RE: [PATCH v1 1/2] perf,x86: add Intel Memory Bandwidth Monitoring (MBM) PMU

From: Juvva, Kanaka D
Date: Fri Jun 12 2015 - 18:39:11 EST


Good patch!

> -----Original Message-----
> From: Kanaka Juvva [mailto:kanaka.d.juvva@xxxxxxxxxxxxxxx]
> Sent: Friday, June 12, 2015 12:58 AM
> To: Juvva, Kanaka D; Williamson, Glenn P; Fleming, Matt; Auld, Will;
> andi@xxxxxxxxxxxxxx; Narayan, Ananth S; Herdrich, Andrew J; tglx@xxxxxxxxxxxxx;
> x86@xxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; mingo@xxxxxxxxxx;
> hpa@xxxxxxxxx; luto@xxxxxxxxxxxxxx; dvlasenk@xxxxxxxxxx; bp@xxxxxxxxx;
> dave.hansen@xxxxxxxxxxxxxxx; peter.p.waskiewicz.jr@xxxxxxxxx;
> imammedo@xxxxxxxxxx; bp@xxxxxxx; ross.zwisler@xxxxxxxxxxxxxxx;
> jacob.w.shin@xxxxxxxxx; Brandewie, Dirk J; Shivappa, Vikas; Verplanke, Edwin;
> Kantecki, Tomasz
> Subject: [PATCH v1 1/2] perf,x86: add Intel Memory Bandwidth Monitoring
> (MBM) PMU
>
> This patch adds Memory Bandwidth Monitoring events to the exitsing intel_cqm
> pmu in the Linux Kernel.
>
> Intel MBM builds on Cache Monitoring Technology (CMT) infrastructure to allow
> monitoring of bandwidth from one level of the cache hierarchy to the next - in
> this case focusing on the L3 cache, which is typically backed directly by system
> memory. As a result of this implementation, memory bandwidth can be
> monitored.
>
> MBM counters are available in Intel Xeon CPUs. The following events are
> implemented in the kernel and expose two MBM counters via perf_event
> interface:
>
> - llc_local_bw: bandwidth consumption of all coress on socket
> - llc_total_bw: bandwidth consumption of all cores on socket + bandwidth
> for QPI accesses
>
> At present, the MBM events are checked at one second interval provided by the
> HRTIMER of the MBM event. MBM counters can overflow atmost once in a
> second and thus must be read atleast once in a second. Overflow is detected
> and handled. Cumulative average value is calculated for each bandwidth type
> upon reading a new value from the MSR.
>
> Signed-off-by: Kanaka Juvva <kanaka.d.juvva@xxxxxxxxxxxxxxx>
> ---
> arch/x86/include/asm/cpufeature.h | 2 +
> arch/x86/kernel/cpu/common.c | 5 +-
> arch/x86/kernel/cpu/perf_event_intel_cqm.c | 619
> +++++++++++++++++++++++++++--
> 3 files changed, 585 insertions(+), 41 deletions(-)
>
> diff --git a/arch/x86/include/asm/cpufeature.h
> b/arch/x86/include/asm/cpufeature.h
> index 3d6606f..26505f6 100644
> --- a/arch/x86/include/asm/cpufeature.h
> +++ b/arch/x86/include/asm/cpufeature.h
> @@ -248,6 +248,8 @@
>
> /* Intel-defined CPU QoS Sub-leaf, CPUID level 0x0000000F:0 (edx), word 11 */
> #define X86_FEATURE_CQM_LLC (11*32+ 1) /* LLC QoS if 1 */
> +#define X86_FEATURE_CQM_MBM_TOTAL (12*32+1) /* LLC Total MBM
> monitoring
> +*/ #define X86_FEATURE_CQM_MBM_LOCAL (12*32+2) /* LLC Local MBM
> +monitoring */
>
> /* Intel-defined CPU QoS Sub-leaf, CPUID level 0x0000000F:1 (edx), word 12 */
> #define X86_FEATURE_CQM_OCCUP_LLC (12*32+ 0) /* LLC occupancy
> monitoring if 1 */ diff --git a/arch/x86/kernel/cpu/common.c
> b/arch/x86/kernel/cpu/common.c index a62cf04..d046f46 100644
> --- a/arch/x86/kernel/cpu/common.c
> +++ b/arch/x86/kernel/cpu/common.c
> @@ -660,7 +660,10 @@ void get_cpu_cap(struct cpuinfo_x86 *c)
> /* QoS sub-leaf, EAX=0Fh, ECX=1 */
> cpuid_count(0x0000000F, 1, &eax, &ebx, &ecx, &edx);
> c->x86_capability[12] = edx;
> - if (cpu_has(c, X86_FEATURE_CQM_OCCUP_LLC)) {
> + if ((cpu_has(c, X86_FEATURE_CQM_OCCUP_LLC))
> + || ((cpu_has(c, X86_FEATURE_CQM_MBM_TOTAL))
> + || (cpu_has(c,
> X86_FEATURE_CQM_MBM_LOCAL)))) {
> +
> c->x86_cache_max_rmid = ecx;
> c->x86_cache_occ_scale = ebx;
> }
> diff --git a/arch/x86/kernel/cpu/perf_event_intel_cqm.c
> b/arch/x86/kernel/cpu/perf_event_intel_cqm.c
> index 1880761..d210c5c 100644
> --- a/arch/x86/kernel/cpu/perf_event_intel_cqm.c
> +++ b/arch/x86/kernel/cpu/perf_event_intel_cqm.c
> @@ -12,10 +12,20 @@
> #define MSR_IA32_PQR_ASSOC 0x0c8f
> #define MSR_IA32_QM_CTR 0x0c8e
> #define MSR_IA32_QM_EVTSEL 0x0c8d
> +#define MAX_MBM_CNTR 0xffffff
> +#define MBM_SOCKET_MAX 8
> +#define MBM_TIME_DELTA_MAX 1000
> +#define MBM_TIME_DELTA_MIN 1000
> +#define MBM_SCALING_FACTOR 1000
> +#define MBM_SCALING_HALF (MBM_SCALING_FACTOR/2)
> +#define MBM_FIFO_SIZE_MIN 10
> +#define MBM_FIFO_SIZE_MAX 300
>
> -static u32 cqm_max_rmid = -1;
> -static unsigned int cqm_l3_scale; /* supposedly cacheline size */
>
> +static u32 cqm_max_rmid = -1;
> +static unsigned int cqm_l3_scale;/* supposedly cacheline size */ static
> +unsigned mbm_window_size = MBM_FIFO_SIZE_MIN; static bool cqm_llc_occ,
> +cqm_mbm;
> /**
> * struct intel_pqr_state - State cache for the PQR MSR
> * @rmid: The cached Resource Monitoring ID
> @@ -42,6 +52,34 @@ struct intel_pqr_state {
> * interrupts disabled, which is sufficient for the protection.
