Add monitoring support during mount and unmount. Since root directory is
a "ctrl_mon" directory which can control and monitor resources create
the "mon_groups" directory which can hold monitor groups and a
"mon_data" directory which would hold all monitoring data like the rest
of resource groups.
The mount succeeds if either of monitoring or control/allocation is
enabled. If only monitoring is enabled user can still create monitor
groups under the "/sys/fs/resctrl/mon_groups/" and any mkdir under root
would fail. If only control/allocation is enabled all of the monitoring
related directories/files would not exist and resctrl would work in
legacy mode.
Signed-off-by: Vikas Shivappa <vikas.shiva...@linux.intel.com>
---
arch/x86/kernel/cpu/intel_rdt.h | 5 +++
arch/x86/kernel/cpu/intel_rdt_monitor.c | 3 ++
arch/x86/kernel/cpu/intel_rdt_rdtgroup.c | 67 +++++++++++++++++++++++++++++---
3 files changed, 70 insertions(+), 5 deletions(-)
diff --git a/arch/x86/kernel/cpu/intel_rdt.h b/arch/x86/kernel/cpu/intel_rdt.h
index 631d58e..ea7a86f 100644
--- a/arch/x86/kernel/cpu/intel_rdt.h
+++ b/arch/x86/kernel/cpu/intel_rdt.h
@@ -22,6 +22,9 @@
#define RMID_VAL_ERROR (1ULL << 63)
#define RMID_VAL_UNAVAIL (1ULL << 62)
+
+DECLARE_STATIC_KEY_FALSE(rdt_enable_key);
+
/**
* struct mon_evt - Entry in the event list of a resource
* @evtid: event id
@@ -59,6 +62,8 @@ struct rmid_read {
extern int rdt_mon_features;
DECLARE_PER_CPU_READ_MOSTLY(int, cpu_rmid);
+DECLARE_STATIC_KEY_FALSE(rdt_mon_enable_key);
+
enum rdt_group_type {
RDTCTRL_GROUP = 0,
diff --git a/arch/x86/kernel/cpu/intel_rdt_monitor.c
b/arch/x86/kernel/cpu/intel_rdt_monitor.c
index cc252eb..a7247ca 100644
--- a/arch/x86/kernel/cpu/intel_rdt_monitor.c
+++ b/arch/x86/kernel/cpu/intel_rdt_monitor.c
@@ -76,6 +76,9 @@ struct rmid_entry {
unsigned int intel_cqm_threshold;
DEFINE_PER_CPU_READ_MOSTLY(int, cpu_rmid);
+
+DEFINE_STATIC_KEY_FALSE(rdt_mon_enable_key);
+
static inline struct rmid_entry *__rmid_entry(u32 rmid)
{
struct rmid_entry *entry;
diff --git a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
index 6131508..2384c07 100644
--- a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
+++ b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
@@ -35,6 +35,7 @@
#include <asm/intel_rdt_sched.h>
#include "intel_rdt.h"
+DEFINE_STATIC_KEY_FALSE(rdt_enable_key);
DEFINE_STATIC_KEY_FALSE(rdt_alloc_enable_key);
struct kernfs_root *rdt_root;
struct rdtgroup rdtgroup_default;
@@ -43,6 +44,12 @@
/* Kernel fs node for "info" directory under root */
static struct kernfs_node *kn_info;
+/* Kernel fs node for "mon_groups" directory under root */
+static struct kernfs_node *kn_mongrp;
+
+/* Kernel fs node for "mon_data" directory under root */
+static struct kernfs_node *kn_mondata;
+
/*
* Trivial allocator for CLOSIDs. Since h/w only supports a small number,
* we can keep a bitmap of free CLOSIDs in a single integer.
@@ -1078,6 +1085,9 @@ void rdtgroup_kn_unlock(struct kernfs_node *kn)
}
}
+static int mkdir_mondata_all(struct kernfs_node *parent_kn, struct rdtgroup
*pr,
+ struct kernfs_node **mon_data_kn);
+
static struct dentry *rdt_mount(struct file_system_type *fs_type,
int flags, const char *unused_dev_name,
void *data)
@@ -1089,7 +1099,7 @@ static struct dentry *rdt_mount(struct file_system_type
*fs_type,
/*
* resctrl file system can only be mounted once.
