The "int check" argument of lock_acquire() and held_lock->check
are misleading and unneeded. This is only used as a boolean, 2
denotes "true", everything else is "false". And this boolean is
always equal to prove_locking.
The only exception is __lockdep_no_validate__ which should make
this condition "false" in validate_chain().
This patch kills this member and removes the argument from
__lock_acquire(), the next patch will remove the now unused arg
from lock_acquire() and update its callers.
Signed-off-by: Oleg Nesterov <o...@redhat.com>
---
include/linux/lockdep.h | 1 -
kernel/locking/lockdep.c | 22 ++++++++--------------
2 files changed, 8 insertions(+), 15 deletions(-)
diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
index 92b1bfc..13bd13d 100644
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h
@@ -252,7 +252,6 @@ struct held_lock {
unsigned int trylock:1; /* 16
bits */
unsigned int read:2; /* see lock_acquire() comment */
- unsigned int check:2; /* see lock_acquire() comment */
unsigned int hardirqs_off:1;
unsigned int references:11; /* 32
bits */
};
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index 576ba75..32ba948 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -2096,7 +2096,8 @@ static int validate_chain(struct task_struct *curr,
struct lockdep_map *lock,
* (If lookup_chain_cache() returns with 1 it acquires
* graph_lock for us)
*/
- if (!hlock->trylock && (hlock->check == 2) &&
+ if (!hlock->trylock && prove_locking &&
+ hlock_class(hlock)->key != __lockdep_no_validate__.subkeys &&
lookup_chain_cache(curr, hlock, chain_key)) {
/*
* Check whether last held lock:
@@ -3041,7 +3042,7 @@ static int __lock_is_held(struct lockdep_map *lock);
* We maintain the dependency maps and validate the locking attempt:
*/
static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
- int trylock, int read, int check, int hardirqs_off,
+ int trylock, int read, int hardirqs_off,
struct lockdep_map *nest_lock, unsigned long ip,
int references)
{
@@ -3053,9 +3054,6 @@ static int __lock_acquire(struct lockdep_map *lock,
unsigned int subclass,
int class_idx;
u64 chain_key;
- if (!prove_locking)
- check = 1;
-
if (unlikely(!debug_locks))
return 0;
@@ -3067,9 +3065,6 @@ static int __lock_acquire(struct lockdep_map *lock,
unsigned int subclass,
if (DEBUG_LOCKS_WARN_ON(!irqs_disabled()))
return 0;
- if (lock->key == &__lockdep_no_validate__)
- check = 1;
-
if (subclass < NR_LOCKDEP_CACHING_CLASSES)
class = lock->class_cache[subclass];
/*
@@ -3128,7 +3123,6 @@ static int __lock_acquire(struct lockdep_map *lock,
unsigned int subclass,
hlock->nest_lock = nest_lock;
hlock->trylock = trylock;
hlock->read = read;
- hlock->check = check;
hlock->hardirqs_off = !!hardirqs_off;
hlock->references = references;
#ifdef CONFIG_LOCK_STAT
@@ -3136,7 +3130,7 @@ static int __lock_acquire(struct lockdep_map *lock,
unsigned int subclass,
hlock->holdtime_stamp = lockstat_clock();
#endif
- if (check == 2 && !mark_irqflags(curr, hlock))
+ if (prove_locking && !mark_irqflags(curr, hlock))
return 0;
/* mark it as used: */
@@ -3338,7 +3332,7 @@ found_it:
hlock = curr->held_locks + i;
if (!__lock_acquire(hlock->instance,
hlock_class(hlock)->subclass, hlock->trylock,
- hlock->read, hlock->check, hlock->hardirqs_off,
+ hlock->read, hlock->hardirqs_off,
hlock->nest_lock, hlock->acquire_ip,
hlock->references))
return 0;
@@ -3422,7 +3416,7 @@ found_it:
hlock = curr->held_locks + i;
if (!__lock_acquire(hlock->instance,
hlock_class(hlock)->subclass, hlock->trylock,
- hlock->read, hlock->check, hlock->hardirqs_off,
+ hlock->read, hlock->hardirqs_off,
hlock->nest_lock, hlock->acquire_ip,
hlock->references))
return 0;
@@ -3598,8 +3592,8 @@ void lock_acquire(struct lockdep_map *lock, unsigned int
subclass,
current->lockdep_recursion = 1;
trace_lock_acquire(lock, subclass, trylock, read, check, nest_lock, ip);
- __lock_acquire(lock, subclass, trylock, read, check,
- irqs_disabled_flags(flags), nest_lock, ip, 0);
+ __lock_acquire(lock, subclass, trylock, read,
+ irqs_disabled_flags(flags), nest_lock, ip, 0);
current->lockdep_recursion = 0;
raw_local_irq_restore(flags);
}
--
1.5.5.1
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
