perf_event.c
/* Performance event support for sparc64.
*
* Copyright (C) 2009, 2010 David S. Miller <davem@davemloft.net>
*
* This code is based almost entirely upon the x86 perf event
* code, which is:
*
* Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de>
* Copyright (C) 2008-2009 Red Hat, Inc., Ingo Molnar
* Copyright (C) 2009 Jaswinder Singh Rajput
* Copyright (C) 2009 Advanced Micro Devices, Inc., Robert Richter
* Copyright (C) 2008-2009 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
*/
#include <linux/perf_event.h>
#include <linux/kprobes.h>
#include <linux/kernel.h>
#include <linux/kdebug.h>
#include <linux/mutex.h>
#include <asm/stacktrace.h>
#include <asm/cpudata.h>
#include <asm/uaccess.h>
#include <asm/atomic.h>
#include <asm/nmi.h>
#include <asm/pcr.h>
#include "kstack.h"
/* Sparc64 chips have two performance counters, 32-bits each, with
* overflow interrupts generated on transition from 0xffffffff to 0.
* The counters are accessed in one go using a 64-bit register.
*
* Both counters are controlled using a single control register. The
* only way to stop all sampling is to clear all of the context (user,
* supervisor, hypervisor) sampling enable bits. But these bits apply
* to both counters, thus the two counters can't be enabled/disabled
* individually.
*
* The control register has two event fields, one for each of the two
* counters. It's thus nearly impossible to have one counter going
* while keeping the other one stopped. Therefore it is possible to
* get overflow interrupts for counters not currently "in use" and
* that condition must be checked in the overflow interrupt handler.
*
* So we use a hack, in that we program inactive counters with the
* "sw_count0" and "sw_count1" events. These count how many times
* the instruction "sethi %hi(0xfc000), %g0" is executed. It's an
* unusual way to encode a NOP and therefore will not trigger in
* normal code.
*/
#define MAX_HWEVENTS 2
#define MAX_PERIOD ((1UL << 32) - 1)
#define PIC_UPPER_INDEX 0
#define PIC_LOWER_INDEX 1
#define PIC_NO_INDEX -1
struct cpu_hw_events {
/* Number of events currently scheduled onto this cpu.
* This tells how many entries in the arrays below
* are valid.
*/
int n_events;
/* Number of new events added since the last hw_perf_disable().
* This works because the perf event layer always adds new
* events inside of a perf_{disable,enable}() sequence.
*/
int n_added;
/* Array of events current scheduled on this cpu. */
struct perf_event *event[MAX_HWEVENTS];
/* Array of encoded longs, specifying the %pcr register
* encoding and the mask of PIC counters this even can
* be scheduled on. See perf_event_encode() et al.
*/
unsigned long events[MAX_HWEVENTS];
/* The current counter index assigned to an event. When the
* event hasn't been programmed into the cpu yet, this will
* hold PIC_NO_INDEX. The event->hw.idx value tells us where
* we ought to schedule the event.
*/
int current_idx[MAX_HWEVENTS];
/* Software copy of %pcr register on this cpu. */
u64 pcr;
/* Enabled/disable state. */
int enabled;
};
DEFINE_PER_CPU(struct cpu_hw_events, cpu_hw_events) = { .enabled = 1, };
/* An event map describes the characteristics of a performance
* counter event. In particular it gives the encoding as well as
* a mask telling which counters the event can be measured on.
*/
struct perf_event_map {
u16 encoding;
u8 pic_mask;
#define PIC_NONE 0x00
#define PIC_UPPER 0x01
#define PIC_LOWER 0x02
};
/* Encode a perf_event_map entry into a long. */
static unsigned long perf_event_encode(const struct perf_event_map *pmap)
{
return ((unsigned long) pmap->encoding << 16) | pmap->pic_mask;
}
static u8 perf_event_get_msk(unsigned long val)
{
