x86/resctrl: Preserve CDP enable over CPU hotplug

Resctrl assumes that all CPUs are online when the filesystem is mounted,
and that CPUs remember their CDP-enabled state over CPU hotplug.

This goes wrong when resctrl's CDP-enabled state changes while all the
CPUs in a domain are offline.

When a domain comes online, enable (or disable!) CDP to match resctrl's
current setting.

Fixes: 5ff193fbde ("x86/intel_rdt: Add basic resctrl filesystem support")
Suggested-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200221162105.154163-1-james.morse@arm.com
This commit is contained in:
James Morse 2020-02-21 16:21:05 +00:00 committed by Borislav Petkov
parent b0151da52a
commit 9fe0450785
3 changed files with 16 additions and 0 deletions

View File

@ -578,6 +578,8 @@ static void domain_add_cpu(int cpu, struct rdt_resource *r)
d->id = id;
cpumask_set_cpu(cpu, &d->cpu_mask);
rdt_domain_reconfigure_cdp(r);
if (r->alloc_capable && domain_setup_ctrlval(r, d)) {
kfree(d);
return;

View File

@ -601,5 +601,6 @@ bool has_busy_rmid(struct rdt_resource *r, struct rdt_domain *d);
void __check_limbo(struct rdt_domain *d, bool force_free);
bool cbm_validate_intel(char *buf, u32 *data, struct rdt_resource *r);
bool cbm_validate_amd(char *buf, u32 *data, struct rdt_resource *r);
void rdt_domain_reconfigure_cdp(struct rdt_resource *r);
#endif /* _ASM_X86_RESCTRL_INTERNAL_H */

View File

@ -1859,6 +1859,19 @@ static int set_cache_qos_cfg(int level, bool enable)
return 0;
}
/* Restore the qos cfg state when a domain comes online */
void rdt_domain_reconfigure_cdp(struct rdt_resource *r)
{
if (!r->alloc_capable)
return;
if (r == &rdt_resources_all[RDT_RESOURCE_L2DATA])
l2_qos_cfg_update(&r->alloc_enabled);
if (r == &rdt_resources_all[RDT_RESOURCE_L3DATA])
l3_qos_cfg_update(&r->alloc_enabled);
}
/*
* Enable or disable the MBA software controller
* which helps user specify bandwidth in MBps.