x86/intel_rdt/mbm: Basic counting of MBM events (total and local)

Check CPUID bits for whether each of the MBM events is supported.
Allocate space for each RMID for each counter in each domain to save
previous MSR counter value and running total of data.
Create files in each of the monitor directories.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-27-git-send-email-vikas.shivappa@linux.intel.com

diff --git a/arch/x86/kernel/cpu/intel_rdt.c b/arch/x86/kernel/cpu/intel_rdt.c
index f12bb91b8c667fcd51a2acf9756761a70d9c093c..4c17a7060dfdb7d161f3dc83ac9e9a5d123c40a5 100644 (file)
--- a/arch/x86/kernel/cpu/intel_rdt.c
+++ b/arch/x86/kernel/cpu/intel_rdt.c
@@ -420,6 +420,8 @@ static int domain_setup_ctrlval(struct rdt_resource *r, struct rdt_domain *d)
 
 static int domain_setup_mon_state(struct rdt_resource *r, struct rdt_domain *d)
 {
+       size_t tsize;
+
        if (is_llc_occupancy_enabled()) {
                d->rmid_busy_llc = kcalloc(BITS_TO_LONGS(r->num_rmid),
                                           sizeof(unsigned long),
@@ -427,6 +429,23 @@ static int domain_setup_mon_state(struct rdt_resource *r, struct rdt_domain *d)
                if (!d->rmid_busy_llc)
                        return -ENOMEM;
        }
+       if (is_mbm_total_enabled()) {
+               tsize = sizeof(*d->mbm_total);
+               d->mbm_total = kcalloc(r->num_rmid, tsize, GFP_KERNEL);
+               if (!d->mbm_total) {
+                       kfree(d->rmid_busy_llc);
+                       return -ENOMEM;
+               }
+       }
+       if (is_mbm_local_enabled()) {
+               tsize = sizeof(*d->mbm_local);
+               d->mbm_local = kcalloc(r->num_rmid, tsize, GFP_KERNEL);
+               if (!d->mbm_local) {
+                       kfree(d->rmid_busy_llc);
+                       kfree(d->mbm_total);
+                       return -ENOMEM;
+               }
+       }
 
        return 0;
 }
@@ -466,6 +485,7 @@ static void domain_add_cpu(int cpu, struct rdt_resource *r)
                return;
 
        d->id = id;
+       cpumask_set_cpu(cpu, &d->cpu_mask);
 
        if (r->alloc_capable && domain_setup_ctrlval(r, d)) {
                kfree(d);
@@ -477,7 +497,6 @@ static void domain_add_cpu(int cpu, struct rdt_resource *r)
                return;
        }
 
-       cpumask_set_cpu(cpu, &d->cpu_mask);
        list_add_tail(&d->list, add_pos);
 
        /*
@@ -509,6 +528,8 @@ static void domain_remove_cpu(int cpu, struct rdt_resource *r)
                        rmdir_mondata_subdir_allrdtgrp(r, d->id);
                kfree(d->ctrl_val);
                kfree(d->rmid_busy_llc);
+               kfree(d->mbm_total);
+               kfree(d->mbm_local);
                list_del(&d->list);
                kfree(d);
        }

diff --git a/arch/x86/kernel/cpu/intel_rdt.h b/arch/x86/kernel/cpu/intel_rdt.h
index 2660d15d17123258ba724d0128a36034e6f2a428..2137d5e5580322171c91078db08f07dec22763d2 100644 (file)
--- a/arch/x86/kernel/cpu/intel_rdt.h
+++ b/arch/x86/kernel/cpu/intel_rdt.h
@@ -19,6 +19,9 @@
 #define QOS_L3_OCCUP_EVENT_ID          0x01
 #define QOS_L3_MBM_TOTAL_EVENT_ID      0x02
 #define QOS_L3_MBM_LOCAL_EVENT_ID      0x03
+
+#define MBM_CNTR_WIDTH                 24
+
 #define RMID_VAL_ERROR                 BIT_ULL(63)
 #define RMID_VAL_UNAVAIL               BIT_ULL(62)
 
@@ -50,6 +53,7 @@ union mon_data_bits {
 
 struct rmid_read {
        struct rdtgroup         *rgrp;
+       struct rdt_domain       *d;
        int                     evtid;
        u64                     val;
 };
@@ -159,6 +163,16 @@ struct rftype {
                         char *buf, size_t nbytes, loff_t off);
 };
 