return val & 0xff;
}
static u64 perf_event_get_enc(unsigned long val)
{
return val >> 16;
}
#define C(x) PERF_COUNT_HW_CACHE_##x
#define CACHE_OP_UNSUPPORTED 0xfffe
#define CACHE_OP_NONSENSE 0xffff
typedef struct perf_event_map cache_map_t
[PERF_COUNT_HW_CACHE_MAX]
[PERF_COUNT_HW_CACHE_OP_MAX]
[PERF_COUNT_HW_CACHE_RESULT_MAX];
struct sparc_pmu {
const struct perf_event_map *(*event_map)(int);
const cache_map_t *cache_map;
int max_events;
int upper_shift;
int lower_shift;
int event_mask;
int hv_bit;
int irq_bit;
int upper_nop;
int lower_nop;
};
static const struct perf_event_map ultra3_perfmon_event_map[] = {
[PERF_COUNT_HW_CPU_CYCLES] = { 0x0000, PIC_UPPER | PIC_LOWER },
[PERF_COUNT_HW_INSTRUCTIONS] = { 0x0001, PIC_UPPER | PIC_LOWER },
[PERF_COUNT_HW_CACHE_REFERENCES] = { 0x0009, PIC_LOWER },
[PERF_COUNT_HW_CACHE_MISSES] = { 0x0009, PIC_UPPER },
};
static const struct perf_event_map *ultra3_event_map(int event_id)
{
return &ultra3_perfmon_event_map[event_id];
}
static const cache_map_t ultra3_cache_map = {
[C(L1D)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = { 0x09, PIC_LOWER, },
[C(RESULT_MISS)] = { 0x09, PIC_UPPER, },
},
[C(OP_WRITE)] = {
[C(RESULT_ACCESS)] = { 0x0a, PIC_LOWER },
[C(RESULT_MISS)] = { 0x0a, PIC_UPPER },
},
[C(OP_PREFETCH)] = {
[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
[C(RESULT_MISS)] = { CACHE_OP_UNSUPPORTED },
},
},
[C(L1I)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = { 0x09, PIC_LOWER, },
[C(RESULT_MISS)] = { 0x09, PIC_UPPER, },
},
[ C(OP_WRITE) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_NONSENSE },
[ C(RESULT_MISS) ] = { CACHE_OP_NONSENSE },
},
[ C(OP_PREFETCH) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
[ C(RESULT_MISS) ] = { CACHE_OP_UNSUPPORTED },
},
},
[C(LL)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = { 0x0c, PIC_LOWER, },
[C(RESULT_MISS)] = { 0x0c, PIC_UPPER, },
},
[C(OP_WRITE)] = {
[C(RESULT_ACCESS)] = { 0x0c, PIC_LOWER },
[C(RESULT_MISS)] = { 0x0c, PIC_UPPER },
},
[C(OP_PREFETCH)] = {
[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
[C(RESULT_MISS)] = { CACHE_OP_UNSUPPORTED },
},
},
[C(DTLB)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
[C(RESULT_MISS)] = { 0x12, PIC_UPPER, },
},
[ C(OP_WRITE) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
[ C(RESULT_MISS) ] = { CACHE_OP_UNSUPPORTED },
},
[ C(OP_PREFETCH) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
[ C(RESULT_MISS) ] = { CACHE_OP_UNSUPPORTED },
},
},
[C(ITLB)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
[C(RESULT_MISS)] = { 0x11, PIC_UPPER, },
},
[ C(OP_WRITE) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
[ C(RESULT_MISS) ] = { CACHE_OP_UNSUPPORTED },
},
[ C(OP_PREFETCH) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
[ C(RESULT_MISS) ] = { CACHE_OP_UNSUPPORTED },
},
},
[C(BPU)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
[C(RESULT_MISS)] = { CACHE_OP_UNSUPPORTED },
},
[ C(OP_WRITE) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
[ C(RESULT_MISS) ] = { CACHE_OP_UNSUPPORTED },
},
[ C(OP_PREFETCH) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
[ C(RESULT_MISS) ] = { CACHE_OP_UNSUPPORTED },
},
},
};
static const struct sparc_pmu ultra3_pmu = {
.event_map = ultra3_event_map,
.cache_map = &ultra3_cache_map,
.max_events = ARRAY_SIZE(ultra3_perfmon_event_map),
.upper_shift = 11,
.lower_shift = 4,
.event_mask = 0x3f,
.upper_nop = 0x1c,
.lower_nop = 0x14,
};
/* Niagara1 is very limited. The upper PIC is hard-locked to count
* only instructions, so it is free running which creates all kinds of
* problems. Some hardware designs make one wonder if the creator
* even looked at how this stuff gets used by software.
