_{save,restore}() in early boot code lockdep: Noinstr annotate warn_bogus_irq_restore() locking/lockdep: Avoid unmatched unlock locking/rwsem: Remove empty rwsem.h locking/rtmutex: Add missing kernel-doc markup futex: Remove unneeded gotos futex: Change utime parameter to be 'const ... *' lockdep: report broken irq restoration jump_label: Do not profile branch annotations locking: Add Reviewers locking/selftests: Add local_lock inversion tests locking/lockdep: Exclude local_lock_t from IRQ inversions locking/lockdep: Clean up check_redundant() a bit locking/lockdep: Add a skip() function to __bfs() locking/lockdep: Mark local_lock_t locking/selftests: More granular debug_locks_verbose lockdep/selftest: Add wait context selftests tools/memory-model: Fix typo in klitmus7 compatibility table ...
Diffstat (limited to 'kernel')
-rw-r--r--kernel/futex.c13
-rw-r--r--kernel/kcsan/core.c26
-rw-r--r--kernel/locking/Makefile1
-rw-r--r--kernel/locking/irqflag-debug.c13
-rw-r--r--kernel/locking/lockdep.c186
-rw-r--r--kernel/locking/mutex.c10
-rw-r--r--kernel/locking/rtmutex.c17
-rw-r--r--kernel/locking/rwsem.h0
8 files changed, 171 insertions, 95 deletions
diff --git a/kernel/futex.c b/kernel/futex.c
index 45a13eb8894e..e68db7745039 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -3012,7 +3012,7 @@ retry:
* Success, we're done! No tricky corner cases.
*/
if (!ret)
- goto out_putkey;
+ return ret;
/*
* The atomic access to the futex value generated a
* pagefault, so retry the user-access and the wakeup:
@@ -3029,7 +3029,7 @@ retry:
* wake_futex_pi has detected invalid state. Tell user
* space.
*/
- goto out_putkey;
+ return ret;
}
/*
@@ -3050,7 +3050,7 @@ retry:
default:
WARN_ON_ONCE(1);
- goto out_putkey;
+ return ret;
}
}
@@ -3061,7 +3061,6 @@ retry:
out_unlock:
spin_unlock(&hb->lock);
-out_putkey:
return ret;
pi_retry:
@@ -3763,8 +3762,8 @@ long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout,
SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val,
- struct __kernel_timespec __user *, utime, u32 __user *, uaddr2,
- u32, val3)
+ const struct __kernel_timespec __user *, utime,
+ u32 __user *, uaddr2, u32, val3)
{
struct timespec64 ts;
ktime_t t, *tp = NULL;
@@ -3959,7 +3958,7 @@ err_unlock:
#ifdef CONFIG_COMPAT_32BIT_TIME
SYSCALL_DEFINE6(futex_time32, u32 __user *, uaddr, int, op, u32, val,
- struct old_timespec32 __user *, utime, u32 __user *, uaddr2,
+ const struct old_timespec32 __user *, utime, u32 __user *, uaddr2,
u32, val3)
{
struct timespec64 ts;
diff --git a/kernel/kcsan/core.c b/kernel/kcsan/core.c
index 3994a217bde7..3bf98db9c702 100644
--- a/kernel/kcsan/core.c
+++ b/kernel/kcsan/core.c
@@ -12,7 +12,6 @@
#include <linux/moduleparam.h>
#include <linux/percpu.h>
#include <linux/preempt.h>
-#include <linux/random.h>
#include <linux/sched.h>
#include <linux/uaccess.h>
@@ -101,7 +100,7 @@ static atomic_long_t watchpoints[CONFIG_KCSAN_NUM_WATCHPOINTS + NUM_SLOTS-1];
static DEFINE_PER_CPU(long, kcsan_skip);
/* For kcsan_prandom_u32_max(). */
-static DEFINE_PER_CPU(struct rnd_state, kcsan_rand_state);
+static DEFINE_PER_CPU(u32, kcsan_rand_state);
static __always_inline atomic_long_t *find_watchpoint(unsigned long addr,
size_t size,
@@ -275,20 +274,17 @@ should_watch(const volatile void *ptr, size_t size, int type, struct kcsan_ctx *
}
/*
- * Returns a pseudo-random number in interval [0, ep_ro). See prandom_u32_max()
- * for more details.
