Merge branch 'linus' into core/locking

diff --git a/Documentation/lockstat.txt b/Documentation/lockstat.txt
index 4ba4664..9cb9138 100644 (file)
--- a/Documentation/lockstat.txt
+++ b/Documentation/lockstat.txt
@@ -71,35 +71,50 @@ Look at the current lock statistics:
 
 # less /proc/lock_stat
 
-01 lock_stat version 0.2
+01 lock_stat version 0.3
 02 -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 03                               class name    con-bounces    contentions   waittime-min   waittime-max waittime-total    acq-bounces   acquisitions   holdtime-min   holdtime-max holdtime-total
 04 -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 05
-06               &inode->i_data.tree_lock-W:            15          21657           0.18     1093295.30 11547131054.85             58          10415           0.16          87.51        6387.60
-07               &inode->i_data.tree_lock-R:             0              0           0.00           0.00           0.00          23302         231198           0.25           8.45       98023.38
-08               --------------------------
-09                 &inode->i_data.tree_lock              0          [<ffffffff8027c08f>] add_to_page_cache+0x5f/0x190
-10
-11 ...............................................................................................................................................................................................
-12
-13                              dcache_lock:          1037           1161           0.38          45.32         774.51           6611         243371           0.15         306.48       77387.24
-14                              -----------
-15                              dcache_lock            180          [<ffffffff802c0d7e>] sys_getcwd+0x11e/0x230
-16                              dcache_lock            165          [<ffffffff802c002a>] d_alloc+0x15a/0x210
-17                              dcache_lock             33          [<ffffffff8035818d>] _atomic_dec_and_lock+0x4d/0x70
-18                              dcache_lock              1          [<ffffffff802beef8>] shrink_dcache_parent+0x18/0x130
+06                          &mm->mmap_sem-W:           233            538 18446744073708       22924.27      607243.51           1342          45806           1.71        8595.89     1180582.34
+07                          &mm->mmap_sem-R:           205            587 18446744073708       28403.36      731975.00           1940         412426           0.58      187825.45     6307502.88
+08                          ---------------
+09                            &mm->mmap_sem            487          [<ffffffff8053491f>] do_page_fault+0x466/0x928
+10                            &mm->mmap_sem            179          [<ffffffff802a6200>] sys_mprotect+0xcd/0x21d
+11                            &mm->mmap_sem            279          [<ffffffff80210a57>] sys_mmap+0x75/0xce
+12                            &mm->mmap_sem             76          [<ffffffff802a490b>] sys_munmap+0x32/0x59
+13                          ---------------
+14                            &mm->mmap_sem            270          [<ffffffff80210a57>] sys_mmap+0x75/0xce
+15                            &mm->mmap_sem            431          [<ffffffff8053491f>] do_page_fault+0x466/0x928
+16                            &mm->mmap_sem            138          [<ffffffff802a490b>] sys_munmap+0x32/0x59
+17                            &mm->mmap_sem            145          [<ffffffff802a6200>] sys_mprotect+0xcd/0x21d
+18
+19 ...............................................................................................................................................................................................
+20
+21                              dcache_lock:           621            623           0.52         118.26        1053.02           6745          91930           0.29         316.29      118423.41
+22                              -----------
+23                              dcache_lock            179          [<ffffffff80378274>] _atomic_dec_and_lock+0x34/0x54
+24                              dcache_lock            113          [<ffffffff802cc17b>] d_alloc+0x19a/0x1eb
+25                              dcache_lock             99          [<ffffffff802ca0dc>] d_rehash+0x1b/0x44
+26                              dcache_lock            104          [<ffffffff802cbca0>] d_instantiate+0x36/0x8a
+27                              -----------
+28                              dcache_lock            192          [<ffffffff80378274>] _atomic_dec_and_lock+0x34/0x54
+29                              dcache_lock             98          [<ffffffff802ca0dc>] d_rehash+0x1b/0x44
+30                              dcache_lock             72          [<ffffffff802cc17b>] d_alloc+0x19a/0x1eb
+31                              dcache_lock            112          [<ffffffff802cbca0>] d_instantiate+0x36/0x8a
 
 This excerpt shows the first two lock class statistics. Line 01 shows the
 output version - each time the format changes this will be updated. Line 02-04
-show the header with column descriptions. Lines 05-10 and 13-18 show the actual
+show the header with column descriptions. Lines 05-18 and 20-31 show the actual
 statistics. These statistics come in two parts; the actual stats separated by a
-short separator (line 08, 14) from the contention points.
+short separator (line 08, 13) from the contention points.
 
