v4.19.13 snapshot.
diff --git a/arch/x86/xen/pmu.c b/arch/x86/xen/pmu.c
new file mode 100644
index 0000000..95997e6
--- /dev/null
+++ b/arch/x86/xen/pmu.c
@@ -0,0 +1,574 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/types.h>
+#include <linux/interrupt.h>
+
+#include <asm/xen/hypercall.h>
+#include <xen/page.h>
+#include <xen/interface/xen.h>
+#include <xen/interface/vcpu.h>
+#include <xen/interface/xenpmu.h>
+
+#include "xen-ops.h"
+#include "pmu.h"
+
+/* x86_pmu.handle_irq definition */
+#include "../events/perf_event.h"
+
+#define XENPMU_IRQ_PROCESSING 1
+struct xenpmu {
+ /* Shared page between hypervisor and domain */
+ struct xen_pmu_data *xenpmu_data;
+
+ uint8_t flags;
+};
+static DEFINE_PER_CPU(struct xenpmu, xenpmu_shared);
+#define get_xenpmu_data() (this_cpu_ptr(&xenpmu_shared)->xenpmu_data)
+#define get_xenpmu_flags() (this_cpu_ptr(&xenpmu_shared)->flags)
+
+/* Macro for computing address of a PMU MSR bank */
+#define field_offset(ctxt, field) ((void *)((uintptr_t)ctxt + \
+ (uintptr_t)ctxt->field))
+
+/* AMD PMU */
+#define F15H_NUM_COUNTERS 6
+#define F10H_NUM_COUNTERS 4
+
+static __read_mostly uint32_t amd_counters_base;
+static __read_mostly uint32_t amd_ctrls_base;
+static __read_mostly int amd_msr_step;
+static __read_mostly int k7_counters_mirrored;
+static __read_mostly int amd_num_counters;
+
+/* Intel PMU */
+#define MSR_TYPE_COUNTER 0
+#define MSR_TYPE_CTRL 1
+#define MSR_TYPE_GLOBAL 2
+#define MSR_TYPE_ARCH_COUNTER 3
+#define MSR_TYPE_ARCH_CTRL 4
+
+/* Number of general pmu registers (CPUID.EAX[0xa].EAX[8..15]) */
+#define PMU_GENERAL_NR_SHIFT 8
+#define PMU_GENERAL_NR_BITS 8
+#define PMU_GENERAL_NR_MASK (((1 << PMU_GENERAL_NR_BITS) - 1) \
+ << PMU_GENERAL_NR_SHIFT)
+
+/* Number of fixed pmu registers (CPUID.EDX[0xa].EDX[0..4]) */
+#define PMU_FIXED_NR_SHIFT 0
+#define PMU_FIXED_NR_BITS 5
+#define PMU_FIXED_NR_MASK (((1 << PMU_FIXED_NR_BITS) - 1) \
+ << PMU_FIXED_NR_SHIFT)
+
+/* Alias registers (0x4c1) for full-width writes to PMCs */
+#define MSR_PMC_ALIAS_MASK (~(MSR_IA32_PERFCTR0 ^ MSR_IA32_PMC0))
+
+#define INTEL_PMC_TYPE_SHIFT 30
+
+static __read_mostly int intel_num_arch_counters, intel_num_fixed_counters;
+
+
+static void xen_pmu_arch_init(void)
+{
+ if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {
+
+ switch (boot_cpu_data.x86) {
+ case 0x15:
+ amd_num_counters = F15H_NUM_COUNTERS;
+ amd_counters_base = MSR_F15H_PERF_CTR;
+ amd_ctrls_base = MSR_F15H_PERF_CTL;
+ amd_msr_step = 2;
+ k7_counters_mirrored = 1;
+ break;
+ case 0x10:
+ case 0x12:
+ case 0x14:
+ case 0x16:
+ default:
+ amd_num_counters = F10H_NUM_COUNTERS;
+ amd_counters_base = MSR_K7_PERFCTR0;
+ amd_ctrls_base = MSR_K7_EVNTSEL0;
+ amd_msr_step = 1;
+ k7_counters_mirrored = 0;
+ break;
+ }
+ } else {
+ uint32_t eax, ebx, ecx, edx;
+
