[GIT PULL] core/locking changes for v2.6.35

From: Ingo Molnar
Date: Mon May 17 2010 - 17:29:08 EST

Linus,

Please pull the latest core-locking-for-linus git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip.git core-locking-for-linus

Thanks,

Ingo

------------------>
Frederic Weisbecker (6):
lockstat: Make lockstat counting per cpu
lockdep: Fix redundant_hardirqs_on incremented with irqs enabled
lockdep: Simplify debug atomic ops
lockdep: Provide off case for redundant_hardirqs_on increment
lockdep: Actually _dec_ in debug_atomic_dec
lockdep: No need to disable preemption in debug atomic ops

Thomas Gleixner (1):
i8253: Convert i8253_lock to raw_spinlock

Tony Breeds (1):
mutex: Fix optimistic spinning vs. BKL

Yong Zhang (1):
lockdep: Reduce stack_trace usage


arch/mips/include/asm/i8253.h | 2 +-
arch/mips/kernel/i8253.c | 14 +++---
arch/x86/include/asm/i8253.h | 2 +-
arch/x86/kernel/apm_32.c | 4 +-
arch/x86/kernel/i8253.c | 14 +++---
drivers/block/hd.c | 4 +-
drivers/input/gameport/gameport.c | 4 +-
drivers/input/joystick/analog.c | 4 +-
drivers/input/misc/pcspkr.c | 6 +-
include/linux/sched.h | 3 +-
kernel/lockdep.c | 81 +++++++++++++++++++-----------------
kernel/lockdep_internals.h | 72 +++++++++++++++++++++++----------
kernel/lockdep_proc.c | 58 +++++++++++++-------------
kernel/mutex.c | 12 +++++-
kernel/sched.c | 5 +-
sound/drivers/pcsp/pcsp.h | 2 +-
sound/drivers/pcsp/pcsp_input.c | 4 +-
sound/drivers/pcsp/pcsp_lib.c | 12 +++---
18 files changed, 174 insertions(+), 129 deletions(-)

diff --git a/arch/mips/include/asm/i8253.h b/arch/mips/include/asm/i8253.h
index 032ca73..48bb823 100644
--- a/arch/mips/include/asm/i8253.h
+++ b/arch/mips/include/asm/i8253.h
@@ -12,7 +12,7 @@
#define PIT_CH0 0x40
#define PIT_CH2 0x42

-extern spinlock_t i8253_lock;
+extern raw_spinlock_t i8253_lock;

extern void setup_pit_timer(void);

diff --git a/arch/mips/kernel/i8253.c b/arch/mips/kernel/i8253.c
index ed5c441..9479406 100644
--- a/arch/mips/kernel/i8253.c
+++ b/arch/mips/kernel/i8253.c
@@ -15,7 +15,7 @@
#include <asm/io.h>
#include <asm/time.h>

-DEFINE_SPINLOCK(i8253_lock);
+DEFINE_RAW_SPINLOCK(i8253_lock);
EXPORT_SYMBOL(i8253_lock);

/*
@@ -26,7 +26,7 @@ EXPORT_SYMBOL(i8253_lock);
static void init_pit_timer(enum clock_event_mode mode,
struct clock_event_device *evt)
{
- spin_lock(&i8253_lock);
+ raw_spin_lock(&i8253_lock);

switch(mode) {
case CLOCK_EVT_MODE_PERIODIC:
@@ -55,7 +55,7 @@ static void init_pit_timer(enum clock_event_mode mode,
/* Nothing to do here */
break;
}
- spin_unlock(&i8253_lock);
+ raw_spin_unlock(&i8253_lock);
}

/*
@@ -65,10 +65,10 @@ static void init_pit_timer(enum clock_event_mode mode,
*/
static int pit_next_event(unsigned long delta, struct clock_event_device *evt)
{
- spin_lock(&i8253_lock);
+ raw_spin_lock(&i8253_lock);
outb_p(delta & 0xff , PIT_CH0); /* LSB */
outb(delta >> 8 , PIT_CH0); /* MSB */
- spin_unlock(&i8253_lock);
+ raw_spin_unlock(&i8253_lock);

return 0;
}
@@ -137,7 +137,7 @@ static cycle_t pit_read(struct clocksource *cs)
static int old_count;
static u32 old_jifs;

- spin_lock_irqsave(&i8253_lock, flags);
+ raw_spin_lock_irqsave(&i8253_lock, flags);
/*
* Although our caller may have the read side of xtime_lock,
* this is now a seqlock, and we are cheating in this routine
@@ -183,7 +183,7 @@ static cycle_t pit_read(struct clocksource *cs)
old_count = count;
old_jifs = jifs;

