diff options
Diffstat (limited to 'arch/x86/xen/pmu.c')
| -rw-r--r-- | arch/x86/xen/pmu.c | 570 |
1 files changed, 570 insertions, 0 deletions
diff --git a/arch/x86/xen/pmu.c b/arch/x86/xen/pmu.c new file mode 100644 index 000000000000..724a08740a04 --- /dev/null +++ b/arch/x86/xen/pmu.c @@ -0,0 +1,570 @@ +#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 "../kernel/cpu/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; + 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: + pr_warn_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; +} |