+ cpuid(0xa, &eax, &ebx, &ecx, &edx);
+
+ intel_num_arch_counters = (eax & PMU_GENERAL_NR_MASK) >>
+ PMU_GENERAL_NR_SHIFT;
+ intel_num_fixed_counters = (edx & PMU_FIXED_NR_MASK) >>
+ PMU_FIXED_NR_SHIFT;
+ }
+}
+
+static inline uint32_t get_fam15h_addr(u32 addr)
+{
+ switch (addr) {
+ case MSR_K7_PERFCTR0:
+ case MSR_K7_PERFCTR1:
+ case MSR_K7_PERFCTR2:
+ case MSR_K7_PERFCTR3:
+ return MSR_F15H_PERF_CTR + (addr - MSR_K7_PERFCTR0);
+ case MSR_K7_EVNTSEL0:
+ case MSR_K7_EVNTSEL1:
+ case MSR_K7_EVNTSEL2:
+ case MSR_K7_EVNTSEL3:
+ return MSR_F15H_PERF_CTL + (addr - MSR_K7_EVNTSEL0);
+ default:
+ break;
+ }
+
+ return addr;
+}
+
+static inline bool is_amd_pmu_msr(unsigned int msr)
+{
+ if ((msr >= MSR_F15H_PERF_CTL &&
+ msr < MSR_F15H_PERF_CTR + (amd_num_counters * 2)) ||
+ (msr >= MSR_K7_EVNTSEL0 &&
+ msr < MSR_K7_PERFCTR0 + amd_num_counters))
+ return true;
+
+ return false;
+}
+
+static int is_intel_pmu_msr(u32 msr_index, int *type, int *index)
+{
+ u32 msr_index_pmc;
+
+ switch (msr_index) {
+ case MSR_CORE_PERF_FIXED_CTR_CTRL:
+ case MSR_IA32_DS_AREA:
+ case MSR_IA32_PEBS_ENABLE:
+ *type = MSR_TYPE_CTRL;
+ return true;
+
+ case MSR_CORE_PERF_GLOBAL_CTRL:
+ case MSR_CORE_PERF_GLOBAL_STATUS:
+ case MSR_CORE_PERF_GLOBAL_OVF_CTRL:
+ *type = MSR_TYPE_GLOBAL;
+ return true;
+
+ default:
+
+ if ((msr_index >= MSR_CORE_PERF_FIXED_CTR0) &&
+ (msr_index < MSR_CORE_PERF_FIXED_CTR0 +
+ intel_num_fixed_counters)) {
+ *index = msr_index - MSR_CORE_PERF_FIXED_CTR0;
+ *type = MSR_TYPE_COUNTER;
+ return true;
+ }
+
+ if ((msr_index >= MSR_P6_EVNTSEL0) &&
+ (msr_index < MSR_P6_EVNTSEL0 + intel_num_arch_counters)) {
+ *index = msr_index - MSR_P6_EVNTSEL0;
+ *type = MSR_TYPE_ARCH_CTRL;
+ return true;
+ }
+
+ msr_index_pmc = msr_index & MSR_PMC_ALIAS_MASK;
+ if ((msr_index_pmc >= MSR_IA32_PERFCTR0) &&
+ (msr_index_pmc < MSR_IA32_PERFCTR0 +
+ intel_num_arch_counters)) {
+ *type = MSR_TYPE_ARCH_COUNTER;
+ *index = msr_index_pmc - MSR_IA32_PERFCTR0;
+ return true;
+ }
+ return false;
+ }
+}
+
+static bool xen_intel_pmu_emulate(unsigned int msr, u64 *val, int type,
+ int index, bool is_read)
+{
+ uint64_t *reg = NULL;
+ struct xen_pmu_intel_ctxt *ctxt;
+ uint64_t *fix_counters;
+ struct xen_pmu_cntr_pair *arch_cntr_pair;
+ struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
+ uint8_t xenpmu_flags = get_xenpmu_flags();
+
+
+ if (!xenpmu_data || !(xenpmu_flags & XENPMU_IRQ_PROCESSING))
+ return false;
+
+ ctxt = &xenpmu_data->pmu.c.intel;
+
+ switch (msr) {
+ case MSR_CORE_PERF_GLOBAL_OVF_CTRL:
+ reg = &ctxt->global_ovf_ctrl;
+ break;
+ case MSR_CORE_PERF_GLOBAL_STATUS:
+ reg = &ctxt->global_status;
+ break;
+ case MSR_CORE_PERF_GLOBAL_CTRL:
+ reg = &ctxt->global_ctrl;
+ break;
+ case MSR_CORE_PERF_FIXED_CTR_CTRL:
+ reg = &ctxt->fixed_ctrl;
+ break;
+ default:
+ switch (type) {
+ case MSR_TYPE_COUNTER:
+ fix_counters = field_offset(ctxt, fixed_counters);
+ reg = &fix_counters[index];
+ break;
+ case MSR_TYPE_ARCH_COUNTER:
+ arch_cntr_pair = field_offset(ctxt, arch_counters);
+ reg = &arch_cntr_pair[index].counter;
+ break;
+ case MSR_TYPE_ARCH_CTRL:
+ arch_cntr_pair = field_offset(ctxt, arch_counters);
+ reg = &arch_cntr_pair[index].control;
+ break;
+ default:
+ return false;
+ }
+ }
+
+ if (reg) {
+ if (is_read)
+ *val = *reg;
+ else {
+ *reg = *val;
+
+ if (msr == MSR_CORE_PERF_GLOBAL_OVF_CTRL)
+ ctxt->global_status &= (~(*val));
+ }
+ return true;
+ }
+
+ return false;
+}
+
+static bool xen_amd_pmu_emulate(unsigned int msr, u64 *val, bool is_read)
+{
+ uint64_t *reg = NULL;
+ int i, off = 0;
+ struct xen_pmu_amd_ctxt *ctxt;
+ uint64_t *counter_regs, *ctrl_regs;
+ struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
+ uint8_t xenpmu_flags = get_xenpmu_flags();
+
+ if (!xenpmu_data || !(xenpmu_flags & XENPMU_IRQ_PROCESSING))
+ return false;
+
+ if (k7_counters_mirrored &&
+ ((msr >= MSR_K7_EVNTSEL0) && (msr <= MSR_K7_PERFCTR3)))
+ msr = get_fam15h_addr(msr);
+
+ ctxt = &xenpmu_data->pmu.c.amd;
+ for (i = 0; i < amd_num_counters; i++) {
+ if (msr == amd_ctrls_base + off) {
+ ctrl_regs = field_offset(ctxt, ctrls);
+ reg = &ctrl_regs[i];
+ break;
+ } else if (msr == amd_counters_base + off) {
+ counter_regs = field_offset(ctxt, counters);
+ reg = &counter_regs[i];
+ break;
+ }
+ off += amd_msr_step;
+ }
+
+ if (reg) {
+ if (is_read)
+ *val = *reg;
+ else
+ *reg = *val;
+
+ return true;
+ }
+ return false;
+}
+
+bool pmu_msr_read(unsigned int msr, uint64_t *val, int *err)
+{
+ if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {
+ if (is_amd_pmu_msr(msr)) {
+ if (!xen_amd_pmu_emulate(msr, val, 1))
+ *val = native_read_msr_safe(msr, err);
+ return true;
+ }
+ } else {
+ int type, index;
+
+ if (is_intel_pmu_msr(msr, &type, &index)) {
+ if (!xen_intel_pmu_emulate(msr, val, type, index, 1))
+ *val = native_read_msr_safe(msr, err);
+ return true;
+ }
+ }
+
+ return false;
+}
+
+bool pmu_msr_write(unsigned int msr, uint32_t low, uint32_t high, int *err)
+{
+ uint64_t val = ((uint64_t)high << 32) | low;
+
+ if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {
+ if (is_amd_pmu_msr(msr)) {
+ if (!xen_amd_pmu_emulate(msr, &val, 0))
+ *err = native_write_msr_safe(msr, low, high);
+ return true;
+ }
+ } else {
+ int type, index;
+
+ if (is_intel_pmu_msr(msr, &type, &index)) {
+ if (!xen_intel_pmu_emulate(msr, &val, type, index, 0))
+ *err = native_write_msr_safe(msr, low, high);
+ return true;
+ }
+ }
+
+ return false;
+}
+
+static unsigned long long xen_amd_read_pmc(int counter)
+{
+ struct xen_pmu_amd_ctxt *ctxt;
+ uint64_t *counter_regs;
+ struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
+ uint8_t xenpmu_flags = get_xenpmu_flags();
+