> */
> static DEFINE_PER_CPU(struct intel_pqr_state, pqr_state);
> +static DEFINE_PER_CPU(struct mbm_pmu *, mbm_pmu); static
> +DEFINE_PER_CPU(struct mbm_pmu *, mbm_pmu_to_free);
> +
> +/*
> + * mbm pmu is used for storing mbm_local and mbm_total
> + * events
> + */
> +struct mbm_pmu {
> + spinlock_t lock;
> + int n_active; /* number of active events */
> + struct list_head active_list;
> + struct pmu *pmu; /* pointer to mbm perf_event */
> + ktime_t timer_interval; /* in ktime_t unit */
> + struct hrtimer hrtimer;
> +};
> +
> +struct sample {
> + u64 bytes; /* mbm counter value read*/
> + u64 cum_avg; /* current running average of bandwidth */
> + ktime_t prev_time;
> + u64 index; /* current sample no */
> + u32 mbmfifo[MBM_FIFO_SIZE_MAX]; /* window of last n bw values */
> + u32 fifoin; /* mbmfifo in counter for sliding window */
> + u32 fifoout; /* mbmfifo out counter for sliding window */ };
> +
> +struct sample *mbm_total; /* curent stats for mbm_total events */
> +struct sample *mbm_local; /* current stats for mbm_local events */
>
> /*
> * Protects cache_cgroups and cqm_rmid_free_lru and cqm_rmid_limbo_lru.
> @@ -66,6 +104,9 @@ static cpumask_t cqm_cpumask;
> #define RMID_VAL_UNAVAIL (1ULL << 62)
>
> #define QOS_L3_OCCUP_EVENT_ID (1 << 0)
> +#define QOS_MBM_TOTAL_EVENT_ID (1 << 1) #define
> QOS_MBM_LOCAL_EVENT_ID
> +0x3
> +
>
> #define QOS_EVENT_MASK QOS_L3_OCCUP_EVENT_ID
>
> @@ -90,7 +131,8 @@ static u32 intel_cqm_rotation_rmid;
> */
> static inline bool __rmid_valid(u32 rmid) {
> - if (!rmid || rmid == INVALID_RMID)
> + WARN_ON_ONCE(rmid > cqm_max_rmid);
> + if (!rmid || (rmid == INVALID_RMID) || (rmid > cqm_max_rmid))
> return false;
>
> return true;
> @@ -125,6 +167,7 @@ struct cqm_rmid_entry {
> enum rmid_recycle_state state;
> struct list_head list;
> unsigned long queue_time;
> + bool config;
> };
>
> /*
> @@ -176,6 +219,17 @@ static inline struct cqm_rmid_entry *__rmid_entry(u32
> rmid)
> return entry;
> }
>
> +static void mbm_reset_stats(u32 rmid)
> +{
> + u32 vrmid = topology_physical_package_id(smp_processor_id()) *
> + cqm_max_rmid + rmid;
> +
> + if ((!cqm_mbm) || (!mbm_local) || (!mbm_total))
> + return;
> + memset(&mbm_local[vrmid], 0, sizeof(struct sample));
> + memset(&mbm_total[vrmid], 0, sizeof(struct sample)); }
> +
> /*
> * Returns < 0 on fail.
