17 files changed, 221 insertions, 237 deletions

diff --git a/Documentation/lockstat.txt b/Documentation/lockstat.txt
index cef00d42ed5b..dd2f7b26ca30 100644
--- a/Documentation/lockstat.txt
+++ b/Documentation/lockstat.txt
@@ -65,7 +65,7 @@ that had to wait on lock acquisition.
 
  - CONFIGURATION
 
-Lock statistics are enabled via CONFIG_LOCK_STATS.
+Lock statistics are enabled via CONFIG_LOCK_STAT.
 
  - USAGE
 
diff --git a/drivers/char/random.c b/drivers/char/random.c
index 85e81ec1451e..594bda9dcfc8 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -445,7 +445,7 @@ static struct entropy_store input_pool = {
 	.poolinfo = &poolinfo_table[0],
 	.name = "input",
 	.limit = 1,
-	.lock = __SPIN_LOCK_UNLOCKED(&input_pool.lock),
+	.lock = __SPIN_LOCK_UNLOCKED(input_pool.lock),
 	.pool = input_pool_data
 };
 
@@ -454,7 +454,7 @@ static struct entropy_store blocking_pool = {
 	.name = "blocking",
 	.limit = 1,
 	.pull = &input_pool,
-	.lock = __SPIN_LOCK_UNLOCKED(&blocking_pool.lock),
+	.lock = __SPIN_LOCK_UNLOCKED(blocking_pool.lock),
 	.pool = blocking_pool_data
 };
 
@@ -462,7 +462,7 @@ static struct entropy_store nonblocking_pool = {
 	.poolinfo = &poolinfo_table[1],
 	.name = "nonblocking",
 	.pull = &input_pool,
-	.lock = __SPIN_LOCK_UNLOCKED(&nonblocking_pool.lock),
+	.lock = __SPIN_LOCK_UNLOCKED(nonblocking_pool.lock),
 	.pool = nonblocking_pool_data
 };
 
diff --git a/drivers/idle/i7300_idle.c b/drivers/idle/i7300_idle.c
index fa080ebd568f..ffeebc7e9f1c 100644
--- a/drivers/idle/i7300_idle.c
+++ b/drivers/idle/i7300_idle.c
@@ -75,7 +75,7 @@ static unsigned long past_skip;
 
 static struct pci_dev *fbd_dev;
 
-static spinlock_t i7300_idle_lock;
+static raw_spinlock_t i7300_idle_lock;
 static int i7300_idle_active;
 
 static u8 i7300_idle_thrtctl_saved;
@@ -457,7 +457,7 @@ static int i7300_idle_notifier(struct notifier_block *nb, unsigned long val,
 		idle_begin_time = ktime_get();
 	}
 
-	spin_lock_irqsave(&i7300_idle_lock, flags);
+	raw_spin_lock_irqsave(&i7300_idle_lock, flags);
 	if (val == IDLE_START) {
 
 		cpumask_set_cpu(smp_processor_id(), idle_cpumask);
@@ -506,7 +506,7 @@ static int i7300_idle_notifier(struct notifier_block *nb, unsigned long val,
 		}
 	}
 end:
-	spin_unlock_irqrestore(&i7300_idle_lock, flags);
+	raw_spin_unlock_irqrestore(&i7300_idle_lock, flags);
 	return 0;
 }
 
@@ -548,7 +548,7 @@ struct debugfs_file_info {
 
 static int __init i7300_idle_init(void)
 {
-	spin_lock_init(&i7300_idle_lock);
+	raw_spin_lock_init(&i7300_idle_lock);
 	total_us = 0;
 
 	if (i7300_idle_platform_probe(&fbd_dev, &ioat_dev, forceload))
diff --git a/drivers/usb/chipidea/debug.c b/drivers/usb/chipidea/debug.c
index 3bc244d2636a..a62c4a47d52c 100644
--- a/drivers/usb/chipidea/debug.c
+++ b/drivers/usb/chipidea/debug.c
@@ -222,7 +222,7 @@ static struct {
 } dbg_data = {
 	.idx = 0,
 	.tty = 0,
-	.lck = __RW_LOCK_UNLOCKED(lck)
+	.lck = __RW_LOCK_UNLOCKED(dbg_data.lck)
 };
 
 /**
diff --git a/fs/file.c b/fs/file.c
index 2b3570b7caeb..3906d9577a18 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -516,7 +516,7 @@ struct files_struct init_files = {
 		.close_on_exec	= init_files.close_on_exec_init,
 		.open_fds	= init_files.open_fds_init,
 	},
-	.file_lock	= __SPIN_LOCK_UNLOCKED(init_task.file_lock),
+	.file_lock	= __SPIN_LOCK_UNLOCKED(init_files.file_lock),
 };
 
