redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

x86/intel_rdt/cqm: Add rmdir support 

Resource groups (ctrl_mon and monitor groups) are represented by
directories in resctrl fs. Add support to remove the directories.

When a ctrl_mon directory is removed all the cpus and tasks are assigned
back to the root rdtgroup. When a monitor group is removed the cpus and
tasks are returned to the parent control group.

Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-22-git-send-email-vikas.shivappa@linux.intel.com
hifive-unleashed-5.1
Vikas Shivappa 2017-07-25 14:14:40 -07:00 committed by Thomas Gleixner
parent f9049547f7
commit f3cbeacaa0
1 changed files with 86 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

90
arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
View File

@ -1130,6 +1130,18 @@ static int reset_all_ctrls(struct rdt_resource *r)
return 0;
}
static bool is_closid_match(struct task_struct *t, struct rdtgroup *r)
{
return (rdt_alloc_capable &&
(r->type == RDTCTRL_GROUP) && (t->closid == r->closid));
}
static bool is_rmid_match(struct task_struct *t, struct rdtgroup *r)
{
return (rdt_mon_capable &&
(r->type == RDTMON_GROUP) && (t->rmid == r->mon.rmid));
}
/*
* Move tasks from one to the other group. If @from is NULL, then all tasks
* in the systems are moved unconditionally (used for teardown).
@ -1145,8 +1157,11 @@ static void rdt_move_group_tasks(struct rdtgroup *from, struct rdtgroup *to,
read_lock(&tasklist_lock);
for_each_process_thread(p, t) {
if (!from || t->closid == from->closid) {
if (!from || is_closid_match(t, from) ||
is_rmid_match(t, from)) {
t->closid = to->closid;
t->rmid = to->mon.rmid;
#ifdef CONFIG_SMP
/*
* This is safe on x86 w/o barriers as the ordering
@ -1165,6 +1180,19 @@ static void rdt_move_group_tasks(struct rdtgroup *from, struct rdtgroup *to,
read_unlock(&tasklist_lock);
}
static void free_all_child_rdtgrp(struct rdtgroup *rdtgrp)
{
struct rdtgroup *sentry, *stmp;
struct list_head *head;
head = &rdtgrp->mon.crdtgrp_list;
list_for_each_entry_safe(sentry, stmp, head, mon.crdtgrp_list) {
free_rmid(sentry->mon.rmid);
list_del(&sentry->mon.crdtgrp_list);
kfree(sentry);
}
}
/*
* Forcibly remove all of subdirectories under root.
*/
@ -1565,6 +1593,44 @@ static int rdtgroup_mkdir(struct kernfs_node *parent_kn, const char *name,
return -EPERM;
}
static int rdtgroup_rmdir_mon(struct kernfs_node *kn, struct rdtgroup *rdtgrp,
cpumask_var_t tmpmask)
{
struct rdtgroup *prdtgrp = rdtgrp->mon.parent;
int cpu;
/* Give any tasks back to the parent group */
rdt_move_group_tasks(rdtgrp, prdtgrp, tmpmask);
/* Update per cpu rmid of the moved CPUs first */
for_each_cpu(cpu, &rdtgrp->cpu_mask)
per_cpu(rdt_cpu_default.rmid, cpu) = prdtgrp->mon.rmid;
/*
* Update the MSR on moved CPUs and CPUs which have moved
* task running on them.
*/
cpumask_or(tmpmask, tmpmask, &rdtgrp->cpu_mask);
update_closid_rmid(tmpmask, NULL);
rdtgrp->flags = RDT_DELETED;
free_rmid(rdtgrp->mon.rmid);
/*
* Remove the rdtgrp from the parent ctrl_mon group's list
*/
WARN_ON(list_empty(&prdtgrp->mon.crdtgrp_list));
list_del(&rdtgrp->mon.crdtgrp_list);
/*
* one extra hold on this, will drop when we kfree(rdtgrp)
* in rdtgroup_kn_unlock()
*/
kernfs_get(kn);
kernfs_remove(rdtgrp->kn);
return 0;
}
static int rdtgroup_rmdir_ctrl(struct kernfs_node *kn, struct rdtgroup *rdtgrp,
cpumask_var_t tmpmask)
{
@ -1577,9 +1643,12 @@ static int rdtgroup_rmdir_ctrl(struct kernfs_node *kn, struct rdtgroup *rdtgrp,
cpumask_or(&rdtgroup_default.cpu_mask,
&rdtgroup_default.cpu_mask, &rdtgrp->cpu_mask);
/* Update per cpu closid of the moved CPUs first */
for_each_cpu(cpu, &rdtgrp->cpu_mask)
/* Update per cpu closid and rmid of the moved CPUs first */
for_each_cpu(cpu, &rdtgrp->cpu_mask) {
per_cpu(rdt_cpu_default.closid, cpu) = rdtgroup_default.closid;
per_cpu(rdt_cpu_default.rmid, cpu) = rdtgroup_default.mon.rmid;
}
/*
* Update the MSR on moved CPUs and CPUs which have moved
* task running on them.
@ -1589,6 +1658,13 @@ static int rdtgroup_rmdir_ctrl(struct kernfs_node *kn, struct rdtgroup *rdtgrp,
rdtgrp->flags = RDT_DELETED;
closid_free(rdtgrp->closid);
free_rmid(rdtgrp->mon.rmid);
/*
* Free all the child monitor group rmids.
*/
free_all_child_rdtgrp(rdtgrp);
list_del(&rdtgrp->rdtgroup_list);
/*
@ -1619,10 +1695,16 @@ static int rdtgroup_rmdir(struct kernfs_node *kn)
/*
* If the rdtgroup is a ctrl_mon group and parent directory
* is the root directory, remove the ctrl group.
* is the root directory, remove the ctrl_mon group.
*
* If the rdtgroup is a mon group and parent directory
* is a valid "mon_groups" directory, remove the mon group.
*/
if (rdtgrp->type == RDTCTRL_GROUP && parent_kn == rdtgroup_default.kn)
ret = rdtgroup_rmdir_ctrl(kn, rdtgrp, tmpmask);
else if (rdtgrp->type == RDTMON_GROUP &&
is_mon_groups(parent_kn, kn->name))
ret = rdtgroup_rmdir_mon(kn, rdtgrp, tmpmask);
else
ret = -EPERM;