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v6.2
  1// SPDX-License-Identifier: GPL-2.0
  2#include <linux/types.h>
  3#include <linux/interrupt.h>
  4
  5#include <asm/xen/hypercall.h>
  6#include <xen/xen.h>
  7#include <xen/page.h>
  8#include <xen/interface/xen.h>
  9#include <xen/interface/vcpu.h>
 10#include <xen/interface/xenpmu.h>
 11
 12#include "xen-ops.h"
 13#include "pmu.h"
 14
 15/* x86_pmu.handle_irq definition */
 16#include "../events/perf_event.h"
 17
 18#define XENPMU_IRQ_PROCESSING    1
 19struct xenpmu {
 20	/* Shared page between hypervisor and domain */
 21	struct xen_pmu_data *xenpmu_data;
 22
 23	uint8_t flags;
 24};
 25static DEFINE_PER_CPU(struct xenpmu, xenpmu_shared);
 26#define get_xenpmu_data()    (this_cpu_ptr(&xenpmu_shared)->xenpmu_data)
 27#define get_xenpmu_flags()   (this_cpu_ptr(&xenpmu_shared)->flags)
 28
 29/* Macro for computing address of a PMU MSR bank */
 30#define field_offset(ctxt, field) ((void *)((uintptr_t)ctxt + \
 31					    (uintptr_t)ctxt->field))
 32
 33/* AMD PMU */
 34#define F15H_NUM_COUNTERS   6
 35#define F10H_NUM_COUNTERS   4
 36
 37static __read_mostly uint32_t amd_counters_base;
 38static __read_mostly uint32_t amd_ctrls_base;
 39static __read_mostly int amd_msr_step;
 40static __read_mostly int k7_counters_mirrored;
 41static __read_mostly int amd_num_counters;
 42
 43/* Intel PMU */
 44#define MSR_TYPE_COUNTER            0
 45#define MSR_TYPE_CTRL               1
 46#define MSR_TYPE_GLOBAL             2
 47#define MSR_TYPE_ARCH_COUNTER       3
 48#define MSR_TYPE_ARCH_CTRL          4
 49
 50/* Number of general pmu registers (CPUID.EAX[0xa].EAX[8..15]) */
 51#define PMU_GENERAL_NR_SHIFT        8
 52#define PMU_GENERAL_NR_BITS         8
 53#define PMU_GENERAL_NR_MASK         (((1 << PMU_GENERAL_NR_BITS) - 1) \
 54				     << PMU_GENERAL_NR_SHIFT)
 55
 56/* Number of fixed pmu registers (CPUID.EDX[0xa].EDX[0..4]) */
 57#define PMU_FIXED_NR_SHIFT          0
 58#define PMU_FIXED_NR_BITS           5
 59#define PMU_FIXED_NR_MASK           (((1 << PMU_FIXED_NR_BITS) - 1) \
 60				     << PMU_FIXED_NR_SHIFT)
 61
 62/* Alias registers (0x4c1) for full-width writes to PMCs */
 63#define MSR_PMC_ALIAS_MASK          (~(MSR_IA32_PERFCTR0 ^ MSR_IA32_PMC0))
 64
 65#define INTEL_PMC_TYPE_SHIFT        30
 66
 67static __read_mostly int intel_num_arch_counters, intel_num_fixed_counters;
 68
 69
 70static void xen_pmu_arch_init(void)
 71{
 72	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {
 73
 74		switch (boot_cpu_data.x86) {
 75		case 0x15:
 76			amd_num_counters = F15H_NUM_COUNTERS;
 77			amd_counters_base = MSR_F15H_PERF_CTR;
 78			amd_ctrls_base = MSR_F15H_PERF_CTL;
 79			amd_msr_step = 2;
 80			k7_counters_mirrored = 1;
 81			break;
 82		case 0x10:
 83		case 0x12:
 84		case 0x14:
 85		case 0x16:
 86		default:
 87			amd_num_counters = F10H_NUM_COUNTERS;
 88			amd_counters_base = MSR_K7_PERFCTR0;
 89			amd_ctrls_base = MSR_K7_EVNTSEL0;
 90			amd_msr_step = 1;
 91			k7_counters_mirrored = 0;
 92			break;
 93		}
 94	} else if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) {
 95		amd_num_counters = F10H_NUM_COUNTERS;
 96		amd_counters_base = MSR_K7_PERFCTR0;
 97		amd_ctrls_base = MSR_K7_EVNTSEL0;
 98		amd_msr_step = 1;
 99		k7_counters_mirrored = 0;
100	} else {
101		uint32_t eax, ebx, ecx, edx;
102
103		cpuid(0xa, &eax, &ebx, &ecx, &edx);
104
105		intel_num_arch_counters = (eax & PMU_GENERAL_NR_MASK) >>
106			PMU_GENERAL_NR_SHIFT;
107		intel_num_fixed_counters = (edx & PMU_FIXED_NR_MASK) >>
108			PMU_FIXED_NR_SHIFT;
109	}
110}
111
112static inline uint32_t get_fam15h_addr(u32 addr)
113{
114	switch (addr) {
115	case MSR_K7_PERFCTR0:
116	case MSR_K7_PERFCTR1:
117	case MSR_K7_PERFCTR2:
118	case MSR_K7_PERFCTR3:
119		return MSR_F15H_PERF_CTR + (addr - MSR_K7_PERFCTR0);
120	case MSR_K7_EVNTSEL0:
121	case MSR_K7_EVNTSEL1:
122	case MSR_K7_EVNTSEL2:
123	case MSR_K7_EVNTSEL3:
124		return MSR_F15H_PERF_CTL + (addr - MSR_K7_EVNTSEL0);
125	default:
126		break;
