| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <tip-d8d88fbb186fe3ea37b2a58adb32413c98b59656@git.kernel.org>
Date: Tue, 22 Sep 2009 08:41:14 GMT
From: tip-bot for Darren Hart <dvhltc@...ibm.com>
To: linux-tip-commits@...r.kernel.org
Cc: linux-kernel@...r.kernel.org, dvhltc@...ibm.com, hpa@...or.com,
mingo@...hat.com, eric.dumazet@...il.com, johnstul@...ibm.com,
peterz@...radead.org, dino@...ibm.com, rostedt@...dmis.org,
tglx@...utronix.de, mingo@...e.hu
Subject: [tip:core/urgent] futex: Correct futex_q woken state commentary
Commit-ID: d8d88fbb186fe3ea37b2a58adb32413c98b59656
Gitweb: http://git.kernel.org/tip/d8d88fbb186fe3ea37b2a58adb32413c98b59656
Author: Darren Hart <dvhltc@...ibm.com>
AuthorDate: Mon, 21 Sep 2009 22:30:30 -0700
Committer: Ingo Molnar <mingo@...e.hu>
CommitDate: Tue, 22 Sep 2009 10:37:44 +0200
futex: Correct futex_q woken state commentary
Use kernel-doc format to describe struct futex_q.
Correct the wakeup definition to eliminate the statement about
waking the waiter between the plist_del() and the q->lock_ptr = 0.
Note in the comment that PI futexes have a different definition of
the woken state.
Signed-off-by: Darren Hart <dvhltc@...ibm.com>
Acked-by: Peter Zijlstra <peterz@...radead.org>
Cc: Steven Rostedt <rostedt@...dmis.org>
Cc: Eric Dumazet <eric.dumazet@...il.com>
Cc: Dinakar Guniguntala <dino@...ibm.com>
Cc: John Stultz <johnstul@...ibm.com>
LKML-Reference: <20090922053029.8717.62798.stgit@...n>
Signed-off-by: Ingo Molnar <mingo@...e.hu>
---
kernel/futex.c | 32 ++++++++++++++++----------------
1 files changed, 16 insertions(+), 16 deletions(-)
diff --git a/kernel/futex.c b/kernel/futex.c
index 720fa3d..f92afbe 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -89,36 +89,36 @@ struct futex_pi_state {
union futex_key key;
};
-/*
- * We use this hashed waitqueue instead of a normal wait_queue_t, so
+/**
+ * struct futex_q - The hashed futex queue entry, one per waiting task
+ * @task: the task waiting on the futex
+ * @lock_ptr: the hash bucket lock
+ * @key: the key the futex is hashed on
+ * @pi_state: optional priority inheritance state
+ * @rt_waiter: rt_waiter storage for use with requeue_pi
+ * @requeue_pi_key: the requeue_pi target futex key
+ * @bitset: bitset for the optional bitmasked wakeup
+ *
+ * We use this hashed waitqueue, instead of a normal wait_queue_t, so
* we can wake only the relevant ones (hashed queues may be shared).
*
* A futex_q has a woken state, just like tasks have TASK_RUNNING.
* It is considered woken when plist_node_empty(&q->list) || q->lock_ptr == 0.
* The order of wakup is always to make the first condition true, then
- * wake up q->waiter, then make the second condition true.
+ * the second.
+ *
+ * PI futexes are typically woken before they are removed from the hash list via
+ * the rt_mutex code. See unqueue_me_pi().
*/
struct futex_q {
struct plist_node list;
- /* Waiter reference */
- struct task_struct *task;
- /* Which hash list lock to use: */
+ struct task_struct *task;
spinlock_t *lock_ptr;
-
- /* Key which the futex is hashed on: */
union futex_key key;
-
- /* Optional priority inheritance state: */
struct futex_pi_state *pi_state;
-
- /* rt_waiter storage for requeue_pi: */
struct rt_mutex_waiter *rt_waiter;
-
- /* The expected requeue pi target futex key: */
union futex_key *requeue_pi_key;
-
- /* Bitset for the optional bitmasked wakeup */
u32 bitset;
};
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists