[PATCH v2 08/17] locking/lockdep: Introduce chain_hlocks_type for held lock's read-write type

Yuyang Du
2019-05-16T08:00:56Z

Lock chain needs to include information about the read-write lock type. To
that end, introduce:

chain_hlocks_type[MAX_LOCKDEP_CHAIN_HLOCKS]

in addition to:

chain_hlocks[MAX_LOCKDEP_CHAIN_HLOCKS]

Signed-off-by: Yuyang Du <duyuyang@gmail.com>
---
kernel/locking/lockdep.c | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index 617c0f4..f11d018d 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -861,6 +861,7 @@ static bool class_lock_list_valid(struct lock_class *c, struct list_head *h)

#ifdef CONFIG_PROVE_LOCKING
static u16 chain_hlocks[MAX_LOCKDEP_CHAIN_HLOCKS];
+static u16 chain_hlocks_type[MAX_LOCKDEP_CHAIN_HLOCKS];
#endif

static bool check_lock_chain_key(struct lock_chain *chain)
@@ -2668,6 +2669,7 @@ static inline void inc_chains(void)
static DECLARE_BITMAP(lock_chains_in_use, MAX_LOCKDEP_CHAINS);
int nr_chain_hlocks;
static u16 chain_hlocks[MAX_LOCKDEP_CHAIN_HLOCKS];
+static u16 chain_hlocks_type[MAX_LOCKDEP_CHAIN_HLOCKS];

struct lock_class *lock_chain_get_class(struct lock_chain *chain, int i)
{
@@ -2872,9 +2874,12 @@ static inline int add_chain_cache(struct task_struct *curr,
chain->base = nr_chain_hlocks;
for (j = 0; j < chain->depth - 1; j++, i++) {
int lock_id = curr->held_locks[i].class_idx;
+ int lock_type = curr->held_locks[i].read;
chain_hlocks[chain->base + j] = lock_id;
+ chain_hlocks_type[chain->base + j] = lock_type;
}
chain_hlocks[chain->base + j] = class - lock_classes;
+ chain_hlocks_type[chain->base + j] = hlock->read;
nr_chain_hlocks += chain->depth;
} else {
if (!debug_locks_off_graph_unlock())
@@ -4824,6 +4829,9 @@ static void remove_class_from_lock_chain(struct pending_free *pf,
memmove(&chain_hlocks[i], &chain_hlocks[i + 1],
(chain->base + chain->depth - i) *
sizeof(chain_hlocks[0]));
+ memmove(&chain_hlocks_type[i], &chain_hlocks_type[i + 1],
+ (chain->base + chain->depth - i) *
+ sizeof(chain_hlocks_type[0]));
}
/*
* Each lock class occurs at most once in a lock chain so once
@@ -5268,6 +5276,7 @@ void __init lockdep_init(void)
+ sizeof(lock_chains)
+ sizeof(lock_chains_in_use)
+ sizeof(chain_hlocks)
+ + sizeof(chain_hlocks_type)
#endif
) / 1024
);
--
1.8.3.1