> *
> @@ -192,6 +246,7 @@ static u32 __get_rmid(void)
>
> entry = list_first_entry(&cqm_rmid_free_lru, struct cqm_rmid_entry,
> list);
> list_del(&entry->list);
> + mbm_reset_stats(entry->rmid);
>
> return entry->rmid;
> }
> @@ -207,6 +262,7 @@ static void __put_rmid(u32 rmid)
>
> entry->queue_time = jiffies;
> entry->state = RMID_YOUNG;
> + mbm_reset_stats(rmid);
>
> list_add_tail(&entry->list, &cqm_rmid_limbo_lru); } @@ -232,6 +288,8
> @@ static int intel_cqm_setup_rmid_cache(void)
>
> INIT_LIST_HEAD(&entry->list);
> entry->rmid = r;
> + entry->config = false;
> +
> cqm_rmid_ptrs[r] = entry;
>
> list_add_tail(&entry->list, &cqm_rmid_free_lru); @@ -254,6
> +312,8 @@ fail:
> kfree(cqm_rmid_ptrs[r]);
>
> kfree(cqm_rmid_ptrs);
> + kfree(mbm_local);
> + kfree(mbm_total);
> return -ENOMEM;
> }
>
> @@ -403,9 +463,11 @@ static void __intel_cqm_event_count(void *info);
> static u32 intel_cqm_xchg_rmid(struct perf_event *group, u32 rmid) {
> struct perf_event *event;
> +
> struct list_head *head = &group->hw.cqm_group_entry;
> u32 old_rmid = group->hw.cqm_rmid;
>
> +
> lockdep_assert_held(&cache_mutex);
>
> /*
> @@ -494,6 +556,166 @@ static bool intel_cqm_sched_in_event(u32 rmid)
> return false;
> }
>
> +static u32 mbm_fifo_sum_lastn_out(int rmid, bool is_localbw) {
> + u32 val = 0, i, j, index;
> +
> + if (is_localbw) {
> + if (++mbm_local[rmid].fifoout >= mbm_window_size)
> + mbm_local[rmid].fifoout = 0;
> + index = mbm_local[rmid].fifoout;
> + for (i = 0; i < mbm_window_size - 1; i++) {
> + if (index + i >= mbm_window_size)
> + j = index + i - mbm_window_size;
> + else
> + j = index + i;
> + val += mbm_local[rmid].mbmfifo[j];
> + }
> + return val;
> + }
> +
> + if (++mbm_total[rmid].fifoout >= mbm_window_size)
> + mbm_total[rmid].fifoout = 0;
> + index = mbm_total[rmid].fifoout;
> + for (i = 0; i < mbm_window_size - 1; i++) {
> + if (index + i >= mbm_window_size)
> + j = index + i - mbm_window_size;
> + else
> + j = index + i;
> + val += mbm_total[rmid].mbmfifo[j];
> + }
> + return val;
> +}
> +
> +static int mbm_fifo_in(int rmid, u32 val, bool is_localbw) {
> + if (is_localbw) {
> + mbm_local[rmid].mbmfifo[mbm_local[rmid].fifoin] = val;
> + if (++mbm_local[rmid].fifoin >= mbm_window_size)
> + mbm_local[rmid].fifoin = 0;
> + } else {
> + mbm_total[rmid].mbmfifo[mbm_total[rmid].fifoin] = val;
> + if (++mbm_total[rmid].fifoin >= mbm_window_size)
> + mbm_total[rmid].fifoin = 0;
> + }
> + return 0;
> +}
> +
> +/*
> + * __rmid_read_mbm checks whether it is LOCAL or GLOBAL MBM event and
> +reads
> + * its MSR counter. if (MSR current value < MSR previous value) it is
> +an
> + * overflow and overflow is handled. If MSR is read within last 100ms,
> + * then the value is ignored; this will suppress small deltas. We don't
> + * process MBM samples that are within 100ms. Bandwidth is calculated as:
> + * bandwidth = difference of last two msr counter values/time difference.
> + * cum_avg = Running Average bandwidth of last 'n' samples that are
> +processed
> + * Sliding window is used to save the last 'n' samples. Hence,
> + * n = sliding_window_size
> + * cum_avg is scaled down by a factor MBM_SCALING_FACTOR and rounded
> +to nearest
> + * integer. User interface reads the BW in MB/sec.
> + * Rounding algorithm : (X + 0.5):
> + * where X is scaled BW value. To avoid floating point arithmetic :
> + * BW- unscaled value
> + * (BW + MBM_SCALING_HALF)/MBM_SCALING_FACTOR is computed which
> gives
> +the
> + * scaled bandwidth.
> + */
> +static u64 __rmid_read_mbm(unsigned int rmid, bool read_mbm_local) {
> + u64 val, tmp, diff_time, cma, bytes, index;
> + bool overflow = false;
> + ktime_t cur_time;
> + u32 tmp32 = rmid;
> + u32 vrmid = topology_physical_package_id(smp_processor_id()) *
> + cqm_max_rmid + rmid;
> +
> + rmid = vrmid;
> + cur_time = ktime_get_real();
> + if (read_mbm_local) {
> + cma = mbm_local[rmid].cum_avg;
> + diff_time = ktime_ms_delta(cur_time,
> + mbm_local[rmid].prev_time);
