Resguardo inicial

linux-7.2.3/arch/x86/events/amd/Makefile

@@ -0,0 +1,10 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_CPU_SUP_AMD)		+= core.o lbr.o
+obj-$(CONFIG_PERF_EVENTS_AMD_BRS)	+= brs.o
+obj-$(CONFIG_PERF_EVENTS_AMD_POWER)	+= power.o
+obj-$(CONFIG_X86_LOCAL_APIC)		+= ibs.o
+obj-$(CONFIG_PERF_EVENTS_AMD_UNCORE)	+= amd-uncore.o
+amd-uncore-objs				:= uncore.o
+ifdef CONFIG_AMD_IOMMU
+obj-$(CONFIG_CPU_SUP_AMD)		+= iommu.o
+endif

linux-7.2.3/arch/x86/events/amd/brs.c

@@ -0,0 +1,432 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Implement support for AMD Fam19h Branch Sampling feature
+ * Based on specifications published in AMD PPR Fam19 Model 01
+ *
+ * Copyright 2021 Google LLC
+ * Contributed by Stephane Eranian <eranian@google.com>
+ */
+#include <linux/kernel.h>
+#include <linux/jump_label.h>
+#include <asm/msr.h>
+#include <asm/cpufeature.h>
+
+#include "../perf_event.h"
+
+#define BRS_POISON	0xFFFFFFFFFFFFFFFEULL /* mark limit of valid entries */
+
+/* Debug Extension Configuration register layout */
+union amd_debug_extn_cfg {
+	__u64 val;
+	struct {
+		__u64	rsvd0:2,  /* reserved */
+			brsmen:1, /* branch sample enable */
+			rsvd4_3:2,/* reserved - must be 0x3 */
+			vb:1,     /* valid branches recorded */
+			rsvd2:10, /* reserved */
+			msroff:4, /* index of next entry to write */
+			rsvd3:4,  /* reserved */
+			pmc:3,    /* #PMC holding the sampling event */
+			rsvd4:37; /* reserved */
+	};
+};
+
+static inline unsigned int brs_from(int idx)
+{
+	return MSR_AMD_SAMP_BR_FROM + 2 * idx;
+}
+
+static inline unsigned int brs_to(int idx)
+{
+	return MSR_AMD_SAMP_BR_FROM + 2 * idx + 1;
+}
+
+static __always_inline void set_debug_extn_cfg(u64 val)
+{
+	/* bits[4:3] must always be set to 11b */
+	native_wrmsrq(MSR_AMD_DBG_EXTN_CFG, val | 3ULL << 3);
+}
+
+static __always_inline u64 get_debug_extn_cfg(void)
+{
+	return native_rdmsrq(MSR_AMD_DBG_EXTN_CFG);
+}
+
+static bool __init amd_brs_detect(void)
+{
+	if (!cpu_feature_enabled(X86_FEATURE_BRS))
+		return false;
+
+	switch (boot_cpu_data.x86) {
+	case 0x19: /* AMD Fam19h (Zen3) */
+		x86_pmu.lbr_nr = 16;
+
+		/* No hardware filtering supported */
+		x86_pmu.lbr_sel_map = NULL;
+		x86_pmu.lbr_sel_mask = 0;
+		break;
+	default:
+		return false;
+	}
+
+	return true;
+}
+
+/*
+ * Current BRS implementation does not support branch type or privilege level
+ * filtering. Therefore, this function simply enforces these limitations. No need for
+ * a br_sel_map. Software filtering is not supported because it would not correlate well
+ * with a sampling period.
+ */
+static int amd_brs_setup_filter(struct perf_event *event)
+{
+	u64 type = event->attr.branch_sample_type;
+
+	/* No BRS support */
+	if (!x86_pmu.lbr_nr)
+		return -EOPNOTSUPP;
+
+	/* Can only capture all branches, i.e., no filtering */
+	if ((type & ~PERF_SAMPLE_BRANCH_PLM_ALL) != PERF_SAMPLE_BRANCH_ANY)
+		return -EINVAL;
+
+	return 0;
+}
+
+static inline int amd_is_brs_event(struct perf_event *e)
+{
+	return (e->hw.config & AMD64_RAW_EVENT_MASK) == AMD_FAM19H_BRS_EVENT;
+}
+
+int amd_brs_hw_config(struct perf_event *event)
+{
+	int ret = 0;
+
+	/*
+	 * Due to interrupt holding, BRS is not recommended in
+	 * counting mode.
+	 */
+	if (!is_sampling_event(event))
+		return -EINVAL;
+
+	/*
+	 * Due to the way BRS operates by holding the interrupt until
+	 * lbr_nr entries have been captured, it does not make sense
+	 * to allow sampling on BRS with an event that does not match
+	 * what BRS is capturing, i.e., retired taken branches.
+	 * Otherwise the correlation with the event's period is even
+	 * more loose:
+	 *
+	 * With retired taken branch:
+	 *   Effective P = P + 16 + X
+	 * With any other event:
+	 *   Effective P = P + Y + X
+	 *
+	 * Where X is the number of taken branches due to interrupt
+	 * skid. Skid is large.
+	 *
+	 * Where Y is the occurrences of the event while BRS is
+	 * capturing the lbr_nr entries.
+	 *
+	 * By using retired taken branches, we limit the impact on the
+	 * Y variable. We know it cannot be more than the depth of
+	 * BRS.
+	 */
+	if (!amd_is_brs_event(event))
+		return -EINVAL;
+
+	/*
+	 * BRS implementation does not work with frequency mode
+	 * reprogramming of the period.
+	 */
+	if (event->attr.freq)
+		return -EINVAL;
+	/*
+	 * The kernel subtracts BRS depth from period, so it must
+	 * be big enough.
+	 */
+	if (event->attr.sample_period <= x86_pmu.lbr_nr)
+		return -EINVAL;
+
+	/*
+	 * Check if we can allow PERF_SAMPLE_BRANCH_STACK
+	 */
+	ret = amd_brs_setup_filter(event);
+
+	/* only set in case of success */
+	if (!ret)
+		event->hw.flags |= PERF_X86_EVENT_AMD_BRS;
+
+	return ret;
+}
+
+/* tos = top of stack, i.e., last valid entry written */
+static inline int amd_brs_get_tos(union amd_debug_extn_cfg *cfg)
+{
+	/*
+	 * msroff: index of next entry to write so top-of-stack is one off
+	 * if BRS is full then msroff is set back to 0.