127	}
128
129	return addr;
130}
131
132static inline bool is_amd_pmu_msr(unsigned int msr)
133{
134	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
135	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
136		return false;
137
138	if ((msr >= MSR_F15H_PERF_CTL &&
139	     msr < MSR_F15H_PERF_CTR + (amd_num_counters * 2)) ||
140	    (msr >= MSR_K7_EVNTSEL0 &&
141	     msr < MSR_K7_PERFCTR0 + amd_num_counters))
142		return true;
143
144	return false;
145}
146
147static bool is_intel_pmu_msr(u32 msr_index, int *type, int *index)
148{
149	u32 msr_index_pmc;
150
151	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL &&
152	    boot_cpu_data.x86_vendor != X86_VENDOR_CENTAUR &&
153	    boot_cpu_data.x86_vendor != X86_VENDOR_ZHAOXIN)
154		return false;
155
156	switch (msr_index) {
157	case MSR_CORE_PERF_FIXED_CTR_CTRL:
158	case MSR_IA32_DS_AREA:
159	case MSR_IA32_PEBS_ENABLE:
160		*type = MSR_TYPE_CTRL;
161		return true;
162
163	case MSR_CORE_PERF_GLOBAL_CTRL:
164	case MSR_CORE_PERF_GLOBAL_STATUS:
165	case MSR_CORE_PERF_GLOBAL_OVF_CTRL:
166		*type = MSR_TYPE_GLOBAL;
167		return true;
168
169	default:
170
171		if ((msr_index >= MSR_CORE_PERF_FIXED_CTR0) &&
172		    (msr_index < MSR_CORE_PERF_FIXED_CTR0 +
173				 intel_num_fixed_counters)) {
174			*index = msr_index - MSR_CORE_PERF_FIXED_CTR0;
175			*type = MSR_TYPE_COUNTER;
176			return true;
177		}
178
179		if ((msr_index >= MSR_P6_EVNTSEL0) &&
180		    (msr_index < MSR_P6_EVNTSEL0 +  intel_num_arch_counters)) {
181			*index = msr_index - MSR_P6_EVNTSEL0;
182			*type = MSR_TYPE_ARCH_CTRL;
183			return true;
184		}
185
186		msr_index_pmc = msr_index & MSR_PMC_ALIAS_MASK;
187		if ((msr_index_pmc >= MSR_IA32_PERFCTR0) &&
188		    (msr_index_pmc < MSR_IA32_PERFCTR0 +
189				     intel_num_arch_counters)) {
190			*type = MSR_TYPE_ARCH_COUNTER;
191			*index = msr_index_pmc - MSR_IA32_PERFCTR0;
192			return true;
193		}
194		return false;
195	}
196}
197
198static bool xen_intel_pmu_emulate(unsigned int msr, u64 *val, int type,
199				  int index, bool is_read)
200{
201	uint64_t *reg = NULL;
202	struct xen_pmu_intel_ctxt *ctxt;
203	uint64_t *fix_counters;
204	struct xen_pmu_cntr_pair *arch_cntr_pair;
205	struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
206	uint8_t xenpmu_flags = get_xenpmu_flags();
207
208
209	if (!xenpmu_data || !(xenpmu_flags & XENPMU_IRQ_PROCESSING))
210		return false;
211
212	ctxt = &xenpmu_data->pmu.c.intel;
213
214	switch (msr) {
215	case MSR_CORE_PERF_GLOBAL_OVF_CTRL:
216		reg = &ctxt->global_ovf_ctrl;
217		break;
218	case MSR_CORE_PERF_GLOBAL_STATUS:
219		reg = &ctxt->global_status;
220		break;
221	case MSR_CORE_PERF_GLOBAL_CTRL:
222		reg = &ctxt->global_ctrl;
223		break;
224	case MSR_CORE_PERF_FIXED_CTR_CTRL:
225		reg = &ctxt->fixed_ctrl;
226		break;
227	default:
228		switch (type) {
229		case MSR_TYPE_COUNTER:
230			fix_counters = field_offset(ctxt, fixed_counters);
231			reg = &fix_counters[index];
232			break;
233		case MSR_TYPE_ARCH_COUNTER:
234			arch_cntr_pair = field_offset(ctxt, arch_counters);
235			reg = &arch_cntr_pair[index].counter;
236			break;
237		case MSR_TYPE_ARCH_CTRL:
238			arch_cntr_pair = field_offset(ctxt, arch_counters);
239			reg = &arch_cntr_pair[index].control;
240			break;
241		default:
242			return false;
243		}
244	}
245
246	if (reg) {
247		if (is_read)
248			*val = *reg;
249		else {
250			*reg = *val;
251
252			if (msr == MSR_CORE_PERF_GLOBAL_OVF_CTRL)
253				ctxt->global_status &= (~(*val));
254		}
255		return true;
256	}
257
258	return false;
259}
260
261static bool xen_amd_pmu_emulate(unsigned int msr, u64 *val, bool is_read)
262{
263	uint64_t *reg = NULL;
264	int i, off = 0;
265	struct xen_pmu_amd_ctxt *ctxt;
266	uint64_t *counter_regs, *ctrl_regs;
267	struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
268	uint8_t xenpmu_flags = get_xenpmu_flags();
269
270	if (!xenpmu_data || !(xenpmu_flags & XENPMU_IRQ_PROCESSING))
271		return false;
272
273	if (k7_counters_mirrored &&
274	    ((msr >= MSR_K7_EVNTSEL0) && (msr <= MSR_K7_PERFCTR3)))
275		msr = get_fam15h_addr(msr);
276
277	ctxt = &xenpmu_data->pmu.c.amd;
278	for (i = 0; i < amd_num_counters; i++) {
279		if (msr == amd_ctrls_base + off) {
280			ctrl_regs = field_offset(ctxt, ctrls);
281			reg = &ctrl_regs[i];
282			break;
283		} else if (msr == amd_counters_base + off) {
284			counter_regs = field_offset(ctxt, counters);
285			reg = &counter_regs[i];
286			break;
287		}
288		off += amd_msr_step;
289	}
290
291	if (reg) {
292		if (is_read)
293			*val = *reg;
294		else
295			*reg = *val;
296
297		return true;
298	}
299	return false;
300}
301
302static bool pmu_msr_chk_emulated(unsigned int msr, uint64_t *val, bool is_read,
303				 bool *emul)
304{
305	int type, index = 0;
306
307	if (is_amd_pmu_msr(msr))
308		*emul = xen_amd_pmu_emulate(msr, val, is_read);
309	else if (is_intel_pmu_msr(msr, &type, &index))
310		*emul = xen_intel_pmu_emulate(msr, val, type, index, is_read);
311	else
312		return false;
313
314	return true;
315}
316
317bool pmu_msr_read(unsigned int msr, uint64_t *val, int *err)
318{
319	bool emulated;
320
321	if (!pmu_msr_chk_emulated(msr, val, true, &emulated))
322		return false;
323
324	if (!emulated) {
325		*val = err ? native_read_msr_safe(msr, err)
326			   : native_read_msr(msr);
327	}
328
329	return true;
330}
331
332bool pmu_msr_write(unsigned int msr, uint32_t low, uint32_t high, int *err)
333{
334	uint64_t val = ((uint64_t)high << 32) | low;
335	bool emulated;
336
337	if (!pmu_msr_chk_emulated(msr, &val, false, &emulated))
338		return false;
339
340	if (!emulated) {
341		if (err)
342			*err = native_write_msr_safe(msr, low, high);
343		else
344			native_write_msr(msr, low, high);
345	}
346
347	return true;
348}
349
350static unsigned long long xen_amd_read_pmc(int counter)
351{
352	struct xen_pmu_amd_ctxt *ctxt;
353	uint64_t *counter_regs;
354	struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
355	uint8_t xenpmu_flags = get_xenpmu_flags();
356
357	if (!xenpmu_data || !(xenpmu_flags & XENPMU_IRQ_PROCESSING)) {
358		uint32_t msr;
359		int err;
360
361		msr = amd_counters_base + (counter * amd_msr_step);
362		return native_read_msr_safe(msr, &err);
363	}
364
365	ctxt = &xenpmu_data->pmu.c.amd;
366	counter_regs = field_offset(ctxt, counters);
367	return counter_regs[counter];
368}
369
370static unsigned long long xen_intel_read_pmc(int counter)
371{
372	struct xen_pmu_intel_ctxt *ctxt;
373	uint64_t *fixed_counters;
374	struct xen_pmu_cntr_pair *arch_cntr_pair;
375	struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
376	uint8_t xenpmu_flags = get_xenpmu_flags();
377
378	if (!xenpmu_data || !(xenpmu_flags & XENPMU_IRQ_PROCESSING)) {
379		uint32_t msr;
380		int err;
381
382		if (counter & (1 << INTEL_PMC_TYPE_SHIFT))
383			msr = MSR_CORE_PERF_FIXED_CTR0 + (counter & 0xffff);
384		else
385			msr = MSR_IA32_PERFCTR0 + counter;
386
387		return native_read_msr_safe(msr, &err);
388	}
389
390	ctxt = &xenpmu_data->pmu.c.intel;
391	if (counter & (1 << INTEL_PMC_TYPE_SHIFT)) {
392		fixed_counters = field_offset(ctxt, fixed_counters);
393		return fixed_counters[counter & 0xffff];
394	}
395
396	arch_cntr_pair = field_offset(ctxt, arch_counters);
397	return arch_cntr_pair[counter].counter;
398}
399
400unsigned long long xen_read_pmc(int counter)
401{
402	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
403		return xen_amd_read_pmc(counter);
404	else
405		return xen_intel_read_pmc(counter);
406}
407
408int pmu_apic_update(uint32_t val)
409{
410	int ret;
411	struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
412
413	if (!xenpmu_data) {
414		pr_warn_once("%s: pmudata not initialized\n", __func__);
415		return -EINVAL;
416	}
417
418	xenpmu_data->pmu.l.lapic_lvtpc = val;
419
420	if (get_xenpmu_flags() & XENPMU_IRQ_PROCESSING)
421		return 0;
422
423	ret = HYPERVISOR_xenpmu_op(XENPMU_lvtpc_set, NULL);
424
425	return ret;
426}
427
428/* perf callbacks */
429static unsigned int xen_guest_state(void)
430{
431	const struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
432	unsigned int state = 0;
433
434	if (!xenpmu_data) {
435		pr_warn_once("%s: pmudata not initialized\n", __func__);
436		return state;
437	}
438
439	if (!xen_initial_domain() || (xenpmu_data->domain_id >= DOMID_SELF))
440		return state;
441
442	state |= PERF_GUEST_ACTIVE;
443
444	if (xenpmu_data->pmu.pmu_flags & PMU_SAMPLE_PV) {
445		if (xenpmu_data->pmu.pmu_flags & PMU_SAMPLE_USER)
446			state |= PERF_GUEST_USER;
447	} else if (xenpmu_data->pmu.r.regs.cpl & 3) {
448		state |= PERF_GUEST_USER;
449	}
450
451	return state;
452}
453
454static unsigned long xen_get_guest_ip(void)
455{
456	const struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
457
458	if (!xenpmu_data) {
459		pr_warn_once("%s: pmudata not initialized\n", __func__);
460		return 0;
461	}
462
463	return xenpmu_data->pmu.r.regs.ip;
464}
465
466static struct perf_guest_info_callbacks xen_guest_cbs = {
467	.state                  = xen_guest_state,
468	.get_ip			= xen_get_guest_ip,
469};
470
471/* Convert registers from Xen's format to Linux' */
472static void xen_convert_regs(const struct xen_pmu_regs *xen_regs,
473			     struct pt_regs *regs, uint64_t pmu_flags)
474{
475	regs->ip = xen_regs->ip;
476	regs->cs = xen_regs->cs;
477	regs->sp = xen_regs->sp;
478
479	if (pmu_flags & PMU_SAMPLE_PV) {
480		if (pmu_flags & PMU_SAMPLE_USER)
481			regs->cs |= 3;
482		else
483			regs->cs &= ~3;
484	} else {
485		if (xen_regs->cpl)
486			regs->cs |= 3;
487		else
488			regs->cs &= ~3;
489	}
490}
491
492irqreturn_t xen_pmu_irq_handler(int irq, void *dev_id)
493{
494	int err, ret = IRQ_NONE;
495	struct pt_regs regs = {0};
496	const struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
497	uint8_t xenpmu_flags = get_xenpmu_flags();
498
499	if (!xenpmu_data) {
500		pr_warn_once("%s: pmudata not initialized\n", __func__);
501		return ret;
502	}
503
504	this_cpu_ptr(&xenpmu_shared)->flags =
505		xenpmu_flags | XENPMU_IRQ_PROCESSING;
506	xen_convert_regs(&xenpmu_data->pmu.r.regs, &regs,
507			 xenpmu_data->pmu.pmu_flags);
508	if (x86_pmu.handle_irq(&regs))
509		ret = IRQ_HANDLED;
510
511	/* Write out cached context to HW */
512	err = HYPERVISOR_xenpmu_op(XENPMU_flush, NULL);
513	this_cpu_ptr(&xenpmu_shared)->flags = xenpmu_flags;
514	if (err) {
515		pr_warn_once("%s: failed hypercall, err: %d\n", __func__, err);
516		return IRQ_NONE;
517	}
518
519	return ret;
520}
521
522bool is_xen_pmu;
523
524void xen_pmu_init(int cpu)
525{
526	int err;
527	struct xen_pmu_params xp;
528	unsigned long pfn;
529	struct xen_pmu_data *xenpmu_data;
530
531	BUILD_BUG_ON(sizeof(struct xen_pmu_data) > PAGE_SIZE);
532
533	if (xen_hvm_domain() || (cpu != 0 && !is_xen_pmu))
534		return;
535
536	xenpmu_data = (struct xen_pmu_data *)get_zeroed_page(GFP_KERNEL);
537	if (!xenpmu_data) {
538		pr_err("VPMU init: No memory\n");
539		return;
540	}
541	pfn = virt_to_pfn(xenpmu_data);
542
543	xp.val = pfn_to_mfn(pfn);
544	xp.vcpu = cpu;
545	xp.version.maj = XENPMU_VER_MAJ;
546	xp.version.min = XENPMU_VER_MIN;
547	err = HYPERVISOR_xenpmu_op(XENPMU_init, &xp);
548	if (err)
549		goto fail;
550
551	per_cpu(xenpmu_shared, cpu).xenpmu_data = xenpmu_data;
552	per_cpu(xenpmu_shared, cpu).flags = 0;
553
554	if (!is_xen_pmu) {
555		is_xen_pmu = true;
556		perf_register_guest_info_callbacks(&xen_guest_cbs);
557		xen_pmu_arch_init();
558	}
559
560	return;
561
562fail:
563	if (err == -EOPNOTSUPP || err == -ENOSYS)
564		pr_info_once("VPMU disabled by hypervisor.\n");
565	else
566		pr_info_once("Could not initialize VPMU for cpu %d, error %d\n",
567			cpu, err);
568	free_pages((unsigned long)xenpmu_data, 0);
569}
570
571void xen_pmu_finish(int cpu)
572{
573	struct xen_pmu_params xp;
574
575	if (xen_hvm_domain())
576		return;
577
578	xp.vcpu = cpu;
579	xp.version.maj = XENPMU_VER_MAJ;
580	xp.version.min = XENPMU_VER_MIN;
581
582	(void)HYPERVISOR_xenpmu_op(XENPMU_finish, &xp);
583
584	free_pages((unsigned long)per_cpu(xenpmu_shared, cpu).xenpmu_data, 0);
585	per_cpu(xenpmu_shared, cpu).xenpmu_data = NULL;