 /*
diff --git a/include/asm-generic/cmpxchg-local.h b/include/asm-generic/cmpxchg-local.h
index 2533fddd34a6..d8d4c898c1bb 100644
--- a/include/asm-generic/cmpxchg-local.h
+++ b/include/asm-generic/cmpxchg-local.h
@@ -21,7 +21,7 @@ static inline unsigned long __cmpxchg_local_generic(volatile void *ptr,
 	if (size == 8 && sizeof(unsigned long) != 8)
 		wrong_size_cmpxchg(ptr);
 
-	local_irq_save(flags);
+	raw_local_irq_save(flags);
 	switch (size) {
 	case 1: prev = *(u8 *)ptr;
 		if (prev == old)
@@ -42,7 +42,7 @@ static inline unsigned long __cmpxchg_local_generic(volatile void *ptr,
 	default:
 		wrong_size_cmpxchg(ptr);
 	}
-	local_irq_restore(flags);
+	raw_local_irq_restore(flags);
 	return prev;
 }
 
@@ -55,11 +55,11 @@ static inline u64 __cmpxchg64_local_generic(volatile void *ptr,
 	u64 prev;
 	unsigned long flags;
 
-	local_irq_save(flags);
+	raw_local_irq_save(flags);
 	prev = *(u64 *)ptr;
 	if (prev == old)
 		*(u64 *)ptr = new;
-	local_irq_restore(flags);
+	raw_local_irq_restore(flags);
 	return prev;
 }
 
diff --git a/include/linux/idr.h b/include/linux/idr.h
index de7e190f1af4..e5eb125effe6 100644
--- a/include/linux/idr.h
+++ b/include/linux/idr.h
@@ -136,7 +136,7 @@ struct ida {
 	struct ida_bitmap	*free_bitmap;
 };
 
-#define IDA_INIT(name)		{ .idr = IDR_INIT(name), .free_bitmap = NULL, }
+#define IDA_INIT(name)		{ .idr = IDR_INIT((name).idr), .free_bitmap = NULL, }
 #define DEFINE_IDA(name)	struct ida name = IDA_INIT(name)
 
 int ida_pre_get(struct ida *ida, gfp_t gfp_mask);
diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
index bfe88c4aa251..f1e877b79ed8 100644
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h
@@ -412,7 +412,7 @@ struct lock_class_key { };
 
 #define lockdep_depth(tsk)	(0)
 
-#define lockdep_assert_held(l)			do { } while (0)
+#define lockdep_assert_held(l)			do { (void)(l); } while (0)
 
 #define lockdep_recursing(tsk)			(0)
 
diff --git a/include/linux/seqlock.h b/include/linux/seqlock.h
index 600060e25ec6..18299057402f 100644
--- a/include/linux/seqlock.h
+++ b/include/linux/seqlock.h
@@ -30,92 +30,12 @@
 #include <linux/preempt.h>
 #include <asm/processor.h>
 
-typedef struct {
-	unsigned sequence;
-	spinlock_t lock;
-} seqlock_t;
-
-/*
- * These macros triggered gcc-3.x compile-time problems.  We think these are
- * OK now.  Be cautious.
- */
-#define __SEQLOCK_UNLOCKED(lockname) \
-		 { 0, __SPIN_LOCK_UNLOCKED(lockname) }
-
-#define seqlock_init(x)					\
-	do {						\
-		(x)->sequence = 0;			\
-		spin_lock_init(&(x)->lock);		\
-	} while (0)
-
-#define DEFINE_SEQLOCK(x) \
-		seqlock_t x = __SEQLOCK_UNLOCKED(x)
-
-/* Lock out other writers and update the count.
- * Acts like a normal spin_lock/unlock.
- * Don't need preempt_disable() because that is in the spin_lock already.
- */
-static inline void write_seqlock(seqlock_t *sl)
-{
-	spin_lock(&sl->lock);
-	++sl->sequence;
-	smp_wmb();
-}
-
-static inline void write_sequnlock(seqlock_t *sl)
-{
-	smp_wmb();
-	sl->sequence++;
-	spin_unlock(&sl->lock);
-}
-
-static inline int write_tryseqlock(seqlock_t *sl)
-{
-	int ret = spin_trylock(&sl->lock);
-
-	if (ret) {
-		++sl->sequence;
-		smp_wmb();
-	}
-	return ret;
-}
-
-/* Start of read calculation -- fetch last complete writer token */
-static __always_inline unsigned read_seqbegin(const seqlock_t *sl)
-{
-	unsigned ret;
-
-repeat:
-	ret = ACCESS_ONCE(sl->sequence);
-	if (unlikely(ret & 1)) {
-		cpu_relax();
-		goto repeat;
-	}
-	smp_rmb();
-
-	return ret;
-}
-
-/*
- * Test if reader processed invalid data.
- *
- * If sequence value changed then writer changed data while in section.
- */
-static __always_inline int read_seqretry(const seqlock_t *sl, unsigned start)
-{
-	smp_rmb();
-
-	return unlikely(sl->sequence != start);
-}
-
-
 /*
  * Version using sequence counter only.
  * This can be used when code has its own mutex protecting the
  * updating starting before the write_seqcountbeqin() and ending
  * after the write_seqcount_end().
  */
-
 typedef struct seqcount {
 	unsigned sequence;
 } seqcount_t;
@@ -218,7 +138,6 @@ static inline int __read_seqcount_retry(const seqcount_t *s, unsigned start)
 static inline int read_seqcount_retry(const seqcount_t *s, unsigned start)
 {
 	smp_rmb();
-
 	return __read_seqcount_retry(s, start);
 }
 