+	 */
+	return (cfg->msroff ? cfg->msroff : x86_pmu.lbr_nr) - 1;
+}
+
+/*
+ * make sure we have a sane BRS offset to begin with
+ * especially with kexec
+ */
+void amd_brs_reset(void)
+{
+	if (!cpu_feature_enabled(X86_FEATURE_BRS))
+		return;
+
+	/*
+	 * Reset config
+	 */
+	set_debug_extn_cfg(0);
+
+	/*
+	 * Mark first entry as poisoned
+	 */
+	wrmsrq(brs_to(0), BRS_POISON);
+}
+
+int __init amd_brs_init(void)
+{
+	if (!amd_brs_detect())
+		return -EOPNOTSUPP;
+
+	pr_cont("%d-deep BRS, ", x86_pmu.lbr_nr);
+
+	return 0;
+}
+
+void amd_brs_enable(void)
+{
+	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
+	union amd_debug_extn_cfg cfg;
+
+	/* Activate only on first user */
+	if (++cpuc->brs_active > 1)
+		return;
+
+	cfg.val    = 0; /* reset all fields */
+	cfg.brsmen = 1; /* enable branch sampling */
+
+	/* Set enable bit */
+	set_debug_extn_cfg(cfg.val);
+}
+
+void amd_brs_enable_all(void)
+{
+	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
+	if (cpuc->lbr_users)
+		amd_brs_enable();
+}
+
+void amd_brs_disable(void)
+{
+	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
+	union amd_debug_extn_cfg cfg;
+
+	/* Check if active (could be disabled via x86_pmu_disable_all()) */
+	if (!cpuc->brs_active)
+		return;
+
+	/* Only disable for last user */
+	if (--cpuc->brs_active)
+		return;
+
+	/*
+	 * Clear the brsmen bit but preserve the others as they contain
+	 * useful state such as vb and msroff
+	 */
+	cfg.val = get_debug_extn_cfg();
+
+	/*
+	 * When coming in on interrupt and BRS is full, then hw will have
+	 * already stopped BRS, no need to issue wrmsr again
+	 */
+	if (cfg.brsmen) {
+		cfg.brsmen = 0;
+		set_debug_extn_cfg(cfg.val);
+	}
+}
+
+void amd_brs_disable_all(void)
+{
+	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
+	if (cpuc->lbr_users)
+		amd_brs_disable();
+}
+
+static bool amd_brs_match_plm(struct perf_event *event, u64 from, u64 to)
+{
+	int type = event->attr.branch_sample_type;
+	int plm_k = PERF_SAMPLE_BRANCH_KERNEL | PERF_SAMPLE_BRANCH_HV;
+	int plm_u = PERF_SAMPLE_BRANCH_USER;
+
+	if (!(type & plm_k) && (kernel_ip(to) || kernel_ip(from)))
+		return 0;
+
+	if (!(type & plm_u) && !kernel_ip(to))
+		return 0;
+
+	return 1;
+}
+
+/*
+ * Caller must ensure amd_brs_inuse() is true before calling
+ * return:
+ */
+void amd_brs_drain(void)
+{
+	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
+	struct perf_event *event = cpuc->events[0];
+	struct perf_branch_entry *br = cpuc->lbr_entries;
+	union amd_debug_extn_cfg cfg;
+	u32 i, nr = 0, num, tos, start;
+	u32 shift = 64 - boot_cpu_data.x86_virt_bits;
+
+	/*
+	 * BRS event forced on PMC0,
+	 * so check if there is an event.
+	 * It is possible to have lbr_users > 0 but the event
+	 * not yet scheduled due to long latency PMU irq
+	 */
+	if (!event)
+		goto empty;
+
+	cfg.val = get_debug_extn_cfg();
+
+	/* Sanity check [0-x86_pmu.lbr_nr] */
+	if (WARN_ON_ONCE(cfg.msroff >= x86_pmu.lbr_nr))
+		goto empty;
+
+	/* No valid branch */
+	if (cfg.vb == 0)
+		goto empty;
+
+	/*
+	 * msr.off points to next entry to be written
+	 * tos = most recent entry index = msr.off - 1
+	 * BRS register buffer saturates, so we know we have
+	 * start < tos and that we have to read from start to tos
+	 */
+	start = 0;
+	tos = amd_brs_get_tos(&cfg);
+
+	num = tos - start + 1;
+
+	/*
+	 * BRS is only one pass (saturation) from MSROFF to depth-1
+	 * MSROFF wraps to zero when buffer is full
+	 */
+	for (i = 0; i < num; i++) {
+		u32 brs_idx = tos - i;
+		u64 from, to;
+
+		rdmsrq(brs_to(brs_idx), to);
+
+		/* Entry does not belong to us (as marked by kernel) */
+		if (to == BRS_POISON)
+			break;
+
+		/*
+		 * Sign-extend SAMP_BR_TO to 64 bits, bits 61-63 are reserved.
+		 * Necessary to generate proper virtual addresses suitable for
+		 * symbolization
+		 */
+		to = (u64)(((s64)to << shift) >> shift);
+
+		rdmsrq(brs_from(brs_idx), from);
+
+		if (!amd_brs_match_plm(event, from, to))
+			continue;
+
+		perf_clear_branch_entry_bitfields(br+nr);
+
+		br[nr].from = from;
+		br[nr].to   = to;
+
+		nr++;
+	}
+empty:
+	/* Record number of sampled branches */
+	cpuc->lbr_stack.nr = nr;
+}
+
+/*
+ * Poison most recent entry to prevent reuse by next task
+ * required because BRS entry are not tagged by PID
+ */
+static void amd_brs_poison_buffer(void)
+{
+	union amd_debug_extn_cfg cfg;
+	unsigned int idx;
+
+	/* Get current state */
+	cfg.val = get_debug_extn_cfg();
+
+	/* idx is most recently written entry */
+	idx = amd_brs_get_tos(&cfg);
+
+	/* Poison target of entry */
+	wrmsrq(brs_to(idx), BRS_POISON);
+}
+
+/*
+ * On context switch in, we need to make sure no samples from previous user
+ * are left in the BRS.
+ *
+ * On ctxswin, sched_in = true, called after the PMU has started
+ * On ctxswout, sched_in = false, called before the PMU is stopped
+ */
+void amd_pmu_brs_sched_task(struct perf_event_pmu_context *pmu_ctx,
+			    struct task_struct *task, bool sched_in)
+{
+	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
+
+	/* no active users */
+	if (!cpuc->lbr_users)
+		return;
+
+	/*
+	 * On context switch in, we need to ensure we do not use entries
+	 * from previous BRS user on that CPU, so we poison the buffer as
+	 * a faster way compared to resetting all entries.
+	 */
+	if (sched_in)
+		amd_brs_poison_buffer();
+}
+
+/*
+ * called from ACPI processor_idle.c or acpi_pad.c
+ * with interrupts disabled
+ */
+void noinstr perf_amd_brs_lopwr_cb(bool lopwr_in)
+{
+	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
+	union amd_debug_extn_cfg cfg;
+
+	/*
+	 * on mwait in, we may end up in non C0 state.
+	 * we must disable branch sampling to avoid holding the NMI
+	 * for too long. We disable it in hardware but we
+	 * keep the state in cpuc, so we can re-enable.
+	 *
+	 * The hardware will deliver the NMI if needed when brsmen cleared
+	 */
+	if (cpuc->brs_active) {
+		cfg.val = get_debug_extn_cfg();
+		cfg.brsmen = !lopwr_in;
+		set_debug_extn_cfg(cfg.val);
+	}
+}
+
+DEFINE_STATIC_CALL_NULL(perf_lopwr_cb, perf_amd_brs_lopwr_cb);
+EXPORT_STATIC_CALL_TRAMP_GPL(perf_lopwr_cb);
+
+void __init amd_brs_lopwr_init(void)
+{
+	static_call_update(perf_lopwr_cb, perf_amd_brs_lopwr_cb);
+}

linux-7.2.3/arch/x86/events/amd/iommu.c

@@ -0,0 +1,491 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2013 Advanced Micro Devices, Inc.