586}
v6.9.4
  1// SPDX-License-Identifier: GPL-2.0
  2#include <linux/types.h>
  3#include <linux/interrupt.h>
  4
  5#include <asm/xen/hypercall.h>
  6#include <xen/xen.h>
  7#include <xen/page.h>
  8#include <xen/interface/xen.h>
  9#include <xen/interface/vcpu.h>
 10#include <xen/interface/xenpmu.h>
 11
 12#include "xen-ops.h"
 13#include "pmu.h"
 14
 15/* x86_pmu.handle_irq definition */
 16#include "../events/perf_event.h"
 17
 18#define XENPMU_IRQ_PROCESSING    1
 19struct xenpmu {
 20	/* Shared page between hypervisor and domain */
 21	struct xen_pmu_data *xenpmu_data;
 22
 23	uint8_t flags;
 24};
 25static DEFINE_PER_CPU(struct xenpmu, xenpmu_shared);
 26#define get_xenpmu_data()    (this_cpu_ptr(&xenpmu_shared)->xenpmu_data)
 27#define get_xenpmu_flags()   (this_cpu_ptr(&xenpmu_shared)->flags)
 28
 29/* Macro for computing address of a PMU MSR bank */
 30#define field_offset(ctxt, field) ((void *)((uintptr_t)ctxt + \
 31					    (uintptr_t)ctxt->field))
 32
 33/* AMD PMU */
 34#define F15H_NUM_COUNTERS   6
 35#define F10H_NUM_COUNTERS   4
 36
 37static __read_mostly uint32_t amd_counters_base;
 38static __read_mostly uint32_t amd_ctrls_base;
 39static __read_mostly int amd_msr_step;
 40static __read_mostly int k7_counters_mirrored;
 41static __read_mostly int amd_num_counters;
 42
 43/* Intel PMU */
 44#define MSR_TYPE_COUNTER            0
 45#define MSR_TYPE_CTRL               1
 46#define MSR_TYPE_GLOBAL             2
 47#define MSR_TYPE_ARCH_COUNTER       3
 48#define MSR_TYPE_ARCH_CTRL          4
 49
 50/* Number of general pmu registers (CPUID.EAX[0xa].EAX[8..15]) */
 51#define PMU_GENERAL_NR_SHIFT        8
 52#define PMU_GENERAL_NR_BITS         8
 53#define PMU_GENERAL_NR_MASK         (((1 << PMU_GENERAL_NR_BITS) - 1) \
 54				     << PMU_GENERAL_NR_SHIFT)
 55
 56/* Number of fixed pmu registers (CPUID.EDX[0xa].EDX[0..4]) */
 57#define PMU_FIXED_NR_SHIFT          0
 58#define PMU_FIXED_NR_BITS           5
 59#define PMU_FIXED_NR_MASK           (((1 << PMU_FIXED_NR_BITS) - 1) \
 60				     << PMU_FIXED_NR_SHIFT)
 61
 62/* Alias registers (0x4c1) for full-width writes to PMCs */
 63#define MSR_PMC_ALIAS_MASK          (~(MSR_IA32_PERFCTR0 ^ MSR_IA32_PMC0))
 64
 65#define INTEL_PMC_TYPE_SHIFT        30
 66
 67static __read_mostly int intel_num_arch_counters, intel_num_fixed_counters;
 68
 69
 70static void xen_pmu_arch_init(void)
 71{
 72	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {
 73
 74		switch (boot_cpu_data.x86) {
 75		case 0x15:
 76			amd_num_counters = F15H_NUM_COUNTERS;
 77			amd_counters_base = MSR_F15H_PERF_CTR;
 78			amd_ctrls_base = MSR_F15H_PERF_CTL;
 79			amd_msr_step = 2;
 80			k7_counters_mirrored = 1;
 81			break;
 82		case 0x10:
 83		case 0x12:
 84		case 0x14:
 85		case 0x16:
 86		default:
 87			amd_num_counters = F10H_NUM_COUNTERS;
 88			amd_counters_base = MSR_K7_PERFCTR0;
 89			amd_ctrls_base = MSR_K7_EVNTSEL0;
 90			amd_msr_step = 1;
 91			k7_counters_mirrored = 0;
 92			break;
 93		}
 94	} else if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) {
 95		amd_num_counters = F10H_NUM_COUNTERS;
 96		amd_counters_base = MSR_K7_PERFCTR0;
 97		amd_ctrls_base = MSR_K7_EVNTSEL0;
 98		amd_msr_step = 1;
 99		k7_counters_mirrored = 0;
100	} else {
101		uint32_t eax, ebx, ecx, edx;
102
103		cpuid(0xa, &eax, &ebx, &ecx, &edx);
104
105		intel_num_arch_counters = (eax & PMU_GENERAL_NR_MASK) >>
106			PMU_GENERAL_NR_SHIFT;
107		intel_num_fixed_counters = (edx & PMU_FIXED_NR_MASK) >>
108			PMU_FIXED_NR_SHIFT;
109	}
110}
111
112static inline uint32_t get_fam15h_addr(u32 addr)
113{
114	switch (addr) {
115	case MSR_K7_PERFCTR0:
116	case MSR_K7_PERFCTR1:
117	case MSR_K7_PERFCTR2:
118	case MSR_K7_PERFCTR3:
119		return MSR_F15H_PERF_CTR + (addr - MSR_K7_PERFCTR0);
120	case MSR_K7_EVNTSEL0:
121	case MSR_K7_EVNTSEL1:
122	case MSR_K7_EVNTSEL2:
123	case MSR_K7_EVNTSEL3:
124		return MSR_F15H_PERF_CTL + (addr - MSR_K7_EVNTSEL0);
125	default:
126		break;
127	}
128
129	return addr;
