From: Yuyang Du <duyuyang@gmail.com>
To: peterz@infradead.org, will.deacon@arm.com, mingo@kernel.org
Cc: bvanassche@acm.org, ming.lei@redhat.com,
linux-kernel@vger.kernel.org, joe@perches.com,
Yuyang Du <duyuyang@gmail.com>
Subject: [PATCH v3 16/18] locking/lockdep: Combine check_noncircular and check_redundant
Date: Thu, 21 Mar 2019 15:57:23 +0800 [thread overview]
Message-ID: <20190321075725.14054-17-duyuyang@gmail.com> (raw)
In-Reply-To: <20190321075725.14054-1-duyuyang@gmail.com>
These two functions are essentially duplicates, combine them into
check_nonexistent(). Also update the comment on it.
No functional change.
Signed-off-by: Yuyang Du <duyuyang@gmail.com>
---
kernel/locking/lockdep.c | 31 +++++++++++--------------------
1 file changed, 11 insertions(+), 20 deletions(-)
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index cd6792c..8202318 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -1688,29 +1688,18 @@ unsigned long lockdep_count_backward_deps(struct lock_class *class)
}
/*
- * Prove that the dependency graph starting at <entry> can not
- * lead to <target>. Print an error and return 0 if it does.
+ * Prove that the dependency graph starting at <root> can not
+ * lead to <target>. If existent, there is a circle when adding
+ * a <target> -> <root> dependency.
+ *
+ * Print an error and return 0 if it does exist.
*/
static noinline int
-check_noncircular(struct lock_list *root, struct lock_class *target,
- struct lock_list **target_entry)
+check_nonexistent(struct lock_list *root, struct lock_class *target,
+ struct lock_list **target_entry)
{
int result;
- debug_atomic_inc(nr_cyclic_checks);
-
- result = __bfs_forwards(root, target, class_equal, target_entry);
-
- return result;
-}
-
-static noinline int
-check_redundant(struct lock_list *root, struct lock_class *target,
- struct lock_list **target_entry)
-{
- int result;
-
- debug_atomic_inc(nr_redundant_checks);
result = __bfs_forwards(root, target, class_equal, target_entry);
@@ -2246,7 +2235,8 @@ static inline void inc_chains(void)
*/
this.class = hlock_class(next);
this.parent = NULL;
- ret = check_noncircular(&this, hlock_class(prev), &target_entry);
+ debug_atomic_inc(nr_cyclic_checks);
+ ret = check_nonexistent(&this, hlock_class(prev), &target_entry);
if (unlikely(!ret)) {
if (!trace->entries) {
/*
@@ -2298,7 +2288,8 @@ static inline void inc_chains(void)
*/
this.class = hlock_class(prev);
this.parent = NULL;
- ret = check_redundant(&this, hlock_class(next), &target_entry);
+ debug_atomic_inc(nr_redundant_checks);
+ ret = check_nonexistent(&this, hlock_class(next), &target_entry);
if (!ret) {
debug_atomic_inc(nr_redundant);
return 2;
--
1.8.3.1
next prev parent reply other threads:[~2019-03-21 7:58 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-21 7:57 [PATCH v3 00/18] locking/lockdep: Add comments and make some code Yuyang Du
2019-03-21 7:57 ` [PATCH v3 01/18] locking/lockdep: Change all print_*() return type to void Yuyang Du
2019-03-21 7:57 ` [PATCH v3 02/18] locking/lockdep: Add description and explanation in lockdep design doc Yuyang Du
2019-03-21 7:57 ` [PATCH v3 03/18] locking/lockdep: Adjust lock usage bit character checks Yuyang Du
2019-03-21 7:57 ` [PATCH v3 04/18] locking/lockdep: Remove useless conditional macro Yuyang Du
2019-03-21 7:57 ` [PATCH v3 05/18] locking/lockdep: Print the right depth for chain key colission Yuyang Du
2019-03-21 7:57 ` [PATCH v3 06/18] locking/lockdep: Update obsolete struct field description Yuyang Du
2019-03-21 7:57 ` [PATCH v3 07/18] locking/lockdep: Use lockdep_init_task for task initiation consistently Yuyang Du
2019-03-21 7:57 ` [PATCH v3 08/18] locking/lockdep: Define INITIAL_CHAIN_KEY for chain keys to start with Yuyang Du
2019-03-21 7:57 ` [PATCH v3 09/18] locking/lockdep: Change the range of class_idx in held_lock struct Yuyang Du
2019-03-21 7:57 ` [PATCH v3 10/18] locking/lockdep: Remove unused argument in validate_chain() and check_deadlock() Yuyang Du
2019-03-21 7:57 ` [PATCH v3 11/18] locking/lockdep: Update comment Yuyang Du
2019-03-21 7:57 ` [PATCH v3 12/18] locking/lockdep: Remove unnecessary function pointer argument Yuyang Du
2019-03-21 7:57 ` [PATCH v3 13/18] locking/lockdep: Change type of the element field in circular_queue Yuyang Du
2019-03-21 7:57 ` [PATCH v3 14/18] locking/lockdep: Change the return type of __cq_dequeue() Yuyang Du
2019-03-21 7:57 ` [PATCH v3 15/18] locking/lockdep: Avoid constant checks in __bfs by using offset reference Yuyang Du
2019-03-21 7:57 ` Yuyang Du [this message]
2019-03-21 7:57 ` [PATCH v3 17/18] locking/lockdep: Update comments on dependency search Yuyang Du
2019-03-21 7:57 ` [PATCH v3 18/18] locking/lockdep: Add explanation to lock usage rules in lockdep design doc Yuyang Du
2019-04-04 5:03 ` Question on a lockdep test case about mixed read-write ABBA Yuyang Du
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