liblockdep: Wrap kernel/locking/lockdep.c to allow usage from userspace

kernel/locking/lockdep.c deals with validating locking scenarios for
various architectures supported by the kernel. There isn't
anything kernel specific going on in lockdep, and when we
compare userspace to other architectures that don't have to deal
with irqs such as s390, they become all too similar.

We wrap kernel/locking/lockdep.c and include/linux/lockdep.h with
several headers which allow us to build and use lockdep from
userspace. We don't touch the kernel code itself which means
that any work done on lockdep in the kernel will automatically
benefit userspace lockdep as well!

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: torvalds@linux-foundation.org
Link: http://lkml.kernel.org/r/1371163284-6346-3-git-send-email-sasha.levin@oracle.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

34 files changed, 431 insertions, 0 deletions

diff --git a/tools/lib/lockdep/uinclude/asm/hweight.h b/tools/lib/lockdep/uinclude/asm/hweight.h
new file mode 100644
index 000000000000..fab00ff936d1
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/asm/hweight.h
@@ -0,0 +1,3 @@
+
+/* empty file */
+
diff --git a/tools/lib/lockdep/uinclude/asm/sections.h b/tools/lib/lockdep/uinclude/asm/sections.h
new file mode 100644
index 000000000000..fab00ff936d1
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/asm/sections.h
@@ -0,0 +1,3 @@
+
+/* empty file */
+
diff --git a/tools/lib/lockdep/uinclude/linux/bitops.h b/tools/lib/lockdep/uinclude/linux/bitops.h
new file mode 100644
index 000000000000..fab00ff936d1
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/bitops.h
@@ -0,0 +1,3 @@
+
+/* empty file */
+
diff --git a/tools/lib/lockdep/uinclude/linux/compiler.h b/tools/lib/lockdep/uinclude/linux/compiler.h
new file mode 100644
index 000000000000..7ac838a1f196
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/compiler.h
@@ -0,0 +1,7 @@
+#ifndef _LIBLOCKDEP_LINUX_COMPILER_H_
+#define _LIBLOCKDEP_LINUX_COMPILER_H_
+
+#define __used          __attribute__((__unused__))
+#define unlikely
+
+#endif
diff --git a/tools/lib/lockdep/uinclude/linux/debug_locks.h b/tools/lib/lockdep/uinclude/linux/debug_locks.h
new file mode 100644
index 000000000000..f38eb64df794
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/debug_locks.h
@@ -0,0 +1,12 @@
+#ifndef _LIBLOCKDEP_DEBUG_LOCKS_H_
+#define _LIBLOCKDEP_DEBUG_LOCKS_H_
+
+#include <stddef.h>
+#include <linux/compiler.h>
+
+#define DEBUG_LOCKS_WARN_ON(x) (x)
+
+extern bool debug_locks;
+extern bool debug_locks_silent;
+
+#endif
diff --git a/tools/lib/lockdep/uinclude/linux/delay.h b/tools/lib/lockdep/uinclude/linux/delay.h
new file mode 100644
index 000000000000..fab00ff936d1
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/delay.h
@@ -0,0 +1,3 @@
+
+/* empty file */
+
diff --git a/tools/lib/lockdep/uinclude/linux/export.h b/tools/lib/lockdep/uinclude/linux/export.h
new file mode 100644
index 000000000000..6bdf3492c535
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/export.h
@@ -0,0 +1,7 @@
+#ifndef _LIBLOCKDEP_LINUX_EXPORT_H_
+#define _LIBLOCKDEP_LINUX_EXPORT_H_
+
+#define EXPORT_SYMBOL(sym)
