diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/locking-selftest.c | 2 | ||||
| -rw-r--r-- | lib/refcount.c | 18 |
2 files changed, 15 insertions, 5 deletions
diff --git a/lib/locking-selftest.c b/lib/locking-selftest.c index 1e1bbf171eca..a1705545e6ac 100644 --- a/lib/locking-selftest.c +++ b/lib/locking-selftest.c @@ -1989,6 +1989,7 @@ void locking_selftest(void) init_shared_classes(); debug_locks_silent = !debug_locks_verbose; + lockdep_set_selftest_task(current); DO_TESTCASE_6R("A-A deadlock", AA); DO_TESTCASE_6R("A-B-B-A deadlock", ABBA); @@ -2097,5 +2098,6 @@ void locking_selftest(void) printk("---------------------------------\n"); debug_locks = 1; } + lockdep_set_selftest_task(NULL); debug_locks_silent = 0; } diff --git a/lib/refcount.c b/lib/refcount.c index ebcf8cd49e05..6e904af0fb3e 100644 --- a/lib/refcount.c +++ b/lib/refcount.c @@ -33,6 +33,9 @@ * Note that the allocator is responsible for ordering things between free() * and alloc(). * + * The decrements dec_and_test() and sub_and_test() also provide acquire + * ordering on success. + * */ #include <linux/mutex.h> @@ -164,8 +167,8 @@ EXPORT_SYMBOL(refcount_inc_checked); * at UINT_MAX. * * Provides release memory ordering, such that prior loads and stores are done - * before, and provides a control dependency such that free() must come after. - * See the comment on top. + * before, and provides an acquire ordering on success such that free() + * must come after. * * Use of this function is not recommended for the normal reference counting * use case in which references are taken and released one at a time. In these @@ -190,7 +193,12 @@ bool refcount_sub_and_test_checked(unsigned int i, refcount_t *r) } while (!atomic_try_cmpxchg_release(&r->refs, &val, new)); - return !new; + if (!new) { + smp_acquire__after_ctrl_dep(); + return true; + } + return false; + } EXPORT_SYMBOL(refcount_sub_and_test_checked); @@ -202,8 +210,8 @@ EXPORT_SYMBOL(refcount_sub_and_test_checked); * decrement when saturated at UINT_MAX. * * Provides release memory ordering, such that prior loads and stores are done - * before, and provides a control dependency such that free() must come after. - * See the comment on top. + * before, and provides an acquire ordering on success such that free() + * must come after. * * Return: true if the resulting refcount is 0, false otherwise */ |