diff options
Diffstat (limited to 'include/linux/lockdep.h')
| -rw-r--r-- | include/linux/lockdep.h | 22 |
1 files changed, 21 insertions, 1 deletions
diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h index c75eedd55af5..651cc61af041 100644 --- a/include/linux/lockdep.h +++ b/include/linux/lockdep.h @@ -325,6 +325,19 @@ struct hist_lock { */ struct cross_lock { /* + * When more than one acquisition of crosslocks are overlapped, + * we have to perform commit for them based on cross_gen_id of + * the first acquisition, which allows us to add more true + * dependencies. + * + * Moreover, when no acquisition of a crosslock is in progress, + * we should not perform commit because the lock might not exist + * any more, which might cause incorrect memory access. So we + * have to track the number of acquisitions of a crosslock. + */ + int nr_acquire; + + /* * Seperate hlock instance. This will be used at commit step. * * TODO: Use a smaller data structure containing only necessary @@ -547,9 +560,16 @@ extern void lockdep_init_map_crosslock(struct lockdep_map *lock, int subclass); extern void lock_commit_crosslock(struct lockdep_map *lock); +/* + * What we essencially have to initialize is 'nr_acquire'. Other members + * will be initialized in add_xlock(). + */ +#define STATIC_CROSS_LOCK_INIT() \ + { .nr_acquire = 0,} + #define STATIC_CROSS_LOCKDEP_MAP_INIT(_name, _key) \ { .map.name = (_name), .map.key = (void *)(_key), \ - .map.cross = 1, } + .map.cross = 1, .xlock = STATIC_CROSS_LOCK_INIT(), } /* * To initialize a lockdep_map statically use this macro. |