+ if (!xenpmu_data || !(xenpmu_flags & XENPMU_IRQ_PROCESSING)) {
+ uint32_t msr;
+ int err;
+
+ msr = amd_counters_base + (counter * amd_msr_step);
+ return native_read_msr_safe(msr, &err);
+ }
+
+ ctxt = &xenpmu_data->pmu.c.amd;
+ counter_regs = field_offset(ctxt, counters);
+ return counter_regs[counter];
+}
+
+static unsigned long long xen_intel_read_pmc(int counter)
+{
+ struct xen_pmu_intel_ctxt *ctxt;
+ uint64_t *fixed_counters;
+ struct xen_pmu_cntr_pair *arch_cntr_pair;
+ struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
+ uint8_t xenpmu_flags = get_xenpmu_flags();
+
+ if (!xenpmu_data || !(xenpmu_flags & XENPMU_IRQ_PROCESSING)) {
+ uint32_t msr;
+ int err;
+
+ if (counter & (1 << INTEL_PMC_TYPE_SHIFT))
+ msr = MSR_CORE_PERF_FIXED_CTR0 + (counter & 0xffff);
+ else
+ msr = MSR_IA32_PERFCTR0 + counter;
+
+ return native_read_msr_safe(msr, &err);
+ }
+
+ ctxt = &xenpmu_data->pmu.c.intel;
+ if (counter & (1 << INTEL_PMC_TYPE_SHIFT)) {
+ fixed_counters = field_offset(ctxt, fixed_counters);
+ return fixed_counters[counter & 0xffff];
+ }
+
+ arch_cntr_pair = field_offset(ctxt, arch_counters);
+ return arch_cntr_pair[counter].counter;
+}
+
+unsigned long long xen_read_pmc(int counter)
+{
+ if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
+ return xen_amd_read_pmc(counter);
+ else
+ return xen_intel_read_pmc(counter);
+}
+
+int pmu_apic_update(uint32_t val)
+{
+ int ret;
+ struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
+
+ if (!xenpmu_data) {
+ pr_warn_once("%s: pmudata not initialized\n", __func__);
+ return -EINVAL;
+ }
+
+ xenpmu_data->pmu.l.lapic_lvtpc = val;
+
+ if (get_xenpmu_flags() & XENPMU_IRQ_PROCESSING)
+ return 0;
+
+ ret = HYPERVISOR_xenpmu_op(XENPMU_lvtpc_set, NULL);
+
+ return ret;
+}
+
+/* perf callbacks */
+static int xen_is_in_guest(void)
+{
+ const struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
+
+ if (!xenpmu_data) {
+ pr_warn_once("%s: pmudata not initialized\n", __func__);
+ return 0;
+ }
+
+ if (!xen_initial_domain() || (xenpmu_data->domain_id >= DOMID_SELF))
+ return 0;
+
+ return 1;
+}
+
+static int xen_is_user_mode(void)
+{
+ const struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
+
+ if (!xenpmu_data) {
+ pr_warn_once("%s: pmudata not initialized\n", __func__);
+ return 0;
+ }
+
+ if (xenpmu_data->pmu.pmu_flags & PMU_SAMPLE_PV)
+ return (xenpmu_data->pmu.pmu_flags & PMU_SAMPLE_USER);
+ else
+ return !!(xenpmu_data->pmu.r.regs.cpl & 3);
+}
+
+static unsigned long xen_get_guest_ip(void)
+{
+ const struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
+
+ if (!xenpmu_data) {
+ pr_warn_once("%s: pmudata not initialized\n", __func__);
+ return 0;
+ }
+
+ return xenpmu_data->pmu.r.regs.ip;
+}
+
+static struct perf_guest_info_callbacks xen_guest_cbs = {
+ .is_in_guest = xen_is_in_guest,