*/
static const struct perf_event_map niagara1_perfmon_event_map[] = {
[PERF_COUNT_HW_CPU_CYCLES] = { 0x00, PIC_UPPER },
[PERF_COUNT_HW_INSTRUCTIONS] = { 0x00, PIC_UPPER },
[PERF_COUNT_HW_CACHE_REFERENCES] = { 0, PIC_NONE },
[PERF_COUNT_HW_CACHE_MISSES] = { 0x03, PIC_LOWER },
};
static const struct perf_event_map *niagara1_event_map(int event_id)
{
return &niagara1_perfmon_event_map[event_id];
}
static const cache_map_t niagara1_cache_map = {
[C(L1D)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
[C(RESULT_MISS)] = { 0x03, PIC_LOWER, },
},
[C(OP_WRITE)] = {
[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
[C(RESULT_MISS)] = { 0x03, PIC_LOWER, },
},
[C(OP_PREFETCH)] = {
[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
[C(RESULT_MISS)] = { CACHE_OP_UNSUPPORTED },
},
},
[C(L1I)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = { 0x00, PIC_UPPER },
[C(RESULT_MISS)] = { 0x02, PIC_LOWER, },
},
[ C(OP_WRITE) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_NONSENSE },
[ C(RESULT_MISS) ] = { CACHE_OP_NONSENSE },
},
[ C(OP_PREFETCH) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
[ C(RESULT_MISS) ] = { CACHE_OP_UNSUPPORTED },
},
},
[C(LL)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
[C(RESULT_MISS)] = { 0x07, PIC_LOWER, },
},
[C(OP_WRITE)] = {
[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
[C(RESULT_MISS)] = { 0x07, PIC_LOWER, },
},
[C(OP_PREFETCH)] = {
[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
[C(RESULT_MISS)] = { CACHE_OP_UNSUPPORTED },
},
},
[C(DTLB)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
[C(RESULT_MISS)] = { 0x05, PIC_LOWER, },
},
[ C(OP_WRITE) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
[ C(RESULT_MISS) ] = { CACHE_OP_UNSUPPORTED },
},
[ C(OP_PREFETCH) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
[ C(RESULT_MISS) ] = { CACHE_OP_UNSUPPORTED },
},
},
[C(ITLB)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
[C(RESULT_MISS)] = { 0x04, PIC_LOWER, },
},
[ C(OP_WRITE) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
[ C(RESULT_MISS) ] = { CACHE_OP_UNSUPPORTED },
},
[ C(OP_PREFETCH) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
[ C(RESULT_MISS) ] = { CACHE_OP_UNSUPPORTED },
},
},
[C(BPU)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
[C(RESULT_MISS)] = { CACHE_OP_UNSUPPORTED },
},
[ C(OP_WRITE) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
[ C(RESULT_MISS) ] = { CACHE_OP_UNSUPPORTED },
},
[ C(OP_PREFETCH) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
[ C(RESULT_MISS) ] = { CACHE_OP_UNSUPPORTED },
},
},
};
static const struct sparc_pmu niagara1_pmu = {
.event_map = niagara1_event_map,
.cache_map = &niagara1_cache_map,
.max_events = ARRAY_SIZE(niagara1_perfmon_event_map),
.upper_shift = 0,
.lower_shift = 4,
.event_mask = 0x7,
.upper_nop = 0x0,
.lower_nop = 0x0,
};
static const struct perf_event_map niagara2_perfmon_event_map[] = {
[PERF_COUNT_HW_CPU_CYCLES] = { 0x02ff, PIC_UPPER | PIC_LOWER },
[PERF_COUNT_HW_INSTRUCTIONS] = { 0x02ff, PIC_UPPER | PIC_LOWER },
[PERF_COUNT_HW_CACHE_REFERENCES] = { 0x0208, PIC_UPPER | PIC_LOWER },
[PERF_COUNT_HW_CACHE_MISSES] = { 0x0302, PIC_UPPER | PIC_LOWER },
[PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = { 0x0201, PIC_UPPER | PIC_LOWER },
[PERF_COUNT_HW_BRANCH_MISSES] = { 0x0202, PIC_UPPER | PIC_LOWER },
};
static const struct perf_event_map *niagara2_event_map(int event_id)
{
return &niagara2_perfmon_event_map[event_id];
}
static const cache_map_t niagara2_cache_map = {
[C(L1D)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = { 0x0208, PIC_UPPER | PIC_LOWER, },
[C(RESULT_MISS)] = { 0x0302, PIC_UPPER | PIC_LOWER, },
},
[C(OP_WRITE)] = {
[C(RESULT_ACCESS)] = { 0x0210, PIC_UPPER | PIC_LOWER, },
[C(RESULT_MISS)] = { 0x0302, PIC_UPPER | PIC_LOWER, },
},
[C(OP_PREFETCH)] = {
[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
[C(RESULT_MISS)] = { CACHE_OP_UNSUPPORTED },
},
},
[C(L1I)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = { 0x02ff, PIC_UPPER | PIC_LOWER, },
[C(RESULT_MISS)] = { 0x0301, PIC_UPPER | PIC_LOWER, },
},
[ C(OP_WRITE) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_NONSENSE },
[ C(RESULT_MISS) ] = { CACHE_OP_NONSENSE },
},
[ C(OP_PREFETCH) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
[ C(RESULT_MISS) ] = { CACHE_OP_UNSUPPORTED },
},
},
