[RFC PATCH v3 09/17] x86/resctrl: Introduce assign state for the mon group

From: Babu Moger
Date: Thu Mar 28 2024 - 21:09:31 EST


The ABMC feature provides an option to the user to assign an RMID to
the hardware counter and monitor the bandwidth for the longer duration.
The assigned RMID will be active until user unassigns the RMID.

Add a new field assign_state in mongroup data structure to represent the
assignment state of the group. This will be when ABMC feature is enabled.

Signed-off-by: Babu Moger <babu.moger@xxxxxxx>
---
v3: Changed the field name to mon_state. Also thie state is not visible to
users directly as part of out global assign approach.

v2: Added check to display "Unsupported" when user tries to access
monitor state when ABMC is not enabled.
---
arch/x86/kernel/cpu/resctrl/internal.h | 9 +++++++++
arch/x86/kernel/cpu/resctrl/rdtgroup.c | 8 ++++++++
2 files changed, 17 insertions(+)

diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 8238ee437369..b559b3a4555e 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -99,6 +99,13 @@ cpumask_any_housekeeping(const struct cpumask *mask, int exclude_cpu)
/* ABMC ENABLE */
#define ABMC_ENABLE BIT(0)

+/*
+ * monitor group's state when ABMC is supported
+ */
+#define ASSIGN_NONE 0
+#define ASSIGN_TOTAL BIT(0)
+#define ASSIGN_LOCAL BIT(1)
+
struct rdt_fs_context {
struct kernfs_fs_context kfc;
bool enable_cdpl2;
@@ -202,12 +209,14 @@ enum rdtgrp_mode {
* @parent: parent rdtgrp
* @crdtgrp_list: child rdtgroup node list
* @rmid: rmid for this rdtgroup
+ * @mon_state: Assignment state of the group
*/
struct mongroup {
struct kernfs_node *mon_data_kn;
struct rdtgroup *parent;
struct list_head crdtgrp_list;
u32 rmid;
+ u32 mon_state;
};

/**
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 2c7583e7b541..54ae2e6bf612 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2473,6 +2473,7 @@ static void resctrl_abmc_msrwrite(void *arg)
static int resctrl_abmc_setup(enum resctrl_res_level l, bool enable)
{
struct rdt_resource *r = &rdt_resources_all[l].r_resctrl;
+ struct rdtgroup *prgrp, *crgrp;
struct rdt_domain *d;

/* Reset the counters bitmap */
@@ -2484,6 +2485,13 @@ static int resctrl_abmc_setup(enum resctrl_res_level l, bool enable)
resctrl_arch_reset_rmid_all(r, d);
}

+ /* Reset assign state for all the monitor groups */
+ list_for_each_entry(prgrp, &rdt_all_groups, rdtgroup_list) {
+ prgrp->mon.mon_state = ASSIGN_NONE;
+ list_for_each_entry(crgrp, &prgrp->mon.crdtgrp_list, mon.crdtgrp_list)
+ crgrp->mon.mon_state = ASSIGN_NONE;
+ }
+
return 0;
}

--
2.34.1