+ *
+ * Author: Steven Kinney <Steven.Kinney@amd.com>
+ * Author: Suravee Suthikulpanit <Suraveee.Suthikulpanit@amd.com>
+ *
+ * Perf: amd_iommu - AMD IOMMU Performance Counter PMU implementation
+ */
+
+#define pr_fmt(fmt)	"perf/amd_iommu: " fmt
+
+#include <linux/perf_event.h>
+#include <linux/init.h>
+#include <linux/cpumask.h>
+#include <linux/slab.h>
+#include <linux/amd-iommu.h>
+
+#include <asm/msr.h>
+
+#include "../perf_event.h"
+#include "iommu.h"
+
+/* iommu pmu conf masks */
+#define GET_CSOURCE(x)     ((x)->conf & 0xFFULL)
+#define GET_DEVID(x)       (((x)->conf >> 8)  & 0xFFFFULL)
+#define GET_DOMID(x)       (((x)->conf >> 24) & 0xFFFFULL)
+#define GET_PASID(x)       (((x)->conf >> 40) & 0xFFFFFULL)
+
+/* iommu pmu conf1 masks */
+#define GET_DEVID_MASK(x)  ((x)->conf1  & 0xFFFFULL)
+#define GET_DOMID_MASK(x)  (((x)->conf1 >> 16) & 0xFFFFULL)
+#define GET_PASID_MASK(x)  (((x)->conf1 >> 32) & 0xFFFFFULL)
+
+#define IOMMU_NAME_SIZE 24
+
+struct perf_amd_iommu {
+	struct list_head list;
+	struct pmu pmu;
+	struct amd_iommu *iommu;
+	char name[IOMMU_NAME_SIZE];
+	u8 max_banks;
+	u8 max_counters;
+	u64 cntr_assign_mask;
+	raw_spinlock_t lock;
+};
+
+static LIST_HEAD(perf_amd_iommu_list);
+
+/*---------------------------------------------
+ * sysfs format attributes
+ *---------------------------------------------*/
+PMU_FORMAT_ATTR(csource,    "config:0-7");
+PMU_FORMAT_ATTR(devid,      "config:8-23");
+PMU_FORMAT_ATTR(domid,      "config:24-39");
+PMU_FORMAT_ATTR(pasid,      "config:40-59");
+PMU_FORMAT_ATTR(devid_mask, "config1:0-15");
+PMU_FORMAT_ATTR(domid_mask, "config1:16-31");
+PMU_FORMAT_ATTR(pasid_mask, "config1:32-51");
+
+static struct attribute *iommu_format_attrs[] = {
+	&format_attr_csource.attr,
+	&format_attr_devid.attr,
+	&format_attr_pasid.attr,
+	&format_attr_domid.attr,
+	&format_attr_devid_mask.attr,
+	&format_attr_pasid_mask.attr,
+	&format_attr_domid_mask.attr,
+	NULL,
+};
+
+static struct attribute_group amd_iommu_format_group = {
+	.name = "format",
+	.attrs = iommu_format_attrs,
+};
+
+/*---------------------------------------------
+ * sysfs events attributes
+ *---------------------------------------------*/
+static struct attribute_group amd_iommu_events_group = {
+	.name = "events",
+};
+
+struct amd_iommu_event_desc {
+	struct device_attribute attr;
+	const char *event;
+};
+
+static ssize_t _iommu_event_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct amd_iommu_event_desc *event =
+		container_of(attr, struct amd_iommu_event_desc, attr);
+	return sprintf(buf, "%s\n", event->event);
+}
+
+#define AMD_IOMMU_EVENT_DESC(_name, _event)			\
+{								\
+	.attr  = __ATTR(_name, 0444, _iommu_event_show, NULL),	\
+	.event = _event,					\
+}
+
+static struct amd_iommu_event_desc amd_iommu_v2_event_descs[] = {
+	AMD_IOMMU_EVENT_DESC(mem_pass_untrans,        "csource=0x01"),
+	AMD_IOMMU_EVENT_DESC(mem_pass_pretrans,       "csource=0x02"),
+	AMD_IOMMU_EVENT_DESC(mem_pass_excl,           "csource=0x03"),
+	AMD_IOMMU_EVENT_DESC(mem_target_abort,        "csource=0x04"),
+	AMD_IOMMU_EVENT_DESC(mem_trans_total,         "csource=0x05"),
+	AMD_IOMMU_EVENT_DESC(mem_iommu_tlb_pte_hit,   "csource=0x06"),
+	AMD_IOMMU_EVENT_DESC(mem_iommu_tlb_pte_mis,   "csource=0x07"),
+	AMD_IOMMU_EVENT_DESC(mem_iommu_tlb_pde_hit,   "csource=0x08"),
+	AMD_IOMMU_EVENT_DESC(mem_iommu_tlb_pde_mis,   "csource=0x09"),
+	AMD_IOMMU_EVENT_DESC(mem_dte_hit,             "csource=0x0a"),
+	AMD_IOMMU_EVENT_DESC(mem_dte_mis,             "csource=0x0b"),
+	AMD_IOMMU_EVENT_DESC(page_tbl_read_tot,       "csource=0x0c"),
+	AMD_IOMMU_EVENT_DESC(page_tbl_read_nst,       "csource=0x0d"),
+	AMD_IOMMU_EVENT_DESC(page_tbl_read_gst,       "csource=0x0e"),
+	AMD_IOMMU_EVENT_DESC(int_dte_hit,             "csource=0x0f"),
+	AMD_IOMMU_EVENT_DESC(int_dte_mis,             "csource=0x10"),
+	AMD_IOMMU_EVENT_DESC(cmd_processed,           "csource=0x11"),
+	AMD_IOMMU_EVENT_DESC(cmd_processed_inv,       "csource=0x12"),
+	AMD_IOMMU_EVENT_DESC(tlb_inv,                 "csource=0x13"),
+	AMD_IOMMU_EVENT_DESC(ign_rd_wr_mmio_1ff8h,    "csource=0x14"),
+	AMD_IOMMU_EVENT_DESC(vapic_int_non_guest,     "csource=0x15"),
+	AMD_IOMMU_EVENT_DESC(vapic_int_guest,         "csource=0x16"),
+	AMD_IOMMU_EVENT_DESC(smi_recv,                "csource=0x17"),
+	AMD_IOMMU_EVENT_DESC(smi_blk,                 "csource=0x18"),
+	{ /* end: all zeroes */ },
+};
+
+/*---------------------------------------------
+ * sysfs cpumask attributes
+ *---------------------------------------------*/
+static cpumask_t iommu_cpumask;
+
+static ssize_t _iommu_cpumask_show(struct device *dev,
+				   struct device_attribute *attr,
+				   char *buf)
+{
+	return cpumap_print_to_pagebuf(true, buf, &iommu_cpumask);
+}
+static DEVICE_ATTR(cpumask, S_IRUGO, _iommu_cpumask_show, NULL);
+
+static struct attribute *iommu_cpumask_attrs[] = {
+	&dev_attr_cpumask.attr,
+	NULL,
+};
+
+static struct attribute_group amd_iommu_cpumask_group = {
+	.attrs = iommu_cpumask_attrs,
+};
+
+/*---------------------------------------------*/
+
+static int get_next_avail_iommu_bnk_cntr(struct perf_event *event)
+{
+	struct perf_amd_iommu *piommu = container_of(event->pmu, struct perf_amd_iommu, pmu);
+	int max_cntrs = piommu->max_counters;
+	int max_banks = piommu->max_banks;
+	u32 shift, bank, cntr;
+	unsigned long flags;
+	int retval;
+
+	raw_spin_lock_irqsave(&piommu->lock, flags);
+
+	for (bank = 0; bank < max_banks; bank++) {
+		for (cntr = 0; cntr < max_cntrs; cntr++) {
+			shift = bank + (bank*3) + cntr;
+			if (piommu->cntr_assign_mask & BIT_ULL(shift)) {
+				continue;
+			} else {
+				piommu->cntr_assign_mask |= BIT_ULL(shift);
+				event->hw.iommu_bank = bank;
+				event->hw.iommu_cntr = cntr;
+				retval = 0;
+				goto out;
+			}
+		}
+	}
+	retval = -ENOSPC;
+out:
+	raw_spin_unlock_irqrestore(&piommu->lock, flags);
+	return retval;
+}
+
+static int clear_avail_iommu_bnk_cntr(struct perf_amd_iommu *perf_iommu,
+					u8 bank, u8 cntr)
+{
+	unsigned long flags;
+	int max_banks, max_cntrs;
+	int shift = 0;
+
+	max_banks = perf_iommu->max_banks;
+	max_cntrs = perf_iommu->max_counters;
+
+	if ((bank > max_banks) || (cntr > max_cntrs))
+		return -EINVAL;
+
+	shift = bank + cntr + (bank*3);
+
+	raw_spin_lock_irqsave(&perf_iommu->lock, flags);
+	perf_iommu->cntr_assign_mask &= ~(1ULL<<shift);
+	raw_spin_unlock_irqrestore(&perf_iommu->lock, flags);
+
+	return 0;
+}
+
+static int perf_iommu_event_init(struct perf_event *event)
+{
+	struct hw_perf_event *hwc = &event->hw;
+
+	/* test the event attr type check for PMU enumeration */
+	if (event->attr.type != event->pmu->type)
+		return -ENOENT;
+
+	/*
+	 * IOMMU counters are shared across all cores.