-The first lock (05-10) is a read/write lock, and shows two lines above the
+The first lock (05-18) is a read/write lock, and shows two lines above the
 short separator. The contention points don't match the column descriptors,
-they have two: contentions and [<IP>] symbol.
+they have two: contentions and [<IP>] symbol. The second set of contention
+points are the points we're contending with.
 
+The integer part of the time values is in us.
 
 View the top contending locks:
 

diff --git a/arch/um/include/asm/system.h b/arch/um/include/asm/system.h
index 753346e..ae5f94d 100644 (file)
--- a/arch/um/include/asm/system.h
+++ b/arch/um/include/asm/system.h
@@ -11,21 +11,21 @@ extern int get_signals(void);
 extern void block_signals(void);
 extern void unblock_signals(void);
 
-#define local_save_flags(flags) do { typecheck(unsigned long, flags); \
+#define raw_local_save_flags(flags) do { typecheck(unsigned long, flags); \
                                     (flags) = get_signals(); } while(0)
-#define local_irq_restore(flags) do { typecheck(unsigned long, flags); \
+#define raw_local_irq_restore(flags) do { typecheck(unsigned long, flags); \
                                      set_signals(flags); } while(0)
 
-#define local_irq_save(flags) do { local_save_flags(flags); \
-                                   local_irq_disable(); } while(0)
+#define raw_local_irq_save(flags) do { raw_local_save_flags(flags); \
+                                   raw_local_irq_disable(); } while(0)
 
-#define local_irq_enable() unblock_signals()
-#define local_irq_disable() block_signals()
+#define raw_local_irq_enable() unblock_signals()
+#define raw_local_irq_disable() block_signals()
 
 #define irqs_disabled()                 \
 ({                                      \
         unsigned long flags;            \
-        local_save_flags(flags);        \
+        raw_local_save_flags(flags);        \
         (flags == 0);                   \
 })
 

diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h
index 35c5492..99192bb 100644 (file)
--- a/arch/x86/include/asm/uaccess.h
+++ b/arch/x86/include/asm/uaccess.h
@@ -157,6 +157,7 @@ extern int __get_user_bad(void);
        int __ret_gu;                                                   \
        unsigned long __val_gu;                                         \
        __chk_user_ptr(ptr);                                            \
+       might_fault();                                                  \
        switch (sizeof(*(ptr))) {                                       \
        case 1:                                                         \
                __get_user_x(1, __ret_gu, __val_gu, ptr);               \
@@ -241,6 +242,7 @@ extern void __put_user_8(void);
        int __ret_pu;                                           \
        __typeof__(*(ptr)) __pu_val;                            \
        __chk_user_ptr(ptr);                                    \
+       might_fault();                                          \
        __pu_val = x;                                           \
        switch (sizeof(*(ptr))) {                               \
        case 1:                                                 \

diff --git a/arch/x86/include/asm/uaccess_32.h b/arch/x86/include/asm/uaccess_32.h
index d095a3a..5e06259 100644 (file)
--- a/arch/x86/include/asm/uaccess_32.h
+++ b/arch/x86/include/asm/uaccess_32.h
@@ -82,8 +82,8 @@ __copy_to_user_inatomic(void __user *to, const void *from, unsigned long n)
 static __always_inline unsigned long __must_check
 __copy_to_user(void __user *to, const void *from, unsigned long n)
 {
-       might_sleep();
-       return __copy_to_user_inatomic(to, from, n);
+       might_fault();
+       return __copy_to_user_inatomic(to, from, n);
 }
 
 static __always_inline unsigned long
@@ -137,7 +137,7 @@ __copy_from_user_inatomic(void *to, const void __user *from, unsigned long n)
 static __always_inline unsigned long
 __copy_from_user(void *to, const void __user *from, unsigned long n)
 {
-       might_sleep();
+       might_fault();
        if (__builtin_constant_p(n)) {
                unsigned long ret;
 
