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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, frederic@kernel.org,
	tglx@linutronix.de, boqun.feng@gmail.com,
	linux-kernel@vger.kernel.org, Yuyang Du <duyuyang@gmail.com>
Subject: [PATCH 13/17] locking/lockdep: Add nest lock type
Date: Mon, 13 May 2019 17:11:59 +0800	[thread overview]
Message-ID: <20190513091203.7299-14-duyuyang@gmail.com> (raw)
In-Reply-To: <20190513091203.7299-1-duyuyang@gmail.com>

Add a macro LOCK_TYPE_NEST for nest lock type and mark the nested lock in
check_deadlock_current(). Unlike the other LOCK_TYPE_* enums, this lock type
is used only in lockdep.

No functional change.

Signed-off-by: Yuyang Du <duyuyang@gmail.com>
---
 kernel/locking/lockdep.c           | 7 +++++--
 kernel/locking/lockdep_internals.h | 1 +
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index c94c105..417b23d 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -2523,6 +2523,7 @@ static inline void inc_chains(void)
  *  0: on deadlock detected;
  *  1: on OK;
  *  2: LOCK_TYPE_RECURSIVE on recursive read
+ *  3: LOCK_TYPE_NEST on nest lock
  */
 static int
 check_deadlock_current(struct task_struct *curr, struct held_lock *next)
@@ -2552,7 +2553,7 @@ static inline void inc_chains(void)
 		 * nesting behaviour.
 		 */
 		if (nest)
-			return LOCK_TYPE_RECURSIVE;
+			return LOCK_TYPE_NEST;
 
 		print_deadlock_bug(curr, prev, next);
 		return 0;
@@ -3127,11 +3128,13 @@ static int validate_chain(struct task_struct *curr,
 
 		if (!ret)
 			return 0;
+
 		/*
 		 * Add dependency only if this lock is not the head
 		 * of the chain, and if it's not a secondary read-lock:
 		 */
-		if (!chain_head && ret != LOCK_TYPE_RECURSIVE) {
+		if (!chain_head && ret != LOCK_TYPE_RECURSIVE &&
+		    ret != LOCK_TYPE_NEST) {
 			if (!check_prevs_add(curr, hlock))
 				return 0;
 		}
diff --git a/kernel/locking/lockdep_internals.h b/kernel/locking/lockdep_internals.h
index c287bcb..b06c405 100644
--- a/kernel/locking/lockdep_internals.h
+++ b/kernel/locking/lockdep_internals.h
@@ -28,6 +28,7 @@ enum lock_usage_bit {
 
 #define LOCK_TYPE_BITS	16
 #define LOCK_TYPE_MASK	0xFFFF
+#define LOCK_TYPE_NEST	3
 
 /*
  * Usage-state bitmasks:
-- 
1.8.3.1


  parent reply	other threads:[~2019-05-13  9:14 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-05-13  9:11 [PATCH 00/17] Support for read-write lock deadlock detection Yuyang Du
2019-05-13  9:11 ` [PATCH 01/17] locking/lockdep: Add lock type enum to explicitly specify read or write locks Yuyang Du
2019-05-13 11:45   ` Peter Zijlstra
2019-05-14  1:31     ` Yuyang Du
2019-05-14 12:04       ` Peter Zijlstra
2019-05-13  9:11 ` [PATCH 02/17] locking/lockdep: Add read-write type for dependency Yuyang Du
2019-05-13  9:11 ` [PATCH 03/17] locking/lockdep: Add helper functions to operate on the searched path Yuyang Du
2019-05-13  9:11 ` [PATCH 04/17] locking/lockdep: Update direct dependency's read-write type if it exists Yuyang Du
2019-05-13  9:11 ` [PATCH 05/17] locking/lockdep: Rename deadlock check functions Yuyang Du
2019-05-13  9:11 ` [PATCH 06/17] locking/lockdep: Adjust BFS algorithm to support multiple matches Yuyang Du
2019-05-13  9:11 ` [PATCH 07/17] locking/lockdep: Introduce mark_lock_unaccessed() Yuyang Du
2019-05-13  9:11 ` [PATCH 08/17] locking/lockdep: Introduce chain_hlocks_type for held lock's read-write type Yuyang Du
2019-05-13  9:11 ` [PATCH 09/17] locking/lockdep: Hash held lock's read-write type into chain key Yuyang Du
2019-05-13  9:11 ` [PATCH 10/17] locking/lockdep: Support read-write lock's deadlock detection Yuyang Du
2019-05-13  9:11 ` [PATCH 11/17] locking/lockdep: Adjust lockdep selftest cases Yuyang Du
2019-05-13  9:11 ` [PATCH 12/17] locking/lockdep: Remove useless lock type assignment Yuyang Du
2019-05-13  9:11 ` Yuyang Du [this message]
2019-05-13  9:12 ` [PATCH 14/17] locking/lockdep: Support recursive read locks Yuyang Du
2019-05-13  9:12 ` [PATCH 15/17] locking/lockdep: Adjust selftest case for recursive read lock Yuyang Du
2019-05-13  9:12 ` [PATCH 16/17] locking/lockdep: Add more lockdep selftest cases Yuyang Du
2019-05-13  9:12 ` [PATCH 17/17] locking/lockdep: Remove irq-safe to irq-unsafe read check Yuyang Du
2019-05-13  9:17 ` [PATCH 00/17] Support for read-write lock deadlock detection Yuyang Du

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