From: Ingo Molnar <mingo@kernel.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org,
Peter Zijlstra <a.p.zijlstra@chello.nl>,
Thomas Gleixner <tglx@linutronix.de>,
"Paul E. McKenney" <paulmck@us.ibm.com>,
Andrew Morton <akpm@linux-foundation.org>
Subject: [GIT PULL] locking fixes
Date: Thu, 28 Apr 2016 19:52:43 +0200 [thread overview]
Message-ID: <20160428175243.GA10211@gmail.com> (raw)
Linus,
Please pull the latest locking-urgent-for-linus git tree from:
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git locking-urgent-for-linus
# HEAD: 75dd602a5198a6e5f75534db52b6e6fbaabb33d1 lockdep: Fix lock_chain::base size
Two lockdep fixes.
Thanks,
Ingo
------------------>
Boqun Feng (1):
locking/lockdep: Fix ->irq_context calculation
Peter Zijlstra (1):
lockdep: Fix lock_chain::base size
include/linux/lockdep.h | 8 +++++---
kernel/locking/lockdep.c | 37 ++++++++++++++++++++++++++++++++++---
kernel/locking/lockdep_proc.c | 2 ++
3 files changed, 41 insertions(+), 6 deletions(-)
diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
index d026b190c530..d10ef06971b5 100644
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h
@@ -196,9 +196,11 @@ struct lock_list {
* We record lock dependency chains, so that we can cache them:
*/
struct lock_chain {
- u8 irq_context;
- u8 depth;
- u16 base;
+ /* see BUILD_BUG_ON()s in lookup_chain_cache() */
+ unsigned int irq_context : 2,
+ depth : 6,
+ base : 24;
+ /* 4 byte hole */
struct hlist_node entry;
u64 chain_key;
};
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index ed9410936a22..78c1c0ee6dc1 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -2176,15 +2176,37 @@ static inline int lookup_chain_cache(struct task_struct *curr,
chain->irq_context = hlock->irq_context;
i = get_first_held_lock(curr, hlock);
chain->depth = curr->lockdep_depth + 1 - i;
+
+ BUILD_BUG_ON((1UL << 24) <= ARRAY_SIZE(chain_hlocks));
+ BUILD_BUG_ON((1UL << 6) <= ARRAY_SIZE(curr->held_locks));
+ BUILD_BUG_ON((1UL << 8*sizeof(chain_hlocks[0])) <= ARRAY_SIZE(lock_classes));
+
if (likely(nr_chain_hlocks + chain->depth <= MAX_LOCKDEP_CHAIN_HLOCKS)) {
chain->base = nr_chain_hlocks;
- nr_chain_hlocks += chain->depth;
for (j = 0; j < chain->depth - 1; j++, i++) {
int lock_id = curr->held_locks[i].class_idx - 1;
chain_hlocks[chain->base + j] = lock_id;
}
chain_hlocks[chain->base + j] = class - lock_classes;
}
+
+ if (nr_chain_hlocks < MAX_LOCKDEP_CHAIN_HLOCKS)
+ nr_chain_hlocks += chain->depth;
+
+#ifdef CONFIG_DEBUG_LOCKDEP
+ /*
+ * Important for check_no_collision().
+ */
+ if (unlikely(nr_chain_hlocks > MAX_LOCKDEP_CHAIN_HLOCKS)) {
+ if (debug_locks_off_graph_unlock())
+ return 0;
+
+ print_lockdep_off("BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low!");
+ dump_stack();
+ return 0;
+ }
+#endif
+
hlist_add_head_rcu(&chain->entry, hash_head);
debug_atomic_inc(chain_lookup_misses);
inc_chains();
@@ -2932,6 +2954,11 @@ static int mark_irqflags(struct task_struct *curr, struct held_lock *hlock)
return 1;
}
+static inline unsigned int task_irq_context(struct task_struct *task)
+{
+ return 2 * !!task->hardirq_context + !!task->softirq_context;
+}
+
static int separate_irq_context(struct task_struct *curr,
struct held_lock *hlock)
{
@@ -2940,8 +2967,6 @@ static int separate_irq_context(struct task_struct *curr,
/*
* Keep track of points where we cross into an interrupt context:
*/
