linux-yocto-rt/5.4: fix 5.4-stable caused build breakage
5.4-stable included a backport of:
Author: Eric W. Biederman <ebiederm@xmission.com>
Date: Thu Dec 3 14:11:13 2020 -0600
rwsem: Implement down_read_interruptible
[ Upstream commit
31784cff7ee073b34d6eddabb95e3be2880a425c ]
In preparation for converting exec_update_mutex to a rwsem so that
multiple readers can execute in parallel and not deadlock, add
down_read_interruptible. This is needed for perf_event_open to be
converted (with no semantic changes) from working on a mutex to
wroking on a rwsem.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/87k0tybqfy.fsf@x220.int.ebiederm.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
We implement a -rt variant to fix the build issues.
Signed-off-by: Bruce Ashfield <bruce.ashfield@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