*/
- if (static_branch_unlikely(&rdt_alloc_enable_key)) {
+ if (static_branch_unlikely(&rdt_enable_key)) {
dentry = ERR_PTR(-EBUSY);
goto out;
}
@@ -1108,15 +1118,47 @@ static struct dentry *rdt_mount(struct file_system_type
*fs_type,
goto out_cdp;
}
+ if (rdt_mon_features) {
+ ret = mongroup_create_dir(rdtgroup_default.kn,
+ NULL, "mon_groups",
+ &kn_mongrp);
+ if (ret) {
+ dentry = ERR_PTR(ret);
+ goto out_info;
+ }
+ kernfs_get(kn_mongrp);
+
+ ret = mkdir_mondata_all(rdtgroup_default.kn,
+ &rdtgroup_default, &kn_mondata);
+ if (ret) {
+ dentry = ERR_PTR(ret);
+ goto out_mongrp;
+ }
+ kernfs_get(kn_mondata);
+ rdtgroup_default.mon_data_kn = kn_mondata;
+ }
+
dentry = kernfs_mount(fs_type, flags, rdt_root,
RDTGROUP_SUPER_MAGIC, NULL);
if (IS_ERR(dentry))
- goto out_destroy;
+ goto out_mondata;
- static_branch_enable(&rdt_alloc_enable_key);
+ if (rdt_alloc_enabled)
+ static_branch_enable(&rdt_alloc_enable_key);
+ if (rdt_mon_features)
+ static_branch_enable(&rdt_mon_enable_key);
+
+ if (rdt_alloc_enabled || rdt_mon_features)
+ static_branch_enable(&rdt_enable_key);
goto out;
-out_destroy:
+out_mondata:
+ if (rdt_mon_features)
+ kernfs_remove(kn_mondata);
+out_mongrp:
+ if (rdt_mon_features)
+ kernfs_remove(kn_mongrp);
+out_info:
kernfs_remove(kn_info);
out_cdp:
cdp_disable();
@@ -1219,12 +1261,21 @@ static void rdt_move_group_tasks(struct rdtgroup *from,
struct rdtgroup *to,
*/
static void rmdir_all_sub(void)
{
- struct rdtgroup *rdtgrp, *tmp;
+ struct rdtgroup *rdtgrp, *tmp, *sentry, *stmp;
+ struct list_head *llist;
/* Move all tasks to the default resource group */
rdt_move_group_tasks(NULL, &rdtgroup_default, NULL);
list_for_each_entry_safe(rdtgrp, tmp, &rdt_all_groups, rdtgroup_list) {
+ /* Free any child rmids */
+ llist = &rdtgrp->crdtgrp_list;
+ list_for_each_entry_safe(sentry, stmp, llist, crdtgrp_list) {
+ free_rmid(sentry->rmid);
+ list_del(&sentry->crdtgrp_list);
+ kfree(sentry);
+ }
+
/* Remove each rdtgroup other than root */
if (rdtgrp == &rdtgroup_default)
continue;
@@ -1237,6 +1288,8 @@ static void rmdir_all_sub(void)
cpumask_or(&rdtgroup_default.cpu_mask,
&rdtgroup_default.cpu_mask, &rdtgrp->cpu_mask);
+ free_rmid(rdtgrp->rmid);
+
kernfs_remove(rdtgrp->kn);
list_del(&rdtgrp->rdtgroup_list);
kfree(rdtgrp);
@@ -1247,6 +1300,8 @@ static void rmdir_all_sub(void)
put_online_cpus();
kernfs_remove(kn_info);
+ kernfs_remove(kn_mongrp);
+ kernfs_remove(kn_mondata);
}
static void rdt_kill_sb(struct super_block *sb)
@@ -1261,6 +1316,8 @@ static void rdt_kill_sb(struct super_block *sb)
cdp_disable();
rmdir_all_sub();
static_branch_disable(&rdt_alloc_enable_key);
+ static_branch_disable(&rdt_mon_enable_key);
+ static_branch_disable(&rdt_enable_key);
kernfs_kill_sb(sb);
mutex_unlock(&rdtgroup_mutex);
}
--
1.9.1
