locking/rwsem: Provide down_write_killable()
Now that all the architectures implement the necessary glue code
we can introduce down_write_killable(). The only difference wrt. regular
down_write() is that the slow path waits in TASK_KILLABLE state and the
interruption by the fatal signal is reported as -EINTR to the caller.
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Signed-off-by: Jason Low <jason.low2@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-alpha@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: linux-xtensa@linux-xtensa.org
Cc: sparclinux@vger.kernel.org
Link: http://lkml.kernel.org/r/1460041951-22347-12-git-send-email-mhocko@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
index d026b19..accfe56 100644
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h
@@ -444,6 +444,18 @@
lock_acquired(&(_lock)->dep_map, _RET_IP_); \
} while (0)
+#define LOCK_CONTENDED_RETURN(_lock, try, lock) \
+({ \
+ int ____err = 0; \
+ if (!try(_lock)) { \
+ lock_contended(&(_lock)->dep_map, _RET_IP_); \
+ ____err = lock(_lock); \
+ } \
+ if (!____err) \
+ lock_acquired(&(_lock)->dep_map, _RET_IP_); \
+ ____err; \
+})
+
#else /* CONFIG_LOCK_STAT */
#define lock_contended(lockdep_map, ip) do {} while (0)
@@ -452,6 +464,9 @@
#define LOCK_CONTENDED(_lock, try, lock) \
lock(_lock)
+#define LOCK_CONTENDED_RETURN(_lock, try, lock) \
+ lock(_lock)
+
#endif /* CONFIG_LOCK_STAT */
#ifdef CONFIG_LOCKDEP
diff --git a/include/linux/rwsem.h b/include/linux/rwsem.h
index 7d7ae02..d1c12d1 100644
--- a/include/linux/rwsem.h
+++ b/include/linux/rwsem.h
@@ -118,6 +118,7 @@
* lock for writing
*/
extern void down_write(struct rw_semaphore *sem);
+extern int __must_check down_write_killable(struct rw_semaphore *sem);
/*
* trylock for writing -- returns 1 if successful, 0 if contention