+	 * Therefore, it does not support per-process mode.
+	 * Also, it does not support event sampling mode.
+	 */
+	if (is_sampling_event(event) || event->attach_state & PERF_ATTACH_TASK)
+		return -EINVAL;
+
+	if (event->cpu < 0)
+		return -EINVAL;
+
+	/* update the hw_perf_event struct with the iommu config data */
+	hwc->conf  = event->attr.config;
+	hwc->conf1 = event->attr.config1;
+
+	return 0;
+}
+
+static inline struct amd_iommu *perf_event_2_iommu(struct perf_event *ev)
+{
+	return (container_of(ev->pmu, struct perf_amd_iommu, pmu))->iommu;
+}
+
+static void perf_iommu_enable_event(struct perf_event *ev)
+{
+	struct amd_iommu *iommu = perf_event_2_iommu(ev);
+	struct hw_perf_event *hwc = &ev->hw;
+	u8 bank = hwc->iommu_bank;
+	u8 cntr = hwc->iommu_cntr;
+	u64 reg = 0ULL;
+
+	reg = GET_CSOURCE(hwc);
+	amd_iommu_pc_set_reg(iommu, bank, cntr, IOMMU_PC_COUNTER_SRC_REG, &reg);
+
+	reg = GET_DEVID_MASK(hwc);
+	reg = GET_DEVID(hwc) | (reg << 32);
+	if (reg)
+		reg |= BIT(31);
+	amd_iommu_pc_set_reg(iommu, bank, cntr, IOMMU_PC_DEVID_MATCH_REG, &reg);
+
+	reg = GET_PASID_MASK(hwc);
+	reg = GET_PASID(hwc) | (reg << 32);
+	if (reg)
+		reg |= BIT(31);
+	amd_iommu_pc_set_reg(iommu, bank, cntr, IOMMU_PC_PASID_MATCH_REG, &reg);
+
+	reg = GET_DOMID_MASK(hwc);
+	reg = GET_DOMID(hwc) | (reg << 32);
+	if (reg)
+		reg |= BIT(31);
+	amd_iommu_pc_set_reg(iommu, bank, cntr, IOMMU_PC_DOMID_MATCH_REG, &reg);
+}
+
+static void perf_iommu_disable_event(struct perf_event *event)
+{
+	struct amd_iommu *iommu = perf_event_2_iommu(event);
+	struct hw_perf_event *hwc = &event->hw;
+	u64 reg = 0ULL;
+
+	amd_iommu_pc_set_reg(iommu, hwc->iommu_bank, hwc->iommu_cntr,
+			     IOMMU_PC_COUNTER_SRC_REG, &reg);
+}
+
+static void perf_iommu_start(struct perf_event *event, int flags)
+{
+	struct hw_perf_event *hwc = &event->hw;
+
+	if (WARN_ON_ONCE(!(hwc->state & PERF_HES_STOPPED)))
+		return;
+
+	WARN_ON_ONCE(!(hwc->state & PERF_HES_UPTODATE));
+	hwc->state = 0;
+
+	/*
+	 * To account for power-gating, which prevents write to
+	 * the counter, we need to enable the counter
+	 * before setting up counter register.
+	 */
+	perf_iommu_enable_event(event);
+
+	if (flags & PERF_EF_RELOAD) {
+		u64 count = 0;
+		struct amd_iommu *iommu = perf_event_2_iommu(event);
+
+		/*
+		 * Since the IOMMU PMU only support counting mode,
+		 * the counter always start with value zero.
+		 */
+		amd_iommu_pc_set_reg(iommu, hwc->iommu_bank, hwc->iommu_cntr,
+				     IOMMU_PC_COUNTER_REG, &count);
+	}
+
+	perf_event_update_userpage(event);
+}
+
+static void perf_iommu_read(struct perf_event *event)
+{
+	u64 count;
+	struct hw_perf_event *hwc = &event->hw;
+	struct amd_iommu *iommu = perf_event_2_iommu(event);
+
+	if (amd_iommu_pc_get_reg(iommu, hwc->iommu_bank, hwc->iommu_cntr,
+				 IOMMU_PC_COUNTER_REG, &count))
+		return;
+
+	/* IOMMU pc counter register is only 48 bits */
+	count &= GENMASK_ULL(47, 0);
+
+	/*
+	 * Since the counter always start with value zero,
+	 * simply just accumulate the count for the event.
+	 */
+	local64_add(count, &event->count);
+}
+
+static void perf_iommu_stop(struct perf_event *event, int flags)
+{
+	struct hw_perf_event *hwc = &event->hw;
+
+	if (hwc->state & PERF_HES_UPTODATE)
+		return;
+
+	/*
+	 * To account for power-gating, in which reading the counter would
+	 * return zero, we need to read the register before disabling.
+	 */
+	perf_iommu_read(event);
+	hwc->state |= PERF_HES_UPTODATE;
+
+	perf_iommu_disable_event(event);
+	WARN_ON_ONCE(hwc->state & PERF_HES_STOPPED);
+	hwc->state |= PERF_HES_STOPPED;
+}
+
+static int perf_iommu_add(struct perf_event *event, int flags)
+{
+	int retval;
+
+	event->hw.state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
+
+	/* request an iommu bank/counter */
+	retval = get_next_avail_iommu_bnk_cntr(event);
+	if (retval)
+		return retval;
+
+	if (flags & PERF_EF_START)
+		perf_iommu_start(event, PERF_EF_RELOAD);
+
+	return 0;
+}
+
+static void perf_iommu_del(struct perf_event *event, int flags)
+{
+	struct hw_perf_event *hwc = &event->hw;
+	struct perf_amd_iommu *perf_iommu =
+			container_of(event->pmu, struct perf_amd_iommu, pmu);
+
+	perf_iommu_stop(event, PERF_EF_UPDATE);
+
+	/* clear the assigned iommu bank/counter */
+	clear_avail_iommu_bnk_cntr(perf_iommu,
+				   hwc->iommu_bank, hwc->iommu_cntr);
+
+	perf_event_update_userpage(event);
+}
+
+static __init int _init_events_attrs(void)
+{
+	int i = 0, j;
+	struct attribute **attrs;
+
+	while (amd_iommu_v2_event_descs[i].attr.attr.name)
+		i++;
+
+	attrs = kzalloc_objs(*attrs, i + 1);
+	if (!attrs)
+		return -ENOMEM;
+
+	for (j = 0; j < i; j++)
+		attrs[j] = &amd_iommu_v2_event_descs[j].attr.attr;
+
+	amd_iommu_events_group.attrs = attrs;
+	return 0;
+}
+
+static const struct attribute_group *amd_iommu_attr_groups[] = {
+	&amd_iommu_format_group,
+	&amd_iommu_cpumask_group,
+	&amd_iommu_events_group,
+	NULL,
+};
+
+static const struct pmu iommu_pmu __initconst = {
+	.event_init	= perf_iommu_event_init,
+	.add		= perf_iommu_add,
+	.del		= perf_iommu_del,
+	.start		= perf_iommu_start,
+	.stop		= perf_iommu_stop,
+	.read		= perf_iommu_read,
+	.task_ctx_nr	= perf_invalid_context,
+	.attr_groups	= amd_iommu_attr_groups,
+	.capabilities	= PERF_PMU_CAP_NO_EXCLUDE,
+};
+
+static __init int init_one_iommu(unsigned int idx)
+{
+	struct perf_amd_iommu *perf_iommu;
+	int ret;
+
+	perf_iommu = kzalloc_obj(struct perf_amd_iommu);
+	if (!perf_iommu)
+		return -ENOMEM;
+
+	raw_spin_lock_init(&perf_iommu->lock);
+
+	perf_iommu->pmu          = iommu_pmu;
+	perf_iommu->iommu        = get_amd_iommu(idx);
+	perf_iommu->max_banks    = amd_iommu_pc_get_max_banks(idx);
+	perf_iommu->max_counters = amd_iommu_pc_get_max_counters(idx);
+
+	if (!perf_iommu->iommu ||
+	    !perf_iommu->max_banks ||
+	    !perf_iommu->max_counters) {
+		kfree(perf_iommu);
+		return -EINVAL;
+	}
+
+	snprintf(perf_iommu->name, IOMMU_NAME_SIZE, "amd_iommu_%u", idx);
+
+	ret = perf_pmu_register(&perf_iommu->pmu, perf_iommu->name, -1);
+	if (!ret) {
+		pr_info("Detected AMD IOMMU #%d (%d banks, %d counters/bank).\n",
+			idx, perf_iommu->max_banks, perf_iommu->max_counters);
+		list_add_tail(&perf_iommu->list, &perf_amd_iommu_list);
+	} else {
+		pr_warn("Error initializing IOMMU %d.\n", idx);
+		kfree(perf_iommu);
+	}
+	return ret;
+}
+
+static __init int amd_iommu_pc_init(void)
+{
+	unsigned int i, cnt = 0;
+	int ret;
+
+	/* Make sure the IOMMU PC resource is available */
+	if (!amd_iommu_pc_supported())
+		return -ENODEV;
+
+	ret = _init_events_attrs();
+	if (ret)
+		return ret;
+
+	/*
+	 * An IOMMU PMU is specific to an IOMMU, and can function independently.