130}
131
132static inline bool is_amd_pmu_msr(unsigned int msr)
133{
134	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
135	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
136		return false;
137
138	if ((msr >= MSR_F15H_PERF_CTL &&
139	     msr < MSR_F15H_PERF_CTR + (amd_num_counters * 2)) ||
140	    (msr >= MSR_K7_EVNTSEL0 &&
141	     msr < MSR_K7_PERFCTR0 + amd_num_counters))
142		return true;
143
144	return false;
145}
146
147static bool is_intel_pmu_msr(u32 msr_index, int *type, int *index)
148{
149	u32 msr_index_pmc;
150
151	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL &&
152	    boot_cpu_data.x86_vendor != X86_VENDOR_CENTAUR &&
153	    boot_cpu_data.x86_vendor != X86_VENDOR_ZHAOXIN)
154		return false;
155
156	switch (msr_index) {
157	case MSR_CORE_PERF_FIXED_CTR_CTRL:
158	case MSR_IA32_DS_AREA:
159	case MSR_IA32_PEBS_ENABLE:
160		*type = MSR_TYPE_CTRL;
161		return true;
162
163	case MSR_CORE_PERF_GLOBAL_CTRL:
164	case MSR_CORE_PERF_GLOBAL_STATUS:
165	case MSR_CORE_PERF_GLOBAL_OVF_CTRL:
166		*type = MSR_TYPE_GLOBAL;
167		return true;
168
169	default:
170
171		if ((msr_index >= MSR_CORE_PERF_FIXED_CTR0) &&
172		    (msr_index < MSR_CORE_PERF_FIXED_CTR0 +
173				 intel_num_fixed_counters)) {
174			*index = msr_index - MSR_CORE_PERF_FIXED_CTR0;
175			*type = MSR_TYPE_COUNTER;
176			return true;
177		}
178
179		if ((msr_index >= MSR_P6_EVNTSEL0) &&
180		    (msr_index < MSR_P6_EVNTSEL0 +  intel_num_arch_counters)) {
181			*index = msr_index - MSR_P6_EVNTSEL0;
182			*type = MSR_TYPE_ARCH_CTRL;
183			return true;
184		}
185
186		msr_index_pmc = msr_index & MSR_PMC_ALIAS_MASK;
187		if ((msr_index_pmc >= MSR_IA32_PERFCTR0) &&
188		    (msr_index_pmc < MSR_IA32_PERFCTR0 +
189				     intel_num_arch_counters)) {
190			*type = MSR_TYPE_ARCH_COUNTER;
191			*index = msr_index_pmc - MSR_IA32_PERFCTR0;
192			return true;
193		}
194		return false;
195	}
196}
197
198static bool xen_intel_pmu_emulate(unsigned int msr, u64 *val, int type,
199				  int index, bool is_read)
200{
201	uint64_t *reg = NULL;
202	struct xen_pmu_intel_ctxt *ctxt;
203	uint64_t *fix_counters;
204	struct xen_pmu_cntr_pair *arch_cntr_pair;
205	struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
206	uint8_t xenpmu_flags = get_xenpmu_flags();
207
208
209	if (!xenpmu_data || !(xenpmu_flags & XENPMU_IRQ_PROCESSING))
210		return false;
211
212	ctxt = &xenpmu_data->pmu.c.intel;
213
214	switch (msr) {
215	case MSR_CORE_PERF_GLOBAL_OVF_CTRL:
216		reg = &ctxt->global_ovf_ctrl;
217		break;
218	case MSR_CORE_PERF_GLOBAL_STATUS:
219		reg = &ctxt->global_status;
220		break;
221	case MSR_CORE_PERF_GLOBAL_CTRL:
222		reg = &ctxt->global_ctrl;
223		break;
224	case MSR_CORE_PERF_FIXED_CTR_CTRL:
225		reg = &ctxt->fixed_ctrl;
226		break;
227	default:
228		switch (type) {
229		case MSR_TYPE_COUNTER:
230			fix_counters = field_offset(ctxt, fixed_counters);
231			reg = &fix_counters[index];
232			break;
233		case MSR_TYPE_ARCH_COUNTER:
234			arch_cntr_pair = field_offset(ctxt, arch_counters);
235			reg = &arch_cntr_pair[index].counter;
236			break;
237		case MSR_TYPE_ARCH_CTRL:
238			arch_cntr_pair = field_offset(ctxt, arch_counters);
239			reg = &arch_cntr_pair[index].control;
240			break;
241		default:
242			return false;
243		}
244	}
245
246	if (reg) {
247		if (is_read)
248			*val = *reg;
249		else {
250			*reg = *val;
251
252			if (msr == MSR_CORE_PERF_GLOBAL_OVF_CTRL)
253				ctxt->global_status &= (~(*val));
254		}
255		return true;
256	}
257
258	return false;
259}
260
261static bool xen_amd_pmu_emulate(unsigned int msr, u64 *val, bool is_read)
262{
263	uint64_t *reg = NULL;
264	int i, off = 0;
265	struct xen_pmu_amd_ctxt *ctxt;
266	uint64_t *counter_regs, *ctrl_regs;
267	struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
268	uint8_t xenpmu_flags = get_xenpmu_flags();
269
270	if (!xenpmu_data || !(xenpmu_flags & XENPMU_IRQ_PROCESSING))
271		return false;
272
273	if (k7_counters_mirrored &&
274	    ((msr >= MSR_K7_EVNTSEL0) && (msr <= MSR_K7_PERFCTR3)))
