x86/resctrl: Add interface to read mbm_total_bytes_config

The event configuration can be viewed by the user by reading the
configuration file /sys/fs/resctrl/info/L3_MON/mbm_total_bytes_config.  The
event configuration settings are domain specific and will affect all the CPUs in
the domain.

Following are the types of events supported:

  ====  ===========================================================
  Bits   Description
  ====  ===========================================================
  6      Dirty Victims from the QOS domain to all types of memory
  5      Reads to slow memory in the non-local NUMA domain
  4      Reads to slow memory in the local NUMA domain
  3      Non-temporal writes to non-local NUMA domain
  2      Non-temporal writes to local NUMA domain
  1      Reads to memory in the non-local NUMA domain
  0      Reads to memory in the local NUMA domain
  ====  ===========================================================

By default, the mbm_total_bytes_config is set to 0x7f to count all the
event types.

For example:

  $cat /sys/fs/resctrl/info/L3_MON/mbm_total_bytes_config
  0=0x7f;1=0x7f;2=0x7f;3=0x7f

In this case, the event mbm_total_bytes is configured with 0x7f on
domains 0 to 3.

Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Link: https://lore.kernel.org/r/20230113152039.770054-10-babu.moger@amd.com

diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index e0a4002..2e5f57c 100644 (file)
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -1062,6 +1062,7 @@
 /* - AMD: */
 #define MSR_IA32_MBA_BW_BASE           0xc0000200
 #define MSR_IA32_SMBA_BW_BASE          0xc0000280
+#define MSR_IA32_EVT_CFG_BASE          0xc0000400
 
 /* MSR_IA32_VMX_MISC bits */
 #define MSR_IA32_VMX_MISC_INTEL_PT                 (1ULL << 14)

diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 0605b04..8edecc5 100644 (file)
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -30,6 +30,29 @@
  */
 #define MBM_CNTR_WIDTH_OFFSET_MAX (62 - MBM_CNTR_WIDTH_BASE)
 
+/* Reads to Local DRAM Memory */
+#define READS_TO_LOCAL_MEM             BIT(0)
+
+/* Reads to Remote DRAM Memory */
+#define READS_TO_REMOTE_MEM            BIT(1)
+
+/* Non-Temporal Writes to Local Memory */
+#define NON_TEMP_WRITE_TO_LOCAL_MEM    BIT(2)
+
+/* Non-Temporal Writes to Remote Memory */
+#define NON_TEMP_WRITE_TO_REMOTE_MEM   BIT(3)
+
+/* Reads to Local Memory the system identifies as "Slow Memory" */
+#define READS_TO_LOCAL_S_MEM           BIT(4)
+
+/* Reads to Remote Memory the system identifies as "Slow Memory" */
+#define READS_TO_REMOTE_S_MEM          BIT(5)
+
+/* Dirty Victims to All Types of Memory */
+#define DIRTY_VICTIMS_TO_ALL_MEM       BIT(6)
+
+/* Max event bits supported */
+#define MAX_EVT_CONFIG_BITS            GENMASK(6, 0)
 
 struct rdt_fs_context {
        struct kernfs_fs_context        kfc;
@@ -531,5 +554,6 @@ bool has_busy_rmid(struct rdt_resource *r, struct rdt_domain *d);
 void __check_limbo(struct rdt_domain *d, bool force_free);
 void rdt_domain_reconfigure_cdp(struct rdt_resource *r);
 void __init thread_throttle_mode_init(void);
+void __init mbm_config_rftype_init(const char *config);
 
 #endif /* _ASM_X86_RESCTRL_INTERNAL_H */

diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index cf7b6e5..0ff45e3 100644 (file)
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -801,8 +801,10 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
                return ret;
 
        if (rdt_cpu_has(X86_FEATURE_BMEC)) {
-               if (rdt_cpu_has(X86_FEATURE_CQM_MBM_TOTAL))
+               if (rdt_cpu_has(X86_FEATURE_CQM_MBM_TOTAL)) {
                        mbm_total_event.configurable = true;
+                       mbm_config_rftype_init("mbm_total_bytes_config");
+               }
                if (rdt_cpu_has(X86_FEATURE_CQM_MBM_LOCAL))
                        mbm_local_event.configurable = true;
        }

