x86/intel_rdt: Fix incorrect returned value when creating rdgroup sub-directory in...

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

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

  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 <[email protected]>
Signed-off-by: Zhang Yanfei <[email protected]>
Signed-off-by: Fenghua Yu <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ravi V Shankar <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Tony Luck <[email protected]>
Cc: Vikas <[email protected]>
Cc: Xiaochen Shen <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

diff --git a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
index bdab7d2f51af4c2a32d18d891f54b5bc60f60bd4..fca759d272a1783e76d86dfa38e213d167f39ade 100644 (file)
--- 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);