- spin_unlock_irqrestore(&i8253_lock, flags);
+ raw_spin_unlock_irqrestore(&i8253_lock, flags);

count = (LATCH - 1) - count;

diff --git a/arch/x86/include/asm/i8253.h b/arch/x86/include/asm/i8253.h
index 1edbf89..fc1f579 100644
--- a/arch/x86/include/asm/i8253.h
+++ b/arch/x86/include/asm/i8253.h
@@ -6,7 +6,7 @@
#define PIT_CH0 0x40
#define PIT_CH2 0x42

-extern spinlock_t i8253_lock;
+extern raw_spinlock_t i8253_lock;

extern struct clock_event_device *global_clock_event;

diff --git a/arch/x86/kernel/apm_32.c b/arch/x86/kernel/apm_32.c
index 031aa88..c4f9182 100644
--- a/arch/x86/kernel/apm_32.c
+++ b/arch/x86/kernel/apm_32.c
@@ -1224,7 +1224,7 @@ static void reinit_timer(void)
#ifdef INIT_TIMER_AFTER_SUSPEND
unsigned long flags;

- spin_lock_irqsave(&i8253_lock, flags);
+ raw_spin_lock_irqsave(&i8253_lock, flags);
/* set the clock to HZ */
outb_pit(0x34, PIT_MODE); /* binary, mode 2, LSB/MSB, ch 0 */
udelay(10);
@@ -1232,7 +1232,7 @@ static void reinit_timer(void)
udelay(10);
outb_pit(LATCH >> 8, PIT_CH0); /* MSB */
udelay(10);
- spin_unlock_irqrestore(&i8253_lock, flags);
+ raw_spin_unlock_irqrestore(&i8253_lock, flags);
#endif
}

diff --git a/arch/x86/kernel/i8253.c b/arch/x86/kernel/i8253.c
index 23c1679..2dfd315 100644
--- a/arch/x86/kernel/i8253.c
+++ b/arch/x86/kernel/i8253.c
@@ -16,7 +16,7 @@
#include <asm/hpet.h>
#include <asm/smp.h>

-DEFINE_SPINLOCK(i8253_lock);
+DEFINE_RAW_SPINLOCK(i8253_lock);
EXPORT_SYMBOL(i8253_lock);

/*
@@ -33,7 +33,7 @@ struct clock_event_device *global_clock_event;
static void init_pit_timer(enum clock_event_mode mode,
struct clock_event_device *evt)
{
- spin_lock(&i8253_lock);
+ raw_spin_lock(&i8253_lock);

switch (mode) {
case CLOCK_EVT_MODE_PERIODIC:
@@ -62,7 +62,7 @@ static void init_pit_timer(enum clock_event_mode mode,
/* Nothing to do here */
break;
}
- spin_unlock(&i8253_lock);
+ raw_spin_unlock(&i8253_lock);
}

/*
@@ -72,10 +72,10 @@ static void init_pit_timer(enum clock_event_mode mode,
*/
static int pit_next_event(unsigned long delta, struct clock_event_device *evt)
{
- spin_lock(&i8253_lock);
+ raw_spin_lock(&i8253_lock);
outb_pit(delta & 0xff , PIT_CH0); /* LSB */
outb_pit(delta >> 8 , PIT_CH0); /* MSB */
- spin_unlock(&i8253_lock);
+ raw_spin_unlock(&i8253_lock);

return 0;
}
@@ -130,7 +130,7 @@ static cycle_t pit_read(struct clocksource *cs)
int count;
u32 jifs;

- spin_lock_irqsave(&i8253_lock, flags);
+ raw_spin_lock_irqsave(&i8253_lock, flags);
/*
* Although our caller may have the read side of xtime_lock,
* this is now a seqlock, and we are cheating in this routine
@@ -176,7 +176,7 @@ static cycle_t pit_read(struct clocksource *cs)
old_count = count;
old_jifs = jifs;

- spin_unlock_irqrestore(&i8253_lock, flags);
+ raw_spin_unlock_irqrestore(&i8253_lock, flags);

count = (LATCH - 1) - count;

diff --git a/drivers/block/hd.c b/drivers/block/hd.c
index 034e6df..81c78b3 100644
--- a/drivers/block/hd.c
+++ b/drivers/block/hd.c
@@ -164,12 +164,12 @@ unsigned long read_timer(void)
unsigned long t, flags;
int i;