+	 * So we go through all IOMMUs and ignore the one that fails init
+	 * unless all IOMMU are failing.
+	 */
+	for (i = 0; i < amd_iommu_get_num_iommus(); i++) {
+		ret = init_one_iommu(i);
+		if (!ret)
+			cnt++;
+	}
+
+	if (!cnt) {
+		kfree(amd_iommu_events_group.attrs);
+		return -ENODEV;
+	}
+
+	/* Init cpumask attributes to only core 0 */
+	cpumask_set_cpu(0, &iommu_cpumask);
+	return 0;
+}
+
+device_initcall(amd_iommu_pc_init);

linux-7.2.3/arch/x86/events/amd/iommu.h

@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2013 Advanced Micro Devices, Inc.
+ *
+ * Author: Steven Kinney <Steven.Kinney@amd.com>
+ * Author: Suravee Suthikulpanit <Suraveee.Suthikulpanit@amd.com>
+ */
+
+#ifndef _PERF_EVENT_AMD_IOMMU_H_
+#define _PERF_EVENT_AMD_IOMMU_H_
+
+/* iommu pc mmio region register indexes */
+#define IOMMU_PC_COUNTER_REG			0x00
+#define IOMMU_PC_COUNTER_SRC_REG		0x08
+#define IOMMU_PC_PASID_MATCH_REG		0x10
+#define IOMMU_PC_DOMID_MATCH_REG		0x18
+#define IOMMU_PC_DEVID_MATCH_REG		0x20
+#define IOMMU_PC_COUNTER_REPORT_REG		0x28
+
+/* maximum specified bank/counters */
+#define PC_MAX_SPEC_BNKS			64
+#define PC_MAX_SPEC_CNTRS			16
+
+#endif /*_PERF_EVENT_AMD_IOMMU_H_*/

linux-7.2.3/arch/x86/events/amd/lbr.c

@@ -0,0 +1,439 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/perf_event.h>
+
+#include <asm/cpuid/api.h>
+#include <asm/msr.h>
+#include <asm/perf_event.h>
+
+#include "../perf_event.h"
+
+/* LBR Branch Select valid bits */
+#define LBR_SELECT_MASK		0x1ff
+
+/*
+ * LBR Branch Select filter bits which when set, ensures that the
+ * corresponding type of branches are not recorded
+ */
+#define LBR_SELECT_KERNEL		0	/* Branches ending in CPL = 0 */
+#define LBR_SELECT_USER			1	/* Branches ending in CPL > 0 */
+#define LBR_SELECT_JCC			2	/* Conditional branches */
+#define LBR_SELECT_CALL_NEAR_REL	3	/* Near relative calls */
+#define LBR_SELECT_CALL_NEAR_IND	4	/* Indirect relative calls */
+#define LBR_SELECT_RET_NEAR		5	/* Near returns */
+#define LBR_SELECT_JMP_NEAR_IND		6	/* Near indirect jumps (excl. calls and returns) */
+#define LBR_SELECT_JMP_NEAR_REL		7	/* Near relative jumps (excl. calls) */
+#define LBR_SELECT_FAR_BRANCH		8	/* Far branches */
+
+#define LBR_KERNEL	BIT(LBR_SELECT_KERNEL)
+#define LBR_USER	BIT(LBR_SELECT_USER)
+#define LBR_JCC		BIT(LBR_SELECT_JCC)
+#define LBR_REL_CALL	BIT(LBR_SELECT_CALL_NEAR_REL)
+#define LBR_IND_CALL	BIT(LBR_SELECT_CALL_NEAR_IND)
+#define LBR_RETURN	BIT(LBR_SELECT_RET_NEAR)
+#define LBR_REL_JMP	BIT(LBR_SELECT_JMP_NEAR_REL)
+#define LBR_IND_JMP	BIT(LBR_SELECT_JMP_NEAR_IND)
+#define LBR_FAR		BIT(LBR_SELECT_FAR_BRANCH)
+#define LBR_NOT_SUPP	-1	/* unsupported filter */
+#define LBR_IGNORE	0
+
+#define LBR_ANY		\
+	(LBR_JCC | LBR_REL_CALL | LBR_IND_CALL | LBR_RETURN |	\
+	 LBR_REL_JMP | LBR_IND_JMP | LBR_FAR)
+
+struct branch_entry {
+	union {
+		struct {
+			u64	ip:58;
+			u64	ip_sign_ext:5;
+			u64	mispredict:1;
+		} split;
+		u64		full;
+	} from;
+
+	union {
+		struct {
+			u64	ip:58;
+			u64	ip_sign_ext:3;
+			u64	reserved:1;
+			u64	spec:1;
+			u64	valid:1;
+		} split;
+		u64		full;
+	} to;
+};
+
+static __always_inline void amd_pmu_lbr_set_from(unsigned int idx, u64 val)
+{
+	wrmsrq(MSR_AMD_SAMP_BR_FROM + idx * 2, val);
+}
+
+static __always_inline void amd_pmu_lbr_set_to(unsigned int idx, u64 val)
+{
+	wrmsrq(MSR_AMD_SAMP_BR_FROM + idx * 2 + 1, val);
+}
+
+static __always_inline u64 amd_pmu_lbr_get_from(unsigned int idx)
+{
+	u64 val;
+
+	rdmsrq(MSR_AMD_SAMP_BR_FROM + idx * 2, val);
+
+	return val;
+}
+
+static __always_inline u64 amd_pmu_lbr_get_to(unsigned int idx)
+{
+	u64 val;
+
+	rdmsrq(MSR_AMD_SAMP_BR_FROM + idx * 2 + 1, val);
+
+	return val;
+}
+
+static __always_inline u64 sign_ext_branch_ip(u64 ip)
+{
+	u32 shift = 64 - boot_cpu_data.x86_virt_bits;
+
+	return (u64)(((s64)ip << shift) >> shift);
+}
+
+static void amd_pmu_lbr_filter(void)
+{
+	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
+	int br_sel = cpuc->br_sel, offset, type, i, j;
+	bool compress = false;
+	bool fused_only = false;
+	u64 from, to;
+
+	/* If sampling all branches, there is nothing to filter */
+	if (((br_sel & X86_BR_ALL) == X86_BR_ALL) &&
+	    ((br_sel & X86_BR_TYPE_SAVE) != X86_BR_TYPE_SAVE))
+		fused_only = true;
+
+	for (i = 0; i < cpuc->lbr_stack.nr; i++) {
+		from = cpuc->lbr_entries[i].from;
+		to = cpuc->lbr_entries[i].to;
+		type = branch_type_fused(from, to, 0, &offset);
+
+		/*
+		 * Adjust the branch from address in case of instruction
+		 * fusion where it points to an instruction preceding the
+		 * actual branch
+		 */
+		if (offset) {
+			cpuc->lbr_entries[i].from += offset;
+			if (fused_only)
+				continue;
+		}
+
+		/* If type does not correspond, then discard */
+		if (type == X86_BR_NONE || (br_sel & type) != type ||
+		    (!(br_sel & X86_BR_KERNEL) && kernel_ip(cpuc->lbr_entries[i].from))) {
