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authorYuyang Du2019-05-06 10:19:24 +0200
committerIngo Molnar2019-06-03 11:55:43 +0200
commitf6ec8829ac9d59b637366c13038f15d6f6156fe1 (patch)
tree66564bff3b185212908d1c4c164d0304af2d9f12 /kernel/locking
parentlocking/lockdep: Use lockdep_init_task for task initiation consistently (diff)
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locking/lockdep: Define INITIAL_CHAIN_KEY for chain keys to start with
Chain keys are computed using Jenkins hash function, which needs an initial hash to start with. Dedicate a macro to make this clear and configurable. A later patch changes this initial chain key. Signed-off-by: Yuyang Du <duyuyang@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-9-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/locking')
-rw-r--r--kernel/locking/lockdep.c18
1 files changed, 9 insertions, 9 deletions
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index b7d9c28ecf3b..9edf6f12b711 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -362,7 +362,7 @@ static inline u64 iterate_chain_key(u64 key, u32 idx)
void lockdep_init_task(struct task_struct *task)
{
task->lockdep_depth = 0; /* no locks held yet */
- task->curr_chain_key = 0;
+ task->curr_chain_key = INITIAL_CHAIN_KEY;
task->lockdep_recursion = 0;
}
@@ -857,7 +857,7 @@ static u16 chain_hlocks[MAX_LOCKDEP_CHAIN_HLOCKS];
static bool check_lock_chain_key(struct lock_chain *chain)
{
#ifdef CONFIG_PROVE_LOCKING
- u64 chain_key = 0;
+ u64 chain_key = INITIAL_CHAIN_KEY;
int i;
for (i = chain->base; i < chain->base + chain->depth; i++)
@@ -2524,7 +2524,7 @@ static void
print_chain_keys_held_locks(struct task_struct *curr, struct held_lock *hlock_next)
{
struct held_lock *hlock;
- u64 chain_key = 0;
+ u64 chain_key = INITIAL_CHAIN_KEY;
int depth = curr->lockdep_depth;
int i = get_first_held_lock(curr, hlock_next);
@@ -2544,7 +2544,7 @@ print_chain_keys_held_locks(struct task_struct *curr, struct held_lock *hlock_ne
static void print_chain_keys_chain(struct lock_chain *chain)
{
int i;
- u64 chain_key = 0;
+ u64 chain_key = INITIAL_CHAIN_KEY;
int class_id;
printk("depth: %u\n", chain->depth);
@@ -2848,7 +2848,7 @@ static void check_chain_key(struct task_struct *curr)
#ifdef CONFIG_DEBUG_LOCKDEP
struct held_lock *hlock, *prev_hlock = NULL;
unsigned int i;
- u64 chain_key = 0;
+ u64 chain_key = INITIAL_CHAIN_KEY;
for (i = 0; i < curr->lockdep_depth; i++) {
hlock = curr->held_locks + i;
@@ -2872,7 +2872,7 @@ static void check_chain_key(struct task_struct *curr)
if (prev_hlock && (prev_hlock->irq_context !=
hlock->irq_context))
- chain_key = 0;
+ chain_key = INITIAL_CHAIN_KEY;
chain_key = iterate_chain_key(chain_key, hlock->class_idx);
prev_hlock = hlock;
}
@@ -3787,14 +3787,14 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
/*
* How can we have a chain hash when we ain't got no keys?!
*/
- if (DEBUG_LOCKS_WARN_ON(chain_key != 0))
+ if (DEBUG_LOCKS_WARN_ON(chain_key != INITIAL_CHAIN_KEY))
return 0;
chain_head = 1;
}
hlock->prev_chain_key = chain_key;
if (separate_irq_context(curr, hlock)) {
- chain_key = 0;
+ chain_key = INITIAL_CHAIN_KEY;
chain_head = 1;
}
chain_key = iterate_chain_key(chain_key, class_idx);
@@ -4636,7 +4636,7 @@ static void remove_class_from_lock_chain(struct pending_free *pf,
return;
recalc:
- chain_key = 0;
+ chain_key = INITIAL_CHAIN_KEY;
for (i = chain->base; i < chain->base + chain->depth; i++)
chain_key = iterate_chain_key(chain_key, chain_hlocks[i] + 1);
if (chain->depth && chain->chain_key == chain_key)