- spin_lock_irqsave(&i8253_lock, flags);
+ raw_spin_lock_irqsave(&i8253_lock, flags);
t = jiffies * 11932;
outb_p(0, 0x43);
i = inb_p(0x40);
i |= inb(0x40) << 8;
- spin_unlock_irqrestore(&i8253_lock, flags);
+ raw_spin_unlock_irqrestore(&i8253_lock, flags);
return(t - i);
}
#endif
diff --git a/drivers/input/gameport/gameport.c b/drivers/input/gameport/gameport.c
index 7e18bcf..46239e4 100644
--- a/drivers/input/gameport/gameport.c
+++ b/drivers/input/gameport/gameport.c
@@ -59,11 +59,11 @@ static unsigned int get_time_pit(void)
unsigned long flags;
unsigned int count;

- spin_lock_irqsave(&i8253_lock, flags);
+ raw_spin_lock_irqsave(&i8253_lock, flags);
outb_p(0x00, 0x43);
count = inb_p(0x40);
count |= inb_p(0x40) << 8;
- spin_unlock_irqrestore(&i8253_lock, flags);
+ raw_spin_unlock_irqrestore(&i8253_lock, flags);

return count;
}
diff --git a/drivers/input/joystick/analog.c b/drivers/input/joystick/analog.c
index 1c0b529..4afe0a3 100644
--- a/drivers/input/joystick/analog.c
+++ b/drivers/input/joystick/analog.c
@@ -146,11 +146,11 @@ static unsigned int get_time_pit(void)
unsigned long flags;
unsigned int count;

- spin_lock_irqsave(&i8253_lock, flags);
+ raw_spin_lock_irqsave(&i8253_lock, flags);
outb_p(0x00, 0x43);
count = inb_p(0x40);
count |= inb_p(0x40) << 8;
- spin_unlock_irqrestore(&i8253_lock, flags);
+ raw_spin_unlock_irqrestore(&i8253_lock, flags);

return count;
}
diff --git a/drivers/input/misc/pcspkr.c b/drivers/input/misc/pcspkr.c
index ea4e1fd..f080dd3 100644
--- a/drivers/input/misc/pcspkr.c
+++ b/drivers/input/misc/pcspkr.c
@@ -30,7 +30,7 @@ MODULE_ALIAS("platform:pcspkr");
#include <asm/i8253.h>
#else
#include <asm/8253pit.h>
-static DEFINE_SPINLOCK(i8253_lock);
+static DEFINE_RAW_SPINLOCK(i8253_lock);
#endif

static int pcspkr_event(struct input_dev *dev, unsigned int type, unsigned int code, int value)
@@ -50,7 +50,7 @@ static int pcspkr_event(struct input_dev *dev, unsigned int type, unsigned int c
if (value > 20 && value < 32767)
count = PIT_TICK_RATE / value;

- spin_lock_irqsave(&i8253_lock, flags);
+ raw_spin_lock_irqsave(&i8253_lock, flags);

if (count) {
/* set command for counter 2, 2 byte write */
@@ -65,7 +65,7 @@ static int pcspkr_event(struct input_dev *dev, unsigned int type, unsigned int c
outb(inb_p(0x61) & 0xFC, 0x61);
}

- spin_unlock_irqrestore(&i8253_lock, flags);
+ raw_spin_unlock_irqrestore(&i8253_lock, flags);

return 0;
}
diff --git a/include/linux/sched.h b/include/linux/sched.h
index dad7f66..bc6bd9a 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -361,7 +361,8 @@ extern signed long schedule_timeout_interruptible(signed long timeout);
extern signed long schedule_timeout_killable(signed long timeout);
extern signed long schedule_timeout_uninterruptible(signed long timeout);
asmlinkage void schedule(void);
-extern int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner);
+extern int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner,
+ unsigned long timeout);

struct nsproxy;
struct user_namespace;
diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index 2594e1c..5108080 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -431,20 +431,7 @@ static struct stack_trace lockdep_init_trace = {
/*
* Various lockdep statistics:
*/
-atomic_t chain_lookup_hits;
-atomic_t chain_lookup_misses;
-atomic_t hardirqs_on_events;
-atomic_t hardirqs_off_events;
-atomic_t redundant_hardirqs_on;
-atomic_t redundant_hardirqs_off;
-atomic_t softirqs_on_events;
-atomic_t softirqs_off_events;
-atomic_t redundant_softirqs_on;
-atomic_t redundant_softirqs_off;
-atomic_t nr_unused_locks;
-atomic_t nr_cyclic_checks;
-atomic_t nr_find_usage_forwards_checks;
-atomic_t nr_find_usage_backwards_checks;
+DEFINE_PER_CPU(struct lockdep_stats, lockdep_stats);
#endif