+#define EXPORT_SYMBOL_GPL(sym)
+
+#endif
diff --git a/tools/lib/lockdep/uinclude/linux/ftrace.h b/tools/lib/lockdep/uinclude/linux/ftrace.h
new file mode 100644
index 000000000000..fab00ff936d1
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/ftrace.h
@@ -0,0 +1,3 @@
+
+/* empty file */
+
diff --git a/tools/lib/lockdep/uinclude/linux/gfp.h b/tools/lib/lockdep/uinclude/linux/gfp.h
new file mode 100644
index 000000000000..fab00ff936d1
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/gfp.h
@@ -0,0 +1,3 @@
+
+/* empty file */
+
diff --git a/tools/lib/lockdep/uinclude/linux/hardirq.h b/tools/lib/lockdep/uinclude/linux/hardirq.h
new file mode 100644
index 000000000000..c8f3f8f58729
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/hardirq.h
@@ -0,0 +1,11 @@
+#ifndef _LIBLOCKDEP_LINUX_HARDIRQ_H_
+#define _LIBLOCKDEP_LINUX_HARDIRQ_H_
+
+#define SOFTIRQ_BITS    0UL
+#define HARDIRQ_BITS    0UL
+#define SOFTIRQ_SHIFT   0UL
+#define HARDIRQ_SHIFT   0UL
+#define hardirq_count() 0UL
+#define softirq_count() 0UL
+
+#endif
diff --git a/tools/lib/lockdep/uinclude/linux/hash.h b/tools/lib/lockdep/uinclude/linux/hash.h
new file mode 100644
index 000000000000..0f8479858dc0
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/hash.h
@@ -0,0 +1 @@
+#include "../../../include/linux/hash.h"
diff --git a/tools/lib/lockdep/uinclude/linux/interrupt.h b/tools/lib/lockdep/uinclude/linux/interrupt.h
new file mode 100644
index 000000000000..fab00ff936d1
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/interrupt.h
@@ -0,0 +1,3 @@
+
+/* empty file */
+
diff --git a/tools/lib/lockdep/uinclude/linux/irqflags.h b/tools/lib/lockdep/uinclude/linux/irqflags.h
new file mode 100644
index 000000000000..6cc296f0fad0
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/irqflags.h
@@ -0,0 +1,38 @@
+#ifndef _LIBLOCKDEP_LINUX_TRACE_IRQFLAGS_H_
+#define _LIBLOCKDEP_LINUX_TRACE_IRQFLAGS_H_
+
+# define trace_hardirq_context(p)       0
+# define trace_softirq_context(p)       0
+# define trace_hardirqs_enabled(p)      0
+# define trace_softirqs_enabled(p)      0
+# define trace_hardirq_enter()          do { } while (0)
+# define trace_hardirq_exit()           do { } while (0)
+# define lockdep_softirq_enter()        do { } while (0)
+# define lockdep_softirq_exit()         do { } while (0)
+# define INIT_TRACE_IRQFLAGS
+
+# define stop_critical_timings() do { } while (0)
+# define start_critical_timings() do { } while (0)
+
+#define raw_local_irq_disable() do { } while (0)
+#define raw_local_irq_enable() do { } while (0)
+#define raw_local_irq_save(flags) ((flags) = 0)
+#define raw_local_irq_restore(flags) do { } while (0)
+#define raw_local_save_flags(flags) ((flags) = 0)
+#define raw_irqs_disabled_flags(flags) do { } while (0)
+#define raw_irqs_disabled() 0
+#define raw_safe_halt()
+
+#define local_irq_enable() do { } while (0)
+#define local_irq_disable() do { } while (0)
+#define local_irq_save(flags) ((flags) = 0)
+#define local_irq_restore(flags) do { } while (0)
+#define local_save_flags(flags) ((flags) = 0)
+#define irqs_disabled() (1)
+#define irqs_disabled_flags(flags) (0)
+#define safe_halt() do { } while (0)
+
+#define trace_lock_release(x, y)