[C(LL)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = { 0x0208, PIC_UPPER | PIC_LOWER, },
[C(RESULT_MISS)] = { 0x0330, PIC_UPPER | PIC_LOWER, },
},
[C(OP_WRITE)] = {
[C(RESULT_ACCESS)] = { 0x0210, PIC_UPPER | PIC_LOWER, },
[C(RESULT_MISS)] = { 0x0320, PIC_UPPER | PIC_LOWER, },
},
[C(OP_PREFETCH)] = {
[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
[C(RESULT_MISS)] = { CACHE_OP_UNSUPPORTED },
},
},
[C(DTLB)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
[C(RESULT_MISS)] = { 0x0b08, PIC_UPPER | PIC_LOWER, },
},
[ C(OP_WRITE) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
[ C(RESULT_MISS) ] = { CACHE_OP_UNSUPPORTED },
},
[ C(OP_PREFETCH) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
[ C(RESULT_MISS) ] = { CACHE_OP_UNSUPPORTED },
},
},
[C(ITLB)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
[C(RESULT_MISS)] = { 0xb04, PIC_UPPER | PIC_LOWER, },
},
[ C(OP_WRITE) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
[ C(RESULT_MISS) ] = { CACHE_OP_UNSUPPORTED },
},
[ C(OP_PREFETCH) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
[ C(RESULT_MISS) ] = { CACHE_OP_UNSUPPORTED },
},
},
[C(BPU)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
[C(RESULT_MISS)] = { CACHE_OP_UNSUPPORTED },
},
[ C(OP_WRITE) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
[ C(RESULT_MISS) ] = { CACHE_OP_UNSUPPORTED },
},
[ C(OP_PREFETCH) ] = {
[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
[ C(RESULT_MISS) ] = { CACHE_OP_UNSUPPORTED },
},
},
};
static const struct sparc_pmu niagara2_pmu = {
.event_map = niagara2_event_map,
.cache_map = &niagara2_cache_map,
.max_events = ARRAY_SIZE(niagara2_perfmon_event_map),
.upper_shift = 19,
.lower_shift = 6,
.event_mask = 0xfff,
.hv_bit = 0x8,
.irq_bit = 0x30,
.upper_nop = 0x220,
.lower_nop = 0x220,
};
static const struct sparc_pmu *sparc_pmu __read_mostly;
static u64 event_encoding(u64 event_id, int idx)
{
if (idx == PIC_UPPER_INDEX)
event_id <<= sparc_pmu->upper_shift;
else
event_id <<= sparc_pmu->lower_shift;
return event_id;
}
static u64 mask_for_index(int idx)
{
return event_encoding(sparc_pmu->event_mask, idx);
}
static u64 nop_for_index(int idx)
{
return event_encoding(idx == PIC_UPPER_INDEX ?
sparc_pmu->upper_nop :
sparc_pmu->lower_nop, idx);
}
static inline void sparc_pmu_enable_event(struct cpu_hw_events *cpuc, struct hw_perf_event *hwc, int idx)
{
u64 val, mask = mask_for_index(idx);
val = cpuc->pcr;
val &= ~mask;
val |= hwc->config;
cpuc->pcr = val;
pcr_ops->write(cpuc->pcr);
}
static inline void sparc_pmu_disable_event(struct cpu_hw_events *cpuc, struct hw_perf_event *hwc, int idx)
{
u64 mask = mask_for_index(idx);
u64 nop = nop_for_index(idx);
u64 val;
val = cpuc->pcr;
val &= ~mask;
val |= nop;
cpuc->pcr = val;
pcr_ops->write(cpuc->pcr);
}
static u32 read_pmc(int idx)
{
u64 val;
read_pic(val);
if (idx == PIC_UPPER_INDEX)
val >>= 32;
return val & 0xffffffff;
}
static void write_pmc(int idx, u64 val)
{
u64 shift, mask, pic;
shift = 0;
if (idx == PIC_UPPER_INDEX)
shift = 32;
mask = ((u64) 0xffffffff) << shift;
val <<= shift;
read_pic(pic);
pic &= ~mask;
pic |= val;
write_pic(pic);
}
static u64 sparc_perf_event_update(struct perf_event *event,
struct hw_perf_event *hwc, int idx)
{
int shift = 64 - 32;
u64 prev_raw_count, new_raw_count;
s64 delta;
again:
prev_raw_count = atomic64_read(&hwc->prev_count);
new_raw_count = read_pmc(idx);
if (atomic64_cmpxchg(&hwc->prev_count, prev_raw_count,
new_raw_count) != prev_raw_count)
goto again;
delta = (new_raw_count << shift) - (prev_raw_count << shift);
delta >>= shift;
atomic64_add(delta, &event->count);
atomic64_sub(delta, &hwc->period_left);
return new_raw_count;
}
static int sparc_perf_event_set_period(struct perf_event *event,
struct hw_perf_event *hwc, int idx)
{
s64 left = atomic64_read(&hwc->period_left);
s64 period = hwc->sample_period;
int ret = 0;
if (unlikely(left <= -period)) {
left = period;
atomic64_set(&hwc->period_left, left);
hwc->last_period = period;
ret = 1;
}
if (unlikely(left <= 0)) {
left += period;
atomic64_set(&hwc->period_left, left);
hwc->last_period = period;
ret = 1;
}
if (left > MAX_PERIOD)
left = MAX_PERIOD;
atomic64_set(&hwc->prev_count, (u64)-left);
write_pmc(idx, (u64)(-left) & 0xffffffff);
perf_event_update_userpage(event);
return ret;
}
/* If performance event entries have been added, move existing
* events around (if necessary) and then assign new entries to
* counters.