- *
- * The open-coded version here is using only safe primitives for all contexts
- * where we can have KCSAN instrumentation. In particular, we cannot use
- * prandom_u32() directly, as its tracepoint could cause recursion.
+ * Returns a pseudo-random number in interval [0, ep_ro). Simple linear
+ * congruential generator, using constants from "Numerical Recipes".
*/
static u32 kcsan_prandom_u32_max(u32 ep_ro)
{
- struct rnd_state *state = &get_cpu_var(kcsan_rand_state);
- const u32 res = prandom_u32_state(state);
+ u32 state = this_cpu_read(kcsan_rand_state);
+
+ state = 1664525 * state + 1013904223;
+ this_cpu_write(kcsan_rand_state, state);
- put_cpu_var(kcsan_rand_state);
- return (u32)(((u64) res * ep_ro) >> 32);
+ return state % ep_ro;
}
static inline void reset_kcsan_skip(void)
@@ -639,10 +635,14 @@ static __always_inline void check_access(const volatile void *ptr, size_t size,
void __init kcsan_init(void)
{
+ int cpu;
+
BUG_ON(!in_task());
kcsan_debugfs_init();
- prandom_seed_full_state(&kcsan_rand_state);
+
+ for_each_possible_cpu(cpu)
+ per_cpu(kcsan_rand_state, cpu) = (u32)get_cycles();
/*
* We are in the init task, and no other tasks should be running;
diff --git a/kernel/locking/Makefile b/kernel/locking/Makefile
index 6d11cfb9b41f..8838f1d7c4a2 100644
--- a/kernel/locking/Makefile
+++ b/kernel/locking/Makefile
@@ -15,6 +15,7 @@ CFLAGS_REMOVE_mutex-debug.o = $(CC_FLAGS_FTRACE)
CFLAGS_REMOVE_rtmutex-debug.o = $(CC_FLAGS_FTRACE)
endif
+obj-$(CONFIG_DEBUG_IRQFLAGS) += irqflag-debug.o
obj-$(CONFIG_DEBUG_MUTEXES) += mutex-debug.o
obj-$(CONFIG_LOCKDEP) += lockdep.o
ifeq ($(CONFIG_PROC_FS),y)
diff --git a/kernel/locking/irqflag-debug.c b/kernel/locking/irqflag-debug.c
new file mode 100644
index 000000000000..810b50344d35
--- /dev/null
+++ b/kernel/locking/irqflag-debug.c
@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/bug.h>
+#include <linux/export.h>
+#include <linux/irqflags.h>
+
+noinstr void warn_bogus_irq_restore(void)
+{
+ instrumentation_begin();
+ WARN_ONCE(1, "raw_local_irq_restore() called with IRQs enabled\n");
+ instrumentation_end();
+}
+EXPORT_SYMBOL(warn_bogus_irq_restore);
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index bdaf4829098c..c6d0c1dc6253 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -1290,6 +1290,7 @@ register_lock_class(struct lockdep_map *lock, unsigned int subclass, int force)
class->name_version = count_matching_names(class);
class->wait_type_inner = lock->wait_type_inner;
class->wait_type_outer = lock->wait_type_outer;
+ class->lock_type = lock->lock_type;
/*
* We use RCU's safe list-add method to make
* parallel walking of the hash-list safe:
@@ -1671,6 +1672,7 @@ static inline struct lock_list *__bfs_next(struct lock_list *lock, int offset)
static enum bfs_result __bfs(struct lock_list *source_entry,
void *data,
bool (*match)(struct lock_list *entry, void *data),
+ bool (*skip)(struct lock_list *entry, void *data),
struct lock_list **target_entry,
int offset)
{
@@ -1731,7 +1733,12 @@ static enum bfs_result __bfs(struct lock_list *source_entry,
/*
* Step 3: we haven't visited this and there is a strong
* dependency path to this, so check with @match.