+#define trace_lock_acquire(a, b, c, d, e, f, g)
+
+#endif
diff --git a/tools/lib/lockdep/uinclude/linux/kallsyms.h b/tools/lib/lockdep/uinclude/linux/kallsyms.h
new file mode 100644
index 000000000000..b0f2dbdf1a15
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/kallsyms.h
@@ -0,0 +1,32 @@
+#ifndef _LIBLOCKDEP_LINUX_KALLSYMS_H_
+#define _LIBLOCKDEP_LINUX_KALLSYMS_H_
+
+#include <linux/kernel.h>
+#include <stdio.h>
+
+#define KSYM_NAME_LEN 128
+
+struct module;
+
+static inline const char *kallsyms_lookup(unsigned long addr,
+                                          unsigned long *symbolsize,
+                                          unsigned long *offset,
+                                          char **modname, char *namebuf)
+{
+        return NULL;
+}
+
+#include <execinfo.h>
+#include <stdlib.h>
+static inline void print_ip_sym(unsigned long ip)
+{
+        char **name;
+
+        name = backtrace_symbols((void **)&ip, 1);
+
+        printf("%s\n", *name);
+
+        free(name);
+}
+
+#endif
diff --git a/tools/lib/lockdep/uinclude/linux/kern_levels.h b/tools/lib/lockdep/uinclude/linux/kern_levels.h
new file mode 100644
index 000000000000..3b9bade28698
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/kern_levels.h
@@ -0,0 +1,25 @@
+#ifndef __KERN_LEVELS_H__
+#define __KERN_LEVELS_H__
+
+#define KERN_SOH        ""              /* ASCII Start Of Header */
+#define KERN_SOH_ASCII  ''
+
+#define KERN_EMERG      KERN_SOH ""     /* system is unusable */
+#define KERN_ALERT      KERN_SOH ""     /* action must be taken immediately */
+#define KERN_CRIT       KERN_SOH ""     /* critical conditions */
+#define KERN_ERR        KERN_SOH ""     /* error conditions */
+#define KERN_WARNING    KERN_SOH ""     /* warning conditions */
+#define KERN_NOTICE     KERN_SOH ""     /* normal but significant condition */
+#define KERN_INFO       KERN_SOH ""     /* informational */
+#define KERN_DEBUG      KERN_SOH ""     /* debug-level messages */
+
+#define KERN_DEFAULT    KERN_SOH ""     /* the default kernel loglevel */
+
+/*
+ * Annotation for a "continued" line of log printout (only done after a
+ * line that had no enclosing \n). Only to be used by core/arch code
+ * during early bootup (a continued line is not SMP-safe otherwise).
+ */
+#define KERN_CONT       ""
+
+#endif
diff --git a/tools/lib/lockdep/uinclude/linux/kernel.h b/tools/lib/lockdep/uinclude/linux/kernel.h
new file mode 100644
index 000000000000..a11e3c357be7
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/kernel.h
@@ -0,0 +1,44 @@
+#ifndef _LIBLOCKDEP_LINUX_KERNEL_H_
+#define _LIBLOCKDEP_LINUX_KERNEL_H_
+
+#include <linux/export.h>
+#include <linux/types.h>
+#include <linux/rcu.h>
+#include <linux/hardirq.h>
+#include <linux/kern_levels.h>
+
+#ifndef container_of
+#define container_of(ptr, type, member) ({                      \
+        const typeof(((type *)0)->member) * __mptr = (ptr);     \
+        (type *)((char *)__mptr - offsetof(type, member)); })
+#endif
+
+#define max(x, y) ({                            \
+        typeof(x) _max1 = (x);                  \
+        typeof(y) _max2 = (y);                  \
+        (void) (&_max1 == &_max2);              \
