[PATCH v4 06/30] locking/lockdep: Update comments in struct lock_list and held_lock

From: Yuyang Du
Date: Thu Aug 29 2019 - 04:32:12 EST


The comments regarding initial chain key and BFS are outdated, so update them.

Signed-off-by: Yuyang Du <duyuyang@xxxxxxxxx>
---
include/linux/lockdep.h | 17 ++++++++---------
1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
index d7bec61..0246a70 100644
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h
@@ -195,8 +195,7 @@ struct lock_list {
int distance;

/*
- * The parent field is used to implement breadth-first search, and the
- * bit 0 is reused to indicate if the lock has been accessed in BFS.
+ * The parent field is used to implement breadth-first search.
*/
struct lock_list *parent;
};
@@ -239,7 +238,7 @@ struct held_lock {
* as likely as possible - hence the 64-bit width.
*
* The task struct holds the current hash value (initialized
- * with zero), here we store the previous hash value:
+ * with INITIAL_CHAIN_KEY), here we store the previous hash value:
*/
u64 prev_chain_key;
unsigned long acquire_ip;
@@ -258,12 +257,12 @@ struct held_lock {
/*
* The lock-stack is unified in that the lock chains of interrupt
* contexts nest ontop of process context chains, but we 'separate'
- * the hashes by starting with 0 if we cross into an interrupt
- * context, and we also keep do not add cross-context lock
- * dependencies - the lock usage graph walking covers that area
- * anyway, and we'd just unnecessarily increase the number of
- * dependencies otherwise. [Note: hardirq and softirq contexts
- * are separated from each other too.]
+ * the hashes by starting with a new chain if we cross into an
+ * interrupt context, and we also keep not adding cross-context
+ * lock dependencies - the lock usage graph walking covers that
+ * area anyway, and we'd just unnecessarily increase the number
+ * of dependencies otherwise. [Note: hardirq and softirq
+ * contexts are separated from each other too.]
*
* The following field is used to detect when we cross into an
* interrupt context:
--
1.8.3.1