+			cpuc->lbr_entries[i].from = 0;	/* mark invalid */
+			compress = true;
+		}
+
+		if ((br_sel & X86_BR_TYPE_SAVE) == X86_BR_TYPE_SAVE)
+			cpuc->lbr_entries[i].type = common_branch_type(type);
+	}
+
+	if (!compress)
+		return;
+
+	/* Remove all invalid entries */
+	for (i = 0; i < cpuc->lbr_stack.nr; ) {
+		if (!cpuc->lbr_entries[i].from) {
+			j = i;
+			while (++j < cpuc->lbr_stack.nr)
+				cpuc->lbr_entries[j - 1] = cpuc->lbr_entries[j];
+			cpuc->lbr_stack.nr--;
+			if (!cpuc->lbr_entries[i].from)
+				continue;
+		}
+		i++;
+	}
+}
+
+static const int lbr_spec_map[PERF_BR_SPEC_MAX] = {
+	PERF_BR_SPEC_NA,
+	PERF_BR_SPEC_WRONG_PATH,
+	PERF_BR_NON_SPEC_CORRECT_PATH,
+	PERF_BR_SPEC_CORRECT_PATH,
+};
+
+void amd_pmu_lbr_read(void)
+{
+	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
+	struct perf_branch_entry *br = cpuc->lbr_entries;
+	struct branch_entry entry;
+	int out = 0, idx, i;
+
+	if (!cpuc->lbr_users)
+		return;
+
+	for (i = 0; i < x86_pmu.lbr_nr; i++) {
+		entry.from.full	= amd_pmu_lbr_get_from(i);
+		entry.to.full	= amd_pmu_lbr_get_to(i);
+
+		/*
+		 * Check if a branch has been logged; if valid = 0, spec = 0
+		 * then no branch was recorded; if reserved = 1 then an
+		 * erroneous branch was recorded (see Erratum 1452)
+		 */
+		if ((!entry.to.split.valid && !entry.to.split.spec) ||
+		    entry.to.split.reserved)
+			continue;
+
+		perf_clear_branch_entry_bitfields(br + out);
+
+		br[out].from	= sign_ext_branch_ip(entry.from.split.ip);
+		br[out].to	= sign_ext_branch_ip(entry.to.split.ip);
+		br[out].mispred	= entry.from.split.mispredict;
+		br[out].predicted = !br[out].mispred;
+
+		/*
+		 * Set branch speculation information using the status of
+		 * the valid and spec bits.
+		 *
+		 * When valid = 0, spec = 0, no branch was recorded and the
+		 * entry is discarded as seen above.
+		 *
+		 * When valid = 0, spec = 1, the recorded branch was
+		 * speculative but took the wrong path.
+		 *
+		 * When valid = 1, spec = 0, the recorded branch was
+		 * non-speculative but took the correct path.
+		 *
+		 * When valid = 1, spec = 1, the recorded branch was
+		 * speculative and took the correct path
+		 */
+		idx = (entry.to.split.valid << 1) | entry.to.split.spec;
+		br[out].spec = lbr_spec_map[idx];
+		out++;
+	}
+
+	cpuc->lbr_stack.nr = out;
+
+	/*
+	 * Internal register renaming always ensures that LBR From[0] and
+	 * LBR To[0] always represent the TOS
+	 */
+	cpuc->lbr_stack.hw_idx = 0;
+
+	/* Perform further software filtering */
+	amd_pmu_lbr_filter();
+}
+
+static const int lbr_select_map[PERF_SAMPLE_BRANCH_MAX_SHIFT] = {
+	[PERF_SAMPLE_BRANCH_USER_SHIFT]		= LBR_USER,
+	[PERF_SAMPLE_BRANCH_KERNEL_SHIFT]	= LBR_KERNEL,
+	[PERF_SAMPLE_BRANCH_HV_SHIFT]		= LBR_IGNORE,
+
+	[PERF_SAMPLE_BRANCH_ANY_SHIFT]		= LBR_ANY,
+	[PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT]	= LBR_REL_CALL | LBR_IND_CALL | LBR_FAR,
+	[PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT]	= LBR_RETURN | LBR_FAR,
+	[PERF_SAMPLE_BRANCH_IND_CALL_SHIFT]	= LBR_IND_CALL,
+	[PERF_SAMPLE_BRANCH_ABORT_TX_SHIFT]	= LBR_NOT_SUPP,
+	[PERF_SAMPLE_BRANCH_IN_TX_SHIFT]	= LBR_NOT_SUPP,
+	[PERF_SAMPLE_BRANCH_NO_TX_SHIFT]	= LBR_NOT_SUPP,
+	[PERF_SAMPLE_BRANCH_COND_SHIFT]		= LBR_JCC,
+
+	[PERF_SAMPLE_BRANCH_CALL_STACK_SHIFT]	= LBR_NOT_SUPP,
+	[PERF_SAMPLE_BRANCH_IND_JUMP_SHIFT]	= LBR_IND_JMP,
+	[PERF_SAMPLE_BRANCH_CALL_SHIFT]		= LBR_REL_CALL,
+
+	[PERF_SAMPLE_BRANCH_NO_FLAGS_SHIFT]	= LBR_NOT_SUPP,
+	[PERF_SAMPLE_BRANCH_NO_CYCLES_SHIFT]	= LBR_NOT_SUPP,
+};
+
+static int amd_pmu_lbr_setup_filter(struct perf_event *event)
+{
+	struct hw_perf_event_extra *reg = &event->hw.branch_reg;
+	u64 br_type = event->attr.branch_sample_type;
+	u64 mask = 0, v;
+	int i;
+
+	/* No LBR support */
+	if (!x86_pmu.lbr_nr)
+		return -EOPNOTSUPP;
+
+	if (br_type & PERF_SAMPLE_BRANCH_USER)
+		mask |= X86_BR_USER;
+
+	if (br_type & PERF_SAMPLE_BRANCH_KERNEL)
+		mask |= X86_BR_KERNEL;
+
+	/* Ignore BRANCH_HV here */
+
+	if (br_type & PERF_SAMPLE_BRANCH_ANY)
+		mask |= X86_BR_ANY;
+
+	if (br_type & PERF_SAMPLE_BRANCH_ANY_CALL)
+		mask |= X86_BR_ANY_CALL;
+
+	if (br_type & PERF_SAMPLE_BRANCH_ANY_RETURN)
+		mask |= X86_BR_RET | X86_BR_IRET | X86_BR_SYSRET;
+
+	if (br_type & PERF_SAMPLE_BRANCH_IND_CALL)
+		mask |= X86_BR_IND_CALL;
+
+	if (br_type & PERF_SAMPLE_BRANCH_COND)
+		mask |= X86_BR_JCC;
+
+	if (br_type & PERF_SAMPLE_BRANCH_IND_JUMP)
+		mask |= X86_BR_IND_JMP;
+
+	if (br_type & PERF_SAMPLE_BRANCH_CALL)
+		mask |= X86_BR_CALL | X86_BR_ZERO_CALL;
+
+	if (br_type & PERF_SAMPLE_BRANCH_TYPE_SAVE)
+		mask |= X86_BR_TYPE_SAVE;
+
+	reg->reg = mask;
+	mask = 0;
+
+	for (i = 0; i < PERF_SAMPLE_BRANCH_MAX_SHIFT; i++) {
+		if (!(br_type & BIT_ULL(i)))
+			continue;
+
+		v = lbr_select_map[i];
+		if (v == LBR_NOT_SUPP)
+			return -EOPNOTSUPP;
+
+		if (v != LBR_IGNORE)
+			mask |= v;
+	}
+