@@ -159,7 +159,7 @@ __copy_from_user(void *to, const void __user *from, unsigned long n)
 static __always_inline unsigned long __copy_from_user_nocache(void *to,
                                const void __user *from, unsigned long n)
 {
-       might_sleep();
+       might_fault();
        if (__builtin_constant_p(n)) {
                unsigned long ret;
 

diff --git a/arch/x86/include/asm/uaccess_64.h b/arch/x86/include/asm/uaccess_64.h
index 664f152..543ba88 100644 (file)
--- a/arch/x86/include/asm/uaccess_64.h
+++ b/arch/x86/include/asm/uaccess_64.h
@@ -29,6 +29,8 @@ static __always_inline __must_check
 int __copy_from_user(void *dst, const void __user *src, unsigned size)
 {
        int ret = 0;
+
+       might_fault();
        if (!__builtin_constant_p(size))
                return copy_user_generic(dst, (__force void *)src, size);
        switch (size) {
@@ -71,6 +73,8 @@ static __always_inline __must_check
 int __copy_to_user(void __user *dst, const void *src, unsigned size)
 {
        int ret = 0;
+
+       might_fault();
        if (!__builtin_constant_p(size))
                return copy_user_generic((__force void *)dst, src, size);
        switch (size) {
@@ -113,6 +117,8 @@ static __always_inline __must_check
 int __copy_in_user(void __user *dst, const void __user *src, unsigned size)
 {
        int ret = 0;
+
+       might_fault();
        if (!__builtin_constant_p(size))
                return copy_user_generic((__force void *)dst,
                                         (__force void *)src, size);

diff --git a/arch/x86/lib/usercopy_32.c b/arch/x86/lib/usercopy_32.c
index 9e68075..4a20b2f 100644 (file)
--- a/arch/x86/lib/usercopy_32.c
+++ b/arch/x86/lib/usercopy_32.c
@@ -39,7 +39,7 @@ static inline int __movsl_is_ok(unsigned long a1, unsigned long a2, unsigned lon
 #define __do_strncpy_from_user(dst, src, count, res)                      \
 do {                                                                      \
        int __d0, __d1, __d2;                                              \
-       might_sleep();                                                     \
+       might_fault();                                                     \
        __asm__ __volatile__(                                              \
                "       testl %1,%1\n"                                     \
                "       jz 2f\n"                                           \
@@ -126,7 +126,7 @@ EXPORT_SYMBOL(strncpy_from_user);
 #define __do_clear_user(addr,size)                                     \
 do {                                                                   \
        int __d0;                                                       \
-       might_sleep();                                                  \
+       might_fault();                                                  \
        __asm__ __volatile__(                                           \
                "0:     rep; stosl\n"                                   \
                "       movl %2,%0\n"                                   \
@@ -155,7 +155,7 @@ do {                                                                        \
 unsigned long
 clear_user(void __user *to, unsigned long n)
 {
-       might_sleep();
+       might_fault();
        if (access_ok(VERIFY_WRITE, to, n))
                __do_clear_user(to, n);
        return n;
@@ -197,7 +197,7 @@ long strnlen_user(const char __user *s, long n)
        unsigned long mask = -__addr_ok(s);
        unsigned long res, tmp;
 
-       might_sleep();
+       might_fault();
 