275		msr = get_fam15h_addr(msr);
276
277	ctxt = &xenpmu_data->pmu.c.amd;
278	for (i = 0; i < amd_num_counters; i++) {
279		if (msr == amd_ctrls_base + off) {
280			ctrl_regs = field_offset(ctxt, ctrls);
281			reg = &ctrl_regs[i];
282			break;
283		} else if (msr == amd_counters_base + off) {
284			counter_regs = field_offset(ctxt, counters);
285			reg = &counter_regs[i];
286			break;
287		}
288		off += amd_msr_step;
289	}
290
291	if (reg) {
292		if (is_read)
293			*val = *reg;
294		else
295			*reg = *val;
296
297		return true;
298	}
299	return false;
300}
301
302static bool pmu_msr_chk_emulated(unsigned int msr, uint64_t *val, bool is_read,
303				 bool *emul)
304{
305	int type, index = 0;
306
307	if (is_amd_pmu_msr(msr))
308		*emul = xen_amd_pmu_emulate(msr, val, is_read);
309	else if (is_intel_pmu_msr(msr, &type, &index))
310		*emul = xen_intel_pmu_emulate(msr, val, type, index, is_read);
311	else
312		return false;
313
314	return true;
315}
316
317bool pmu_msr_read(unsigned int msr, uint64_t *val, int *err)
318{
319	bool emulated;
320
321	if (!pmu_msr_chk_emulated(msr, val, true, &emulated))
322		return false;
323
324	if (!emulated) {
325		*val = err ? native_read_msr_safe(msr, err)
326			   : native_read_msr(msr);
327	}
328
329	return true;
330}
331
332bool pmu_msr_write(unsigned int msr, uint32_t low, uint32_t high, int *err)
333{
334	uint64_t val = ((uint64_t)high << 32) | low;
335	bool emulated;
336
337	if (!pmu_msr_chk_emulated(msr, &val, false, &emulated))
338		return false;
339
340	if (!emulated) {
341		if (err)
342			*err = native_write_msr_safe(msr, low, high);
343		else
344			native_write_msr(msr, low, high);
345	}
346
347	return true;
348}
349
350static unsigned long long xen_amd_read_pmc(int counter)
351{
352	struct xen_pmu_amd_ctxt *ctxt;
353	uint64_t *counter_regs;
354	struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
355	uint8_t xenpmu_flags = get_xenpmu_flags();
356
357	if (!xenpmu_data || !(xenpmu_flags & XENPMU_IRQ_PROCESSING)) {
358		uint32_t msr;
359		int err;
360
361		msr = amd_counters_base + (counter * amd_msr_step);
362		return native_read_msr_safe(msr, &err);
363	}
364
365	ctxt = &xenpmu_data->pmu.c.amd;
366	counter_regs = field_offset(ctxt, counters);
367	return counter_regs[counter];
368}
369
370static unsigned long long xen_intel_read_pmc(int counter)
371{
372	struct xen_pmu_intel_ctxt *ctxt;
373	uint64_t *fixed_counters;
374	struct xen_pmu_cntr_pair *arch_cntr_pair;
375	struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
376	uint8_t xenpmu_flags = get_xenpmu_flags();
377
378	if (!xenpmu_data || !(xenpmu_flags & XENPMU_IRQ_PROCESSING)) {
379		uint32_t msr;
380		int err;
381
382		if (counter & (1 << INTEL_PMC_TYPE_SHIFT))
383			msr = MSR_CORE_PERF_FIXED_CTR0 + (counter & 0xffff);
384		else
385			msr = MSR_IA32_PERFCTR0 + counter;
386
387		return native_read_msr_safe(msr, &err);
388	}
389
390	ctxt = &xenpmu_data->pmu.c.intel;
391	if (counter & (1 << INTEL_PMC_TYPE_SHIFT)) {
392		fixed_counters = field_offset(ctxt, fixed_counters);
393		return fixed_counters[counter & 0xffff];
394	}
395
396	arch_cntr_pair = field_offset(ctxt, arch_counters);
397	return arch_cntr_pair[counter].counter;
398}
399
400unsigned long long xen_read_pmc(int counter)
401{
402	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
403		return xen_amd_read_pmc(counter);
404	else
405		return xen_intel_read_pmc(counter);
406}
407
408int pmu_apic_update(uint32_t val)
409{
410	int ret;
411	struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
412
413	if (!xenpmu_data) {
414		pr_warn_once("%s: pmudata not initialized\n", __func__);
415		return -EINVAL;
416	}
417
418	xenpmu_data->pmu.l.lapic_lvtpc = val;
419
420	if (get_xenpmu_flags() & XENPMU_IRQ_PROCESSING)
421		return 0;
422
423	ret = HYPERVISOR_xenpmu_op(XENPMU_lvtpc_set, NULL);
424
425	return ret;
426}
427
428/* perf callbacks */
429static unsigned int xen_guest_state(void)
430{
431	const struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
