Mailing List Archive

The resctrl architecture specific code may need to create a domain when
a CPU comes online, it also needs to reset the CPUs PQR_ASSOC register.
The resctrl filesystem code needs to update the rdtgroup_default cpu
mask when cpus are brought online.

Currently this is all done in one function, resctrl_online_cpu().
This will need to be split into architecture and filesystem parts
before resctrl can be moved to /fs/.

Pull the rdtgroup_default update work out as a filesystem specific
cpu_online helper. resctrl_online_cpu() is the obvious name for this,
which means the version in core.c needs renaming.

resctrl_online_cpu() is called by the arch code once it has done the
work to add the new cpu to any domains.

In future patches, resctrl_online_cpu() will take the rdtgroup_mutex
itself.

Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com>
Signed-off-by: James Morse <james.morse@arm.com>
---
arch/x86/kernel/cpu/resctrl/core.c | 11 ++++++-----
arch/x86/kernel/cpu/resctrl/rdtgroup.c | 10 ++++++++++
include/linux/resctrl.h | 1 +
3 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 351319403f84..8e25ea49372e 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -603,19 +603,20 @@ static void clear_closid_rmid(int cpu)
wrmsr(MSR_IA32_PQR_ASSOC, RESCTRL_RESERVED_CLOSID, 0);
}

-static int resctrl_online_cpu(unsigned int cpu)
+static int resctrl_arch_online_cpu(unsigned int cpu)
{
struct rdt_resource *r;
+ int err;

mutex_lock(&rdtgroup_mutex);
for_each_capable_rdt_resource(r)
domain_add_cpu(cpu, r);
- /* The cpu is set in default rdtgroup after online. */
- cpumask_set_cpu(cpu, &rdtgroup_default.cpu_mask);
clear_closid_rmid(cpu);
+
+ err = resctrl_online_cpu(cpu);
mutex_unlock(&rdtgroup_mutex);

- return 0;
+ return err;
}

static void clear_childcpus(struct rdtgroup *r, unsigned int cpu)
@@ -965,7 +966,7 @@ static int __init resctrl_late_init(void)

state = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
"x86/resctrl/cat:online:",
- resctrl_online_cpu, resctrl_offline_cpu);
+ resctrl_arch_online_cpu, resctrl_offline_cpu);
if (state < 0)
return state;

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 8f319e03b449..410b2b451c30 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -3698,6 +3698,16 @@ int resctrl_online_domain(struct rdt_resource *r, struct rdt_domain *d)
return 0;
}

+int resctrl_online_cpu(unsigned int cpu)
+{
+ lockdep_assert_held(&rdtgroup_mutex);
+
+ /* The cpu is set in default rdtgroup after online. */
+ cpumask_set_cpu(cpu, &rdtgroup_default.cpu_mask);
+
+ return 0;
+}
+
/*
* rdtgroup_init - rdtgroup initialization
*
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 03e4f41cd336..5a66d034aa61 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -222,6 +222,7 @@ u32 resctrl_arch_get_config(struct rdt_resource *r, struct rdt_domain *d,
u32 closid, enum resctrl_conf_type type);
int resctrl_online_domain(struct rdt_resource *r, struct rdt_domain *d);
void resctrl_offline_domain(struct rdt_resource *r, struct rdt_domain *d);
+int resctrl_online_cpu(unsigned int cpu);

/**
* resctrl_arch_rmid_read() - Read the eventid counter corresponding to rmid
--
2.39.2