1 #ifdef CONFIG_CPU_SUP_INTEL
3 /* The maximal number of PEBS events: */
4 #define MAX_PEBS_EVENTS 4
6 /* The size of a BTS record in bytes: */
7 #define BTS_RECORD_SIZE 24
9 #define BTS_BUFFER_SIZE (PAGE_SIZE << 4)
10 #define PEBS_BUFFER_SIZE PAGE_SIZE
13 * pebs_record_32 for p4 and core not supported
15 struct pebs_record_32 {
23 struct pebs_record_core {
28 u64 r12, r13, r14, r15;
31 struct pebs_record_nhm {
36 u64 r12, r13, r14, r15;
37 u64 status, dla, dse, lat;
41 * Bits in the debugctlmsr controlling branch tracing.
43 #define X86_DEBUGCTL_TR (1 << 6)
44 #define X86_DEBUGCTL_BTS (1 << 7)
45 #define X86_DEBUGCTL_BTINT (1 << 8)
46 #define X86_DEBUGCTL_BTS_OFF_OS (1 << 9)
47 #define X86_DEBUGCTL_BTS_OFF_USR (1 << 10)
50 * A debug store configuration.
52 * We only support architectures that use 64bit fields.
57 u64 bts_absolute_maximum;
58 u64 bts_interrupt_threshold;
61 u64 pebs_absolute_maximum;
62 u64 pebs_interrupt_threshold;
63 u64 pebs_event_reset[MAX_PEBS_EVENTS];
66 static void init_debug_store_on_cpu(int cpu)
68 struct debug_store *ds = per_cpu(cpu_hw_events, cpu).ds;
73 wrmsr_on_cpu(cpu, MSR_IA32_DS_AREA,
74 (u32)((u64)(unsigned long)ds),
75 (u32)((u64)(unsigned long)ds >> 32));
78 static void fini_debug_store_on_cpu(int cpu)
80 if (!per_cpu(cpu_hw_events, cpu).ds)
83 wrmsr_on_cpu(cpu, MSR_IA32_DS_AREA, 0, 0);
86 static void release_ds_buffers(void)
90 if (!x86_pmu.bts && !x86_pmu.pebs)
95 for_each_online_cpu(cpu)
96 fini_debug_store_on_cpu(cpu);
98 for_each_possible_cpu(cpu) {
99 struct debug_store *ds = per_cpu(cpu_hw_events, cpu).ds;
104 per_cpu(cpu_hw_events, cpu).ds = NULL;
106 kfree((void *)(unsigned long)ds->pebs_buffer_base);
107 kfree((void *)(unsigned long)ds->bts_buffer_base);
114 static int reserve_ds_buffers(void)
118 if (!x86_pmu.bts && !x86_pmu.pebs)
123 for_each_possible_cpu(cpu) {
124 struct debug_store *ds;
129 ds = kzalloc(sizeof(*ds), GFP_KERNEL);
132 per_cpu(cpu_hw_events, cpu).ds = ds;
135 buffer = kzalloc(BTS_BUFFER_SIZE, GFP_KERNEL);
136 if (unlikely(!buffer))
139 max = BTS_BUFFER_SIZE / BTS_RECORD_SIZE;
142 ds->bts_buffer_base = (u64)(unsigned long)buffer;
143 ds->bts_index = ds->bts_buffer_base;
144 ds->bts_absolute_maximum = ds->bts_buffer_base +
145 max * BTS_RECORD_SIZE;
146 ds->bts_interrupt_threshold = ds->bts_absolute_maximum -
147 thresh * BTS_RECORD_SIZE;
151 buffer = kzalloc(PEBS_BUFFER_SIZE, GFP_KERNEL);
152 if (unlikely(!buffer))
155 max = PEBS_BUFFER_SIZE / x86_pmu.pebs_record_size;
157 ds->pebs_buffer_base = (u64)(unsigned long)buffer;
158 ds->pebs_index = ds->pebs_buffer_base;
159 ds->pebs_absolute_maximum = ds->pebs_buffer_base +
160 max * x86_pmu.pebs_record_size;
162 * Always use single record PEBS
164 ds->pebs_interrupt_threshold = ds->pebs_buffer_base +
165 x86_pmu.pebs_record_size;
172 release_ds_buffers();
174 for_each_online_cpu(cpu)
175 init_debug_store_on_cpu(cpu);
187 static struct event_constraint bts_constraint =
188 EVENT_CONSTRAINT(0, 1ULL << X86_PMC_IDX_FIXED_BTS, 0);