+        _max1 > _max2 ? _max1 : _max2; })
+
+#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
+#define WARN_ON(x) (x)
+#define WARN_ON_ONCE(x) (x)
+#define likely(x) (x)
+#define WARN(x, y, z) (x)
+#define uninitialized_var(x) x
+#define __init
+#define noinline
+#define list_add_tail_rcu list_add_tail
+
+#ifndef CALLER_ADDR0
+#define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
+#endif
+
+#ifndef _RET_IP_
+#define _RET_IP_ CALLER_ADDR0
+#endif
+
+#ifndef _THIS_IP_
+#define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; })
+#endif
+
+#endif
diff --git a/tools/lib/lockdep/uinclude/linux/kmemcheck.h b/tools/lib/lockdep/uinclude/linux/kmemcheck.h
new file mode 100644
index 000000000000..94d598bc6abe
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/kmemcheck.h
@@ -0,0 +1,8 @@
+#ifndef _LIBLOCKDEP_LINUX_KMEMCHECK_H_
+#define _LIBLOCKDEP_LINUX_KMEMCHECK_H_
+
+static inline void kmemcheck_mark_initialized(void *address, unsigned int n)
+{
+}
+
+#endif
diff --git a/tools/lib/lockdep/uinclude/linux/linkage.h b/tools/lib/lockdep/uinclude/linux/linkage.h
new file mode 100644
index 000000000000..fab00ff936d1
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/linkage.h
@@ -0,0 +1,3 @@
+
+/* empty file */
+
diff --git a/tools/lib/lockdep/uinclude/linux/list.h b/tools/lib/lockdep/uinclude/linux/list.h
new file mode 100644
index 000000000000..6e9ef31ed82e
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/list.h
@@ -0,0 +1 @@
+#include "../../../include/linux/list.h"
diff --git a/tools/lib/lockdep/uinclude/linux/lockdep.h b/tools/lib/lockdep/uinclude/linux/lockdep.h
new file mode 100644
index 000000000000..d0f5d6e50214
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/lockdep.h
@@ -0,0 +1,55 @@
+#ifndef _LIBLOCKDEP_LOCKDEP_H_
+#define _LIBLOCKDEP_LOCKDEP_H_
+
+#include <sys/prctl.h>
+#include <sys/syscall.h>
+#include <string.h>
+#include <limits.h>
+#include <linux/utsname.h>
+
+
+#define MAX_LOCK_DEPTH 2000UL
+
+#include "../../../include/linux/lockdep.h"
+
+struct task_struct {
+        u64 curr_chain_key;
+        int lockdep_depth;
+        unsigned int lockdep_recursion;
+        struct held_lock held_locks[MAX_LOCK_DEPTH];
+        gfp_t lockdep_reclaim_gfp;
+        int pid;
+        char comm[17];
+};
+
+extern struct task_struct *__curr(void);
+
+#define current (__curr())
+
+#define debug_locks_off() 1
+#define task_pid_nr(tsk) ((tsk)->pid)
+
+#define KSYM_NAME_LEN 128
+#define printk printf
+
+#define list_del_rcu list_del
+
+#define atomic_t unsigned long
+#define atomic_inc(x) ((*(x))++)
+
+static struct new_utsname *init_utsname(void)
+{
+        static struct new_utsname n = (struct new_utsname) {
+                .release = "liblockdep",
+                .version = LIBLOCKDEP_VERSION,
+        };
+
+        return &n;
+}
+
+#define print_tainted() ""
+#define static_obj(x) 1
+
+#define debug_show_all_locks()
+
+#endif
diff --git a/tools/lib/lockdep/uinclude/linux/module.h b/tools/lib/lockdep/uinclude/linux/module.h
new file mode 100644
index 000000000000..09c7a7be8ccc
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/module.h
@@ -0,0 +1,6 @@
+#ifndef _LIBLOCKDEP_LINUX_MODULE_H_