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index bf0bd43..cd4e668 100644 (file)
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1420,6 +1420,93 @@ out:
        return ret;
 }
 
+struct mon_config_info {
+       u32 evtid;
+       u32 mon_config;
+};
+
+#define INVALID_CONFIG_INDEX   UINT_MAX
+
+/**
+ * mon_event_config_index_get - get the hardware index for the
+ *                              configurable event
+ * @evtid: event id.
+ *
+ * Return: 0 for evtid == QOS_L3_MBM_TOTAL_EVENT_ID
+ *         1 for evtid == QOS_L3_MBM_LOCAL_EVENT_ID
+ *         INVALID_CONFIG_INDEX for invalid evtid
+ */
+static inline unsigned int mon_event_config_index_get(u32 evtid)
+{
+       switch (evtid) {
+       case QOS_L3_MBM_TOTAL_EVENT_ID:
+               return 0;
+       case QOS_L3_MBM_LOCAL_EVENT_ID:
+               return 1;
+       default:
+               /* Should never reach here */
+               return INVALID_CONFIG_INDEX;
+       }
+}
+
+static void mon_event_config_read(void *info)
+{
+       struct mon_config_info *mon_info = info;
+       unsigned int index;
+       u32 h;
+
+       index = mon_event_config_index_get(mon_info->evtid);
+       if (index == INVALID_CONFIG_INDEX) {
+               pr_warn_once("Invalid event id %d\n", mon_info->evtid);
+               return;
+       }
+       rdmsr(MSR_IA32_EVT_CFG_BASE + index, mon_info->mon_config, h);
+
+       /* Report only the valid event configuration bits */
+       mon_info->mon_config &= MAX_EVT_CONFIG_BITS;
+}
+
+static void mondata_config_read(struct rdt_domain *d, struct mon_config_info *mon_info)
+{
+       smp_call_function_any(&d->cpu_mask, mon_event_config_read, mon_info, 1);
+}
+
+static int mbm_config_show(struct seq_file *s, struct rdt_resource *r, u32 evtid)
+{
+       struct mon_config_info mon_info = {0};
+       struct rdt_domain *dom;
+       bool sep = false;
+
+       mutex_lock(&rdtgroup_mutex);
+
+       list_for_each_entry(dom, &r->domains, list) {
+               if (sep)
+                       seq_puts(s, ";");
+
+               memset(&mon_info, 0, sizeof(struct mon_config_info));
+               mon_info.evtid = evtid;
+               mondata_config_read(dom, &mon_info);
+
+               seq_printf(s, "%d=0x%02x", dom->id, mon_info.mon_config);
+               sep = true;
+       }
+       seq_puts(s, "\n");
+
+       mutex_unlock(&rdtgroup_mutex);
+
+       return 0;
+}
+
+static int mbm_total_bytes_config_show(struct kernfs_open_file *of,
+                                      struct seq_file *seq, void *v)
+{
+       struct rdt_resource *r = of->kn->parent->priv;
+
+       mbm_config_show(seq, r, QOS_L3_MBM_TOTAL_EVENT_ID);
+
+       return 0;
+}
+
 /* rdtgroup information files for one cache resource. */
 static struct rftype res_common_files[] = {
        {
@@ -1519,6 +1606,12 @@ static struct rftype res_common_files[] = {
                .fflags         = RF_MON_INFO | RFTYPE_RES_CACHE,
        },
        {
+               .name           = "mbm_total_bytes_config",
+               .mode           = 0444,
+               .kf_ops         = &rdtgroup_kf_single_ops,
+               .seq_show       = mbm_total_bytes_config_show,
+       },
+       {
                .name           = "cpus",
                .mode           = 0644,
                .kf_ops         = &rdtgroup_kf_single_ops,
@@ -1624,6 +1717,15 @@ void __init thread_throttle_mode_init(void)
        rft->fflags = RF_CTRL_INFO | RFTYPE_RES_MB;
 }
 
+void __init mbm_config_rftype_init(const char *config)
+{
+       struct rftype *rft;
+
+       rft = rdtgroup_get_rftype_by_name(config);
+       if (rft)
+               rft->fflags = RF_MON_INFO | RFTYPE_RES_CACHE;
+}
+
 /**
  * rdtgroup_kn_mode_restrict - Restrict user access to named resctrl file
  * @r: The resource group with which the file is associated.