+	/* Filter bits operate in suppress mode */
+	reg->config = mask ^ LBR_SELECT_MASK;
+
+	return 0;
+}
+
+int amd_pmu_lbr_hw_config(struct perf_event *event)
+{
+	int ret = 0;
+
+	ret = amd_pmu_lbr_setup_filter(event);
+	if (!ret)
+		event->attach_state |= PERF_ATTACH_SCHED_CB;
+
+	return ret;
+}
+
+void amd_pmu_lbr_reset(void)
+{
+	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
+	int i;
+
+	if (!x86_pmu.lbr_nr)
+		return;
+
+	/* Reset all branch records individually */
+	for (i = 0; i < x86_pmu.lbr_nr; i++) {
+		amd_pmu_lbr_set_from(i, 0);
+		amd_pmu_lbr_set_to(i, 0);
+	}
+
+	cpuc->last_task_ctx = NULL;
+	cpuc->last_log_id = 0;
+	wrmsrq(MSR_AMD64_LBR_SELECT, 0);
+}
+
+void amd_pmu_lbr_add(struct perf_event *event)
+{
+	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
+	struct hw_perf_event_extra *reg = &event->hw.branch_reg;
+
+	if (!x86_pmu.lbr_nr)
+		return;
+
+	if (has_branch_stack(event)) {
+		cpuc->lbr_select = 1;
+		cpuc->lbr_sel->config = reg->config;
+		cpuc->br_sel = reg->reg;
+	}
+
+	perf_sched_cb_inc(event->pmu);
+
+	if (!cpuc->lbr_users++ && !event->total_time_running)
+		amd_pmu_lbr_reset();
+}
+
+void amd_pmu_lbr_del(struct perf_event *event)
+{
+	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
+
+	if (!x86_pmu.lbr_nr)
+		return;
+
+	if (has_branch_stack(event))
+		cpuc->lbr_select = 0;
+
+	cpuc->lbr_users--;
+	WARN_ON_ONCE(cpuc->lbr_users < 0);
+	perf_sched_cb_dec(event->pmu);
+}
+
+void amd_pmu_lbr_sched_task(struct perf_event_pmu_context *pmu_ctx,
+			    struct task_struct *task, bool sched_in)
+{
+	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
+
+	/*
+	 * A context switch can flip the address space and LBR entries are
+	 * not tagged with an identifier. Hence, branches cannot be resolved
+	 * from the old address space and the LBR records should be wiped.
+	 */
+	if (cpuc->lbr_users && sched_in)
+		amd_pmu_lbr_reset();
+}
+
+void amd_pmu_lbr_enable_all(void)
+{
+	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
+	u64 lbr_select, dbg_ctl, dbg_extn_cfg;
+
+	if (!cpuc->lbr_users || !x86_pmu.lbr_nr)
+		return;
+
+	/* Set hardware branch filter */
+	if (cpuc->lbr_select) {
+		lbr_select = cpuc->lbr_sel->config & LBR_SELECT_MASK;
+		wrmsrq(MSR_AMD64_LBR_SELECT, lbr_select);
+	}
+
+	if (cpu_feature_enabled(X86_FEATURE_AMD_LBR_PMC_FREEZE)) {
+		rdmsrq(MSR_IA32_DEBUGCTLMSR, dbg_ctl);
+		wrmsrq(MSR_IA32_DEBUGCTLMSR, dbg_ctl | DEBUGCTLMSR_FREEZE_LBRS_ON_PMI);
+	}
+
+	rdmsrq(MSR_AMD_DBG_EXTN_CFG, dbg_extn_cfg);
+	wrmsrq(MSR_AMD_DBG_EXTN_CFG, dbg_extn_cfg | DBG_EXTN_CFG_LBRV2EN);
+}
+
+void amd_pmu_lbr_disable_all(void)
+{
+	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
+
+	if (!cpuc->lbr_users || !x86_pmu.lbr_nr)
+		return;
+
+	__amd_pmu_lbr_disable();
+}
+
+__init int amd_pmu_lbr_init(void)
+{
+	union cpuid_0x80000022_ebx ebx;
+
+	if (x86_pmu.version < 2 || !boot_cpu_has(X86_FEATURE_AMD_LBR_V2))
+		return -EOPNOTSUPP;
+
+	/* Set number of entries */
+	ebx.full = cpuid_ebx(EXT_PERFMON_DEBUG_FEATURES);
+	x86_pmu.lbr_nr = ebx.split.lbr_v2_stack_sz;
+
+	pr_cont("%d-deep LBR, ", x86_pmu.lbr_nr);
+
+	return 0;
+}

linux-7.2.3/arch/x86/events/amd/power.c

@@ -0,0 +1,309 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Performance events - AMD Processor Power Reporting Mechanism
+ *
+ * Copyright (C) 2016 Advanced Micro Devices, Inc.
+ *
+ * Author: Huang Rui <ray.huang@amd.com>
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/perf_event.h>
+
+#include <asm/cpu_device_id.h>
+#include <asm/cpuid/api.h>
+#include <asm/msr.h>
+
+#include "../perf_event.h"
+
+/* Event code: LSB 8 bits, passed in attr->config any other bit is reserved. */
+#define AMD_POWER_EVENT_MASK		0xFFULL
+
+/*
+ * Accumulated power status counters.
+ */
+#define AMD_POWER_EVENTSEL_PKG		1
+
+/*
+ * The ratio of compute unit power accumulator sample period to the
+ * PTSC period.
+ */
+static unsigned int cpu_pwr_sample_ratio;
+
+/* Maximum accumulated power of a compute unit. */
+static u64 max_cu_acc_power;
+
+static struct pmu pmu_class;
+
+/*
+ * Accumulated power represents the sum of each compute unit's (CU) power
+ * consumption. On any core of each CU we read the total accumulated power from
+ * MSR_F15H_CU_PWR_ACCUMULATOR. cpu_mask represents CPU bit map of all cores
+ * which are picked to measure the power for the CUs they belong to.
+ */
+static cpumask_t cpu_mask;
+
+static void event_update(struct perf_event *event)
+{
+	struct hw_perf_event *hwc = &event->hw;
+	u64 prev_pwr_acc, new_pwr_acc, prev_ptsc, new_ptsc;
+	u64 delta, tdelta;
+
+	prev_pwr_acc = hwc->pwr_acc;
+	prev_ptsc = hwc->ptsc;
+	rdmsrq(MSR_F15H_CU_PWR_ACCUMULATOR, new_pwr_acc);
+	rdmsrq(MSR_F15H_PTSC, new_ptsc);
+
+	/*
+	 * Calculate the CU power consumption over a time period, the unit of
+	 * final value (delta) is micro-Watts. Then add it to the event count.