/*
@@ -748,7 +735,7 @@ register_lock_class(struct lockdep_map *lock, unsigned int subclass, int force)
return NULL;
}
class = lock_classes + nr_lock_classes++;
- debug_atomic_inc(&nr_unused_locks);
+ debug_atomic_inc(nr_unused_locks);
class->key = key;
class->name = lock->name;
class->subclass = subclass;
@@ -818,7 +805,8 @@ static struct lock_list *alloc_list_entry(void)
* Add a new dependency to the head of the list:
*/
static int add_lock_to_list(struct lock_class *class, struct lock_class *this,
- struct list_head *head, unsigned long ip, int distance)
+ struct list_head *head, unsigned long ip,
+ int distance, struct stack_trace *trace)
{
struct lock_list *entry;
/*
@@ -829,11 +817,9 @@ static int add_lock_to_list(struct lock_class *class, struct lock_class *this,
if (!entry)
return 0;

- if (!save_trace(&entry->trace))
- return 0;
-
entry->class = this;
entry->distance = distance;
+ entry->trace = *trace;
/*
* Since we never remove from the dependency list, the list can
* be walked lockless by other CPUs, it's only allocation
@@ -1205,7 +1191,7 @@ check_noncircular(struct lock_list *root, struct lock_class *target,
{
int result;

- debug_atomic_inc(&nr_cyclic_checks);
+ debug_atomic_inc(nr_cyclic_checks);

result = __bfs_forwards(root, target, class_equal, target_entry);

@@ -1242,7 +1228,7 @@ find_usage_forwards(struct lock_list *root, enum lock_usage_bit bit,
{
int result;

- debug_atomic_inc(&nr_find_usage_forwards_checks);
+ debug_atomic_inc(nr_find_usage_forwards_checks);

result = __bfs_forwards(root, (void *)bit, usage_match, target_entry);

@@ -1265,7 +1251,7 @@ find_usage_backwards(struct lock_list *root, enum lock_usage_bit bit,
{
int result;

- debug_atomic_inc(&nr_find_usage_backwards_checks);
+ debug_atomic_inc(nr_find_usage_backwards_checks);

result = __bfs_backwards(root, (void *)bit, usage_match, target_entry);

@@ -1635,12 +1621,20 @@ check_deadlock(struct task_struct *curr, struct held_lock *next,
*/
static int
check_prev_add(struct task_struct *curr, struct held_lock *prev,
- struct held_lock *next, int distance)
+ struct held_lock *next, int distance, int trylock_loop)
{
struct lock_list *entry;
int ret;
struct lock_list this;
struct lock_list *uninitialized_var(target_entry);
+ /*
+ * Static variable, serialized by the graph_lock().
+ *
+ * We use this static variable to save the stack trace in case
+ * we call into this function multiple times due to encountering
+ * trylocks in the held lock stack.
+ */
+ static struct stack_trace trace;

/*
* Prove that the new <prev> -> <next> dependency would not
@@ -1688,20 +1682,23 @@ check_prev_add(struct task_struct *curr, struct held_lock *prev,
}
}

+ if (!trylock_loop && !save_trace(&trace))
+ return 0;
+
/*
* Ok, all validations passed, add the new lock
* to the previous lock's dependency list:
*/
ret = add_lock_to_list(hlock_class(prev), hlock_class(next),
&hlock_class(prev)->locks_after,
- next->acquire_ip, distance);
+ next->acquire_ip, distance, &trace);

if (!ret)
return 0;

ret = add_lock_to_list(hlock_class(next), hlock_class(prev),
&hlock_class(next)->locks_before,
- next->acquire_ip, distance);
+ next->acquire_ip, distance, &trace);
if (!ret)
return 0;

@@ -1731,6 +1728,7 @@ static int
check_prevs_add(struct task_struct *curr, struct held_lock *next)
{
int depth = curr->lockdep_depth;
+ int trylock_loop = 0;
struct held_lock *hlock;