*/
static u64 maybe_change_configuration(struct cpu_hw_events *cpuc, u64 pcr)
{
int i;
if (!cpuc->n_added)
goto out;
/* Read in the counters which are moving. */
for (i = 0; i < cpuc->n_events; i++) {
struct perf_event *cp = cpuc->event[i];
if (cpuc->current_idx[i] != PIC_NO_INDEX &&
cpuc->current_idx[i] != cp->hw.idx) {
sparc_perf_event_update(cp, &cp->hw,
cpuc->current_idx[i]);
cpuc->current_idx[i] = PIC_NO_INDEX;
}
}
/* Assign to counters all unassigned events. */
for (i = 0; i < cpuc->n_events; i++) {
struct perf_event *cp = cpuc->event[i];
struct hw_perf_event *hwc = &cp->hw;
int idx = hwc->idx;
u64 enc;
if (cpuc->current_idx[i] != PIC_NO_INDEX)
continue;
sparc_perf_event_set_period(cp, hwc, idx);
cpuc->current_idx[i] = idx;
enc = perf_event_get_enc(cpuc->events[i]);
pcr |= event_encoding(enc, idx);
}
out:
return pcr;
}
void hw_perf_enable(void)
{
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
u64 pcr;
if (cpuc->enabled)
return;
cpuc->enabled = 1;
barrier();
pcr = cpuc->pcr;
if (!cpuc->n_events) {
pcr = 0;
} else {
pcr = maybe_change_configuration(cpuc, pcr);
/* We require that all of the events have the same
* configuration, so just fetch the settings from the
* first entry.
*/
cpuc->pcr = pcr | cpuc->event[0]->hw.config_base;
}
pcr_ops->write(cpuc->pcr);
}
void hw_perf_disable(void)
{
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
u64 val;
if (!cpuc->enabled)
return;
cpuc->enabled = 0;
cpuc->n_added = 0;
val = cpuc->pcr;
val &= ~(PCR_UTRACE | PCR_STRACE |
sparc_pmu->hv_bit | sparc_pmu->irq_bit);
cpuc->pcr = val;
pcr_ops->write(cpuc->pcr);
}
static void sparc_pmu_disable(struct perf_event *event)
{
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
struct hw_perf_event *hwc = &event->hw;
unsigned long flags;
int i;
local_irq_save(flags);
perf_disable();
for (i = 0; i < cpuc->n_events; i++) {
if (event == cpuc->event[i]) {
int idx = cpuc->current_idx[i];
/* Shift remaining entries down into
* the existing slot.
*/
while (++i < cpuc->n_events) {
cpuc->event[i - 1] = cpuc->event[i];
cpuc->events[i - 1] = cpuc->events[i];
cpuc->current_idx[i - 1] =
cpuc->current_idx[i];
}
/* Absorb the final count and turn off the
* event.
*/
sparc_pmu_disable_event(cpuc, hwc, idx);
barrier();
sparc_perf_event_update(event, hwc, idx);
perf_event_update_userpage(event);
cpuc->n_events--;
break;
}
}
perf_enable();
local_irq_restore(flags);
}
static int active_event_index(struct cpu_hw_events *cpuc,
struct perf_event *event)
{
int i;
for (i = 0; i < cpuc->n_events; i++) {
if (cpuc->event[i] == event)
break;
}
BUG_ON(i == cpuc->n_events);
return cpuc->current_idx[i];
}
static void sparc_pmu_read(struct perf_event *event)
{
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
int idx = active_event_index(cpuc, event);
struct hw_perf_event *hwc = &event->hw;
sparc_perf_event_update(event, hwc, idx);
}
static void sparc_pmu_unthrottle(struct perf_event *event)
{
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
int idx = active_event_index(cpuc, event);
struct hw_perf_event *hwc = &event->hw;
sparc_pmu_enable_event(cpuc, hwc, idx);
}
static atomic_t active_events = ATOMIC_INIT(0);
static DEFINE_MUTEX(pmc_grab_mutex);
static void perf_stop_nmi_watchdog(void *unused)
{
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
stop_nmi_watchdog(NULL);
cpuc->pcr = pcr_ops->read();
}
void perf_event_grab_pmc(void)
{
if (atomic_inc_not_zero(&active_events))
return;
mutex_lock(&pmc_grab_mutex);
if (atomic_read(&active_events) == 0) {
if (atomic_read(&nmi_active) > 0) {
on_each_cpu(perf_stop_nmi_watchdog, NULL, 1);
BUG_ON(atomic_read(&nmi_active) != 0);
}
atomic_inc(&active_events);
}
mutex_unlock(&pmc_grab_mutex);
}
void perf_event_release_pmc(void)
{
if (atomic_dec_and_mutex_lock(&active_events, &pmc_grab_mutex)) {
if (atomic_read(&nmi_active) == 0)
on_each_cpu(start_nmi_watchdog, NULL, 1);
mutex_unlock(&pmc_grab_mutex);
}
}
static const struct perf_event_map *sparc_map_cache_event(u64 config)
{
unsigned int cache_type, cache_op, cache_result;
const struct perf_event_map *pmap;
if (!sparc_pmu->cache_map)
return ERR_PTR(-ENOENT);
cache_type = (config >> 0) & 0xff;
if (cache_type >= PERF_COUNT_HW_CACHE_MAX)
return ERR_PTR(-EINVAL);
cache_op = (config >> 8) & 0xff;
if (cache_op >= PERF_COUNT_HW_CACHE_OP_MAX)
return ERR_PTR(-EINVAL);
cache_result = (config >> 16) & 0xff;
if (cache_result >= PERF_COUNT_HW_CACHE_RESULT_MAX)
return ERR_PTR(-EINVAL);
pmap = &((*sparc_pmu->cache_map)[cache_type][cache_op][cache_result]);
if (pmap->encoding == CACHE_OP_UNSUPPORTED)
return ERR_PTR(-ENOENT);
if (pmap->encoding == CACHE_OP_NONSENSE)
return ERR_PTR(-EINVAL);
return pmap;
}
static void hw_perf_event_destroy(struct perf_event *event)
{
perf_event_release_pmc();
}
/* Make sure all events can be scheduled into the hardware at
* the same time. This is simplified by the fact that we only
* need to support 2 simultaneous HW events.