> + if (diff_time < 100)
> + return cma;
> + mbm_local[rmid].prev_time = ktime_set(0,
> + (unsigned long)ktime_to_ns(cur_time));
> + bytes = mbm_local[rmid].bytes;
> + index = mbm_local[rmid].index;
> + rmid = tmp32;
> + wrmsr(MSR_IA32_QM_EVTSEL, QOS_MBM_LOCAL_EVENT_ID,
> rmid);
> + } else {
> + cma = mbm_total[rmid].cum_avg;
> + diff_time = ktime_ms_delta(cur_time,
> + mbm_total[rmid].prev_time);
> + if (diff_time < 100)
> + return cma;
> + mbm_total[rmid].prev_time = ktime_set(0,
> + (unsigned long)ktime_to_ns(cur_time));
> + bytes = mbm_total[rmid].bytes;
> + index = mbm_total[rmid].index;
> + rmid = tmp32;
> + wrmsr(MSR_IA32_QM_EVTSEL, QOS_MBM_TOTAL_EVENT_ID,
> rmid);
> + }
> + rdmsrl(MSR_IA32_QM_CTR, val);
> + if (val & (RMID_VAL_ERROR | RMID_VAL_UNAVAIL))
> + return val;
> +
> + tmp = val;
> + if (val < bytes) /* overflow handle it */ {
> + val = MAX_MBM_CNTR - bytes + val;
> + overflow = true;
> + } else
> + val = val - bytes;
> + if (diff_time < MBM_TIME_DELTA_MAX - MBM_TIME_DELTA_MIN)
> + val = (val * MBM_TIME_DELTA_MAX) / diff_time;
> +
> + if ((diff_time > MBM_TIME_DELTA_MAX) && (!cma))
> + /* First sample, we can't use the time delta */
> + diff_time = MBM_TIME_DELTA_MAX;
> +
> + rmid = vrmid;
> + if ((diff_time <= MBM_TIME_DELTA_MAX + MBM_TIME_DELTA_MIN)
> ||
> + overflow) {
> + int bw, ret;
> +
> + if (index & (index < mbm_window_size))
> + val = cma * MBM_SCALING_FACTOR + val / index -
> + cma / index;
> + val = (val + MBM_SCALING_HALF) / MBM_SCALING_FACTOR;
> + if (index >= mbm_window_size) {
> + /*
> + * Compute the sum of recent n-1 samples and slide the
> + * window by 1
> + */
> + ret = mbm_fifo_sum_lastn_out(rmid, read_mbm_local);
> + /* recalculate the running average with current bw */
> + ret = (ret + val) / mbm_window_size;
> + if (ret < 0)
> + ret = 0;
> + bw = val;
> + val = ret;
> + } else
> + bw = val;
> + /* save the recent bw in fifo */
> + mbm_fifo_in(rmid, bw, read_mbm_local);
> +
> + if (read_mbm_local) {
> + mbm_local[rmid].index++;
> + mbm_local[rmid].cum_avg = val;
> + mbm_local[rmid].bytes = tmp;
> + mbm_local[rmid].prev_time = ktime_set(0,
> + (unsigned long)ktime_to_ns(cur_time));
> + } else {
> + mbm_total[rmid].index++;
> + mbm_total[rmid].cum_avg = val;
> + mbm_total[rmid].bytes = tmp;
> + mbm_total[rmid].prev_time = ktime_set(0,
> + (unsigned long)ktime_to_ns(cur_time));
> + }
> + return val;
> + }
> + return cma;
> +}
> +
> /*
> * Initially use this constant for both the limbo queue time and the
> * rotation timer interval, pmu::hrtimer_interval_ms.
> @@ -568,7 +790,8 @@ static bool intel_cqm_rmid_stabilize(unsigned int
> *available)
> /*
> * Test whether an RMID is free for each package.
> */
> - on_each_cpu_mask(&cqm_cpumask, intel_cqm_stable, NULL, true);
> + if (entry->config)
> + on_each_cpu_mask(&cqm_cpumask, intel_cqm_stable, NULL,
> true);
>
> list_for_each_entry_safe(entry, tmp, &cqm_rmid_limbo_lru, list) {
> /*
> @@ -846,8 +1069,9 @@ static void intel_cqm_setup_event(struct perf_event
> *event,
> struct perf_event **group)
> {
> struct perf_event *iter;
> - bool conflict = false;
> +
> u32 rmid;
> + bool conflict = false;
>
> list_for_each_entry(iter, &cache_groups, hw.cqm_groups_entry) {
> rmid = iter->hw.cqm_rmid;
> @@ -875,6 +1099,40 @@ static void intel_cqm_setup_event(struct perf_event
> *event,
> event->hw.cqm_rmid = rmid;
> }
>
> +static void intel_cqm_event_update(struct perf_event *event) {
> + unsigned int rmid;
> + u64 val = 0;
> +
> + /*
> + * Task events are handled by intel_cqm_event_count().
> + */
> + if (event->cpu == -1)
> + return;
> +
> + rmid = event->hw.cqm_rmid;
> + if (!__rmid_valid(rmid))
> + return;
> +
> + switch (event->attr.config) {
> + case QOS_MBM_TOTAL_EVENT_ID:
> + val = __rmid_read_mbm(rmid, false);
> + break;
> + case QOS_MBM_LOCAL_EVENT_ID:
> + val = __rmid_read_mbm(rmid, true);
> + break;
> + default:
> + break;
> + }
> + /*
> + * Ignore this reading on error states and do not update the value.
