[PATCH v2 10/35] x86/resctrl: Move monitor init work to a resctrl init call

[Dave Martin <Dave.Martin@arm.com>]

From: James Morse <james.morse@arm.com>

rdt_get_mon_l3_config() is called from the architecture's
resctrl_arch_late_init(), and initialises both architecture specific
fields, such as hw_res->mon_scale and resctrl filesystem fields
by calling dom_data_init().

To separate the filesystem and architecture parts of resctrl, this
function needs splitting up.

Add resctrl_mon_resource_init() to do the filesystem specific work,
and call it from resctrl_init(). This runs later, but is still before
the filesystem is mounted and the rmid_ptrs[] array can be used.

Signed-off-by: James Morse <james.morse@arm.com>
---
 arch/x86/kernel/cpu/resctrl/internal.h |  1 +
 arch/x86/kernel/cpu/resctrl/monitor.c  | 24 +++++++++++++++++-------
 arch/x86/kernel/cpu/resctrl/rdtgroup.c |  4 ++++
 3 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 031948322eab..7a0c74779c53 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -540,6 +540,7 @@ int rdtgroup_mondata_show(struct seq_file *m, void *arg);
 void mon_event_read(struct rmid_read *rr, struct rdt_resource *r,
 		    struct rdt_domain *d, struct rdtgroup *rdtgrp,
 		    int evtid, int first);
+int resctrl_mon_resource_init(void);
 void mbm_setup_overflow_handler(struct rdt_domain *dom,
 				unsigned long delay_ms,
 				int exclude_cpu);
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 9f2fafcf78f1..165bd16538e6 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -1003,12 +1003,28 @@ static void l3_mon_evt_init(struct rdt_resource *r)
 		list_add_tail(&mbm_local_event.list, &r->evt_list);
 }
 
+int resctrl_mon_resource_init(void)
+{
+	struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3);
+	int ret;
+
+	if (!r->mon_capable)
+		return 0;
+
+	ret = dom_data_init(r);
+	if (ret)
+		return ret;
+
+	l3_mon_evt_init(r);
+
+	return 0;
+}
+
 int __init rdt_get_mon_l3_config(struct rdt_resource *r)
 {
 	unsigned int mbm_offset = boot_cpu_data.x86_cache_mbm_width_offset;
 	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
 	unsigned int threshold;
-	int ret;
 
 	resctrl_rmid_realloc_limit = boot_cpu_data.x86_cache_size * 1024;
 	hw_res->mon_scale = boot_cpu_data.x86_cache_occ_scale;
@@ -1036,10 +1052,6 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
 	 */
 	resctrl_rmid_realloc_threshold = resctrl_arch_round_mon_val(threshold);
 
-	ret = dom_data_init(r);
-	if (ret)
-		return ret;
-
 	if (rdt_cpu_has(X86_FEATURE_BMEC)) {
 		u32 eax, ebx, ecx, edx;
 
@@ -1057,8 +1069,6 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
 		}
 	}
 
-	l3_mon_evt_init(r);
-
 	r->mon_capable = true;
 
 	return 0;
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 2684a863c727..8c793d2d7a68 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -4140,6 +4140,10 @@ int __init resctrl_init(void)
 
 	rdtgroup_setup_default();
 
+	ret = resctrl_mon_resource_init();
+	if (ret)
+		return ret;
+
 	ret = sysfs_create_mount_point(fs_kobj, "resctrl");
 	if (ret)
 		return ret;
-- 
2.34.1