+	 */
+	if (new_pwr_acc < prev_pwr_acc) {
+		delta = max_cu_acc_power + new_pwr_acc;
+		delta -= prev_pwr_acc;
+	} else
+		delta = new_pwr_acc - prev_pwr_acc;
+
+	delta *= cpu_pwr_sample_ratio * 1000;
+	tdelta = new_ptsc - prev_ptsc;
+
+	do_div(delta, tdelta);
+	local64_add(delta, &event->count);
+}
+
+static void __pmu_event_start(struct perf_event *event)
+{
+	if (WARN_ON_ONCE(!(event->hw.state & PERF_HES_STOPPED)))
+		return;
+
+	event->hw.state = 0;
+
+	rdmsrq(MSR_F15H_PTSC, event->hw.ptsc);
+	rdmsrq(MSR_F15H_CU_PWR_ACCUMULATOR, event->hw.pwr_acc);
+}
+
+static void pmu_event_start(struct perf_event *event, int mode)
+{
+	__pmu_event_start(event);
+}
+
+static void pmu_event_stop(struct perf_event *event, int mode)
+{
+	struct hw_perf_event *hwc = &event->hw;
+
+	/* Mark event as deactivated and stopped. */
+	if (!(hwc->state & PERF_HES_STOPPED))
+		hwc->state |= PERF_HES_STOPPED;
+
+	/* Check if software counter update is necessary. */
+	if ((mode & PERF_EF_UPDATE) && !(hwc->state & PERF_HES_UPTODATE)) {
+		/*
+		 * Drain the remaining delta count out of an event
+		 * that we are disabling:
+		 */
+		event_update(event);
+		hwc->state |= PERF_HES_UPTODATE;
+	}
+}
+
+static int pmu_event_add(struct perf_event *event, int mode)
+{
+	struct hw_perf_event *hwc = &event->hw;
+
+	hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
+
+	if (mode & PERF_EF_START)
+		__pmu_event_start(event);
+
+	return 0;
+}
+
+static void pmu_event_del(struct perf_event *event, int flags)
+{
+	pmu_event_stop(event, PERF_EF_UPDATE);
+}
+
+static int pmu_event_init(struct perf_event *event)
+{
+	u64 cfg = event->attr.config & AMD_POWER_EVENT_MASK;
+
+	/* Only look at AMD power events. */
+	if (event->attr.type != pmu_class.type)
+		return -ENOENT;
+
+	/* Unsupported modes and filters. */
+	if (event->attr.sample_period)
+		return -EINVAL;
+
+	if (cfg != AMD_POWER_EVENTSEL_PKG)
+		return -EINVAL;
+
+	return 0;
+}
+
+static void pmu_event_read(struct perf_event *event)
+{
+	event_update(event);
+}
+
+static ssize_t
+get_attr_cpumask(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	return cpumap_print_to_pagebuf(true, buf, &cpu_mask);
+}
+
+static DEVICE_ATTR(cpumask, S_IRUGO, get_attr_cpumask, NULL);
+
+static struct attribute *pmu_attrs[] = {
+	&dev_attr_cpumask.attr,
+	NULL,
+};
+
+static struct attribute_group pmu_attr_group = {
+	.attrs = pmu_attrs,
+};
+
+/*
+ * Currently it only supports to report the power of each
+ * processor/package.
+ */
+EVENT_ATTR_STR(power-pkg, power_pkg, "event=0x01");
+
+EVENT_ATTR_STR(power-pkg.unit, power_pkg_unit, "mWatts");
+
+/* Convert the count from micro-Watts to milli-Watts. */
+EVENT_ATTR_STR(power-pkg.scale, power_pkg_scale, "1.000000e-3");
+
+static struct attribute *events_attr[] = {
+	EVENT_PTR(power_pkg),
+	EVENT_PTR(power_pkg_unit),
+	EVENT_PTR(power_pkg_scale),
+	NULL,
+};
+
+static struct attribute_group pmu_events_group = {
+	.name	= "events",
+	.attrs	= events_attr,
+};
+
+PMU_FORMAT_ATTR(event, "config:0-7");
+
+static struct attribute *formats_attr[] = {
+	&format_attr_event.attr,
+	NULL,
+};
+
+static struct attribute_group pmu_format_group = {
+	.name	= "format",
+	.attrs	= formats_attr,
+};
+
+static const struct attribute_group *attr_groups[] = {
+	&pmu_attr_group,
+	&pmu_format_group,
+	&pmu_events_group,
+	NULL,
+};
+
+static struct pmu pmu_class = {
+	.attr_groups	= attr_groups,
+	/* system-wide only */
+	.task_ctx_nr	= perf_invalid_context,
+	.event_init	= pmu_event_init,
+	.add		= pmu_event_add,
+	.del		= pmu_event_del,
+	.start		= pmu_event_start,
+	.stop		= pmu_event_stop,
+	.read		= pmu_event_read,
+	.capabilities	= PERF_PMU_CAP_NO_EXCLUDE,
+	.module		= THIS_MODULE,
+};
+
+static int power_cpu_exit(unsigned int cpu)
+{
+	int target;
+
+	if (!cpumask_test_and_clear_cpu(cpu, &cpu_mask))
+		return 0;
+
+	/*
+	 * Find a new CPU on the same compute unit, if was set in cpumask
+	 * and still some CPUs on compute unit. Then migrate event and
+	 * context to new CPU.
+	 */
+	target = cpumask_any_but(topology_sibling_cpumask(cpu), cpu);
+	if (target < nr_cpumask_bits) {
+		cpumask_set_cpu(target, &cpu_mask);
+		perf_pmu_migrate_context(&pmu_class, cpu, target);
+	}
+	return 0;
+}
+
+static int power_cpu_init(unsigned int cpu)
+{
+	int target;
+
+	/*
+	 * 1) If any CPU is set at cpu_mask in the same compute unit, do
+	 * nothing.
+	 * 2) If no CPU is set at cpu_mask in the same compute unit,
+	 * set current ONLINE CPU.
+	 *
+	 * Note: if there is a CPU aside of the new one already in the
+	 * sibling mask, then it is also in cpu_mask.
+	 */
+	target = cpumask_any_but(topology_sibling_cpumask(cpu), cpu);
+	if (target >= nr_cpumask_bits)
+		cpumask_set_cpu(cpu, &cpu_mask);
+	return 0;
+}
+
+static const struct x86_cpu_id cpu_match[] = {
+	X86_MATCH_VENDOR_FAM(AMD, 0x15, NULL),
+	{},
+};
+
+static int __init amd_power_pmu_init(void)
+{
+	int ret;
+
+	if (!x86_match_cpu(cpu_match))
+		return -ENODEV;
+
+	if (!boot_cpu_has(X86_FEATURE_ACC_POWER))
+		return -ENODEV;
+
+	cpu_pwr_sample_ratio = cpuid_ecx(0x80000007);
+
+	if (rdmsrq_safe(MSR_F15H_CU_MAX_PWR_ACCUMULATOR, &max_cu_acc_power)) {
+		pr_err("Failed to read max compute unit power accumulator MSR\n");
+		return -ENODEV;
+	}
+
+
+	cpuhp_setup_state(CPUHP_AP_PERF_X86_AMD_POWER_ONLINE,
+			  "perf/x86/amd/power:online",
+			  power_cpu_init, power_cpu_exit);
+
+	ret = perf_pmu_register(&pmu_class, "power", -1);
+	if (WARN_ON(ret)) {
+		pr_warn("AMD Power PMU registration failed\n");
+		return ret;
+	}
+
+	pr_info("AMD Power PMU detected\n");
+	return ret;
+}
+module_init(amd_power_pmu_init);
+
+static void __exit amd_power_pmu_exit(void)
+{
+	cpuhp_remove_state_nocalls(CPUHP_AP_PERF_X86_AMD_POWER_ONLINE);
+	perf_pmu_unregister(&pmu_class);
+}
+module_exit(amd_power_pmu_exit);
+
+MODULE_AUTHOR("Huang Rui <ray.huang@amd.com>");
+MODULE_DESCRIPTION("AMD Processor Power Reporting Mechanism");
+MODULE_LICENSE("GPL v2");