*
* As a side effect, the evts[]->hw.idx values will be assigned
* on success. These are pending indexes. When the events are
* actually programmed into the chip, these values will propagate
* to the per-cpu cpuc->current_idx[] slots, see the code in
* maybe_change_configuration() for details.
*/
static int sparc_check_constraints(struct perf_event **evts,
unsigned long *events, int n_ev)
{
u8 msk0 = 0, msk1 = 0;
int idx0 = 0;
/* This case is possible when we are invoked from
* hw_perf_group_sched_in().
*/
if (!n_ev)
return 0;
if (n_ev > perf_max_events)
return -1;
msk0 = perf_event_get_msk(events[0]);
if (n_ev == 1) {
if (msk0 & PIC_LOWER)
idx0 = 1;
goto success;
}
BUG_ON(n_ev != 2);
msk1 = perf_event_get_msk(events[1]);
/* If both events can go on any counter, OK. */
if (msk0 == (PIC_UPPER | PIC_LOWER) &&
msk1 == (PIC_UPPER | PIC_LOWER))
goto success;
/* If one event is limited to a specific counter,
* and the other can go on both, OK.
*/
if ((msk0 == PIC_UPPER || msk0 == PIC_LOWER) &&
msk1 == (PIC_UPPER | PIC_LOWER)) {
if (msk0 & PIC_LOWER)
idx0 = 1;
goto success;
}
if ((msk1 == PIC_UPPER || msk1 == PIC_LOWER) &&
msk0 == (PIC_UPPER | PIC_LOWER)) {
if (msk1 & PIC_UPPER)
idx0 = 1;
goto success;
}
/* If the events are fixed to different counters, OK. */
if ((msk0 == PIC_UPPER && msk1 == PIC_LOWER) ||
(msk0 == PIC_LOWER && msk1 == PIC_UPPER)) {
if (msk0 & PIC_LOWER)
idx0 = 1;
goto success;
}
/* Otherwise, there is a conflict. */
return -1;
success:
evts[0]->hw.idx = idx0;
if (n_ev == 2)
evts[1]->hw.idx = idx0 ^ 1;
return 0;
}
static int check_excludes(struct perf_event **evts, int n_prev, int n_new)
{
int eu = 0, ek = 0, eh = 0;
struct perf_event *event;
int i, n, first;
n = n_prev + n_new;
if (n <= 1)
return 0;
first = 1;
for (i = 0; i < n; i++) {
event = evts[i];
if (first) {
eu = event->attr.exclude_user;
ek = event->attr.exclude_kernel;
eh = event->attr.exclude_hv;
first = 0;
} else if (event->attr.exclude_user != eu ||
event->attr.exclude_kernel != ek ||
event->attr.exclude_hv != eh) {
return -EAGAIN;
}
}
return 0;
}
static int collect_events(struct perf_event *group, int max_count,
struct perf_event *evts[], unsigned long *events,
int *current_idx)
{
struct perf_event *event;
int n = 0;
if (!is_software_event(group)) {
if (n >= max_count)
return -1;
evts[n] = group;
events[n] = group->hw.event_base;
current_idx[n++] = PIC_NO_INDEX;
}
list_for_each_entry(event, &group->sibling_list, group_entry) {
if (!is_software_event(event) &&
event->state != PERF_EVENT_STATE_OFF) {
if (n >= max_count)
return -1;
evts[n] = event;
events[n] = event->hw.event_base;
current_idx[n++] = PIC_NO_INDEX;
}
}
return n;
}
static void event_sched_in(struct perf_event *event, int cpu)
{
event->state = PERF_EVENT_STATE_ACTIVE;
event->oncpu = cpu;
event->tstamp_running += event->ctx->time - event->tstamp_stopped;
if (is_software_event(event))
event->pmu->enable(event);
}
int hw_perf_group_sched_in(struct perf_event *group_leader,
struct perf_cpu_context *cpuctx,
struct perf_event_context *ctx, int cpu)
{
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
struct perf_event *sub;
int n0, n;
if (!sparc_pmu)
return 0;
n0 = cpuc->n_events;
n = collect_events(group_leader, perf_max_events - n0,
&cpuc->event[n0], &cpuc->events[n0],
&cpuc->current_idx[n0]);
if (n < 0)
return -EAGAIN;
if (check_excludes(cpuc->event, n0, n))
return -EINVAL;
if (sparc_check_constraints(cpuc->event, cpuc->events, n + n0))
return -EAGAIN;
cpuc->n_events = n0 + n;
cpuc->n_added += n;
cpuctx->active_oncpu += n;
n = 1;
event_sched_in(group_leader, cpu);