432	unsigned int state = 0;
433
434	if (!xenpmu_data) {
435		pr_warn_once("%s: pmudata not initialized\n", __func__);
436		return state;
437	}
438
439	if (!xen_initial_domain() || (xenpmu_data->domain_id >= DOMID_SELF))
440		return state;
441
442	state |= PERF_GUEST_ACTIVE;
443
444	if (xenpmu_data->pmu.pmu_flags & PMU_SAMPLE_PV) {
445		if (xenpmu_data->pmu.pmu_flags & PMU_SAMPLE_USER)
446			state |= PERF_GUEST_USER;
447	} else if (xenpmu_data->pmu.r.regs.cpl & 3) {
448		state |= PERF_GUEST_USER;
449	}
450
451	return state;
452}
453
454static unsigned long xen_get_guest_ip(void)
455{
456	const struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
457
458	if (!xenpmu_data) {
459		pr_warn_once("%s: pmudata not initialized\n", __func__);
460		return 0;
461	}
462
463	return xenpmu_data->pmu.r.regs.ip;
464}
465
466static struct perf_guest_info_callbacks xen_guest_cbs = {
467	.state                  = xen_guest_state,
468	.get_ip			= xen_get_guest_ip,
469};
470
471/* Convert registers from Xen's format to Linux' */
472static void xen_convert_regs(const struct xen_pmu_regs *xen_regs,
473			     struct pt_regs *regs, uint64_t pmu_flags)
474{
475	regs->ip = xen_regs->ip;
476	regs->cs = xen_regs->cs;
477	regs->sp = xen_regs->sp;
478
479	if (pmu_flags & PMU_SAMPLE_PV) {
480		if (pmu_flags & PMU_SAMPLE_USER)
481			regs->cs |= 3;
482		else
483			regs->cs &= ~3;
484	} else {
485		if (xen_regs->cpl)
486			regs->cs |= 3;
487		else
488			regs->cs &= ~3;
489	}
490}
491
492irqreturn_t xen_pmu_irq_handler(int irq, void *dev_id)
493{
494	int err, ret = IRQ_NONE;
495	struct pt_regs regs = {0};
496	const struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
497	uint8_t xenpmu_flags = get_xenpmu_flags();
498
499	if (!xenpmu_data) {
500		pr_warn_once("%s: pmudata not initialized\n", __func__);
501		return ret;
502	}
503
504	this_cpu_ptr(&xenpmu_shared)->flags =
505		xenpmu_flags | XENPMU_IRQ_PROCESSING;
506	xen_convert_regs(&xenpmu_data->pmu.r.regs, &regs,
507			 xenpmu_data->pmu.pmu_flags);
508	if (x86_pmu.handle_irq(&regs))
509		ret = IRQ_HANDLED;
510
511	/* Write out cached context to HW */
512	err = HYPERVISOR_xenpmu_op(XENPMU_flush, NULL);
513	this_cpu_ptr(&xenpmu_shared)->flags = xenpmu_flags;
514	if (err) {
515		pr_warn_once("%s: failed hypercall, err: %d\n", __func__, err);
516		return IRQ_NONE;
517	}
518
519	return ret;
520}
521
522bool is_xen_pmu;
523
524void xen_pmu_init(int cpu)
525{
526	int err;
527	struct xen_pmu_params xp;
528	unsigned long pfn;
529	struct xen_pmu_data *xenpmu_data;
530
531	BUILD_BUG_ON(sizeof(struct xen_pmu_data) > PAGE_SIZE);
532
533	if (xen_hvm_domain() || (cpu != 0 && !is_xen_pmu))
534		return;
535
536	xenpmu_data = (struct xen_pmu_data *)get_zeroed_page(GFP_KERNEL);
537	if (!xenpmu_data) {
538		pr_err("VPMU init: No memory\n");
539		return;
540	}
541	pfn = virt_to_pfn(xenpmu_data);
542
543	xp.val = pfn_to_mfn(pfn);
544	xp.vcpu = cpu;
545	xp.version.maj = XENPMU_VER_MAJ;
546	xp.version.min = XENPMU_VER_MIN;
547	err = HYPERVISOR_xenpmu_op(XENPMU_init, &xp);
548	if (err)
549		goto fail;
550
551	per_cpu(xenpmu_shared, cpu).xenpmu_data = xenpmu_data;
552	per_cpu(xenpmu_shared, cpu).flags = 0;
553
554	if (!is_xen_pmu) {
555		is_xen_pmu = true;
556		perf_register_guest_info_callbacks(&xen_guest_cbs);
557		xen_pmu_arch_init();
558	}
559
560	return;
561
562fail:
563	if (err == -EOPNOTSUPP || err == -ENOSYS)
564		pr_info_once("VPMU disabled by hypervisor.\n");
565	else
566		pr_info_once("Could not initialize VPMU for cpu %d, error %d\n",
567			cpu, err);
568	free_pages((unsigned long)xenpmu_data, 0);
569}
570
571void xen_pmu_finish(int cpu)
572{
573	struct xen_pmu_params xp;
574
575	if (xen_hvm_domain())
576		return;
577
578	xp.vcpu = cpu;
579	xp.version.maj = XENPMU_VER_MAJ;
580	xp.version.min = XENPMU_VER_MIN;
581
582	(void)HYPERVISOR_xenpmu_op(XENPMU_finish, &xp);
583
584	free_pages((unsigned long)per_cpu(xenpmu_shared, cpu).xenpmu_data, 0);
585	per_cpu(xenpmu_shared, cpu).xenpmu_data = NULL;
586}