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, Yuyang Du <duyuyang@gmail.com>
Subject: [PATCH v2 19/19] locking/lockdep: Change if to else-if when checking bfs errors
Date: Mon, 18 Mar 2019 16:57:33 +0800 [thread overview]
Message-ID: <20190318085733.3143-20-duyuyang@gmail.com> (raw)
In-Reply-To: <20190318085733.3143-1-duyuyang@gmail.com>
After BFS searching, we check whether there is an error. These checks are
exclusive, so we can use "else if" instead of "if", which results in a bit
optimized code.
No functional change.
Signed-off-by: Yuyang Du <duyuyang@gmail.com>
---
kernel/locking/lockdep.c | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index 1d38bf6..3efc00e 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -1950,21 +1950,21 @@ static void print_lock_class_header(struct lock_class *class, int depth)
this.class = hlock_class(prev);
ret = find_usage_backwards(&this, bit_backwards, &target_entry);
- if (ret < 0) {
+ if (unlikely(ret < 0)) {
print_bfs_bug(ret);
return 0;
}
- if (ret == 1)
+ else if (ret == 1)
return ret;
that.parent = NULL;
that.class = hlock_class(next);
ret = find_usage_forwards(&that, bit_forwards, &target_entry1);
- if (ret < 0) {
+ if (unlikely(ret < 0)) {
print_bfs_bug(ret);
return 0;
}
- if (ret == 1)
+ else if (ret == 1)
return ret;
print_bad_irq_dependency(curr, &this, &that,
@@ -2282,7 +2282,7 @@ static void print_deadlock_scenario(struct held_lock *nxt,
debug_atomic_inc(nr_redundant);
return 2;
}
- if (ret < 0) {
+ else if (unlikely(ret < 0)) {
print_bfs_bug(ret);
return 0;
}
@@ -2967,11 +2967,11 @@ static int mark_lock(struct task_struct *curr, struct held_lock *this,
root.parent = NULL;
root.class = hlock_class(this);
ret = find_usage_forwards(&root, bit, &target_entry);
- if (ret < 0) {
+ if (unlikely(ret < 0)) {
print_bfs_bug(ret);
return 0;
}
- if (ret == 1)
+ else if (ret == 1)
return ret;
print_irq_inversion_bug(curr, &root, target_entry,
@@ -2994,11 +2994,11 @@ static int mark_lock(struct task_struct *curr, struct held_lock *this,
root.parent = NULL;
root.class = hlock_class(this);
ret = find_usage_backwards(&root, bit, &target_entry);
- if (ret < 0) {
+ if (unlikely(ret < 0)) {
print_bfs_bug(ret);
return 0;
}
- if (ret == 1)
+ else if (ret == 1)
return ret;
print_irq_inversion_bug(curr, &root, target_entry,
--
1.8.3.1
next prev parent reply other threads:[~2019-03-18 8:58 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-18 8:57 [PATCH v2 00/19] locking/lockdep: Add comments and make some code Yuyang Du
2019-03-18 8:57 ` [PATCH v2 01/19] locking/lockdep: Change all print_*() return type to void Yuyang Du
2019-03-18 9:45 ` Joe Perches
2019-03-19 3:28 ` Yuyang Du
2019-03-19 16:30 ` Bart Van Assche
2019-03-18 8:57 ` [PATCH v2 02/19] locking/lockdep: Add description and explanation in lockdep design doc Yuyang Du
2019-03-18 8:57 ` [PATCH v2 03/19] locking/lockdep: Adjust lock usage bit character checks Yuyang Du
2019-03-18 8:57 ` [PATCH v2 04/19] locking/lockdep: Remove useless conditional macro Yuyang Du
2019-03-18 8:57 ` [PATCH v2 05/19] locking/lockdep: Adjust indents for function definitions Yuyang Du
2019-03-19 16:33 ` Bart Van Assche
2019-03-19 16:36 ` Peter Zijlstra
2019-03-18 8:57 ` [PATCH v2 06/19] locking/lockdep: Print the right depth for chain key colission Yuyang Du
2019-03-18 8:57 ` [PATCH v2 07/19] locking/lockdep: Update obsolete struct field description Yuyang Du
2019-03-19 16:35 ` Bart Van Assche
2019-03-19 16:44 ` Peter Zijlstra
2019-03-18 8:57 ` [PATCH v2 08/19] locking/lockdep: Use lockdep_init_task for task initiation consistently Yuyang Du
2019-03-18 8:57 ` [PATCH v2 09/19] locking/lockdep: Define INITIAL_CHAIN_KEY for chain keys to start with Yuyang Du
2019-03-18 8:57 ` [PATCH v2 10/19] locking/lockdep: Change the range of class_idx in held_lock struct Yuyang Du
2019-03-18 8:57 ` [PATCH v2 11/19] locking/lockdep: Remove unused argument in validate_chain() Yuyang Du
2019-03-19 16:45 ` Bart Van Assche
2019-03-18 8:57 ` [PATCH v2 12/19] locking/lockdep: Update comment Yuyang Du
2019-03-18 8:57 ` [PATCH v2 13/19] locking/lockdep: Remove unnecessary function pointer argument Yuyang Du
2019-03-19 16:48 ` Bart Van Assche
2019-03-18 8:57 ` [PATCH v2 14/19] locking/lockdep: Change type of the element field in circular_queue Yuyang Du
2019-03-19 16:50 ` Bart Van Assche
2019-03-19 16:51 ` Bart Van Assche
2019-03-18 8:57 ` [PATCH v2 15/19] locking/lockdep: Remove __cq_empty() Yuyang Du
2019-03-19 16:54 ` Bart Van Assche
2019-03-20 2:30 ` Yuyang Du
2019-03-18 8:57 ` [PATCH v2 16/19] locking/lockdep: Use function pointer to avoid constant checks Yuyang Du
2019-03-19 16:56 ` Bart Van Assche
2019-03-18 8:57 ` [PATCH v2 17/19] locking/lockdep: Combine check_noncircular and check_redundant Yuyang Du
2019-03-18 8:57 ` [PATCH v2 18/19] locking/lockdep: Update comments on dependency search Yuyang Du
2019-03-18 8:57 ` Yuyang Du [this message]
2019-03-19 16:29 ` [PATCH v2 19/19] locking/lockdep: Change if to else-if when checking bfs errors Bart Van Assche
2019-03-19 17:19 ` Joe Perches
2019-03-20 2:02 ` Yuyang Du
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