+ * If @skip is provide and returns true, we skip this
+ * lock (and any path this lock is in).
*/
+ if (skip && skip(lock, data))
+ continue;
+
if (match(lock, data)) {
*target_entry = lock;
return BFS_RMATCH;
@@ -1774,9 +1781,10 @@ static inline enum bfs_result
__bfs_forwards(struct lock_list *src_entry,
void *data,
bool (*match)(struct lock_list *entry, void *data),
+ bool (*skip)(struct lock_list *entry, void *data),
struct lock_list **target_entry)
{
- return __bfs(src_entry, data, match, target_entry,
+ return __bfs(src_entry, data, match, skip, target_entry,
offsetof(struct lock_class, locks_after));
}
@@ -1785,9 +1793,10 @@ static inline enum bfs_result
__bfs_backwards(struct lock_list *src_entry,
void *data,
bool (*match)(struct lock_list *entry, void *data),
+ bool (*skip)(struct lock_list *entry, void *data),
struct lock_list **target_entry)
{
- return __bfs(src_entry, data, match, target_entry,
+ return __bfs(src_entry, data, match, skip, target_entry,
offsetof(struct lock_class, locks_before));
}
@@ -2018,7 +2027,7 @@ static unsigned long __lockdep_count_forward_deps(struct lock_list *this)
unsigned long count = 0;
struct lock_list *target_entry;
- __bfs_forwards(this, (void *)&count, noop_count, &target_entry);
+ __bfs_forwards(this, (void *)&count, noop_count, NULL, &target_entry);
return count;
}
@@ -2043,7 +2052,7 @@ static unsigned long __lockdep_count_backward_deps(struct lock_list *this)
unsigned long count = 0;
struct lock_list *target_entry;
- __bfs_backwards(this, (void *)&count, noop_count, &target_entry);
+ __bfs_backwards(this, (void *)&count, noop_count, NULL, &target_entry);
return count;
}
@@ -2071,11 +2080,12 @@ unsigned long lockdep_count_backward_deps(struct lock_class *class)
static noinline enum bfs_result
check_path(struct held_lock *target, struct lock_list *src_entry,
bool (*match)(struct lock_list *entry, void *data),
+ bool (*skip)(struct lock_list *entry, void *data),
struct lock_list **target_entry)
{
enum bfs_result ret;
- ret = __bfs_forwards(src_entry, target, match, target_entry);
+ ret = __bfs_forwards(src_entry, target, match, skip, target_entry);
if (unlikely(bfs_error(ret)))
print_bfs_bug(ret);
@@ -2102,7 +2112,7 @@ check_noncircular(struct held_lock *src, struct held_lock *target,
debug_atomic_inc(nr_cyclic_checks);
- ret = check_path(target, &src_entry, hlock_conflict, &target_entry);
+ ret = check_path(target, &src_entry, hlock_conflict, NULL, &target_entry);
if (unlikely(ret == BFS_RMATCH)) {
if (!*trace) {
@@ -2120,46 +2130,6 @@ check_noncircular(struct held_lock *src, struct held_lock *target,
return ret;
}
-#ifdef CONFIG_LOCKDEP_SMALL
-/*
- * Check that the dependency graph starting at <src> can lead to
- * <target> or not. If it can, <src> -> <target> dependency is already
- * in the graph.
- *
- * Return BFS_RMATCH if it does, or BFS_RMATCH if it does not, return BFS_E* if
- * any error appears in the bfs search.
- */
-static noinline enum bfs_result
-check_redundant(struct held_lock *src, struct held_lock *target)
-{
- enum bfs_result ret;
- struct lock_list *target_entry;
- struct lock_list src_entry;
-
- bfs_init_root(&src_entry, src);
- /*
- * Special setup for check_redundant().
