[tip: x86/cache] x86/resctrl: Use container_of() in delayed_work handlers

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     f995801ba3a0660cb352c8beb794379c82781ca3
Gitweb:        https://git.kernel.org/tip/f995801ba3a0660cb352c8beb794379c82781ca3
Author:        James Morse <james.morse@xxxxxxx>
AuthorDate:    Wed, 08 Jul 2020 16:39:23 
Committer:     Borislav Petkov <bp@xxxxxxx>
CommitterDate: Tue, 18 Aug 2020 17:05:08 +02:00

x86/resctrl: Use container_of() in delayed_work handlers

mbm_handle_overflow() and cqm_handle_limbo() are both provided with
the domain's work_struct when called, but use get_domain_from_cpu()
to find the domain, along with the appropriate error handling.

container_of() saves some list walking and bitmap testing, use that
instead.

Signed-off-by: James Morse <james.morse@xxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Reviewed-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>
Link: https://lkml.kernel.org/r/20200708163929.2783-5-james.morse@xxxxxxx
---
 arch/x86/kernel/cpu/resctrl/monitor.c | 13 ++-----------
 1 file changed, 2 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index d6b92d7..54dffe5 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -477,19 +477,13 @@ void cqm_handle_limbo(struct work_struct *work)
 	mutex_lock(&rdtgroup_mutex);
 
 	r = &rdt_resources_all[RDT_RESOURCE_L3];
-	d = get_domain_from_cpu(cpu, r);
-
-	if (!d) {
-		pr_warn_once("Failure to get domain for limbo worker\n");
-		goto out_unlock;
-	}
+	d = container_of(work, struct rdt_domain, cqm_limbo.work);
 
 	__check_limbo(d, false);
 
 	if (has_busy_rmid(r, d))
 		schedule_delayed_work_on(cpu, &d->cqm_limbo, delay);
 
-out_unlock:
 	mutex_unlock(&rdtgroup_mutex);
 }
 
@@ -519,10 +513,7 @@ void mbm_handle_overflow(struct work_struct *work)
 		goto out_unlock;
 
 	r = &rdt_resources_all[RDT_RESOURCE_L3];
-
-	d = get_domain_from_cpu(cpu, r);
-	if (!d)
-		goto out_unlock;
+	d = container_of(work, struct rdt_domain, mbm_over.work);
 
 	list_for_each_entry(prgrp, &rdt_all_groups, rdtgroup_list) {
 		mbm_update(r, d, prgrp->mon.rmid);