/*
@@ -1756,7 +1754,8 @@ check_prevs_add(struct task_struct *curr, struct held_lock *next)
* added:
*/
if (hlock->read != 2) {
- if (!check_prev_add(curr, hlock, next, distance))
+ if (!check_prev_add(curr, hlock, next,
+ distance, trylock_loop))
return 0;
/*
* Stop after the first non-trylock entry,
@@ -1779,6 +1778,7 @@ check_prevs_add(struct task_struct *curr, struct held_lock *next)
if (curr->held_locks[depth].irq_context !=
curr->held_locks[depth-1].irq_context)
break;
+ trylock_loop = 1;
}
return 1;
out_bug:
@@ -1825,7 +1825,7 @@ static inline int lookup_chain_cache(struct task_struct *curr,
list_for_each_entry(chain, hash_head, entry) {
if (chain->chain_key == chain_key) {
cache_hit:
- debug_atomic_inc(&chain_lookup_hits);
+ debug_atomic_inc(chain_lookup_hits);
if (very_verbose(class))
printk("\nhash chain already cached, key: "
"%016Lx tail class: [%p] %s\n",
@@ -1890,7 +1890,7 @@ cache_hit:
chain_hlocks[chain->base + j] = class - lock_classes;
}
list_add_tail_rcu(&chain->entry, hash_head);
- debug_atomic_inc(&chain_lookup_misses);
+ debug_atomic_inc(chain_lookup_misses);
inc_chains();

return 1;
@@ -2311,7 +2311,12 @@ void trace_hardirqs_on_caller(unsigned long ip)
return;

if (unlikely(curr->hardirqs_enabled)) {
- debug_atomic_inc(&redundant_hardirqs_on);
+ /*
+ * Neither irq nor preemption are disabled here
+ * so this is racy by nature but loosing one hit
+ * in a stat is not a big deal.
+ */
+ __debug_atomic_inc(redundant_hardirqs_on);
return;
}
/* we'll do an OFF -> ON transition: */
@@ -2338,7 +2343,7 @@ void trace_hardirqs_on_caller(unsigned long ip)

curr->hardirq_enable_ip = ip;
curr->hardirq_enable_event = ++curr->irq_events;
- debug_atomic_inc(&hardirqs_on_events);
+ debug_atomic_inc(hardirqs_on_events);
}
EXPORT_SYMBOL(trace_hardirqs_on_caller);

@@ -2370,9 +2375,9 @@ void trace_hardirqs_off_caller(unsigned long ip)
curr->hardirqs_enabled = 0;
curr->hardirq_disable_ip = ip;
curr->hardirq_disable_event = ++curr->irq_events;
- debug_atomic_inc(&hardirqs_off_events);
+ debug_atomic_inc(hardirqs_off_events);
} else
- debug_atomic_inc(&redundant_hardirqs_off);
+ debug_atomic_inc(redundant_hardirqs_off);
}
EXPORT_SYMBOL(trace_hardirqs_off_caller);

@@ -2396,7 +2401,7 @@ void trace_softirqs_on(unsigned long ip)
return;

if (curr->softirqs_enabled) {
- debug_atomic_inc(&redundant_softirqs_on);
+ debug_atomic_inc(redundant_softirqs_on);
return;
}

@@ -2406,7 +2411,7 @@ void trace_softirqs_on(unsigned long ip)
curr->softirqs_enabled = 1;
curr->softirq_enable_ip = ip;
curr->softirq_enable_event = ++curr->irq_events;
- debug_atomic_inc(&softirqs_on_events);
+ debug_atomic_inc(softirqs_on_events);
/*
* We are going to turn softirqs on, so set the
* usage bit for all held locks, if hardirqs are
@@ -2436,10 +2441,10 @@ void trace_softirqs_off(unsigned long ip)
curr->softirqs_enabled = 0;
curr->softirq_disable_ip = ip;
curr->softirq_disable_event = ++curr->irq_events;
- debug_atomic_inc(&softirqs_off_events);
+ debug_atomic_inc(softirqs_off_events);
DEBUG_LOCKS_WARN_ON(!softirq_count());
} else
- debug_atomic_inc(&redundant_softirqs_off);
+ debug_atomic_inc(redundant_softirqs_off);
}

static void __lockdep_trace_alloc(gfp_t gfp_mask, unsigned long flags)
@@ -2644,7 +2649,7 @@ static int mark_lock(struct task_struct *curr, struct held_lock *this,
return 0;
break;
case LOCK_USED:
- debug_atomic_dec(&nr_unused_locks);
+ debug_atomic_dec(nr_unused_locks);
break;
default:
if (!debug_locks_off_graph_unlock())
@@ -2750,7 +2755,7 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
if (!class)
return 0;
}
- debug_atomic_inc((atomic_t *)&class->ops);
+ atomic_inc((atomic_t *)&class->ops);
if (very_verbose(class)) {
printk("\nacquire class [%p] %s", class->key, class->name);
if (class->name_version > 1)
diff --git a/kernel/lockdep_internals.h b/kernel/lockdep_internals.h
index a2ee95a..4f560cf 100644
--- a/kernel/lockdep_internals.h
+++ b/kernel/lockdep_internals.h
@@ -110,30 +110,60 @@ lockdep_count_backward_deps(struct lock_class *class)
#endif

