[PATCH 04/37] locking/lockdep: Convert usage_mask to u64

Frederic Weisbecker
2019-02-28T17:13:10Z

The usage mask is going to expand to validate softirq related usages in
a per-vector finegrained way.

The current bitmap layout is:

LOCK_USED HARDIRQ bits
\ /
\ /
0 0000 0000
|
|
SOFTIRQ bits

The new one will be:

TIMER_SOFTIRQ
LOCK_USED bits HARDIRQ bits
\ | |
\ | |
0 0000 [...] 0000 0000 0000
| |
| |
RCU_SOFTIRQ HI_SOFTIRQ bits
bits

So we have 4 hardirq bits + NR_SOFTIRQS * 4 + 1 bit (LOCK_USED) = 45
bits. Therefore we need a 64 bits mask.

Reviewed-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Pavan Kondeti <pkondeti@codeaurora.org>
Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com>
Cc: David S . Miller <davem@davemloft.net>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
---
include/linux/lockdep.h | 2 +-
kernel/locking/lockdep.c | 24 ++++++++++++------------
2 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
index c5335df2372f..06669f20a30a 100644
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h
@@ -83,7 +83,7 @@ struct lock_class {
/*
* IRQ/softirq usage tracking bits:
*/
- unsigned long usage_mask;
+ u64 usage_mask;
struct stack_trace usage_traces[XXX_LOCK_USAGE_STATES];

/*
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index 4fc859c0a799..004278969afc 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -463,12 +463,12 @@ const char * __get_key_name(struct lockdep_subclass_key *key, char *str)
return kallsyms_lookup((unsigned long)key, NULL, NULL, NULL, str);
}

-static inline unsigned long lock_flag(enum lock_usage_bit bit)
+static inline u64 lock_flag(enum lock_usage_bit bit)
{
- return 1UL << bit;
+ return BIT_ULL(bit);
}

-static unsigned long lock_usage_mask(struct lock_usage *usage)
+static u64 lock_usage_mask(struct lock_usage *usage)
{
return lock_flag(usage->bit);
}
@@ -1342,7 +1342,7 @@ check_redundant(struct lock_list *root, struct lock_class *target,

static inline int usage_match(struct lock_list *entry, void *mask)
{
- return entry->class->usage_mask & *(unsigned long *)mask;
+ return entry->class->usage_mask & *(u64 *)mask;
}

@@ -1358,7 +1358,7 @@ static inline int usage_match(struct lock_list *entry, void *mask)
* Return <0 on error.
*/
static int
-find_usage_forwards(struct lock_list *root, unsigned long usage_mask,
+find_usage_forwards(struct lock_list *root, u64 usage_mask,
struct lock_list **target_entry)
{
int result;
@@ -1381,7 +1381,7 @@ find_usage_forwards(struct lock_list *root, unsigned long usage_mask,
* Return <0 on error.
*/
static int
-find_usage_backwards(struct lock_list *root, unsigned long usage_mask,
+find_usage_backwards(struct lock_list *root, u64 usage_mask,
struct lock_list **target_entry)
{
int result;
@@ -1405,7 +1405,7 @@ static void print_lock_class_header(struct lock_class *class, int depth)
printk(KERN_CONT " {\n");

for (bit = 0; bit < LOCK_USAGE_STATES; bit++) {
- if (class->usage_mask & (1 << bit)) {
+ if (class->usage_mask & lock_flag(bit)) {
int len = depth;

len += printk("%*s %s", depth, "", usage_str[bit]);
@@ -2484,7 +2484,7 @@ static inline int
valid_state(struct task_struct *curr, struct held_lock *this,
enum lock_usage_bit new_bit, enum lock_usage_bit bad_bit)
{
- if (unlikely(hlock_class(this)->usage_mask & (1 << bad_bit)))
+ if (unlikely(hlock_class(this)->usage_mask & lock_flag(bad_bit)))
return print_usage_bug(curr, this, bad_bit, new_bit);
return 1;
}
@@ -2559,7 +2559,7 @@ print_irq_inversion_bug(struct task_struct *curr,
*/
static int
check_usage_forwards(struct task_struct *curr, struct held_lock *this,
- unsigned long usage_mask, const char *irqclass)
+ u64 usage_mask, const char *irqclass)
{
int ret;
struct lock_list root;
@@ -2583,7 +2583,7 @@ check_usage_forwards(struct task_struct *curr, struct held_lock *this,
*/
static int
check_usage_backwards(struct task_struct *curr, struct held_lock *this,
- unsigned long usage_mask, const char *irqclass)
+ u64 usage_mask, const char *irqclass)
{
int ret;
struct lock_list root;
@@ -2650,7 +2650,7 @@ static inline int state_verbose(enum lock_usage_bit bit,
}

typedef int (*check_usage_f)(struct task_struct *, struct held_lock *,
- unsigned long usage_mask, const char *name);
+ u64 usage_mask, const char *name);

static int
mark_lock_irq(struct task_struct *curr, struct held_lock *this,
@@ -3034,7 +3034,7 @@ static inline int separate_irq_context(struct task_struct *curr,
static int mark_lock(struct task_struct *curr, struct held_lock *this,
struct lock_usage *new_usage)
{
- unsigned long new_mask = lock_usage_mask(new_usage), ret = 1;
+ u64 new_mask = lock_usage_mask(new_usage), ret = 1;

/*
* If already set then do not dirty the cacheline,
--
2.21.0