+/**
+ * struct mbm_state - status for each MBM counter in each domain
+ * @chunks:    Total data moved (multiply by rdt_group.mon_scale to get bytes)
+ * @prev_msr   Value of IA32_QM_CTR for this RMID last time we read it
+ */
+struct mbm_state {
+       u64     chunks;
+       u64     prev_msr;
+};
+
 /**
  * struct rdt_domain - group of cpus sharing an RDT resource
  * @list:      all instances of this resource
@@ -166,6 +180,8 @@ struct rftype {
  * @cpu_mask:  which cpus share this resource
  * @rmid_busy_llc:
  *             bitmap of which limbo RMIDs are above threshold
+ * @mbm_total: saved state for MBM total bandwidth
+ * @mbm_local: saved state for MBM local bandwidth
  * @ctrl_val:  array of cache or mem ctrl values (indexed by CLOSID)
  * @new_ctrl:  new ctrl value to be loaded
  * @have_new_ctrl: did user provide new_ctrl for this domain
@@ -175,6 +191,8 @@ struct rdt_domain {
        int                     id;
        struct cpumask          cpu_mask;
        unsigned long           *rmid_busy_llc;
+       struct mbm_state        *mbm_total;
+       struct mbm_state        *mbm_local;
        u32                     *ctrl_val;
        u32                     new_ctrl;
        bool                    have_new_ctrl;
@@ -230,6 +248,21 @@ static inline bool is_llc_occupancy_enabled(void)
        return (rdt_mon_features & (1 << QOS_L3_OCCUP_EVENT_ID));
 }
 
+static inline bool is_mbm_total_enabled(void)
+{
+       return (rdt_mon_features & (1 << QOS_L3_MBM_TOTAL_EVENT_ID));
+}
+
+static inline bool is_mbm_local_enabled(void)
+{
+       return (rdt_mon_features & (1 << QOS_L3_MBM_LOCAL_EVENT_ID));
+}
+
+static inline bool is_mbm_enabled(void)
+{
+       return (is_mbm_total_enabled() || is_mbm_local_enabled());
+}
+
 /**
  * struct rdt_resource - attributes of an RDT resource
  * @rid:               The index of the resource

diff --git a/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c b/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c
index f44e77dc568b31e87a5ae51476ac5353d1bbc862..cf8e2c776440d7a75076f42ed893722f21a1174f 100644 (file)
--- a/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c
+++ b/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c
@@ -294,6 +294,7 @@ void mon_event_read(struct rmid_read *rr, struct rdt_domain *d,
         */
        rr->rgrp = rdtgrp;
        rr->evtid = evtid;
+       rr->d = d;
        rr->val = 0;
 
        smp_call_function_any(&d->cpu_mask, mon_event_count, rr, 1);

diff --git a/arch/x86/kernel/cpu/intel_rdt_monitor.c b/arch/x86/kernel/cpu/intel_rdt_monitor.c
index 6ae5cf58e50aae962fa37a3ff2df90fa204f4ffd..ef0358b591022c990a7eba464cc379e69fcb06f1 100644 (file)
--- a/arch/x86/kernel/cpu/intel_rdt_monitor.c
+++ b/arch/x86/kernel/cpu/intel_rdt_monitor.c
@@ -296,7 +296,8 @@ void free_rmid(u32 rmid)
 
 static int __mon_event_count(u32 rmid, struct rmid_read *rr)
 {
-       u64 tval;
+       u64 chunks, shift, tval;
+       struct mbm_state *m;
 
        tval = __rmid_read(rmid, rr->evtid);
        if (tval & (RMID_VAL_ERROR | RMID_VAL_UNAVAIL)) {
@@ -307,6 +308,12 @@ static int __mon_event_count(u32 rmid, struct rmid_read *rr)
        case QOS_L3_OCCUP_EVENT_ID:
                rr->val += tval;
                return 0;
+       case QOS_L3_MBM_TOTAL_EVENT_ID:
+               m = &rr->d->mbm_total[rmid];
+               break;
+       case QOS_L3_MBM_LOCAL_EVENT_ID:
+               m = &rr->d->mbm_local[rmid];
+               break;
        default:
                /*
                 * Code would never reach here because
@@ -314,6 +321,14 @@ static int __mon_event_count(u32 rmid, struct rmid_read *rr)
                 */
                return -EINVAL;
        }
+       shift = 64 - MBM_CNTR_WIDTH;
+       chunks = (tval << shift) - (m->prev_msr << shift);
+       chunks >>= shift;
+       m->chunks += chunks;
+       m->prev_msr = tval;
+
+       rr->val += m->chunks;
+       return 0;
 }
 
 /*
@@ -377,6 +392,16 @@ static struct mon_evt llc_occupancy_event = {
        .evtid          = QOS_L3_OCCUP_EVENT_ID,
 };
 
+static struct mon_evt mbm_total_event = {
+       .name           = "mbm_total_bytes",
+       .evtid          = QOS_L3_MBM_TOTAL_EVENT_ID,
+};
+
+static struct mon_evt mbm_local_event = {
+       .name           = "mbm_local_bytes",
+       .evtid          = QOS_L3_MBM_LOCAL_EVENT_ID,
+};
+
 /*
  * Initialize the event list for the resource.
  *
@@ -390,6 +415,10 @@ static void l3_mon_evt_init(struct rdt_resource *r)
 
        if (is_llc_occupancy_enabled())
                list_add_tail(&llc_occupancy_event.list, &r->evt_list);
+       if (is_mbm_total_enabled())
+               list_add_tail(&mbm_total_event.list, &r->evt_list);
+       if (is_mbm_local_enabled())
+               list_add_tail(&mbm_local_event.list, &r->evt_list);
 }
 
 int rdt_get_mon_l3_config(struct rdt_resource *r)