190 static void intel_pmu_enable_bts(u64 config)
192 unsigned long debugctlmsr;
194 debugctlmsr = get_debugctlmsr();
196 debugctlmsr |= X86_DEBUGCTL_TR;
197 debugctlmsr |= X86_DEBUGCTL_BTS;
198 debugctlmsr |= X86_DEBUGCTL_BTINT;
200 if (!(config & ARCH_PERFMON_EVENTSEL_OS))
201 debugctlmsr |= X86_DEBUGCTL_BTS_OFF_OS;
203 if (!(config & ARCH_PERFMON_EVENTSEL_USR))
204 debugctlmsr |= X86_DEBUGCTL_BTS_OFF_USR;
206 update_debugctlmsr(debugctlmsr);
209 static void intel_pmu_disable_bts(void)
211 struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
212 unsigned long debugctlmsr;
217 debugctlmsr = get_debugctlmsr();
220 ~(X86_DEBUGCTL_TR | X86_DEBUGCTL_BTS | X86_DEBUGCTL_BTINT |
221 X86_DEBUGCTL_BTS_OFF_OS | X86_DEBUGCTL_BTS_OFF_USR);
223 update_debugctlmsr(debugctlmsr);
226 static void intel_pmu_drain_bts_buffer(void)
228 struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
229 struct debug_store *ds = cpuc->ds;
235 struct perf_event *event = cpuc->events[X86_PMC_IDX_FIXED_BTS];
236 struct bts_record *at, *top;
237 struct perf_output_handle handle;
238 struct perf_event_header header;
239 struct perf_sample_data data;
248 at = (struct bts_record *)(unsigned long)ds->bts_buffer_base;
249 top = (struct bts_record *)(unsigned long)ds->bts_index;
254 ds->bts_index = ds->bts_buffer_base;
256 perf_sample_data_init(&data, 0);
257 data.period = event->hw.last_period;
261 * Prepare a generic sample, i.e. fill in the invariant fields.
262 * We will overwrite the from and to address before we output
265 perf_prepare_sample(&header, &data, event, ®s);
267 if (perf_output_begin(&handle, event, header.size * (top - at), 1, 1))
270 for (; at < top; at++) {
274 perf_output_sample(&handle, &header, &data, event);
277 perf_output_end(&handle);
279 /* There's new data available. */
280 event->hw.interrupts++;
281 event->pending_kill = POLL_IN;
288 static struct event_constraint intel_core_pebs_events[] = {
289 PEBS_EVENT_CONSTRAINT(0x00c0, 0x1), /* INSTR_RETIRED.ANY */
290 PEBS_EVENT_CONSTRAINT(0xfec1, 0x1), /* X87_OPS_RETIRED.ANY */
291 PEBS_EVENT_CONSTRAINT(0x00c5, 0x1), /* BR_INST_RETIRED.MISPRED */
292 PEBS_EVENT_CONSTRAINT(0x1fc7, 0x1), /* SIMD_INST_RETURED.ANY */
293 PEBS_EVENT_CONSTRAINT(0x01cb, 0x1), /* MEM_LOAD_RETIRED.L1D_MISS */
294 PEBS_EVENT_CONSTRAINT(0x02cb, 0x1), /* MEM_LOAD_RETIRED.L1D_LINE_MISS */
295 PEBS_EVENT_CONSTRAINT(0x04cb, 0x1), /* MEM_LOAD_RETIRED.L2_MISS */
296 PEBS_EVENT_CONSTRAINT(0x08cb, 0x1), /* MEM_LOAD_RETIRED.L2_LINE_MISS */
297 PEBS_EVENT_CONSTRAINT(0x10cb, 0x1), /* MEM_LOAD_RETIRED.DTLB_MISS */
301 static struct event_constraint intel_nehalem_pebs_events[] = {
302 PEBS_EVENT_CONSTRAINT(0x00c0, 0xf), /* INSTR_RETIRED.ANY */
303 PEBS_EVENT_CONSTRAINT(0xfec1, 0xf), /* X87_OPS_RETIRED.ANY */
304 PEBS_EVENT_CONSTRAINT(0x00c5, 0xf), /* BR_INST_RETIRED.MISPRED */
305 PEBS_EVENT_CONSTRAINT(0x1fc7, 0xf), /* SIMD_INST_RETURED.ANY */
306 PEBS_EVENT_CONSTRAINT(0x01cb, 0xf), /* MEM_LOAD_RETIRED.L1D_MISS */