@@ -252,31 +171,101 @@ static inline void write_seqcount_barrier(seqcount_t *s)
 	s->sequence+=2;
 }
 
+typedef struct {
+	struct seqcount seqcount;
+	spinlock_t lock;
+} seqlock_t;
+
 /*
- * Possible sw/hw IRQ protected versions of the interfaces.
+ * These macros triggered gcc-3.x compile-time problems.  We think these are
+ * OK now.  Be cautious.
  */
-#define write_seqlock_irqsave(lock, flags)				\
-	do { local_irq_save(flags); write_seqlock(lock); } while (0)
-#define write_seqlock_irq(lock)						\
-	do { local_irq_disable();   write_seqlock(lock); } while (0)
-#define write_seqlock_bh(lock)						\
-        do { local_bh_disable();    write_seqlock(lock); } while (0)
+#define __SEQLOCK_UNLOCKED(lockname)			\
+	{						\
+		.seqcount = SEQCNT_ZERO,		\
+		.lock =	__SPIN_LOCK_UNLOCKED(lockname)	\
+	}
+
+#define seqlock_init(x)					\
+	do {						\
+		seqcount_init(&(x)->seqcount);		\
+		spin_lock_init(&(x)->lock);		\
+	} while (0)
 
-#define write_sequnlock_irqrestore(lock, flags)				\
-	do { write_sequnlock(lock); local_irq_restore(flags); } while(0)
-#define write_sequnlock_irq(lock)					\
-	do { write_sequnlock(lock); local_irq_enable(); } while(0)
-#define write_sequnlock_bh(lock)					\
-	do { write_sequnlock(lock); local_bh_enable(); } while(0)
+#define DEFINE_SEQLOCK(x) \
+		seqlock_t x = __SEQLOCK_UNLOCKED(x)
 
-#define read_seqbegin_irqsave(lock, flags)				\
-	({ local_irq_save(flags);   read_seqbegin(lock); })
+/*
+ * Read side functions for starting and finalizing a read side section.
+ */
+static inline unsigned read_seqbegin(const seqlock_t *sl)
+{
+	return read_seqcount_begin(&sl->seqcount);
+}
 
-#define read_seqretry_irqrestore(lock, iv, flags)			\
-	({								\
-		int ret = read_seqretry(lock, iv);			\
-		local_irq_restore(flags);				\
-		ret;							\
-	})
+static inline unsigned read_seqretry(const seqlock_t *sl, unsigned start)
+{
+	return read_seqcount_retry(&sl->seqcount, start);
+}
+
+/*
+ * Lock out other writers and update the count.
+ * Acts like a normal spin_lock/unlock.
+ * Don't need preempt_disable() because that is in the spin_lock already.
+ */
+static inline void write_seqlock(seqlock_t *sl)
+{
+	spin_lock(&sl->lock);
+	write_seqcount_begin(&sl->seqcount);
+}
+
+static inline void write_sequnlock(seqlock_t *sl)
+{
+	write_seqcount_end(&sl->seqcount);
+	spin_unlock(&sl->lock);
+}
+
+static inline void write_seqlock_bh(seqlock_t *sl)
+{
+	spin_lock_bh(&sl->lock);
+	write_seqcount_begin(&sl->seqcount);
+}
+
+static inline void write_sequnlock_bh(seqlock_t *sl)
+{
+	write_seqcount_end(&sl->seqcount);
+	spin_unlock_bh(&sl->lock);
+}
+
+static inline void write_seqlock_irq(seqlock_t *sl)
+{
+	spin_lock_irq(&sl->lock);
+	write_seqcount_begin(&sl->seqcount);
+}
+
+static inline void write_sequnlock_irq(seqlock_t *sl)
+{
+	write_seqcount_end(&sl->seqcount);
+	spin_unlock_irq(&sl->lock);
+}
+
+static inline unsigned long __write_seqlock_irqsave(seqlock_t *sl)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&sl->lock, flags);
+	write_seqcount_begin(&sl->seqcount);
+	return flags;
+}
+
+#define write_seqlock_irqsave(lock, flags)				\
+	do { flags = __write_seqlock_irqsave(lock); } while (0)
+
+static inline void
+write_sequnlock_irqrestore(seqlock_t *sl, unsigned long flags)
+{
+	write_seqcount_end(&sl->seqcount);
+	spin_unlock_irqrestore(&sl->lock, flags);
+}
 
