[PATCH] x86/intel_rdt: Fix incorrect returned value when creating rdgroup sub-directory in resctrl file system

["Fenghua Yu" <fenghua.yu@intel.com>]

From: Wang Hui <john.wanghui@huawei.com>

If no monitoring feature is detected because all monitoring features are
disabled during boot time or there is no monitoring feature in hardware,
creating rdtgroup sub-directory by "mkdir" command reports error:

#mkdir /sys/fs/resctrl/p1
mkdir: cannot create directory ‘/sys/fs/resctrl/p1’: No such file or
directory

But the sub-directory actually is generated and content is correct:

#ls /sys/fs/resctrl/p1
cpus  cpus_list  schemata  tasks

The error is because rdtgroup_mkdir_ctrl_mon() returns non zero value after
the sub-directory is created and the returned value is reported as an error
to user.

Clear the returned value to report to user that the sub-directory is
actually created successfully.

Signed-off-by: Wang Hui <john.wanghui@huawei.com>
Signed-off-by: Zhang Yanfei <yanfei.zhang@huawei.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
---
 arch/x86/kernel/cpu/intel_rdt_rdtgroup.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
index bdab7d2f51af..fca759d272a1 100644
--- a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
+++ b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
@@ -1804,6 +1804,7 @@ static int rdtgroup_mkdir_ctrl_mon(struct kernfs_node *parent_kn,
 		goto out_common_fail;
 	}
 	closid = ret;
+	ret = 0;
 
 	rdtgrp->closid = closid;
 	list_add(&rdtgrp->rdtgroup_list, &rdt_all_groups);
-- 
2.5.0