307 PEBS_EVENT_CONSTRAINT(0x02cb, 0xf), /* MEM_LOAD_RETIRED.L1D_LINE_MISS */
308 PEBS_EVENT_CONSTRAINT(0x04cb, 0xf), /* MEM_LOAD_RETIRED.L2_MISS */
309 PEBS_EVENT_CONSTRAINT(0x08cb, 0xf), /* MEM_LOAD_RETIRED.L2_LINE_MISS */
310 PEBS_EVENT_CONSTRAINT(0x10cb, 0xf), /* MEM_LOAD_RETIRED.DTLB_MISS */
314 static struct event_constraint *
315 intel_pebs_constraints(struct perf_event *event)
317 struct event_constraint *c;
319 if (!event->attr.precise)
322 if (x86_pmu.pebs_constraints) {
323 for_each_event_constraint(c, x86_pmu.pebs_constraints) {
324 if ((event->hw.config & c->cmask) == c->code)
329 return &emptyconstraint;
332 static void intel_pmu_pebs_enable(struct perf_event *event)
334 struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
335 struct hw_perf_event *hwc = &event->hw;
336 u64 val = cpuc->pebs_enabled;
338 hwc->config &= ~ARCH_PERFMON_EVENTSEL_INT;
340 val |= 1ULL << hwc->idx;
341 WARN_ON_ONCE(cpuc->enabled);
343 if (x86_pmu.intel_cap.pebs_trap)
344 intel_pmu_lbr_enable(event);
347 static void intel_pmu_pebs_disable(struct perf_event *event)
349 struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
350 struct hw_perf_event *hwc = &event->hw;
351 u64 val = cpuc->pebs_enabled;
353 val &= ~(1ULL << hwc->idx);
355 wrmsrl(MSR_IA32_PEBS_ENABLE, val);
357 hwc->config |= ARCH_PERFMON_EVENTSEL_INT;
359 if (x86_pmu.intel_cap.pebs_trap)
360 intel_pmu_lbr_disable(event);
363 static void intel_pmu_pebs_enable_all(void)
365 struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
367 if (cpuc->pebs_enabled)
368 wrmsrl(MSR_IA32_PEBS_ENABLE, cpuc->pebs_enabled);
371 static void intel_pmu_pebs_disable_all(void)
373 struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
375 if (cpuc->pebs_enabled)
376 wrmsrl(MSR_IA32_PEBS_ENABLE, 0);
379 #include <asm/insn.h>
381 static inline bool kernel_ip(unsigned long ip)
384 return ip > PAGE_OFFSET;
390 static int intel_pmu_pebs_fixup_ip(struct pt_regs *regs)
392 struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
393 unsigned long from = cpuc->lbr_entries[0].from;
394 unsigned long old_to, to = cpuc->lbr_entries[0].to;
395 unsigned long ip = regs->ip;
398 * We don't need to fixup if the PEBS assist is fault like
400 if (!x86_pmu.intel_cap.pebs_trap)
404 * No LBR entry, no basic block, no rewinding
406 if (!cpuc->lbr_stack.nr || !from || !to)
410 * Basic blocks should never cross user/kernel boundaries
412 if (kernel_ip(ip) != kernel_ip(to))
416 * unsigned math, either ip is before the start (impossible) or
417 * the basic block is larger than 1 page (sanity)
419 if ((ip - to) > PAGE_SIZE)
423 * We sampled a branch insn, rewind using the LBR stack
432 u8 buf[MAX_INSN_SIZE];
436 if (!kernel_ip(ip)) {
437 int bytes, size = MAX_INSN_SIZE;
439 bytes = copy_from_user_nmi(buf, (void __user *)to, size);
447 kernel_insn_init(&insn, kaddr);
448 insn_get_length(&insn);
458 * Even though we decoded the basic block, the instruction stream
459 * never matched the given IP, either the TO or the IP got corrupted.