 #endif /* __LINUX_SEQLOCK_H */
diff --git a/kernel/futex.c b/kernel/futex.c
index 9618b6e9fb36..fbc07a29ec53 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -2472,8 +2472,6 @@ SYSCALL_DEFINE3(get_robust_list, int, pid,
 	if (!futex_cmpxchg_enabled)
 		return -ENOSYS;
 
-	WARN_ONCE(1, "deprecated: get_robust_list will be deleted in 2013.\n");
-
 	rcu_read_lock();
 
 	ret = -ESRCH;
diff --git a/kernel/futex_compat.c b/kernel/futex_compat.c
index 83e368b005fc..a9642d528630 100644
--- a/kernel/futex_compat.c
+++ b/kernel/futex_compat.c
@@ -142,8 +142,6 @@ compat_sys_get_robust_list(int pid, compat_uptr_t __user *head_ptr,
 	if (!futex_cmpxchg_enabled)
 		return -ENOSYS;
 
-	WARN_ONCE(1, "deprecated: get_robust_list will be deleted in 2013.\n");
-
 	rcu_read_lock();
 
 	ret = -ESRCH;
diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index 7981e5b2350d..8a0efac4f99d 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -3190,9 +3190,14 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
 #endif
 	if (unlikely(curr->lockdep_depth >= MAX_LOCK_DEPTH)) {
 		debug_locks_off();
-		printk("BUG: MAX_LOCK_DEPTH too low!\n");
+		printk("BUG: MAX_LOCK_DEPTH too low, depth: %i  max: %lu!\n",
+		       curr->lockdep_depth, MAX_LOCK_DEPTH);
 		printk("turning off the locking correctness validator.\n");
+
+		lockdep_print_held_locks(current);
+		debug_show_all_locks();
 		dump_stack();
+
 		return 0;
 	}
 
@@ -3203,7 +3208,7 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
 }
 
 static int
-print_unlock_inbalance_bug(struct task_struct *curr, struct lockdep_map *lock,
+print_unlock_imbalance_bug(struct task_struct *curr, struct lockdep_map *lock,
 			   unsigned long ip)
 {
 	if (!debug_locks_off())
@@ -3246,7 +3251,7 @@ static int check_unlock(struct task_struct *curr, struct lockdep_map *lock,
 		return 0;
 
 	if (curr->lockdep_depth <= 0)
-		return print_unlock_inbalance_bug(curr, lock, ip);
+		return print_unlock_imbalance_bug(curr, lock, ip);
 
 	return 1;
 }
@@ -3317,7 +3322,7 @@ __lock_set_class(struct lockdep_map *lock, const char *name,
 			goto found_it;
 		prev_hlock = hlock;
 	}
-	return print_unlock_inbalance_bug(curr, lock, ip);
+	return print_unlock_imbalance_bug(curr, lock, ip);
 
 found_it:
 	lockdep_init_map(lock, name, key, 0);
@@ -3384,7 +3389,7 @@ lock_release_non_nested(struct task_struct *curr,
 			goto found_it;
 		prev_hlock = hlock;
 	}
-	return print_unlock_inbalance_bug(curr, lock, ip);
+	return print_unlock_imbalance_bug(curr, lock, ip);
 
 found_it:
 	if (hlock->instance == lock)
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index b10a42bb0165..072bb066bb7d 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -23,7 +23,7 @@
  * NTP timekeeping variables:
  */
 
-DEFINE_SPINLOCK(ntp_lock);
+DEFINE_RAW_SPINLOCK(ntp_lock);
 
 
 /* USER_HZ period (usecs): */
@@ -348,7 +348,7 @@ void ntp_clear(void)
 {
 	unsigned long flags;
 