list_for_each_entry(sub, &group_leader->sibling_list, group_entry) {
if (sub->state != PERF_EVENT_STATE_OFF) {
event_sched_in(sub, cpu);
n++;
}
}
ctx->nr_active += n;
return 1;
}
static int sparc_pmu_enable(struct perf_event *event)
{
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
int n0, ret = -EAGAIN;
unsigned long flags;
local_irq_save(flags);
perf_disable();
n0 = cpuc->n_events;
if (n0 >= perf_max_events)
goto out;
cpuc->event[n0] = event;
cpuc->events[n0] = event->hw.event_base;
cpuc->current_idx[n0] = PIC_NO_INDEX;
if (check_excludes(cpuc->event, n0, 1))
goto out;
if (sparc_check_constraints(cpuc->event, cpuc->events, n0 + 1))
goto out;
cpuc->n_events++;
cpuc->n_added++;
ret = 0;
out:
perf_enable();
local_irq_restore(flags);
return ret;
}
static int __hw_perf_event_init(struct perf_event *event)
{
struct perf_event_attr *attr = &event->attr;
struct perf_event *evts[MAX_HWEVENTS];
struct hw_perf_event *hwc = &event->hw;
unsigned long events[MAX_HWEVENTS];
int current_idx_dmy[MAX_HWEVENTS];
const struct perf_event_map *pmap;
int n;
if (atomic_read(&nmi_active) < 0)
return -ENODEV;
if (attr->type == PERF_TYPE_HARDWARE) {
if (attr->config >= sparc_pmu->max_events)
return -EINVAL;
pmap = sparc_pmu->event_map(attr->config);
} else if (attr->type == PERF_TYPE_HW_CACHE) {
pmap = sparc_map_cache_event(attr->config);
if (IS_ERR(pmap))
return PTR_ERR(pmap);
} else
return -EOPNOTSUPP;
/* We save the enable bits in the config_base. */
hwc->config_base = sparc_pmu->irq_bit;
if (!attr->exclude_user)
hwc->config_base |= PCR_UTRACE;
if (!attr->exclude_kernel)
hwc->config_base |= PCR_STRACE;
if (!attr->exclude_hv)
hwc->config_base |= sparc_pmu->hv_bit;
hwc->event_base = perf_event_encode(pmap);
n = 0;
if (event->group_leader != event) {
n = collect_events(event->group_leader,
perf_max_events - 1,
evts, events, current_idx_dmy);
if (n < 0)
return -EINVAL;
}
events[n] = hwc->event_base;
evts[n] = event;
if (check_excludes(evts, n, 1))
return -EINVAL;
if (sparc_check_constraints(evts, events, n + 1))
return -EINVAL;
hwc->idx = PIC_NO_INDEX;
/* Try to do all error checking before this point, as unwinding
* state after grabbing the PMC is difficult.
*/
perf_event_grab_pmc();
event->destroy = hw_perf_event_destroy;
if (!hwc->sample_period) {
hwc->sample_period = MAX_PERIOD;
hwc->last_period = hwc->sample_period;
atomic64_set(&hwc->period_left, hwc->sample_period);
}
return 0;
}
static const struct pmu pmu = {
.enable = sparc_pmu_enable,
.disable = sparc_pmu_disable,
.read = sparc_pmu_read,
.unthrottle = sparc_pmu_unthrottle,
};
const struct pmu *hw_perf_event_init(struct perf_event *event)
{
int err = __hw_perf_event_init(event);
if (err)
return ERR_PTR(err);
return &pmu;
}
void perf_event_print_debug(void)
{
unsigned long flags;
u64 pcr, pic;
int cpu;
if (!sparc_pmu)
return;
local_irq_save(flags);
cpu = smp_processor_id();
pcr = pcr_ops->read();
read_pic(pic);
pr_info("\n");
pr_info("CPU#%d: PCR[%016llx] PIC[%016llx]\n",
cpu, pcr, pic);
local_irq_restore(flags);
}
static int __kprobes perf_event_nmi_handler(struct notifier_block *self,
unsigned long cmd, void *__args)
{
struct die_args *args = __args;
struct perf_sample_data data;
struct cpu_hw_events *cpuc;
struct pt_regs *regs;
int i;
if (!atomic_read(&active_events))
return NOTIFY_DONE;
switch (cmd) {
case DIE_NMI:
break;
default:
return NOTIFY_DONE;
}
regs = args->regs;
data.addr = 0;
cpuc = &__get_cpu_var(cpu_hw_events);
/* If the PMU has the TOE IRQ enable bits, we need to do a
* dummy write to the %pcr to clear the overflow bits and thus
* the interrupt.
