In x86, hardware uses RMID to identify a monitoring group. When a user creates a monitor group these details are not visible. These details can help resctrl debugging. Add RMID(mon_hw_id) to the monitor groups display in resctrl interface. Users can see these details when resctrl is mounted with "-o debug" option. Other architectures do not use "RMID". Use the name mon_hw_id to refer to "RMID" in an effort to keep the naming generic. For example: $cat /sys/fs/resctrl/mon_groups/mon_grp1/mon_hw_id 3 Signed-off-by: Babu Moger <babu.moger@xxxxxxx> --- Documentation/arch/x86/resctrl.rst | 4 ++++ arch/x86/kernel/cpu/resctrl/internal.h | 5 +++++ arch/x86/kernel/cpu/resctrl/rdtgroup.c | 23 +++++++++++++++++++++++ 3 files changed, 32 insertions(+) diff --git a/Documentation/arch/x86/resctrl.rst b/Documentation/arch/x86/resctrl.rst index 54691c8b832d..98b0eb509ed4 100644 --- a/Documentation/arch/x86/resctrl.rst +++ b/Documentation/arch/x86/resctrl.rst @@ -369,6 +369,10 @@ When monitoring is enabled all MON groups will also contain: the sum for all tasks in the CTRL_MON group and all tasks in MON groups. Please see example section for more details on usage. +"mon_hw_id": + Available only with debug option. The identifier used by hardware + for the monitor group. On x86 this is the RMID. + Resource allocation rules ------------------------- diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h index a07fa4329b65..b4910892b0a6 100644 --- a/arch/x86/kernel/cpu/resctrl/internal.h +++ b/arch/x86/kernel/cpu/resctrl/internal.h @@ -296,6 +296,11 @@ struct rdtgroup { * --> RFTYPE_BASE (Files common for both MON and CTRL groups) * Files: cpus, cpus_list, tasks * + * --> RFTYPE_MON (Files only for MON group) + * + * --> RFTYPE_DEBUG (Files to help resctrl debugging) + * File: mon_hw_id + * * --> RFTYPE_CTRL (Files only for CTRL group) * Files: mode, schemata, size * diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c index 55d1b90f460e..ef4b18091e5d 100644 --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c @@ -795,6 +795,22 @@ static int rdtgroup_closid_show(struct kernfs_open_file *of, return ret; } +static int rdtgroup_rmid_show(struct kernfs_open_file *of, + struct seq_file *s, void *v) +{ + struct rdtgroup *rdtgrp; + int ret = 0; + + rdtgrp = rdtgroup_kn_lock_live(of->kn); + if (rdtgrp) + seq_printf(s, "%u\n", rdtgrp->mon.rmid); + else + ret = -ENOENT; + rdtgroup_kn_unlock(of->kn); + + return ret; +} + #ifdef CONFIG_PROC_CPU_RESCTRL /* @@ -1856,6 +1872,13 @@ static struct rftype res_common_files[] = { .seq_show = rdtgroup_tasks_show, .fflags = RFTYPE_BASE, }, + { + .name = "mon_hw_id", + .mode = 0444, + .kf_ops = &rdtgroup_kf_single_ops, + .seq_show = rdtgroup_rmid_show, + .fflags = RFTYPE_MON_BASE | RFTYPE_DEBUG, + }, { .name = "schemata", .mode = 0644, -- 2.34.1