- *
- * To report redundant, we need to find a strong dependency path that
- * is equal to or stronger than <src> -> <target>. So if <src> is E,
- * we need to let __bfs() only search for a path starting at a -(E*)->,
- * we achieve this by setting the initial node's ->only_xr to true in
- * that case. And if <prev> is S, we set initial ->only_xr to false
- * because both -(S*)-> (equal) and -(E*)-> (stronger) are redundant.
- */
- src_entry.only_xr = src->read == 0;
-
- debug_atomic_inc(nr_redundant_checks);
-
- ret = check_path(target, &src_entry, hlock_equal, &target_entry);
-
- if (ret == BFS_RMATCH)
- debug_atomic_inc(nr_redundant);
-
- return ret;
-}
-#endif
-
#ifdef CONFIG_TRACE_IRQFLAGS
/*
@@ -2230,6 +2200,44 @@ static inline bool usage_match(struct lock_list *entry, void *mask)
return !!((entry->class->usage_mask & LOCKF_IRQ) & *(unsigned long *)mask);
}
+static inline bool usage_skip(struct lock_list *entry, void *mask)
+{
+ /*
+ * Skip local_lock() for irq inversion detection.
+ *
+ * For !RT, local_lock() is not a real lock, so it won't carry any
+ * dependency.
+ *
+ * For RT, an irq inversion happens when we have lock A and B, and on
+ * some CPU we can have:
+ *
+ * lock(A);
+ * <interrupted>
+ * lock(B);
+ *
+ * where lock(B) cannot sleep, and we have a dependency B -> ... -> A.
+ *
+ * Now we prove local_lock() cannot exist in that dependency. First we
+ * have the observation for any lock chain L1 -> ... -> Ln, for any
+ * 1 <= i <= n, Li.inner_wait_type <= L1.inner_wait_type, otherwise
+ * wait context check will complain. And since B is not a sleep lock,
+ * therefore B.inner_wait_type >= 2, and since the inner_wait_type of
+ * local_lock() is 3, which is greater than 2, therefore there is no
+ * way the local_lock() exists in the dependency B -> ... -> A.
+ *
+ * As a result, we will skip local_lock(), when we search for irq
+ * inversion bugs.
+ */
+ if (entry->class->lock_type == LD_LOCK_PERCPU) {
+ if (DEBUG_LOCKS_WARN_ON(entry->class->wait_type_inner < LD_WAIT_CONFIG))
+ return false;
+
+ return true;
+ }
+
+ return false;
+}
+
/*
* Find a node in the forwards-direction dependency sub-graph starting
* at @root->class that matches @bit.
@@ -2245,7 +2253,7 @@ find_usage_forwards(struct lock_list *root, unsigned long usage_mask,
debug_atomic_inc(nr_find_usage_forwards_checks);
- result = __bfs_forwards(root, &usage_mask, usage_match, target_entry);
+ result = __bfs_forwards(root, &usage_mask, usage_match, usage_skip, target_entry);
return result;
}
@@ -2262,7 +2270,7 @@ find_usage_backwards(struct lock_list *root, unsigned long usage_mask,
debug_atomic_inc(nr_find_usage_backwards_checks);
- result = __bfs_backwards(root, &usage_mask, usage_match, target_entry);
+ result = __bfs_backwards(root, &usage_mask, usage_match, usage_skip, target_entry);
return result;
}
@@ -2627,7 +2635,7 @@ static int check_irq_usage(struct task_struct *curr, struct held_lock *prev,
*/
bfs_init_rootb(&this, prev);
- ret = __bfs_backwards(&this, &usage_mask, usage_accumulate, NULL);
+ ret = __bfs_backwards(&this, &usage_mask, usage_accumulate, usage_skip, NULL);
if (bfs_error(ret)) {
print_bfs_bug(ret);
return 0;
@@ -2694,8 +2702,68 @@ static inline int check_irq_usage(struct task_struct *curr,
{
return 1;
}
+
+static inline bool usage_skip(struct lock_list *entry, void *mask)
+{
+ return false;
+}
+
#endif /* CONFIG_TRACE_IRQFLAGS */
+#ifdef CONFIG_LOCKDEP_SMALL
+/*
+ * Check that the dependency graph starting at <src> can lead to
+ * <target> or not. If it can, <src> -> <target> dependency is already
+ * in the graph.
