From: Tejun Heo <tj@kernel.org>
Date: Wed, 28 Aug 2019 15:05:52 -0700
Subject: [PATCH] blkcg: make ->cpd_init_fn() optional
References: bsc#1156419,jsc#SLE-8281
Git-commit: 86a5bba5c252e90d264c7460e29a0b9e633777e7
Patch-mainline: v5.4-rc1

For policies which can do enough initialization from ->cpd_alloc_fn(),
make ->cpd_init_fn() optional.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Hannes Reinecke <hare@suse.de>
---
 block/blk-cgroup.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 6a82ca3fb5cf..78ccbdcfe723 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -1475,7 +1475,8 @@ int blkcg_policy_register(struct blkcg_policy *pol)
 			blkcg->cpd[pol->plid] = cpd;
 			cpd->blkcg = blkcg;
 			cpd->plid = pol->plid;
-			pol->cpd_init_fn(cpd);
+			if (pol->cpd_init_fn)
+				pol->cpd_init_fn(cpd);
 		}
 	}
 
-- 
2.16.4