464 static int intel_pmu_save_and_restart(struct perf_event *event);
466 static void intel_pmu_drain_pebs_core(struct pt_regs *iregs)
468 struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
469 struct debug_store *ds = cpuc->ds;
470 struct perf_event *event = cpuc->events[0]; /* PMC0 only */
471 struct pebs_record_core *at, *top;
472 struct perf_sample_data data;
473 struct perf_raw_record raw;
477 if (!event || !ds || !x86_pmu.pebs)
480 at = (struct pebs_record_core *)(unsigned long)ds->pebs_buffer_base;
481 top = (struct pebs_record_core *)(unsigned long)ds->pebs_index;
486 ds->pebs_index = ds->pebs_buffer_base;
488 if (!intel_pmu_save_and_restart(event))
491 perf_sample_data_init(&data, 0);
492 data.period = event->hw.last_period;
494 if (event->attr.sample_type & PERF_SAMPLE_RAW) {
495 raw.size = x86_pmu.pebs_record_size;
503 * Should not happen, we program the threshold at 1 and do not
509 * We use the interrupt regs as a base because the PEBS record
510 * does not contain a full regs set, specifically it seems to
511 * lack segment descriptors, which get used by things like
514 * In the simple case fix up only the IP and BP,SP regs, for
515 * PERF_SAMPLE_IP and PERF_SAMPLE_CALLCHAIN to function properly.
516 * A possible PERF_SAMPLE_REGS will have to transfer all regs.
523 if (intel_pmu_pebs_fixup_ip(®s))
524 regs.flags |= PERF_EFLAGS_EXACT;
526 regs.flags &= ~PERF_EFLAGS_EXACT;
528 if (perf_event_overflow(event, 1, &data, ®s))
532 static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs)
534 struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
535 struct debug_store *ds = cpuc->ds;
536 struct pebs_record_nhm *at, *top;
537 struct perf_sample_data data;
538 struct perf_event *event = NULL;
539 struct perf_raw_record raw;
543 if (!ds || !x86_pmu.pebs)
546 at = (struct pebs_record_nhm *)(unsigned long)ds->pebs_buffer_base;
547 top = (struct pebs_record_nhm *)(unsigned long)ds->pebs_index;
552 ds->pebs_index = ds->pebs_buffer_base;
557 * Should not happen, we program the threshold at 1 and do not
560 WARN_ON_ONCE(n > MAX_PEBS_EVENTS);
562 for ( ; at < top; at++) {
563 for_each_bit(bit, (unsigned long *)&at->status, MAX_PEBS_EVENTS) {
564 if (!cpuc->events[bit]->attr.precise)
567 event = cpuc->events[bit];
573 if (!intel_pmu_save_and_restart(event))
576 perf_sample_data_init(&data, 0);
577 data.period = event->hw.last_period;
579 if (event->attr.sample_type & PERF_SAMPLE_RAW) {
580 raw.size = x86_pmu.pebs_record_size;
586 * See the comment in intel_pmu_drain_pebs_core()
593 if (intel_pmu_pebs_fixup_ip(®s))
594 regs.flags |= PERF_EFLAGS_EXACT;
596 regs.flags &= ~PERF_EFLAGS_EXACT;
598 if (perf_event_overflow(event, 1, &data, ®s))
604 * BTS, PEBS probe and setup
607 static void intel_ds_init(void)
610 * No support for 32bit formats
612 if (!boot_cpu_has(X86_FEATURE_DTES64))
615 x86_pmu.bts = boot_cpu_has(X86_FEATURE_BTS);
616 x86_pmu.pebs = boot_cpu_has(X86_FEATURE_PEBS);
618 char pebs_type = x86_pmu.intel_cap.pebs_trap ? '+' : '-';
619 int format = x86_pmu.intel_cap.pebs_format;
623 printk(KERN_CONT "PEBS fmt0%c, ", pebs_type);
624 x86_pmu.pebs_record_size = sizeof(struct pebs_record_core);
625 x86_pmu.drain_pebs = intel_pmu_drain_pebs_core;
626 x86_pmu.pebs_constraints = intel_core_pebs_events;
630 printk(KERN_CONT "PEBS fmt1%c, ", pebs_type);
631 x86_pmu.pebs_record_size = sizeof(struct pebs_record_nhm);
632 x86_pmu.drain_pebs = intel_pmu_drain_pebs_nhm;
633 x86_pmu.pebs_constraints = intel_nehalem_pebs_events;
637 printk(KERN_CONT "no PEBS fmt%d%c, ", format, pebs_type);
644 #else /* CONFIG_CPU_SUP_INTEL */
646 static int reseve_ds_buffers(void)
651 static void release_ds_buffers(void)
655 #endif /* CONFIG_CPU_SUP_INTEL */