+ *
+ * Return BFS_RMATCH if it does, or BFS_RMATCH if it does not, return BFS_E* if
+ * any error appears in the bfs search.
+ */
+static noinline enum bfs_result
+check_redundant(struct held_lock *src, struct held_lock *target)
+{
+ enum bfs_result ret;
+ struct lock_list *target_entry;
+ struct lock_list src_entry;
+
+ bfs_init_root(&src_entry, src);
+ /*
+ * Special setup for check_redundant().
+ *
+ * To report redundant, we need to find a strong dependency path that
+ * is equal to or stronger than <src> -> <target>. So if <src> is E,
+ * we need to let __bfs() only search for a path starting at a -(E*)->,
+ * we achieve this by setting the initial node's ->only_xr to true in
+ * that case. And if <prev> is S, we set initial ->only_xr to false
+ * because both -(S*)-> (equal) and -(E*)-> (stronger) are redundant.
+ */
+ src_entry.only_xr = src->read == 0;
+
+ debug_atomic_inc(nr_redundant_checks);
+
+ /*
+ * Note: we skip local_lock() for redundant check, because as the
+ * comment in usage_skip(), A -> local_lock() -> B and A -> B are not
+ * the same.
+ */
+ ret = check_path(target, &src_entry, hlock_equal, usage_skip, &target_entry);
+
+ if (ret == BFS_RMATCH)
+ debug_atomic_inc(nr_redundant);
+
+ return ret;
+}
+
+#else
+
+static inline enum bfs_result
+check_redundant(struct held_lock *src, struct held_lock *target)
+{
+ return BFS_RNOMATCH;
+}
+
+#endif
+
static void inc_chains(int irq_context)
{
if (irq_context & LOCK_CHAIN_HARDIRQ_CONTEXT)
@@ -2916,7 +2984,6 @@ check_prev_add(struct task_struct *curr, struct held_lock *prev,
}
}
-#ifdef CONFIG_LOCKDEP_SMALL
/*
* Is the <prev> -> <next> link redundant?
*/
@@ -2925,7 +2992,6 @@ check_prev_add(struct task_struct *curr, struct held_lock *prev,
return 0;
else if (ret == BFS_RMATCH)
return 2;
-#endif
if (!*trace) {
*trace = save_trace();
@@ -3707,7 +3773,7 @@ static void
print_usage_bug(struct task_struct *curr, struct held_lock *this,
enum lock_usage_bit prev_bit, enum lock_usage_bit new_bit)
{
- if (!debug_locks_off_graph_unlock() || debug_locks_silent)
+ if (!debug_locks_off() || debug_locks_silent)
return;
pr_warn("\n");
@@ -3748,6 +3814,7 @@ valid_state(struct task_struct *curr, struct held_lock *this,
enum lock_usage_bit new_bit, enum lock_usage_bit bad_bit)
{
if (unlikely(hlock_class(this)->usage_mask & (1 << bad_bit))) {
+ graph_unlock();
print_usage_bug(curr, this, bad_bit, new_bit);
return 0;
}
@@ -4503,9 +4570,9 @@ print_lock_invalid_wait_context(struct task_struct *curr,
*/
static int check_wait_context(struct task_struct *curr, struct held_lock *next)
{
- short next_inner = hlock_class(next)->wait_type_inner;
- short next_outer = hlock_class(next)->wait_type_outer;
- short curr_inner;
+ u8 next_inner = hlock_class(next)->wait_type_inner;
+ u8 next_outer = hlock_class(next)->wait_type_outer;
+ u8 curr_inner;
int depth;
if (!curr->lockdep_depth || !next_inner || next->trylock)
@@ -4528,7 +4595,7 @@ static int check_wait_context(struct task_struct *curr, struct held_lock *next)
for (; depth < curr->lockdep_depth; depth++) {
struct held_lock *prev = curr->held_locks + depth;
- short prev_inner = hlock_class(prev)->wait_type_inner;
+ u8 prev_inner = hlock_class(prev)->wait_type_inner;
if (prev_inner) {
/*
@@ -4577,9 +4644,9 @@ static inline int check_wait_context(struct task_struct *curr,
/*
* Initialize a lock instance's lock-class mapping info:
*/
-void lockdep_init_map_waits(struct lockdep_map *lock, const char *name,
+void lockdep_init_map_type(struct lockdep_map *lock, const char *name,
struct lock_class_key *key, int subclass,
- short inner, short outer)
+ u8 inner, u8 outer, u8 lock_type)
{
int i;
@@ -4602,6 +4669,7 @@ void lockdep_init_map_waits(struct lockdep_map *lock, const char *name,
lock->wait_type_outer = outer;
lock->wait_type_inner = inner;
+ lock->lock_type = lock_type;
/*
* No key, no joy, we need to hash something.
