[tip:x86/cache] x86/intel_rdt: Ensure RDT cleanup on exit

[tip-bot for Reinette Chatre <tipbot@zytor.com>]

Commit-ID:  0af6a48da481109affc4ea8295034f69993a91ef
Gitweb:     https://git.kernel.org/tip/0af6a48da481109affc4ea8295034f69993a91ef
Author:     Reinette Chatre <reinette.chatre@intel.com>
AuthorDate: Fri, 22 Jun 2018 15:42:24 -0700
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Sat, 23 Jun 2018 13:03:50 +0200

x86/intel_rdt: Ensure RDT cleanup on exit

The RDT system's initialization does not have the corresponding exit
handling to ensure everything initialized on load is cleaned up also.

Introduce the cleanup routines that complement all initialization. This
includes the removal of a duplicate rdtgroup_init() declaration.

Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: fenghua.yu@intel.com
Cc: tony.luck@intel.com
Cc: vikas.shivappa@linux.intel.com
Cc: gavin.hindman@intel.com
Cc: jithu.joseph@intel.com
Cc: dave.hansen@intel.com
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/a9e3a2bbd731d13915d2d7bf05d4f675b4fa109b.1529706536.git.reinette.chatre@intel.com

---
 arch/x86/kernel/cpu/intel_rdt.c          | 11 +++++++++++
 arch/x86/kernel/cpu/intel_rdt.h          |  3 +--
 arch/x86/kernel/cpu/intel_rdt_rdtgroup.c |  7 +++++++
 3 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/cpu/intel_rdt.c b/arch/x86/kernel/cpu/intel_rdt.c
index ec4754f81cbd..abb71ac70443 100644
--- a/arch/x86/kernel/cpu/intel_rdt.c
+++ b/arch/x86/kernel/cpu/intel_rdt.c
@@ -859,6 +859,8 @@ static __init bool get_rdt_resources(void)
 	return (rdt_mon_capable || rdt_alloc_capable);
 }
 
+static enum cpuhp_state rdt_online;
+
 static int __init intel_rdt_late_init(void)
 {
 	struct rdt_resource *r;
@@ -880,6 +882,7 @@ static int __init intel_rdt_late_init(void)
 		cpuhp_remove_state(state);
 		return ret;
 	}
+	rdt_online = state;
 
 	for_each_alloc_capable_rdt_resource(r)
 		pr_info("Intel RDT %s allocation detected\n", r->name);
@@ -891,3 +894,11 @@ static int __init intel_rdt_late_init(void)
 }
 
 late_initcall(intel_rdt_late_init);
+
+static void __exit intel_rdt_exit(void)
+{
+	cpuhp_remove_state(rdt_online);
+	rdtgroup_exit();
+}
+
+__exitcall(intel_rdt_exit);
diff --git a/arch/x86/kernel/cpu/intel_rdt.h b/arch/x86/kernel/cpu/intel_rdt.h
index f245aaae514e..2b3f7619be48 100644
--- a/arch/x86/kernel/cpu/intel_rdt.h
+++ b/arch/x86/kernel/cpu/intel_rdt.h
@@ -209,6 +209,7 @@ extern struct list_head rdt_all_groups;
 extern int max_name_width, max_data_width;
 
 int __init rdtgroup_init(void);
+void __exit rdtgroup_exit(void);
 
 /**
  * struct rftype - describe each file in the resctrl file system
@@ -431,8 +432,6 @@ extern struct rdt_resource rdt_resources_all[];
 extern struct rdtgroup rdtgroup_default;
 DECLARE_STATIC_KEY_FALSE(rdt_alloc_enable_key);
 
-int __init rdtgroup_init(void);
-
 enum {
 	RDT_RESOURCE_L3,
 	RDT_RESOURCE_L3DATA,
diff --git a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
index f301919ae9b2..960066249374 100644
--- a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
+++ b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
@@ -2828,3 +2828,10 @@ cleanup_root:
 
 	return ret;
 }
+
+void __exit rdtgroup_exit(void)
+{
+	unregister_filesystem(&rdt_fs_type);
+	sysfs_remove_mount_point(fs_kobj, "resctrl");
+	kernfs_destroy_root(rdt_root);
+}