> + */
> + if (val & (RMID_VAL_ERROR | RMID_VAL_UNAVAIL))
> + return;
> +
> + local64_set(&event->count, val);
> +}
> +
> static void intel_cqm_event_read(struct perf_event *event) {
> unsigned long flags;
> @@ -887,6 +1145,10 @@ static void intel_cqm_event_read(struct perf_event
> *event)
> if (event->cpu == -1)
> return;
>
> + if ((event->attr.config & QOS_MBM_TOTAL_EVENT_ID) ||
> + (event->attr.config & QOS_MBM_LOCAL_EVENT_ID))
> + intel_cqm_event_update(event);
> +
> raw_spin_lock_irqsave(&cache_lock, flags);
> rmid = event->hw.cqm_rmid;
>
> @@ -906,6 +1168,28 @@ out:
> raw_spin_unlock_irqrestore(&cache_lock, flags); }
>
> +static void __intel_cqm_event_total_bw_count(void *info) {
> + struct rmid_read *rr = info;
> + u64 val;
> +
> + val = __rmid_read_mbm(rr->rmid, false);
> + if (val & (RMID_VAL_ERROR | RMID_VAL_UNAVAIL))
> + return;
> + atomic64_add(val, &rr->value);
> +}
> +
> +static void __intel_cqm_event_local_bw_count(void *info) {
> + struct rmid_read *rr = info;
> + u64 val;
> +
> + val = __rmid_read_mbm(rr->rmid, true);
> + if (val & (RMID_VAL_ERROR | RMID_VAL_UNAVAIL))
> + return;
> + atomic64_add(val, &rr->value);
> +}
> +
> static void __intel_cqm_event_count(void *info) {
> struct rmid_read *rr = info;
> @@ -967,7 +1251,21 @@ static u64 intel_cqm_event_count(struct perf_event
> *event)
> if (!__rmid_valid(rr.rmid))
> goto out;
>
> - on_each_cpu_mask(&cqm_cpumask, __intel_cqm_event_count, &rr, 1);
> + switch (event->attr.config) {
> + case QOS_L3_OCCUP_EVENT_ID:
> + on_each_cpu_mask(&cqm_cpumask,
> __intel_cqm_event_count, &rr, 1);
> + break;
> + case QOS_MBM_TOTAL_EVENT_ID:
> + on_each_cpu_mask(&cqm_cpumask,
> __intel_cqm_event_total_bw_count,
> + &rr, 1);
> + break;
> + case QOS_MBM_LOCAL_EVENT_ID:
> + on_each_cpu_mask(&cqm_cpumask,
> __intel_cqm_event_local_bw_count,
> + &rr, 1);
> + break;
> + default:
> + break;
> + }
>
> raw_spin_lock_irqsave(&cache_lock, flags);
> if (event->hw.cqm_rmid == rr.rmid)
> @@ -977,6 +1275,39 @@ out:
> return __perf_event_count(event);
> }
>
> +static void mbm_start_hrtimer(struct mbm_pmu *pmu) {
> + __hrtimer_start_range_ns(&(pmu->hrtimer),
> + pmu->timer_interval, 0,
> + HRTIMER_MODE_REL_PINNED, 0);
> +}
> +
> +static void mbm_stop_hrtimer(struct mbm_pmu *pmu) {
> + hrtimer_cancel(&pmu->hrtimer);
> +}
> +
> +static enum hrtimer_restart mbm_hrtimer_handle(struct hrtimer *hrtimer)
> +{
> + struct mbm_pmu *pmu = __this_cpu_read(mbm_pmu);
> + struct perf_event *event;
> +
> + if (!pmu->n_active)
> + return HRTIMER_NORESTART;
> + list_for_each_entry(event, &pmu->active_list, active_entry)
> + intel_cqm_event_update(event);
> + hrtimer_forward_now(hrtimer, pmu->timer_interval);
> + return HRTIMER_RESTART;
> +}
> +
> +static void mbm_hrtimer_init(struct mbm_pmu *pmu) {
> + struct hrtimer *hr = &pmu->hrtimer;
> +
> + hrtimer_init(hr, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
> + hr->function = mbm_hrtimer_handle;
> +}
> +
> static void intel_cqm_event_start(struct perf_event *event, int mode) {
> struct intel_pqr_state *state = this_cpu_ptr(&pqr_state); @@ -995,19
> +1326,48 @@ static void intel_cqm_event_start(struct perf_event *event, int
> mode)
> }
>
> state->rmid = rmid;
> + if (event->attr.config & QOS_L3_OCCUP_EVENT_ID) {
> + struct cqm_rmid_entry *entry;
> +
> + entry = __rmid_entry(rmid);
> + entry->config = true;
> + }
> wrmsr(MSR_IA32_PQR_ASSOC, rmid, state->closid);
> +
> + if (((event->attr.config & QOS_MBM_TOTAL_EVENT_ID) ||
> + (event->attr.config & QOS_MBM_LOCAL_EVENT_ID)) &&
> (cqm_mbm)) {
> + int cpu = get_cpu();
> + struct mbm_pmu *pmu = per_cpu(mbm_pmu, cpu);