#ifdef CONFIG_DEBUG_LOCKDEP
+
+#include <asm/local.h>
/*
- * Various lockdep statistics:
+ * Various lockdep statistics.
+ * We want them per cpu as they are often accessed in fast path
+ * and we want to avoid too much cache bouncing.
*/
-extern atomic_t chain_lookup_hits;
-extern atomic_t chain_lookup_misses;
-extern atomic_t hardirqs_on_events;
-extern atomic_t hardirqs_off_events;
-extern atomic_t redundant_hardirqs_on;
-extern atomic_t redundant_hardirqs_off;
-extern atomic_t softirqs_on_events;
-extern atomic_t softirqs_off_events;
-extern atomic_t redundant_softirqs_on;
-extern atomic_t redundant_softirqs_off;
-extern atomic_t nr_unused_locks;
-extern atomic_t nr_cyclic_checks;
-extern atomic_t nr_cyclic_check_recursions;
-extern atomic_t nr_find_usage_forwards_checks;
-extern atomic_t nr_find_usage_forwards_recursions;
-extern atomic_t nr_find_usage_backwards_checks;
-extern atomic_t nr_find_usage_backwards_recursions;
-# define debug_atomic_inc(ptr) atomic_inc(ptr)
-# define debug_atomic_dec(ptr) atomic_dec(ptr)
-# define debug_atomic_read(ptr) atomic_read(ptr)
+struct lockdep_stats {
+ int chain_lookup_hits;
+ int chain_lookup_misses;
+ int hardirqs_on_events;
+ int hardirqs_off_events;
+ int redundant_hardirqs_on;
+ int redundant_hardirqs_off;
+ int softirqs_on_events;
+ int softirqs_off_events;
+ int redundant_softirqs_on;
+ int redundant_softirqs_off;
+ int nr_unused_locks;
+ int nr_cyclic_checks;
+ int nr_cyclic_check_recursions;
+ int nr_find_usage_forwards_checks;
+ int nr_find_usage_forwards_recursions;
+ int nr_find_usage_backwards_checks;
+ int nr_find_usage_backwards_recursions;
+};
+
+DECLARE_PER_CPU(struct lockdep_stats, lockdep_stats);
+
+#define __debug_atomic_inc(ptr) \
+ this_cpu_inc(lockdep_stats.ptr);
+
+#define debug_atomic_inc(ptr) { \
+ WARN_ON_ONCE(!irqs_disabled()); \
+ __this_cpu_inc(lockdep_stats.ptr); \
+}
+
+#define debug_atomic_dec(ptr) { \
+ WARN_ON_ONCE(!irqs_disabled()); \
+ __this_cpu_dec(lockdep_stats.ptr); \
+}
+
+#define debug_atomic_read(ptr) ({ \
+ struct lockdep_stats *__cpu_lockdep_stats; \
+ unsigned long long __total = 0; \
+ int __cpu; \
+ for_each_possible_cpu(__cpu) { \
+ __cpu_lockdep_stats = &per_cpu(lockdep_stats, __cpu); \
+ __total += __cpu_lockdep_stats->ptr; \
+ } \
+ __total; \
+})
#else
+# define __debug_atomic_inc(ptr) do { } while (0)
# define debug_atomic_inc(ptr) do { } while (0)
# define debug_atomic_dec(ptr) do { } while (0)
# define debug_atomic_read(ptr) 0
diff --git a/kernel/lockdep_proc.c b/kernel/lockdep_proc.c
index d4aba4f..59b76c8 100644
--- a/kernel/lockdep_proc.c
+++ b/kernel/lockdep_proc.c
@@ -184,34 +184,34 @@ static const struct file_operations proc_lockdep_chains_operations = {
static void lockdep_stats_debug_show(struct seq_file *m)