+#define _LIBLOCKDEP_LINUX_MODULE_H_
+
+#define module_param(name, type, perm)
+
+#endif
diff --git a/tools/lib/lockdep/uinclude/linux/mutex.h b/tools/lib/lockdep/uinclude/linux/mutex.h
new file mode 100644
index 000000000000..fab00ff936d1
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/mutex.h
@@ -0,0 +1,3 @@
+
+/* empty file */
+
diff --git a/tools/lib/lockdep/uinclude/linux/poison.h b/tools/lib/lockdep/uinclude/linux/poison.h
new file mode 100644
index 000000000000..0c27bdf14233
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/poison.h
@@ -0,0 +1 @@
+#include "../../../include/linux/poison.h"
diff --git a/tools/lib/lockdep/uinclude/linux/prefetch.h b/tools/lib/lockdep/uinclude/linux/prefetch.h
new file mode 100644
index 000000000000..d73fe6f850ac
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/prefetch.h
@@ -0,0 +1,6 @@
+#ifndef _LIBLOCKDEP_LINUX_PREFETCH_H_
+#define _LIBLOCKDEP_LINUX_PREFETCH_H
+
+static inline void prefetch(void *a __attribute__((unused))) { }
+
+#endif
diff --git a/tools/lib/lockdep/uinclude/linux/proc_fs.h b/tools/lib/lockdep/uinclude/linux/proc_fs.h
new file mode 100644
index 000000000000..fab00ff936d1
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/proc_fs.h
@@ -0,0 +1,3 @@
+
+/* empty file */
+
diff --git a/tools/lib/lockdep/uinclude/linux/rbtree.h b/tools/lib/lockdep/uinclude/linux/rbtree.h
new file mode 100644
index 000000000000..965901db4862
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/rbtree.h
@@ -0,0 +1 @@
+#include "../../../include/linux/rbtree.h"
diff --git a/tools/lib/lockdep/uinclude/linux/rbtree_augmented.h b/tools/lib/lockdep/uinclude/linux/rbtree_augmented.h
new file mode 100644
index 000000000000..c3759477379c
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/rbtree_augmented.h
@@ -0,0 +1,2 @@
+#define __always_inline
+#include "../../../include/linux/rbtree_augmented.h"
diff --git a/tools/lib/lockdep/uinclude/linux/rcu.h b/tools/lib/lockdep/uinclude/linux/rcu.h
new file mode 100644
index 000000000000..4c99fcb5da27
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/rcu.h
@@ -0,0 +1,16 @@
+#ifndef _LIBLOCKDEP_RCU_H_
+#define _LIBLOCKDEP_RCU_H_
+
+int rcu_scheduler_active;
+
+static inline int rcu_lockdep_current_cpu_online(void)
+{
+        return 1;
+}
+
+static inline int rcu_is_cpu_idle(void)
+{
+        return 1;
+}
+
+#endif
diff --git a/tools/lib/lockdep/uinclude/linux/seq_file.h b/tools/lib/lockdep/uinclude/linux/seq_file.h
new file mode 100644
index 000000000000..fab00ff936d1
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/seq_file.h
@@ -0,0 +1,3 @@
+
+/* empty file */
+
diff --git a/tools/lib/lockdep/uinclude/linux/spinlock.h b/tools/lib/lockdep/uinclude/linux/spinlock.h
new file mode 100644
index 000000000000..68c1aa2bcba5
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/spinlock.h
@@ -0,0 +1,25 @@
+#ifndef _LIBLOCKDEP_SPINLOCK_H_
+#define _LIBLOCKDEP_SPINLOCK_H_
+
+#include <pthread.h>
+#include <stdbool.h>
+
+#define arch_spinlock_t pthread_mutex_t
+#define __ARCH_SPIN_LOCK_UNLOCKED PTHREAD_MUTEX_INITIALIZER
+
+static inline void arch_spin_lock(arch_spinlock_t *mutex)
+{
+        pthread_mutex_lock(mutex);
+}
+