-	spin_lock_irqsave(&ntp_lock, flags);
+	raw_spin_lock_irqsave(&ntp_lock, flags);
 
 	time_adjust	= 0;		/* stop active adjtime() */
 	time_status	|= STA_UNSYNC;
@@ -362,7 +362,7 @@ void ntp_clear(void)
 
 	/* Clear PPS state variables */
 	pps_clear();
-	spin_unlock_irqrestore(&ntp_lock, flags);
+	raw_spin_unlock_irqrestore(&ntp_lock, flags);
 
 }
 
@@ -372,9 +372,9 @@ u64 ntp_tick_length(void)
 	unsigned long flags;
 	s64 ret;
 
-	spin_lock_irqsave(&ntp_lock, flags);
+	raw_spin_lock_irqsave(&ntp_lock, flags);
 	ret = tick_length;
-	spin_unlock_irqrestore(&ntp_lock, flags);
+	raw_spin_unlock_irqrestore(&ntp_lock, flags);
 	return ret;
 }
 
@@ -395,7 +395,7 @@ int second_overflow(unsigned long secs)
 	int leap = 0;
 	unsigned long flags;
 
-	spin_lock_irqsave(&ntp_lock, flags);
+	raw_spin_lock_irqsave(&ntp_lock, flags);
 
 	/*
 	 * Leap second processing. If in leap-insert state at the end of the
@@ -479,7 +479,7 @@ int second_overflow(unsigned long secs)
 	time_adjust = 0;
 
 out:
-	spin_unlock_irqrestore(&ntp_lock, flags);
+	raw_spin_unlock_irqrestore(&ntp_lock, flags);
 
 	return leap;
 }
@@ -672,7 +672,7 @@ int do_adjtimex(struct timex *txc)
 
 	getnstimeofday(&ts);
 
-	spin_lock_irq(&ntp_lock);
+	raw_spin_lock_irq(&ntp_lock);
 
 	if (txc->modes & ADJ_ADJTIME) {
 		long save_adjust = time_adjust;
@@ -714,7 +714,7 @@ int do_adjtimex(struct timex *txc)
 	/* fill PPS status fields */
 	pps_fill_timex(txc);
 
-	spin_unlock_irq(&ntp_lock);
+	raw_spin_unlock_irq(&ntp_lock);
 
 	txc->time.tv_sec = ts.tv_sec;
 	txc->time.tv_usec = ts.tv_nsec;
@@ -912,7 +912,7 @@ void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts)
 
 	pts_norm = pps_normalize_ts(*phase_ts);
 
-	spin_lock_irqsave(&ntp_lock, flags);
+	raw_spin_lock_irqsave(&ntp_lock, flags);
 
 	/* clear the error bits, they will be set again if needed */
 	time_status &= ~(STA_PPSJITTER | STA_PPSWANDER | STA_PPSERROR);
@@ -925,7 +925,7 @@ void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts)
 	 * just start the frequency interval */
 	if (unlikely(pps_fbase.tv_sec == 0)) {
 		pps_fbase = *raw_ts;
-		spin_unlock_irqrestore(&ntp_lock, flags);
+		raw_spin_unlock_irqrestore(&ntp_lock, flags);
 		return;
 	}
 
@@ -940,7 +940,7 @@ void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts)
 		time_status |= STA_PPSJITTER;
 		/* restart the frequency calibration interval */
 		pps_fbase = *raw_ts;
-		spin_unlock_irqrestore(&ntp_lock, flags);
+		raw_spin_unlock_irqrestore(&ntp_lock, flags);
 		pr_err("hardpps: PPSJITTER: bad pulse\n");
 		return;
 	}
@@ -957,7 +957,7 @@ void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts)
 
 	hardpps_update_phase(pts_norm.nsec);
 
-	spin_unlock_irqrestore(&ntp_lock, flags);
+	raw_spin_unlock_irqrestore(&ntp_lock, flags);
 }
 EXPORT_SYMBOL(hardpps);
 
diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 27689422aa92..4a944676358e 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -113,9 +113,9 @@ static int get_softlockup_thresh(void)
  * resolution, and we don't need to waste time with a big divide when
  * 2^30ns == 1.074s.
  */
-static unsigned long get_timestamp(int this_cpu)
+static unsigned long get_timestamp(void)
 {
-	return cpu_clock(this_cpu) >> 30LL;  /* 2^30 ~= 10^9 */
+	return local_clock() >> 30LL;  /* 2^30 ~= 10^9 */
 }
 
 static void set_sample_period(void)
@@ -133,9 +133,7 @@ static void set_sample_period(void)
 /* Commands for resetting the watchdog */
 static void __touch_watchdog(void)
 {
-	int this_cpu = smp_processor_id();
-
-	__this_cpu_write(watchdog_touch_ts, get_timestamp(this_cpu));
+	__this_cpu_write(watchdog_touch_ts, get_timestamp());
 }
 
 void touch_softlockup_watchdog(void)
@@ -196,7 +194,7 @@ static int is_hardlockup(void)
 
 static int is_softlockup(unsigned long touch_ts)
 {
-	unsigned long now = get_timestamp(smp_processor_id());
+	unsigned long now = get_timestamp();
 