        __asm__ __volatile__(
                "       testl %0, %0\n"

diff --git a/arch/x86/lib/usercopy_64.c b/arch/x86/lib/usercopy_64.c
index f4df6e7..64d6c84 100644 (file)
--- a/arch/x86/lib/usercopy_64.c
+++ b/arch/x86/lib/usercopy_64.c
@@ -15,7 +15,7 @@
 #define __do_strncpy_from_user(dst,src,count,res)                         \
 do {                                                                      \
        long __d0, __d1, __d2;                                             \
-       might_sleep();                                                     \
+       might_fault();                                                     \
        __asm__ __volatile__(                                              \
                "       testq %1,%1\n"                                     \
                "       jz 2f\n"                                           \
@@ -64,7 +64,7 @@ EXPORT_SYMBOL(strncpy_from_user);
 unsigned long __clear_user(void __user *addr, unsigned long size)
 {
        long __d0;
-       might_sleep();
+       might_fault();
        /* no memory constraint because it doesn't change any memory gcc knows
           about */
        asm volatile(

diff --git a/include/linux/debug_locks.h b/include/linux/debug_locks.h
index 4aaa4af..096476f 100644 (file)
--- a/include/linux/debug_locks.h
+++ b/include/linux/debug_locks.h
@@ -17,7 +17,7 @@ extern int debug_locks_off(void);
 ({                                                                     \
        int __ret = 0;                                                  \
                                                                        \
-       if (unlikely(c)) {                                              \
+       if (!oops_in_progress && unlikely(c)) {                         \
                if (debug_locks_off() && !debug_locks_silent)           \
                        WARN_ON(1);                                     \
                __ret = 1;                                              \

diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index fba141d..69a9bfd 100644 (file)
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -141,6 +141,15 @@ extern int _cond_resched(void);
                (__x < 0) ? -__x : __x;         \
        })
 
+#ifdef CONFIG_PROVE_LOCKING
+void might_fault(void);
+#else
+static inline void might_fault(void)
+{
+       might_sleep();
+}
+#endif
+
 extern struct atomic_notifier_head panic_notifier_list;
 extern long (*panic_blink)(long time);
 NORET_TYPE void panic(const char * fmt, ...)

diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
index 331e5f1..fc9f8e8 100644 (file)
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h
@@ -73,6 +73,8 @@ struct lock_class_key {
        struct lockdep_subclass_key     subkeys[MAX_LOCKDEP_SUBCLASSES];
 };
 
+#define LOCKSTAT_POINTS                4
+
 /*
  * The lock-class itself:
  */
@@ -119,7 +121,8 @@ struct lock_class {
        int                             name_version;
 
 #ifdef CONFIG_LOCK_STAT
-       unsigned long                   contention_point[4];
+       unsigned long                   contention_point[LOCKSTAT_POINTS];
+       unsigned long                   contending_point[LOCKSTAT_POINTS];
 #endif
 };
 
@@ -144,6 +147,7 @@ enum bounce_type {
 
 struct lock_class_stats {
        unsigned long                   contention_point[4];
+       unsigned long                   contending_point[4];
        struct lock_time                read_waittime;
        struct lock_time                write_waittime;
        struct lock_time                read_holdtime;
@@ -165,6 +169,7 @@ struct lockdep_map {
        const char                      *name;
 #ifdef CONFIG_LOCK_STAT
        int                             cpu;
+       unsigned long                   ip;
 #endif
 };
 
@@ -355,7 +360,7 @@ struct lock_class_key { };
 #ifdef CONFIG_LOCK_STAT
 
 extern void lock_contended(struct lockdep_map *lock, unsigned long ip);
-extern void lock_acquired(struct lockdep_map *lock);
+extern void lock_acquired(struct lockdep_map *lock, unsigned long ip);
 
 #define LOCK_CONTENDED(_lock, try, lock)                       \
 do {                                                           \
@@ -363,13 +368,13 @@ do {                                                              \
                lock_contended(&(_lock)->dep_map, _RET_IP_);    \
                lock(_lock);                                    \
        }                                                       \
-       lock_acquired(&(_lock)->dep_map);                       \
+       lock_acquired(&(_lock)->dep_map, _RET_IP_);                     \
 } while (0)
 
