[PATCH 3/3] driver/core: Fix build error when SRCU and lockdep disabled

From: "Joel Fernandes (Google)" <joel@joelfernandes.org>
To: linux-kernel@vger.kernel.org
Cc: "Joel Fernandes (Google)" <joel@joelfernandes.org>,
	kbuild test robot <lkp@intel.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Jonathan Corbet <corbet@lwn.net>,
	Josh Triplett <josh@joshtriplett.org>,
	Lai Jiangshan <jiangshanlai@gmail.com>,
	linux-doc@vger.kernel.org,
	Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
	"Paul E. McKenney" <paulmck@linux.ibm.com>,
	"Rafael J. Wysocki" <rafael@kernel.org>,
	rcu@vger.kernel.org, Steven Rostedt <rostedt@goodmis.org>,
	Tejun Heo <tj@kernel.org>
Subject: [PATCH 3/3] driver/core: Fix build error when SRCU and lockdep disabled
Date: Sun, 11 Aug 2019 18:11:11 -0400	[thread overview]
Message-ID: <20190811221111.99401-3-joel@joelfernandes.org> (raw)
In-Reply-To: <20190811221111.99401-1-joel@joelfernandes.org>

Properly check if lockdep lock checking is disabled at config time. If
so, then lock_is_held() is undefined so don't do any checking.

This fix is similar to the pattern used in srcu_read_lock_held().

Link: https://lore.kernel.org/lkml/201908080026.WSAFx14k%25lkp@intel.com/
Fixes: c9e4d3a2fee8 ("acpi: Use built-in RCU list checking for acpi_ioremaps list")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
---
This patch is based on the -rcu dev branch.

 drivers/base/core.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 32cf83d1c744..fe25cf690562 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -99,7 +99,11 @@ void device_links_read_unlock(int not_used)
 
 int device_links_read_lock_held(void)
 {
-	return lock_is_held(&device_links_lock);
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+	return lock_is_held(&(device_links_lock.dep_map));
+#else
+	return 1;
+#endif
 }
 #endif /* !CONFIG_SRCU */
 
-- 
2.23.0.rc1.153.gdeed80330f-goog