 	/* Warn about unreasonable delays: */
 	if (time_after(now, touch_ts + get_softlockup_thresh()))
diff --git a/lib/locking-selftest.c b/lib/locking-selftest.c
index 7aae0f2a5e0a..c3eb261a7df3 100644
--- a/lib/locking-selftest.c
+++ b/lib/locking-selftest.c
@@ -47,10 +47,10 @@ __setup("debug_locks_verbose=", setup_debug_locks_verbose);
  * Normal standalone locks, for the circular and irq-context
  * dependency tests:
  */
-static DEFINE_SPINLOCK(lock_A);
-static DEFINE_SPINLOCK(lock_B);
-static DEFINE_SPINLOCK(lock_C);
-static DEFINE_SPINLOCK(lock_D);
+static DEFINE_RAW_SPINLOCK(lock_A);
+static DEFINE_RAW_SPINLOCK(lock_B);
+static DEFINE_RAW_SPINLOCK(lock_C);
+static DEFINE_RAW_SPINLOCK(lock_D);
 
 static DEFINE_RWLOCK(rwlock_A);
 static DEFINE_RWLOCK(rwlock_B);
@@ -73,12 +73,12 @@ static DECLARE_RWSEM(rwsem_D);
  * but X* and Y* are different classes. We do this so that
  * we do not trigger a real lockup:
  */
-static DEFINE_SPINLOCK(lock_X1);
-static DEFINE_SPINLOCK(lock_X2);
-static DEFINE_SPINLOCK(lock_Y1);
-static DEFINE_SPINLOCK(lock_Y2);
-static DEFINE_SPINLOCK(lock_Z1);
-static DEFINE_SPINLOCK(lock_Z2);
+static DEFINE_RAW_SPINLOCK(lock_X1);
+static DEFINE_RAW_SPINLOCK(lock_X2);
+static DEFINE_RAW_SPINLOCK(lock_Y1);
+static DEFINE_RAW_SPINLOCK(lock_Y2);
+static DEFINE_RAW_SPINLOCK(lock_Z1);
+static DEFINE_RAW_SPINLOCK(lock_Z2);
 
 static DEFINE_RWLOCK(rwlock_X1);
 static DEFINE_RWLOCK(rwlock_X2);
@@ -107,10 +107,10 @@ static DECLARE_RWSEM(rwsem_Z2);
  */
 #define INIT_CLASS_FUNC(class) 				\
 static noinline void					\
-init_class_##class(spinlock_t *lock, rwlock_t *rwlock, struct mutex *mutex, \
-		 struct rw_semaphore *rwsem)		\
+init_class_##class(raw_spinlock_t *lock, rwlock_t *rwlock, \
+	struct mutex *mutex, struct rw_semaphore *rwsem)\
 {							\
-	spin_lock_init(lock);				\
+	raw_spin_lock_init(lock);			\
 	rwlock_init(rwlock);				\
 	mutex_init(mutex);				\
 	init_rwsem(rwsem);				\
@@ -168,10 +168,10 @@ static void init_shared_classes(void)
  * Shortcuts for lock/unlock API variants, to keep
  * the testcases compact:
  */
-#define L(x)			spin_lock(&lock_##x)
-#define U(x)			spin_unlock(&lock_##x)
+#define L(x)			raw_spin_lock(&lock_##x)
+#define U(x)			raw_spin_unlock(&lock_##x)
 #define LU(x)			L(x); U(x)
-#define SI(x)			spin_lock_init(&lock_##x)
+#define SI(x)			raw_spin_lock_init(&lock_##x)
 
 #define WL(x)			write_lock(&rwlock_##x)
 #define WU(x)			write_unlock(&rwlock_##x)
@@ -911,7 +911,7 @@ GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_soft)
 
 #define I2(x)					\
 	do {					\
-		spin_lock_init(&lock_##x);	\
+		raw_spin_lock_init(&lock_##x);	\
 		rwlock_init(&rwlock_##x);	\
 		mutex_init(&mutex_##x);		\
 		init_rwsem(&rwsem_##x);		\
diff --git a/lib/rwsem-spinlock.c b/lib/rwsem-spinlock.c
index 7e0d6a58fc83..7542afbb22b3 100644
--- a/lib/rwsem-spinlock.c
+++ b/lib/rwsem-spinlock.c
@@ -73,20 +73,13 @@ __rwsem_do_wake(struct rw_semaphore *sem, int wakewrite)
 		goto dont_wake_writers;
 	}
 