+static inline void arch_spin_unlock(arch_spinlock_t *mutex)
+{
+        pthread_mutex_unlock(mutex);
+}
+
+static inline bool arch_spin_is_locked(arch_spinlock_t *mutex)
+{
+        return true;
+}
+
+#endif
diff --git a/tools/lib/lockdep/uinclude/linux/stacktrace.h b/tools/lib/lockdep/uinclude/linux/stacktrace.h
new file mode 100644
index 000000000000..39aecc6b19d1
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/stacktrace.h
@@ -0,0 +1,32 @@
+#ifndef _LIBLOCKDEP_LINUX_STACKTRACE_H_
+#define _LIBLOCKDEP_LINUX_STACKTRACE_H_
+
+#include <execinfo.h>
+
+struct stack_trace {
+        unsigned int nr_entries, max_entries;
+        unsigned long *entries;
+        int skip;
+};
+
+static inline void print_stack_trace(struct stack_trace *trace, int spaces)
+{
+        backtrace_symbols_fd((void **)trace->entries, trace->nr_entries, 1);
+}
+
+#define save_stack_trace(trace) \
+        ((trace)->nr_entries =  \
+                backtrace((void **)(trace)->entries, (trace)->max_entries))
+
+static inline int dump_stack(void)
+{
+        void *array[64];
+        size_t size;
+
+        size = backtrace(array, 64);
+        backtrace_symbols_fd(array, size, 1);
+
+        return 0;
+}
+
+#endif
diff --git a/tools/lib/lockdep/uinclude/linux/stringify.h b/tools/lib/lockdep/uinclude/linux/stringify.h
new file mode 100644
index 000000000000..05dfcd1ac118
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/stringify.h
@@ -0,0 +1,7 @@
+#ifndef _LIBLOCKDEP_LINUX_STRINGIFY_H_
+#define _LIBLOCKDEP_LINUX_STRINGIFY_H_
+
+#define __stringify_1(x...)     #x
+#define __stringify(x...)       __stringify_1(x)
+
+#endif
diff --git a/tools/lib/lockdep/uinclude/linux/types.h b/tools/lib/lockdep/uinclude/linux/types.h
new file mode 100644
index 000000000000..929938f426de
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/linux/types.h
@@ -0,0 +1,58 @@
+#ifndef _LIBLOCKDEP_LINUX_TYPES_H_
+#define _LIBLOCKDEP_LINUX_TYPES_H_
+
+#include <stdbool.h>
+#include <stddef.h>
+
+#define __SANE_USERSPACE_TYPES__        /* For PPC64, to get LL64 types */
+#include <asm/types.h>
+
+struct page;
+struct kmem_cache;
+
+typedef unsigned gfp_t;
+
+typedef __u64 u64;
+typedef __s64 s64;
+
+typedef __u32 u32;
+typedef __s32 s32;
+
+typedef __u16 u16;
+typedef __s16 s16;
+
+typedef __u8  u8;
+typedef __s8  s8;
+
+#ifdef __CHECKER__
+#define __bitwise__ __attribute__((bitwise))
+#else
+#define __bitwise__
+#endif
+#ifdef __CHECK_ENDIAN__
+#define __bitwise __bitwise__
+#else
+#define __bitwise
+#endif
+
+
+typedef __u16 __bitwise __le16;
+typedef __u16 __bitwise __be16;
+typedef __u32 __bitwise __le32;
+typedef __u32 __bitwise __be32;
+typedef __u64 __bitwise __le64;
+typedef __u64 __bitwise __be64;
+
+struct list_head {
+        struct list_head *next, *prev;
+};
+
+struct hlist_head {
+        struct hlist_node *first;
+};
+
+struct hlist_node {
+        struct hlist_node *next, **pprev;
+};
+
+#endif
diff --git a/tools/lib/lockdep/uinclude/trace/events/lock.h b/tools/lib/lockdep/uinclude/trace/events/lock.h
new file mode 100644
index 000000000000..fab00ff936d1
--- /dev/null
+++ b/tools/lib/lockdep/uinclude/trace/events/lock.h
@@ -0,0 +1,3 @@
+
+/* empty file */
+