{
#ifdef CONFIG_DEBUG_LOCKDEP
- unsigned int hi1 = debug_atomic_read(&hardirqs_on_events),
- hi2 = debug_atomic_read(&hardirqs_off_events),
- hr1 = debug_atomic_read(&redundant_hardirqs_on),
- hr2 = debug_atomic_read(&redundant_hardirqs_off),
- si1 = debug_atomic_read(&softirqs_on_events),
- si2 = debug_atomic_read(&softirqs_off_events),
- sr1 = debug_atomic_read(&redundant_softirqs_on),
- sr2 = debug_atomic_read(&redundant_softirqs_off);
-
- seq_printf(m, " chain lookup misses: %11u\n",
- debug_atomic_read(&chain_lookup_misses));
- seq_printf(m, " chain lookup hits: %11u\n",
- debug_atomic_read(&chain_lookup_hits));
- seq_printf(m, " cyclic checks: %11u\n",
- debug_atomic_read(&nr_cyclic_checks));
- seq_printf(m, " find-mask forwards checks: %11u\n",
- debug_atomic_read(&nr_find_usage_forwards_checks));
- seq_printf(m, " find-mask backwards checks: %11u\n",
- debug_atomic_read(&nr_find_usage_backwards_checks));
-
- seq_printf(m, " hardirq on events: %11u\n", hi1);
- seq_printf(m, " hardirq off events: %11u\n", hi2);
- seq_printf(m, " redundant hardirq ons: %11u\n", hr1);
- seq_printf(m, " redundant hardirq offs: %11u\n", hr2);
- seq_printf(m, " softirq on events: %11u\n", si1);
- seq_printf(m, " softirq off events: %11u\n", si2);
- seq_printf(m, " redundant softirq ons: %11u\n", sr1);
- seq_printf(m, " redundant softirq offs: %11u\n", sr2);
+ unsigned long long hi1 = debug_atomic_read(hardirqs_on_events),
+ hi2 = debug_atomic_read(hardirqs_off_events),
+ hr1 = debug_atomic_read(redundant_hardirqs_on),
+ hr2 = debug_atomic_read(redundant_hardirqs_off),
+ si1 = debug_atomic_read(softirqs_on_events),
+ si2 = debug_atomic_read(softirqs_off_events),
+ sr1 = debug_atomic_read(redundant_softirqs_on),
+ sr2 = debug_atomic_read(redundant_softirqs_off);
+
+ seq_printf(m, " chain lookup misses: %11llu\n",
+ debug_atomic_read(chain_lookup_misses));
+ seq_printf(m, " chain lookup hits: %11llu\n",
+ debug_atomic_read(chain_lookup_hits));
+ seq_printf(m, " cyclic checks: %11llu\n",
+ debug_atomic_read(nr_cyclic_checks));
+ seq_printf(m, " find-mask forwards checks: %11llu\n",
+ debug_atomic_read(nr_find_usage_forwards_checks));
+ seq_printf(m, " find-mask backwards checks: %11llu\n",
+ debug_atomic_read(nr_find_usage_backwards_checks));
+
+ seq_printf(m, " hardirq on events: %11llu\n", hi1);
+ seq_printf(m, " hardirq off events: %11llu\n", hi2);
+ seq_printf(m, " redundant hardirq ons: %11llu\n", hr1);
+ seq_printf(m, " redundant hardirq offs: %11llu\n", hr2);
+ seq_printf(m, " softirq on events: %11llu\n", si1);
+ seq_printf(m, " softirq off events: %11llu\n", si2);
+ seq_printf(m, " redundant softirq ons: %11llu\n", sr1);
+ seq_printf(m, " redundant softirq offs: %11llu\n", sr2);
#endif
}