> +
> + if (pmu) {
> + if (pmu->n_active == 0)
> + mbm_hrtimer_init(pmu);
> + pmu->n_active++;
> + list_add_tail(&event->active_entry,
> + &pmu->active_list);
> + if (pmu->n_active == 1)
> + mbm_start_hrtimer(pmu);
> + }
> + put_cpu();
> + }
> }
>
> static void intel_cqm_event_stop(struct perf_event *event, int mode) {
> struct intel_pqr_state *state = this_cpu_ptr(&pqr_state);
> + struct mbm_pmu *pmu = __this_cpu_read(mbm_pmu);
>
> if (event->hw.cqm_state & PERF_HES_STOPPED)
> return;
>
> event->hw.cqm_state |= PERF_HES_STOPPED;
>
> - intel_cqm_event_read(event);
> + if (event->attr.config & QOS_L3_OCCUP_EVENT_ID)
> + intel_cqm_event_read(event);
> +
> + if ((event->attr.config & QOS_MBM_TOTAL_EVENT_ID) ||
> + (event->attr.config & QOS_MBM_LOCAL_EVENT_ID))
> + intel_cqm_event_update(event);
>
> if (!--state->rmid_usecnt) {
> state->rmid = 0;
> @@ -1015,8 +1375,18 @@ static void intel_cqm_event_stop(struct perf_event
> *event, int mode)
> } else {
> WARN_ON_ONCE(!state->rmid);
> }
> +
> + if (pmu) {
> + WARN_ON_ONCE(pmu->n_active <= 0);
> + pmu->n_active--;
> + if (pmu->n_active == 0)
> + mbm_stop_hrtimer(pmu);
> + list_del(&event->active_entry);
> + }
> +
> }
>
> +
> static int intel_cqm_event_add(struct perf_event *event, int mode) {
> unsigned long flags;
> @@ -1082,7 +1452,9 @@ static int intel_cqm_event_init(struct perf_event
> *event)
> if (event->attr.type != intel_cqm_pmu.type)
> return -ENOENT;
>
> - if (event->attr.config & ~QOS_EVENT_MASK)
> + if (((event->attr.config & ~QOS_EVENT_MASK) &&
> + (event->attr.config & ~QOS_MBM_TOTAL_EVENT_ID)) &&
> + (event->attr.config & ~QOS_MBM_LOCAL_EVENT_ID))
> return -EINVAL;
>
> /* unsupported modes and filters */
> @@ -1137,18 +1509,63 @@ EVENT_ATTR_STR(llc_occupancy.unit,
> intel_cqm_llc_unit, "Bytes"); EVENT_ATTR_STR(llc_occupancy.scale,
> intel_cqm_llc_scale, NULL); EVENT_ATTR_STR(llc_occupancy.snapshot,
> intel_cqm_llc_snapshot, "1");
>
> -static struct attribute *intel_cqm_events_attr[] = {
> +EVENT_ATTR_STR(llc_total_bw, intel_cqm_llc_total_bw, "event=0x02");
> +EVENT_ATTR_STR(llc_total_bw.per-pkg, intel_cqm_llc_total_bw_pkg, "1");
> +EVENT_ATTR_STR(llc_total_bw.unit, intel_cqm_llc_total_bw_unit,
> +"MB/sec"); EVENT_ATTR_STR(llc_total_bw.scale,
> +intel_cqm_llc_total_bw_scale, NULL);
> +EVENT_ATTR_STR(llc_total_bw.snapshot, intel_cqm_llc_total_bw_snapshot,
> +"1");
> +
> +EVENT_ATTR_STR(llc_local_bw, intel_cqm_llc_local_bw, "event=0x03");
> +EVENT_ATTR_STR(llc_local_bw.per-pkg, intel_cqm_llc_local_bw_pkg, "1");
> +EVENT_ATTR_STR(llc_local_bw.unit, intel_cqm_llc_local_bw_unit,
> +"MB/sec"); EVENT_ATTR_STR(llc_local_bw.scale,
> +intel_cqm_llc_local_bw_scale, NULL);
> +EVENT_ATTR_STR(llc_local_bw.snapshot, intel_cqm_llc_local_bw_snapshot,
> +"1");
> +
> +static struct attribute *intel_cmt_events_attr[] = {
> + EVENT_PTR(intel_cqm_llc),
> + EVENT_PTR(intel_cqm_llc_pkg),
> + EVENT_PTR(intel_cqm_llc_unit),
> + EVENT_PTR(intel_cqm_llc_scale),
> + EVENT_PTR(intel_cqm_llc_snapshot),
> + NULL,
> +};
> +
> +static struct attribute *intel_mbm_events_attr[] = {
> + EVENT_PTR(intel_cqm_llc_total_bw),
> + EVENT_PTR(intel_cqm_llc_local_bw),
> + EVENT_PTR(intel_cqm_llc_total_bw_pkg),
> + EVENT_PTR(intel_cqm_llc_local_bw_pkg),
> + EVENT_PTR(intel_cqm_llc_total_bw_unit),
> + EVENT_PTR(intel_cqm_llc_local_bw_unit),
> + EVENT_PTR(intel_cqm_llc_total_bw_scale),
> + EVENT_PTR(intel_cqm_llc_local_bw_scale),
> + EVENT_PTR(intel_cqm_llc_total_bw_snapshot),
> + EVENT_PTR(intel_cqm_llc_local_bw_snapshot),
> + NULL,
> +};
> +
> +static struct attribute *intel_cmt_mbm_events_attr[] = {