-	/* if we are allowed to wake writers try to grant a single write lock
-	 * if there's a writer at the front of the queue
-	 * - we leave the 'waiting count' incremented to signify potential
-	 *   contention
+	/*
+	 * as we support write lock stealing, we can't set sem->activity
+	 * to -1 here to indicate we get the lock. Instead, we wake it up
+	 * to let it go get it again.
 	 */
 	if (waiter->flags & RWSEM_WAITING_FOR_WRITE) {
-		sem->activity = -1;
-		list_del(&waiter->list);
-		tsk = waiter->task;
-		/* Don't touch waiter after ->task has been NULLed */
-		smp_mb();
-		waiter->task = NULL;
-		wake_up_process(tsk);
-		put_task_struct(tsk);
+		wake_up_process(waiter->task);
 		goto out;
 	}
 
@@ -121,18 +114,10 @@ static inline struct rw_semaphore *
 __rwsem_wake_one_writer(struct rw_semaphore *sem)
 {
 	struct rwsem_waiter *waiter;
-	struct task_struct *tsk;
-
-	sem->activity = -1;
 
 	waiter = list_entry(sem->wait_list.next, struct rwsem_waiter, list);
-	list_del(&waiter->list);
+	wake_up_process(waiter->task);
 
-	tsk = waiter->task;
-	smp_mb();
-	waiter->task = NULL;
-	wake_up_process(tsk);
-	put_task_struct(tsk);
 	return sem;
 }
 
@@ -204,7 +189,6 @@ int __down_read_trylock(struct rw_semaphore *sem)
 
 /*
  * get a write lock on the semaphore
- * - we increment the waiting count anyway to indicate an exclusive lock
  */
 void __sched __down_write_nested(struct rw_semaphore *sem, int subclass)
 {
@@ -214,37 +198,32 @@ void __sched __down_write_nested(struct rw_semaphore *sem, int subclass)
 
 	raw_spin_lock_irqsave(&sem->wait_lock, flags);
 
-	if (sem->activity == 0 && list_empty(&sem->wait_list)) {
-		/* granted */
-		sem->activity = -1;
-		raw_spin_unlock_irqrestore(&sem->wait_lock, flags);
-		goto out;
-	}
-
-	tsk = current;
-	set_task_state(tsk, TASK_UNINTERRUPTIBLE);
-
 	/* set up my own style of waitqueue */
+	tsk = current;
 	waiter.task = tsk;
 	waiter.flags = RWSEM_WAITING_FOR_WRITE;
-	get_task_struct(tsk);
-
 	list_add_tail(&waiter.list, &sem->wait_list);
 
-	/* we don't need to touch the semaphore struct anymore */
-	raw_spin_unlock_irqrestore(&sem->wait_lock, flags);
-
-	/* wait to be given the lock */
+	/* wait for someone to release the lock */
 	for (;;) {
-		if (!waiter.task)
+		/*
+		 * That is the key to support write lock stealing: allows the
+		 * task already on CPU to get the lock soon rather than put
+		 * itself into sleep and waiting for system woke it or someone
+		 * else in the head of the wait list up.
+		 */
+		if (sem->activity == 0)
 			break;
-		schedule();
 		set_task_state(tsk, TASK_UNINTERRUPTIBLE);
+		raw_spin_unlock_irqrestore(&sem->wait_lock, flags);
+		schedule();
+		raw_spin_lock_irqsave(&sem->wait_lock, flags);
 	}
+	/* got the lock */
+	sem->activity = -1;
+	list_del(&waiter.list);
 
-	tsk->state = TASK_RUNNING;
- out:
-	;
+	raw_spin_unlock_irqrestore(&sem->wait_lock, flags);
 }
 
 void __sched __down_write(struct rw_semaphore *sem)
@@ -262,8 +241,8 @@ int __down_write_trylock(struct rw_semaphore *sem)
 
 	raw_spin_lock_irqsave(&sem->wait_lock, flags);
 