 #else /* CONFIG_LOCK_STAT */
 
 #define lock_contended(lockdep_map, ip) do {} while (0)
-#define lock_acquired(lockdep_map) do {} while (0)
+#define lock_acquired(lockdep_map, ip) do {} while (0)
 
 #define LOCK_CONTENDED(_lock, try, lock) \
        lock(_lock)
@@ -480,4 +485,22 @@ static inline void print_irqtrace_events(struct task_struct *curr)
 # define lock_map_release(l)                   do { } while (0)
 #endif
 
+#ifdef CONFIG_PROVE_LOCKING
+# define might_lock(lock)                                              \
+do {                                                                   \
+       typecheck(struct lockdep_map *, &(lock)->dep_map);              \
+       lock_acquire(&(lock)->dep_map, 0, 0, 0, 2, NULL, _THIS_IP_);    \
+       lock_release(&(lock)->dep_map, 0, _THIS_IP_);                   \
+} while (0)
+# define might_lock_read(lock)                                                 \
+do {                                                                   \
+       typecheck(struct lockdep_map *, &(lock)->dep_map);              \
+       lock_acquire(&(lock)->dep_map, 0, 0, 1, 2, NULL, _THIS_IP_);    \
+       lock_release(&(lock)->dep_map, 0, _THIS_IP_);                   \
+} while (0)
+#else
+# define might_lock(lock) do { } while (0)
+# define might_lock_read(lock) do { } while (0)
+#endif
+
 #endif /* __LINUX_LOCKDEP_H */

diff --git a/include/linux/mutex.h b/include/linux/mutex.h
index bc6da10..7a0e5c4 100644 (file)
--- a/include/linux/mutex.h
+++ b/include/linux/mutex.h
@@ -144,6 +144,8 @@ extern int __must_check mutex_lock_killable(struct mutex *lock);
 /*
  * NOTE: mutex_trylock() follows the spin_trylock() convention,
  *       not the down_trylock() convention!
+ *
+ * Returns 1 if the mutex has been acquired successfully, and 0 on contention.
  */
 extern int mutex_trylock(struct mutex *lock);
 extern void mutex_unlock(struct mutex *lock);

diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h
index fec6dec..6b58367 100644 (file)
--- a/include/linux/uaccess.h
+++ b/include/linux/uaccess.h
@@ -78,7 +78,7 @@ static inline unsigned long __copy_from_user_nocache(void *to,
                                                        \
                set_fs(KERNEL_DS);                      \
                pagefault_disable();                    \
-               ret = __get_user(retval, (__force typeof(retval) __user *)(addr));              \
+               ret = __copy_from_user_inatomic(&(retval), (__force typeof(retval) __user *)(addr), sizeof(retval));            \
                pagefault_enable();                     \
                set_fs(old_fs);                         \
                ret;                                    \

diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index 06e1571..a428583 100644 (file)
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -136,16 +136,16 @@ static inline struct lock_class *hlock_class(struct held_lock *hlock)
 #ifdef CONFIG_LOCK_STAT
 static DEFINE_PER_CPU(struct lock_class_stats[MAX_LOCKDEP_KEYS], lock_stats);
 
-static int lock_contention_point(struct lock_class *class, unsigned long ip)
+static int lock_point(unsigned long points[], unsigned long ip)
 {
        int i;
 
-       for (i = 0; i < ARRAY_SIZE(class->contention_point); i++) {
-               if (class->contention_point[i] == 0) {
-                       class->contention_point[i] = ip;
+       for (i = 0; i < LOCKSTAT_POINTS; i++) {
+               if (points[i] == 0) {
+                       points[i] = ip;
                        break;
                }
-               if (class->contention_point[i] == ip)
+               if (points[i] == ip)
                        break;
        }
 
@@ -185,6 +185,9 @@ struct lock_class_stats lock_stats(struct lock_class *class)
                for (i = 0; i < ARRAY_SIZE(stats.contention_point); i++)
                        stats.contention_point[i] += pcs->contention_point[i];
 