> EVENT_PTR(intel_cqm_llc),
> + EVENT_PTR(intel_cqm_llc_total_bw),
> + EVENT_PTR(intel_cqm_llc_local_bw),
> EVENT_PTR(intel_cqm_llc_pkg),
> + EVENT_PTR(intel_cqm_llc_total_bw_pkg),
> + EVENT_PTR(intel_cqm_llc_local_bw_pkg),
> EVENT_PTR(intel_cqm_llc_unit),
> + EVENT_PTR(intel_cqm_llc_total_bw_unit),
> + EVENT_PTR(intel_cqm_llc_local_bw_unit),
> EVENT_PTR(intel_cqm_llc_scale),
> + EVENT_PTR(intel_cqm_llc_total_bw_scale),
> + EVENT_PTR(intel_cqm_llc_local_bw_scale),
> EVENT_PTR(intel_cqm_llc_snapshot),
> + EVENT_PTR(intel_cqm_llc_total_bw_snapshot),
> + EVENT_PTR(intel_cqm_llc_local_bw_snapshot),
> NULL,
> };
>
> static struct attribute_group intel_cqm_events_group = {
> .name = "events",
> - .attrs = intel_cqm_events_attr,
> + .attrs = NULL,
> };
>
> PMU_FORMAT_ATTR(event, "config:0-7");
> @@ -1176,6 +1593,19 @@ max_recycle_threshold_show(struct device *dev,
> struct device_attribute *attr, }
>
> static ssize_t
> +sliding_window_size_show(struct device *dev, struct device_attribute *attr,
> + char *page)
> +{
> + ssize_t rv;
> +
> + mutex_lock(&cache_mutex);
> + rv = snprintf(page, PAGE_SIZE-1, "%u\n", mbm_window_size);
> + mutex_unlock(&cache_mutex);
> +
> + return rv;
> +}
> +
> +static ssize_t
> max_recycle_threshold_store(struct device *dev,
> struct device_attribute *attr,
> const char *buf, size_t count)
> @@ -1203,10 +1633,35 @@ max_recycle_threshold_store(struct device *dev,
> return count;
> }
>
> +static ssize_t
> +sliding_window_size_store(struct device *dev,
> + struct device_attribute *attr,
> + const char *buf, size_t count)
> +{
> + unsigned int bytes;
> + int ret;
> +
> + ret = kstrtouint(buf, 0, &bytes);
> + if (ret)
> + return ret;
> +
> + mutex_lock(&cache_mutex);
> + if (bytes > 0 && bytes <= MBM_FIFO_SIZE_MAX)
> + mbm_window_size = bytes;
> + else
> + bytes = MBM_FIFO_SIZE_MIN;
> +
> + mutex_unlock(&cache_mutex);
> +
> + return count;
> +}
> +
> static DEVICE_ATTR_RW(max_recycle_threshold);
> +static DEVICE_ATTR_RW(sliding_window_size);
>
> static struct attribute *intel_cqm_attrs[] = {
> &dev_attr_max_recycle_threshold.attr,
> + &dev_attr_sliding_window_size.attr,
> NULL,
> };
>
> @@ -1241,16 +1696,17 @@ static inline void cqm_pick_event_reader(int cpu)
>
> for_each_cpu(i, &cqm_cpumask) {
> if (phys_id == topology_physical_package_id(i))
> - return; /* already got reader for this socket */
> + return; /* already got reader for this socket */
> }
>
> cpumask_set_cpu(cpu, &cqm_cpumask);
> }
>
> -static void intel_cqm_cpu_prepare(unsigned int cpu)
> +static int intel_cqm_cpu_prepare(unsigned int cpu)
> {
> struct intel_pqr_state *state = &per_cpu(pqr_state, cpu);
> struct cpuinfo_x86 *c = &cpu_data(cpu);
> + struct mbm_pmu *pmu = per_cpu(mbm_pmu, cpu);
>
> state->rmid = 0;
> state->closid = 0;
> @@ -1258,12 +1714,27 @@ static void intel_cqm_cpu_prepare(unsigned int
> cpu)
>
> WARN_ON(c->x86_cache_max_rmid != cqm_max_rmid);
> WARN_ON(c->x86_cache_occ_scale != cqm_l3_scale);
> +
> + if ((!pmu) && (cqm_mbm)) {
> + pmu = kzalloc_node(sizeof(*mbm_pmu), GFP_KERNEL,
> NUMA_NO_NODE);
> + if (!pmu)
> + return -ENOMEM;
> + spin_lock_init(&pmu->lock);
> + INIT_LIST_HEAD(&pmu->active_list);
> + pmu->pmu = &intel_cqm_pmu;
> + pmu->n_active = 0;
> + pmu->timer_interval = ms_to_ktime(MBM_TIME_DELTA_MAX);
> + per_cpu(mbm_pmu, cpu) = pmu;
> + per_cpu(mbm_pmu_to_free, cpu) = NULL;
> + }
> + return 0;
> }
>
> static void intel_cqm_cpu_exit(unsigned int cpu) {
> int phys_id = topology_physical_package_id(cpu);
> int i;
> + struct mbm_pmu *pmu = per_cpu(mbm_pmu, cpu);
>
> /*
> * Is @cpu a designated cqm reader?