+ .is_user_mode = xen_is_user_mode,
+ .get_guest_ip = xen_get_guest_ip,
+};
+
+/* Convert registers from Xen's format to Linux' */
+static void xen_convert_regs(const struct xen_pmu_regs *xen_regs,
+ struct pt_regs *regs, uint64_t pmu_flags)
+{
+ regs->ip = xen_regs->ip;
+ regs->cs = xen_regs->cs;
+ regs->sp = xen_regs->sp;
+
+ if (pmu_flags & PMU_SAMPLE_PV) {
+ if (pmu_flags & PMU_SAMPLE_USER)
+ regs->cs |= 3;
+ else
+ regs->cs &= ~3;
+ } else {
+ if (xen_regs->cpl)
+ regs->cs |= 3;
+ else
+ regs->cs &= ~3;
+ }
+}
+
+irqreturn_t xen_pmu_irq_handler(int irq, void *dev_id)
+{
+ int err, ret = IRQ_NONE;
+ struct pt_regs regs = {0};
+ const struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
+ uint8_t xenpmu_flags = get_xenpmu_flags();
+
+ if (!xenpmu_data) {
+ pr_warn_once("%s: pmudata not initialized\n", __func__);
+ return ret;
+ }
+
+ this_cpu_ptr(&xenpmu_shared)->flags =
+ xenpmu_flags | XENPMU_IRQ_PROCESSING;
+ xen_convert_regs(&xenpmu_data->pmu.r.regs, ®s,
+ xenpmu_data->pmu.pmu_flags);
+ if (x86_pmu.handle_irq(®s))
+ ret = IRQ_HANDLED;
+
+ /* Write out cached context to HW */
+ err = HYPERVISOR_xenpmu_op(XENPMU_flush, NULL);
+ this_cpu_ptr(&xenpmu_shared)->flags = xenpmu_flags;
+ if (err) {
+ pr_warn_once("%s: failed hypercall, err: %d\n", __func__, err);
+ return IRQ_NONE;
+ }
+
+ return ret;
+}
+
+bool is_xen_pmu(int cpu)
+{
+ return (get_xenpmu_data() != NULL);
+}
+
+void xen_pmu_init(int cpu)
+{
+ int err;
+ struct xen_pmu_params xp;
+ unsigned long pfn;
+ struct xen_pmu_data *xenpmu_data;
+
+ BUILD_BUG_ON(sizeof(struct xen_pmu_data) > PAGE_SIZE);
+
+ if (xen_hvm_domain())
+ return;
+
+ xenpmu_data = (struct xen_pmu_data *)get_zeroed_page(GFP_KERNEL);
+ if (!xenpmu_data) {
+ pr_err("VPMU init: No memory\n");
+ return;
+ }
+ pfn = virt_to_pfn(xenpmu_data);
+
+ xp.val = pfn_to_mfn(pfn);
+ xp.vcpu = cpu;
+ xp.version.maj = XENPMU_VER_MAJ;
+ xp.version.min = XENPMU_VER_MIN;
+ err = HYPERVISOR_xenpmu_op(XENPMU_init, &xp);
+ if (err)
+ goto fail;
+
+ per_cpu(xenpmu_shared, cpu).xenpmu_data = xenpmu_data;
+ per_cpu(xenpmu_shared, cpu).flags = 0;
+
+ if (cpu == 0) {
+ perf_register_guest_info_callbacks(&xen_guest_cbs);
+ xen_pmu_arch_init();
+ }
+
+ return;
+
+fail:
+ if (err == -EOPNOTSUPP || err == -ENOSYS)
+ pr_info_once("VPMU disabled by hypervisor.\n");
+ else
+ pr_info_once("Could not initialize VPMU for cpu %d, error %d\n",
+ cpu, err);
+ free_pages((unsigned long)xenpmu_data, 0);
+}
+
+void xen_pmu_finish(int cpu)
+{
+ struct xen_pmu_params xp;
+
+ if (xen_hvm_domain())
+ return;
+
+ xp.vcpu = cpu;
+ xp.version.maj = XENPMU_VER_MAJ;
+ xp.version.min = XENPMU_VER_MIN;
+
+ (void)HYPERVISOR_xenpmu_op(XENPMU_finish, &xp);
+
+ free_pages((unsigned long)per_cpu(xenpmu_shared, cpu).xenpmu_data, 0);
+ per_cpu(xenpmu_shared, cpu).xenpmu_data = NULL;
+}