+               for (i = 0; i < ARRAY_SIZE(stats.contending_point); i++)
+                       stats.contending_point[i] += pcs->contending_point[i];
+
                lock_time_add(&pcs->read_waittime, &stats.read_waittime);
                lock_time_add(&pcs->write_waittime, &stats.write_waittime);
 
@@ -209,6 +212,7 @@ void clear_lock_stats(struct lock_class *class)
                memset(cpu_stats, 0, sizeof(struct lock_class_stats));
        }
        memset(class->contention_point, 0, sizeof(class->contention_point));
+       memset(class->contending_point, 0, sizeof(class->contending_point));
 }
 
 static struct lock_class_stats *get_lock_stats(struct lock_class *class)
@@ -2999,7 +3003,7 @@ __lock_contended(struct lockdep_map *lock, unsigned long ip)
        struct held_lock *hlock, *prev_hlock;
        struct lock_class_stats *stats;
        unsigned int depth;
-       int i, point;
+       int i, contention_point, contending_point;
 
        depth = curr->lockdep_depth;
        if (DEBUG_LOCKS_WARN_ON(!depth))
@@ -3023,18 +3027,22 @@ __lock_contended(struct lockdep_map *lock, unsigned long ip)
 found_it:
        hlock->waittime_stamp = sched_clock();
 
-       point = lock_contention_point(hlock_class(hlock), ip);
+       contention_point = lock_point(hlock_class(hlock)->contention_point, ip);
+       contending_point = lock_point(hlock_class(hlock)->contending_point,
+                                     lock->ip);
 
        stats = get_lock_stats(hlock_class(hlock));
-       if (point < ARRAY_SIZE(stats->contention_point))
-               stats->contention_point[point]++;
+       if (contention_point < LOCKSTAT_POINTS)
+               stats->contention_point[contention_point]++;
+       if (contending_point < LOCKSTAT_POINTS)
+               stats->contending_point[contending_point]++;
        if (lock->cpu != smp_processor_id())
                stats->bounces[bounce_contended + !!hlock->read]++;
        put_lock_stats(stats);
 }
 
 static void
-__lock_acquired(struct lockdep_map *lock)
+__lock_acquired(struct lockdep_map *lock, unsigned long ip)
 {
        struct task_struct *curr = current;
        struct held_lock *hlock, *prev_hlock;
@@ -3083,6 +3091,7 @@ found_it:
        put_lock_stats(stats);
 
        lock->cpu = cpu;
+       lock->ip = ip;
 }
 
 void lock_contended(struct lockdep_map *lock, unsigned long ip)
@@ -3104,7 +3113,7 @@ void lock_contended(struct lockdep_map *lock, unsigned long ip)
 }
 EXPORT_SYMBOL_GPL(lock_contended);
 
-void lock_acquired(struct lockdep_map *lock)
+void lock_acquired(struct lockdep_map *lock, unsigned long ip)
 {
        unsigned long flags;
 
@@ -3117,7 +3126,7 @@ void lock_acquired(struct lockdep_map *lock)
        raw_local_irq_save(flags);
        check_flags(flags);
        current->lockdep_recursion = 1;
-       __lock_acquired(lock);
+       __lock_acquired(lock, ip);
        current->lockdep_recursion = 0;
        raw_local_irq_restore(flags);
 }

diff --git a/kernel/lockdep_proc.c b/kernel/lockdep_proc.c
index 20dbcbf..13716b8 100644 (file)
--- a/kernel/lockdep_proc.c
+++ b/kernel/lockdep_proc.c
@@ -470,11 +470,12 @@ static void seq_line(struct seq_file *m, char c, int offset, int length)
 
 static void snprint_time(char *buf, size_t bufsiz, s64 nr)
 {
-       unsigned long rem;
+       s64 div;
+       s32 rem;
 
        nr += 5; /* for display rounding */
-       rem = do_div(nr, 1000); /* XXX: do_div_signed */
-       snprintf(buf, bufsiz, "%lld.%02d", (long long)nr, (int)rem/10);
+       div = div_s64_rem(nr, 1000, &rem);
+       snprintf(buf, bufsiz, "%lld.%02d", (long long)div, (int)rem/10);
 }
 
 static void seq_time(struct seq_file *m, s64 time)
@@ -556,7 +557,7 @@ static void seq_stats(struct seq_file *m, struct lock_stat_data *data)
        if (stats->read_holdtime.nr)
                namelen += 2;
 
