From: Peter Rosin <peda@axentia.se>
To: linux-kernel@vger.kernel.org
Cc: Peter Rosin <peda@axentia.se>, Wolfram Sang <wsa@the-dreams.de>,
Peter Zijlstra <peterz@infradead.org>,
Ingo Molnar <mingo@redhat.com>, Will Deacon <will.deacon@arm.com>,
Davidlohr Bueso <dave@stgolabs.net>,
Philippe Ombredanne <pombredanne@nexb.com>,
Thomas Gleixner <tglx@linutronix.de>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
linux-i2c@vger.kernel.org, Peter Chang <dpf@google.com>,
Deepa Dinamani <deepadinamani@google.com>,
John Sperbeck <jsperbeck@google.com>
Subject: [PATCH v4 1/2] rtmutex: allow specifying a subclass for nested locking
Date: Fri, 20 Jul 2018 10:39:13 +0200 [thread overview]
Message-ID: <20180720083914.1950-2-peda@axentia.se> (raw)
In-Reply-To: <20180720083914.1950-1-peda@axentia.se>
Needed for annotating rt_mutex locks.
Tested-by: John Sperbeck <jsperbeck@google.com>
Signed-off-by: Peter Rosin <peda@axentia.se>
---
include/linux/rtmutex.h | 7 +++++++
kernel/locking/rtmutex.c | 29 +++++++++++++++++++++++++----
2 files changed, 32 insertions(+), 4 deletions(-)
diff --git a/include/linux/rtmutex.h b/include/linux/rtmutex.h
index 1b92a28dd672..6fd615a0eea9 100644
--- a/include/linux/rtmutex.h
+++ b/include/linux/rtmutex.h
@@ -106,7 +106,14 @@ static inline int rt_mutex_is_locked(struct rt_mutex *lock)
extern void __rt_mutex_init(struct rt_mutex *lock, const char *name, struct lock_class_key *key);
extern void rt_mutex_destroy(struct rt_mutex *lock);
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+extern void rt_mutex_lock_nested(struct rt_mutex *lock, unsigned int subclass);
+#define rt_mutex_lock(lock) rt_mutex_lock_nested(lock, 0)
+#else
extern void rt_mutex_lock(struct rt_mutex *lock);
+#define rt_mutex_lock_nested(lock, subclass) rt_mutex_lock(lock)
+#endif
+
extern int rt_mutex_lock_interruptible(struct rt_mutex *lock);
extern int rt_mutex_timed_lock(struct rt_mutex *lock,
struct hrtimer_sleeper *timeout);
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index 4f014be7a4b8..2823d4163a37 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -1465,6 +1465,29 @@ rt_mutex_fastunlock(struct rt_mutex *lock,
rt_mutex_postunlock(&wake_q);
}
+static inline void __rt_mutex_lock(struct rt_mutex *lock, unsigned int subclass)
+{
+ might_sleep();
+
+ mutex_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
+ rt_mutex_fastlock(lock, TASK_UNINTERRUPTIBLE, rt_mutex_slowlock);
+}
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+/**
+ * rt_mutex_lock_nested - lock a rt_mutex
+ *
+ * @lock: the rt_mutex to be locked
+ * @subclass: the lockdep subclass
+ */
+void __sched rt_mutex_lock_nested(struct rt_mutex *lock, unsigned int subclass)
+{
+ __rt_mutex_lock(lock, subclass);
+}
+EXPORT_SYMBOL_GPL(rt_mutex_lock_nested);
+#endif
+
+#ifndef CONFIG_DEBUG_LOCK_ALLOC
/**
* rt_mutex_lock - lock a rt_mutex
*
@@ -1472,12 +1495,10 @@ rt_mutex_fastunlock(struct rt_mutex *lock,
*/
void __sched rt_mutex_lock(struct rt_mutex *lock)
{
- might_sleep();
-
- mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_);
- rt_mutex_fastlock(lock, TASK_UNINTERRUPTIBLE, rt_mutex_slowlock);
+ __rt_mutex_lock(lock, 0);
}
EXPORT_SYMBOL_GPL(rt_mutex_lock);
+#endif
/**
* rt_mutex_lock_interruptible - lock a rt_mutex interruptible
--
2.11.0
next prev parent reply other threads:[~2018-07-20 8:39 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-07-20 8:39 [PATCH v4 0/2] Fix lockdep warning with nested instances of i2c-mux Peter Rosin
2018-07-20 8:39 ` Peter Rosin [this message]
2018-09-10 23:27 ` [PATCH v4 1/2] rtmutex: allow specifying a subclass for nested locking Steven Rostedt
2018-09-11 0:58 ` Peter Rosin
2018-07-20 8:39 ` [PATCH v4 2/2] i2c: mux: annotate the nested rt_mutex usage Peter Rosin
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20180720083914.1950-2-peda@axentia.se \
--to=peda@axentia.se \
--cc=dave@stgolabs.net \
--cc=deepadinamani@google.com \
--cc=dpf@google.com \
--cc=gregkh@linuxfoundation.org \
--cc=jsperbeck@google.com \
--cc=linux-i2c@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=peterz@infradead.org \
--cc=pombredanne@nexb.com \
--cc=tglx@linutronix.de \
--cc=will.deacon@arm.com \
--cc=wsa@the-dreams.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).