> @@ -1280,6 +1751,13 @@ static void intel_cqm_cpu_exit(unsigned int cpu)
> break;
> }
> }
> +
> + /* cancel overflow polling timer for CPU */
> + if (pmu)
> + mbm_stop_hrtimer(pmu);
> + kfree(mbm_local);
> + kfree(mbm_total);
> +
> }
>
> static int intel_cqm_cpu_notifier(struct notifier_block *nb, @@ -1289,7
> +1767,7 @@ static int intel_cqm_cpu_notifier(struct notifier_block *nb,
>
> switch (action & ~CPU_TASKS_FROZEN) {
> case CPU_UP_PREPARE:
> - intel_cqm_cpu_prepare(cpu);
> + return intel_cqm_cpu_prepare(cpu);
> break;
> case CPU_DOWN_PREPARE:
> intel_cqm_cpu_exit(cpu);
> @@ -1305,17 +1783,74 @@ static int intel_cqm_cpu_notifier(struct
> notifier_block *nb, static const struct x86_cpu_id intel_cqm_match[] = {
> { .vendor = X86_VENDOR_INTEL, .feature =
> X86_FEATURE_CQM_OCCUP_LLC },
> {}
> + }, intel_mbm_match[] = {
> + { .vendor = X86_VENDOR_INTEL, .feature =
> X86_FEATURE_CQM_MBM_LOCAL },
> + {}
> };
>
> static int __init intel_cqm_init(void)
> {
> char *str, scale[20];
> - int i, cpu, ret;
> + int i = 0, cpu, ret;
>
> - if (!x86_match_cpu(intel_cqm_match))
> + if (!x86_match_cpu(intel_cqm_match) &&
> + (!x86_match_cpu(intel_mbm_match)))
> return -ENODEV;
>
> cqm_l3_scale = boot_cpu_data.x86_cache_occ_scale;
> + cqm_max_rmid = boot_cpu_data.x86_cache_max_rmid;
> +
> + if (x86_match_cpu(intel_cqm_match)) {
> + cqm_llc_occ = true;
> + intel_cqm_events_group.attrs = intel_cmt_events_attr;
> + } else
> + cqm_llc_occ = false;
> +
> + if (x86_match_cpu(intel_mbm_match)) {
> + u32 mbm_scale_rounded = 0;
> +
> + cqm_mbm = true;
> + cqm_l3_scale = boot_cpu_data.x86_cache_occ_scale;
> + /*
> + * MBM counter values are in bytes. To conver this to MB/sec,
> + * we scale the MBM scale factor by 1000. Another 1000 factor
> + * scaling down is done
> + * after reading the counter val i.e. in the function
> + * __rmid_read_mbm()
> + */
> + mbm_scale_rounded = (cqm_l3_scale + 500) / 1000;
> + cqm_max_rmid = boot_cpu_data.x86_cache_max_rmid;
> + snprintf(scale, sizeof(scale), "%u", mbm_scale_rounded);
> + str = kstrdup(scale, GFP_KERNEL);
> + if (!str) {
> + ret = -ENOMEM;
> + goto out;
> + }
> +
> + if (cqm_llc_occ)
> + intel_cqm_events_group.attrs =
> + intel_cmt_mbm_events_attr;
> + else
> + intel_cqm_events_group.attrs =
> intel_mbm_events_attr;
> +
> + event_attr_intel_cqm_llc_local_bw_scale.event_str
> + = event_attr_intel_cqm_llc_total_bw_scale.event_str = str;
> + mbm_local = kzalloc_node(sizeof(struct sample) *
> + (cqm_max_rmid + 1) * MBM_SOCKET_MAX,
> + GFP_KERNEL, NUMA_NO_NODE);
> + if (!mbm_local) {
> + ret = -ENOMEM;
> + goto out;
> + }
> + mbm_total = kzalloc_node(sizeof(struct sample) *
> + (cqm_max_rmid + 1) * MBM_SOCKET_MAX,
> + GFP_KERNEL, NUMA_NO_NODE);
> + if (!mbm_total) {
> + ret = -ENOMEM;
> + goto out;
> + }
> + } else
> + cqm_mbm = false;
>
> /*
> * It's possible that not all resources support the same number @@ -
> 1328,44 +1863,48 @@ static int __init intel_cqm_init(void)
> */
> cpu_notifier_register_begin();
>
> - for_each_online_cpu(cpu) {
> - struct cpuinfo_x86 *c = &cpu_data(cpu);
> + if (cqm_llc_occ) {
> + for_each_online_cpu(cpu) {
> + struct cpuinfo_x86 *c = &cpu_data(cpu);
>
> - if (c->x86_cache_max_rmid < cqm_max_rmid)
> - cqm_max_rmid = c->x86_cache_max_rmid;
> + if (c->x86_cache_max_rmid < cqm_max_rmid)
> + cqm_max_rmid = c->x86_cache_max_rmid;
>
> - if (c->x86_cache_occ_scale != cqm_l3_scale) {
> - pr_err("Multiple LLC scale values, disabling\n");
> - ret = -EINVAL;
> - goto out;
> + if (c->x86_cache_occ_scale != cqm_l3_scale) {
> + pr_err("Multiple LLC scale values, disabling\n");
> + ret = -EINVAL;
> + goto out;
> + }
> }
> - }
>
> - /*
> - * A reasonable upper limit on the max threshold is the number
> - * of lines tagged per RMID if all RMIDs have the same number of
> - * lines tagged in the LLC.
> - *
> - * For a 35MB LLC and 56 RMIDs, this is ~1.8% of the LLC.
> - */
> - __intel_cqm_max_threshold =
> + /*
> + * A reasonable upper limit on the max threshold is the number
> + * of lines tagged per RMID if all RMIDs have the same number
> of
> + * lines tagged in the LLC.
> + *
> + * For a 35MB LLC and 56 RMIDs, this is ~1.8% of the LLC.
> + */
> + __intel_cqm_max_threshold =
> boot_cpu_data.x86_cache_size * 1024 / (cqm_max_rmid + 1);
>
> - snprintf(scale, sizeof(scale), "%u", cqm_l3_scale);
> - str = kstrdup(scale, GFP_KERNEL);
> - if (!str) {
> - ret = -ENOMEM;
> - goto out;
> - }
> + snprintf(scale, sizeof(scale), "%u", cqm_l3_scale);
> + str = kstrdup(scale, GFP_KERNEL);
> + if (!str) {
> + ret = -ENOMEM;
> + goto out;
> + }
>
> - event_attr_intel_cqm_llc_scale.event_str = str;
> + event_attr_intel_cqm_llc_scale.event_str = str;
> + }
>
> ret = intel_cqm_setup_rmid_cache();
> if (ret)
> goto out;
>
> for_each_online_cpu(i) {
> - intel_cqm_cpu_prepare(i);
> + ret = intel_cqm_cpu_prepare(i);
> + if (ret)
> + goto out;
> cqm_pick_event_reader(i);
> }
>
> --
> 2.1.0

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