-       for (i = 0; i < ARRAY_SIZE(class->contention_point); i++) {
+       for (i = 0; i < LOCKSTAT_POINTS; i++) {
                char sym[KSYM_SYMBOL_LEN];
                char ip[32];
 
@@ -573,6 +574,23 @@ static void seq_stats(struct seq_file *m, struct lock_stat_data *data)
                                stats->contention_point[i],
                                ip, sym);
        }
+       for (i = 0; i < LOCKSTAT_POINTS; i++) {
+               char sym[KSYM_SYMBOL_LEN];
+               char ip[32];
+
+               if (class->contending_point[i] == 0)
+                       break;
+
+               if (!i)
+                       seq_line(m, '-', 40-namelen, namelen);
+
+               sprint_symbol(sym, class->contending_point[i]);
+               snprintf(ip, sizeof(ip), "[<%p>]",
+                               (void *)class->contending_point[i]);
+               seq_printf(m, "%40s %14lu %29s %s\n", name,
+                               stats->contending_point[i],
+                               ip, sym);
+       }
        if (i) {
                seq_puts(m, "\n");
                seq_line(m, '.', 0, 40 + 1 + 10 * (14 + 1));
@@ -582,7 +600,7 @@ static void seq_stats(struct seq_file *m, struct lock_stat_data *data)
 
 static void seq_header(struct seq_file *m)
 {
-       seq_printf(m, "lock_stat version 0.2\n");
+       seq_printf(m, "lock_stat version 0.3\n");
        seq_line(m, '-', 0, 40 + 1 + 10 * (14 + 1));
        seq_printf(m, "%40s %14s %14s %14s %14s %14s %14s %14s %14s "
                        "%14s %14s\n",

diff --git a/kernel/mutex.c b/kernel/mutex.c
index 12c779d..39a3816 100644 (file)
--- a/kernel/mutex.c
+++ b/kernel/mutex.c
@@ -184,7 +184,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
        }
 
 done:
-       lock_acquired(&lock->dep_map);
+       lock_acquired(&lock->dep_map, ip);
        /* got the lock - rejoice! */
        mutex_remove_waiter(lock, &waiter, task_thread_info(task));
        debug_mutex_set_owner(lock, task_thread_info(task));

diff --git a/kernel/sched.c b/kernel/sched.c
index 50a21f9..2a106b6 100644 (file)
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -4336,7 +4336,7 @@ void __kprobes sub_preempt_count(int val)
        /*
         * Underflow?
         */
-       if (DEBUG_LOCKS_WARN_ON(val > preempt_count()))
+       if (DEBUG_LOCKS_WARN_ON(val > preempt_count() - (!!kernel_locked())))
                return;
        /*
         * Is the spinlock portion underflowing?

diff --git a/mm/memory.c b/mm/memory.c
index 164951c..fc031d6 100644 (file)
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -3049,3 +3049,18 @@ void print_vma_addr(char *prefix, unsigned long ip)
        }
        up_read(&current->mm->mmap_sem);
 }
+
+#ifdef CONFIG_PROVE_LOCKING
+void might_fault(void)
+{
+       might_sleep();
+       /*
+        * it would be nicer only to annotate paths which are not under
+        * pagefault_disable, however that requires a larger audit and
+        * providing helpers like get_user_atomic.
+        */
+       if (!in_atomic() && current->mm)
+               might_lock_read(&current->mm->mmap_sem);
+}
+EXPORT_SYMBOL(might_fault);
+#endif