@@ -263,7 +263,7 @@ static int lockdep_stats_show(struct seq_file *m, void *v)
#endif
}
#ifdef CONFIG_DEBUG_LOCKDEP
- DEBUG_LOCKS_WARN_ON(debug_atomic_read(&nr_unused_locks) != nr_unused);
+ DEBUG_LOCKS_WARN_ON(debug_atomic_read(nr_unused_locks) != nr_unused);
#endif
seq_printf(m, " lock-classes: %11lu [max: %lu]\n",
nr_lock_classes, MAX_LOCKDEP_KEYS);
diff --git a/kernel/mutex.c b/kernel/mutex.c
index 632f04c..7d4626b 100644
--- a/kernel/mutex.c
+++ b/kernel/mutex.c
@@ -145,6 +145,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
struct task_struct *task = current;
struct mutex_waiter waiter;
unsigned long flags;
+ unsigned long timeout;

preempt_disable();
mutex_acquire(&lock->dep_map, subclass, 0, ip);
@@ -168,15 +169,22 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
* to serialize everything.
*/

- for (;;) {
+ for (timeout = jiffies + 2; time_before(jiffies, timeout);) {
struct thread_info *owner;

/*
+ * If we own the BKL, then don't spin. The owner of the mutex
+ * might be waiting on us to release the BKL.
+ */
+ if (current->lock_depth >= 0)
+ break;
+
+ /*
* If there's an owner, wait for it to either
* release the lock or go to sleep.
*/
owner = ACCESS_ONCE(lock->owner);
- if (owner && !mutex_spin_on_owner(lock, owner))
+ if (owner && !mutex_spin_on_owner(lock, owner, timeout))
break;

if (atomic_cmpxchg(&lock->count, 1, 0) == 1) {
diff --git a/kernel/sched.c b/kernel/sched.c
index 3c2a54f..e613160 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -3775,7 +3775,8 @@ EXPORT_SYMBOL(schedule);
* Look out! "owner" is an entirely speculative pointer
* access and not reliable.
*/
-int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner)
+int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner,
+ unsigned long timeout)
{
unsigned int cpu;
struct rq *rq;
@@ -3811,7 +3812,7 @@ int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner)

rq = cpu_rq(cpu);

- for (;;) {
+ while (time_before(jiffies, timeout)) {
/*
* Owner changed, break to re-assess state.
*/
diff --git a/sound/drivers/pcsp/pcsp.h b/sound/drivers/pcsp/pcsp.h
index 1e12307..4ff6c8c 100644
--- a/sound/drivers/pcsp/pcsp.h
+++ b/sound/drivers/pcsp/pcsp.h
@@ -16,7 +16,7 @@
#include <asm/i8253.h>
#else
#include <asm/8253pit.h>
-static DEFINE_SPINLOCK(i8253_lock);
+static DEFINE_RAW_SPINLOCK(i8253_lock);
#endif

#define PCSP_SOUND_VERSION 0x400 /* read 4.00 */
diff --git a/sound/drivers/pcsp/pcsp_input.c b/sound/drivers/pcsp/pcsp_input.c
index 0444cde..b5e2b54 100644
--- a/sound/drivers/pcsp/pcsp_input.c
+++ b/sound/drivers/pcsp/pcsp_input.c
@@ -21,7 +21,7 @@ static void pcspkr_do_sound(unsigned int count)
{
unsigned long flags;

- spin_lock_irqsave(&i8253_lock, flags);
+ raw_spin_lock_irqsave(&i8253_lock, flags);

if (count) {
/* set command for counter 2, 2 byte write */
@@ -36,7 +36,7 @@ static void pcspkr_do_sound(unsigned int count)
outb(inb_p(0x61) & 0xFC, 0x61);
}

- spin_unlock_irqrestore(&i8253_lock, flags);
+ raw_spin_unlock_irqrestore(&i8253_lock, flags);
}

void pcspkr_stop_sound(void)
diff --git a/sound/drivers/pcsp/pcsp_lib.c b/sound/drivers/pcsp/pcsp_lib.c
index d77ffa9..ce9e7d1 100644
--- a/sound/drivers/pcsp/pcsp_lib.c
+++ b/sound/drivers/pcsp/pcsp_lib.c
@@ -66,7 +66,7 @@ static u64 pcsp_timer_update(struct snd_pcsp *chip)
timer_cnt = val * CUR_DIV() / 256;

if (timer_cnt && chip->enable) {
- spin_lock_irqsave(&i8253_lock, flags);
+ raw_spin_lock_irqsave(&i8253_lock, flags);
if (!nforce_wa) {
outb_p(chip->val61, 0x61);
outb_p(timer_cnt, 0x42);
@@ -75,7 +75,7 @@ static u64 pcsp_timer_update(struct snd_pcsp *chip)
outb(chip->val61 ^ 2, 0x61);
chip->thalf = 1;
}
- spin_unlock_irqrestore(&i8253_lock, flags);
+ raw_spin_unlock_irqrestore(&i8253_lock, flags);
}

chip->ns_rem = PCSP_PERIOD_NS();
@@ -159,10 +159,10 @@ static int pcsp_start_playing(struct snd_pcsp *chip)
return -EIO;
}

- spin_lock(&i8253_lock);
+ raw_spin_lock(&i8253_lock);
chip->val61 = inb(0x61) | 0x03;
outb_p(0x92, 0x43); /* binary, mode 1, LSB only, ch 2 */
- spin_unlock(&i8253_lock);
+ raw_spin_unlock(&i8253_lock);
atomic_set(&chip->timer_active, 1);
chip->thalf = 0;

@@ -179,11 +179,11 @@ static void pcsp_stop_playing(struct snd_pcsp *chip)
return;

atomic_set(&chip->timer_active, 0);
- spin_lock(&i8253_lock);
+ raw_spin_lock(&i8253_lock);
/* restore the timer */
outb_p(0xb6, 0x43); /* binary, mode 3, LSB/MSB, ch 2 */
outb(chip->val61 & 0xFC, 0x61);
- spin_unlock(&i8253_lock);
+ raw_spin_unlock(&i8253_lock);
}

/*
--
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