@@ -4636,7 +4704,7 @@ void lockdep_init_map_waits(struct lockdep_map *lock, const char *name,
raw_local_irq_restore(flags);
}
}
-EXPORT_SYMBOL_GPL(lockdep_init_map_waits);
+EXPORT_SYMBOL_GPL(lockdep_init_map_type);
struct lock_class_key __lockdep_no_validate__;
EXPORT_SYMBOL_GPL(__lockdep_no_validate__);
diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c
index 5352ce50a97e..adb935090768 100644
--- a/kernel/locking/mutex.c
+++ b/kernel/locking/mutex.c
@@ -86,16 +86,6 @@ bool mutex_is_locked(struct mutex *lock)
}
EXPORT_SYMBOL(mutex_is_locked);
-__must_check enum mutex_trylock_recursive_enum
-mutex_trylock_recursive(struct mutex *lock)
-{
- if (unlikely(__mutex_owner(lock) == current))
- return MUTEX_TRYLOCK_RECURSIVE;
-
- return mutex_trylock(lock);
-}
-EXPORT_SYMBOL(mutex_trylock_recursive);
-
static inline unsigned long __owner_flags(unsigned long owner)
{
return owner & MUTEX_FLAGS;
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index 2f8cd616d3b2..47a6e0b8073d 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -1604,8 +1604,11 @@ void __sched rt_mutex_unlock(struct rt_mutex *lock)
EXPORT_SYMBOL_GPL(rt_mutex_unlock);
/**
- * Futex variant, that since futex variants do not use the fast-path, can be
- * simple and will not need to retry.
+ * __rt_mutex_futex_unlock - Futex variant, that since futex variants
+ * do not use the fast-path, can be simple and will not need to retry.
+ *
+ * @lock: The rt_mutex to be unlocked
+ * @wake_q: The wake queue head from which to get the next lock waiter
*/
bool __sched __rt_mutex_futex_unlock(struct rt_mutex *lock,
struct wake_q_head *wake_q)
@@ -1662,13 +1665,15 @@ void rt_mutex_destroy(struct rt_mutex *lock)
EXPORT_SYMBOL_GPL(rt_mutex_destroy);
/**
- * __rt_mutex_init - initialize the rt lock
+ * __rt_mutex_init - initialize the rt_mutex
*
- * @lock: the rt lock to be initialized
+ * @lock: The rt_mutex to be initialized
+ * @name: The lock name used for debugging
+ * @key: The lock class key used for debugging
*
- * Initialize the rt lock to unlocked state.
+ * Initialize the rt_mutex to unlocked state.
*
- * Initializing of a locked rt lock is not allowed
+ * Initializing of a locked rt_mutex is not allowed
*/
void __rt_mutex_init(struct rt_mutex *lock, const char *name,
struct lock_class_key *key)
diff --git a/kernel/locking/rwsem.h b/kernel/locking/rwsem.h
deleted file mode 100644
index e69de29bb2d1..000000000000
--- a/kernel/locking/rwsem.h
+++ /dev/null