- hlock->irq_context = 2*(curr->hardirq_context ? 1 : 0) +
- curr->softirq_context;
if (depth) {
struct held_lock *prev_hlock;
@@ -2973,6 +2998,11 @@ static inline int mark_irqflags(struct task_struct *curr,
return 1;
}
+static inline unsigned int task_irq_context(struct task_struct *task)
+{
+ return 0;
+}
+
static inline int separate_irq_context(struct task_struct *curr,
struct held_lock *hlock)
{
@@ -3241,6 +3271,7 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
hlock->acquire_ip = ip;
hlock->instance = lock;
hlock->nest_lock = nest_lock;
+ hlock->irq_context = task_irq_context(curr);
hlock->trylock = trylock;
hlock->read = read;
hlock->check = check;
diff --git a/kernel/locking/lockdep_proc.c b/kernel/locking/lockdep_proc.c
index dbb61a302548..a0f61effad25 100644
--- a/kernel/locking/lockdep_proc.c
+++ b/kernel/locking/lockdep_proc.c
@@ -141,6 +141,8 @@ static int lc_show(struct seq_file *m, void *v)
int i;
if (v == SEQ_START_TOKEN) {
+ if (nr_chain_hlocks > MAX_LOCKDEP_CHAIN_HLOCKS)
+ seq_printf(m, "(buggered) ");
seq_printf(m, "all lock chains:\n");
return 0;
}
next reply other threads:[~2016-04-28 17:52 UTC|newest]
Thread overview: 62+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-04-28 17:52 Ingo Molnar [this message]
-- strict thread matches above, loose matches on Subject: below --
2023-09-22 10:12 [GIT PULL] locking fixes Ingo Molnar
2023-09-22 20:19 ` pr-tracker-bot
2021-07-11 13:22 Ingo Molnar
2021-07-11 18:22 ` pr-tracker-bot
2021-04-11 12:14 Ingo Molnar
2021-04-11 18:56 ` pr-tracker-bot
2021-03-21 10:53 Ingo Molnar
2021-03-21 18:45 ` pr-tracker-bot
2020-12-27 9:50 Ingo Molnar
2020-12-27 17:27 ` pr-tracker-bot
2020-08-15 11:13 Ingo Molnar
2020-08-16 1:55 ` pr-tracker-bot
2020-01-18 17:53 Ingo Molnar
2020-01-18 21:05 ` pr-tracker-bot
2019-12-17 11:27 Ingo Molnar
2019-12-17 19:20 ` pr-tracker-bot
2019-04-20 7:30 Ingo Molnar
2019-04-20 16:51 ` Linus Torvalds
2019-04-21 18:23 ` Ingo Molnar
2019-04-20 19:25 ` pr-tracker-bot
2019-02-10 8:53 Ingo Molnar
2019-02-10 18:30 ` pr-tracker-bot
2018-10-05 9:36 Ingo Molnar
2018-10-05 23:06 ` Greg Kroah-Hartman
2018-09-15 12:56 Ingo Molnar
2018-07-30 17:49 Ingo Molnar
2018-03-25 8:49 Ingo Molnar
2018-02-15 0:50 Ingo Molnar
2018-01-17 15:24 Ingo Molnar
2018-01-22 9:43 ` Geert Uytterhoeven
2018-01-22 10:39 ` Peter Zijlstra
2018-01-12 13:45 Ingo Molnar
2017-12-15 15:55 Ingo Molnar
2017-10-14 16:01 Ingo Molnar
2017-03-07 20:27 Ingo Molnar
2017-02-28 7:57 Ingo Molnar
2017-02-28 18:37 ` Linus Torvalds
2017-05-03 23:21 ` Linus Torvalds
2017-05-04 5:40 ` Peter Zijlstra
[not found] ` <CA+55aFymvtCAYHdz__3Lj=YqmORB7_A-NXrw=+h+60znJVsDTw@mail.gmail.com>
2017-05-04 22:44 ` Greg Kroah-Hartman
2016-12-07 18:42 Ingo Molnar
2016-10-18 10:55 Ingo Molnar
2016-08-18 20:34 Ingo Molnar
2016-08-12 19:32 Ingo Molnar
2016-06-10 12:45 Ingo Molnar
2016-04-23 11:22 Ingo Molnar
2016-03-24 7:47 Ingo Molnar
2015-09-17 7:57 Ingo Molnar
2015-04-18 15:15 Ingo Molnar
2015-02-20 13:37 Ingo Molnar
2015-02-21 0:03 ` Linus Torvalds
2015-02-21 1:51 ` Linus Torvalds
2015-02-23 8:35 ` Christian Borntraeger
2015-02-21 5:07 ` Ingo Molnar
2015-02-21 5:16 ` Ingo Molnar
2015-02-21 5:28 ` Ingo Molnar
2015-01-11 8:39 Ingo Molnar
2014-10-31 11:06 Ingo Molnar
2014-04-16 11:39 Ingo Molnar
2014-01-15 18:15 Ingo Molnar
2009-12-10 19:45 Ingo Molnar
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