-	if (sem->activity == 0 && list_empty(&sem->wait_list)) {
-		/* granted */
+	if (sem->activity == 0) {
+		/* got the lock */
 		sem->activity = -1;
 		ret = 1;
 	}
diff --git a/lib/rwsem.c b/lib/rwsem.c
index 8337e1b9bb8d..ad5e0df16ab4 100644
--- a/lib/rwsem.c
+++ b/lib/rwsem.c
@@ -2,6 +2,8 @@
  *
  * Written by David Howells (dhowells@redhat.com).
  * Derived from arch/i386/kernel/semaphore.c
+ *
+ * Writer lock-stealing by Alex Shi <alex.shi@intel.com>
  */
 #include <linux/rwsem.h>
 #include <linux/sched.h>
@@ -60,7 +62,7 @@ __rwsem_do_wake(struct rw_semaphore *sem, int wake_type)
 	struct rwsem_waiter *waiter;
 	struct task_struct *tsk;
 	struct list_head *next;
-	signed long oldcount, woken, loop, adjustment;
+	signed long woken, loop, adjustment;
 
 	waiter = list_entry(sem->wait_list.next, struct rwsem_waiter, list);
 	if (!(waiter->flags & RWSEM_WAITING_FOR_WRITE))
@@ -72,30 +74,8 @@ __rwsem_do_wake(struct rw_semaphore *sem, int wake_type)
 		 */
 		goto out;
 
-	/* There's a writer at the front of the queue - try to grant it the
-	 * write lock.  However, we only wake this writer if we can transition
-	 * the active part of the count from 0 -> 1
-	 */
-	adjustment = RWSEM_ACTIVE_WRITE_BIAS;
-	if (waiter->list.next == &sem->wait_list)
-		adjustment -= RWSEM_WAITING_BIAS;
-
- try_again_write:
-	oldcount = rwsem_atomic_update(adjustment, sem) - adjustment;
-	if (oldcount & RWSEM_ACTIVE_MASK)
-		/* Someone grabbed the sem already */
-		goto undo_write;
-
-	/* We must be careful not to touch 'waiter' after we set ->task = NULL.
-	 * It is an allocated on the waiter's stack and may become invalid at
-	 * any time after that point (due to a wakeup from another source).
-	 */
-	list_del(&waiter->list);
-	tsk = waiter->task;
-	smp_mb();
-	waiter->task = NULL;
-	wake_up_process(tsk);
-	put_task_struct(tsk);
+	/* Wake up the writing waiter and let the task grab the sem: */
+	wake_up_process(waiter->task);
 	goto out;
 
  readers_only:
@@ -157,12 +137,40 @@ __rwsem_do_wake(struct rw_semaphore *sem, int wake_type)
 
  out:
 	return sem;
+}
+
+/* Try to get write sem, caller holds sem->wait_lock: */
+static int try_get_writer_sem(struct rw_semaphore *sem,
+					struct rwsem_waiter *waiter)
+{
+	struct rwsem_waiter *fwaiter;
+	long oldcount, adjustment;
 
-	/* undo the change to the active count, but check for a transition
-	 * 1->0 */
- undo_write:
+	/* only steal when first waiter is writing */
+	fwaiter = list_entry(sem->wait_list.next, struct rwsem_waiter, list);
+	if (!(fwaiter->flags & RWSEM_WAITING_FOR_WRITE))
+		return 0;
+
+	adjustment = RWSEM_ACTIVE_WRITE_BIAS;
+	/* Only one waiter in the queue: */
+	if (fwaiter == waiter && waiter->list.next == &sem->wait_list)
+		adjustment -= RWSEM_WAITING_BIAS;
+
+try_again_write:
+	oldcount = rwsem_atomic_update(adjustment, sem) - adjustment;
+	if (!(oldcount & RWSEM_ACTIVE_MASK)) {
+		/* No active lock: */
+		struct task_struct *tsk = waiter->task;
+
+		list_del(&waiter->list);
+		smp_mb();
+		put_task_struct(tsk);
+		tsk->state = TASK_RUNNING;
+		return 1;
+	}
+	/* some one grabbed the sem already */
 	if (rwsem_atomic_update(-adjustment, sem) & RWSEM_ACTIVE_MASK)
-		goto out;
+		return 0;
 	goto try_again_write;
 }
 
@@ -210,6 +218,15 @@ rwsem_down_failed_common(struct rw_semaphore *sem,
 	for (;;) {
 		if (!waiter.task)
 			break;
+
+		raw_spin_lock_irq(&sem->wait_lock);
+		/* Try to get the writer sem, may steal from the head writer: */
+		if (flags == RWSEM_WAITING_FOR_WRITE)
+			if (try_get_writer_sem(sem, &waiter)) {
+				raw_spin_unlock_irq(&sem->wait_lock);
+				return sem;
+			}
+		raw_spin_unlock_irq(&sem->wait_lock);
 		schedule();
 		set_task_state(tsk, TASK_UNINTERRUPTIBLE);
 	}