*
* Do this before we peek at the counters to determine
* overflow so we don't lose any events.
*/
if (sparc_pmu->irq_bit)
pcr_ops->write(cpuc->pcr);
for (i = 0; i < cpuc->n_events; i++) {
struct perf_event *event = cpuc->event[i];
int idx = cpuc->current_idx[i];
struct hw_perf_event *hwc;
u64 val;
hwc = &event->hw;
val = sparc_perf_event_update(event, hwc, idx);
if (val & (1ULL << 31))
continue;
data.period = event->hw.last_period;
if (!sparc_perf_event_set_period(event, hwc, idx))
continue;
if (perf_event_overflow(event, 1, &data, regs))
sparc_pmu_disable_event(cpuc, hwc, idx);
}
return NOTIFY_STOP;
}
static __read_mostly struct notifier_block perf_event_nmi_notifier = {
.notifier_call = perf_event_nmi_handler,
};
static bool __init supported_pmu(void)
{
if (!strcmp(sparc_pmu_type, "ultra3") ||
!strcmp(sparc_pmu_type, "ultra3+") ||
!strcmp(sparc_pmu_type, "ultra3i") ||
!strcmp(sparc_pmu_type, "ultra4+")) {
sparc_pmu = &ultra3_pmu;
return true;
}
if (!strcmp(sparc_pmu_type, "niagara")) {
sparc_pmu = &niagara1_pmu;
return true;
}
if (!strcmp(sparc_pmu_type, "niagara2")) {
sparc_pmu = &niagara2_pmu;
return true;
}
return false;
}
void __init init_hw_perf_events(void)
{
pr_info("Performance events: ");
if (!supported_pmu()) {
pr_cont("No support for PMU type '%s'\n", sparc_pmu_type);
return;
}
pr_cont("Supported PMU type is '%s'\n", sparc_pmu_type);
/* All sparc64 PMUs currently have 2 events. */
perf_max_events = 2;
register_die_notifier(&perf_event_nmi_notifier);
}
static inline void callchain_store(struct perf_callchain_entry *entry, u64 ip)
{
if (entry->nr < PERF_MAX_STACK_DEPTH)
entry->ip[entry->nr++] = ip;
}
static void perf_callchain_kernel(struct pt_regs *regs,
struct perf_callchain_entry *entry)
{
unsigned long ksp, fp;
callchain_store(entry, PERF_CONTEXT_KERNEL);
callchain_store(entry, regs->tpc);
ksp = regs->u_regs[UREG_I6];
fp = ksp + STACK_BIAS;
do {
struct sparc_stackf *sf;
struct pt_regs *regs;
unsigned long pc;
if (!kstack_valid(current_thread_info(), fp))
break;
sf = (struct sparc_stackf *) fp;
regs = (struct pt_regs *) (sf + 1);
if (kstack_is_trap_frame(current_thread_info(), regs)) {
if (user_mode(regs))
break;
pc = regs->tpc;
fp = regs->u_regs[UREG_I6] + STACK_BIAS;
} else {
pc = sf->callers_pc;
fp = (unsigned long)sf->fp + STACK_BIAS;
}
callchain_store(entry, pc);
} while (entry->nr < PERF_MAX_STACK_DEPTH);
}
static void perf_callchain_user_64(struct pt_regs *regs,
struct perf_callchain_entry *entry)
{
unsigned long ufp;
callchain_store(entry, PERF_CONTEXT_USER);
callchain_store(entry, regs->tpc);
ufp = regs->u_regs[UREG_I6] + STACK_BIAS;
do {
struct sparc_stackf *usf, sf;
unsigned long pc;
usf = (struct sparc_stackf *) ufp;
if (__copy_from_user_inatomic(&sf, usf, sizeof(sf)))
break;
pc = sf.callers_pc;
ufp = (unsigned long)sf.fp + STACK_BIAS;
callchain_store(entry, pc);
} while (entry->nr < PERF_MAX_STACK_DEPTH);
}
static void perf_callchain_user_32(struct pt_regs *regs,
struct perf_callchain_entry *entry)
{
unsigned long ufp;
callchain_store(entry, PERF_CONTEXT_USER);
callchain_store(entry, regs->tpc);
ufp = regs->u_regs[UREG_I6];
do {
struct sparc_stackf32 *usf, sf;
unsigned long pc;
usf = (struct sparc_stackf32 *) ufp;
if (__copy_from_user_inatomic(&sf, usf, sizeof(sf)))
break;
pc = sf.callers_pc;
ufp = (unsigned long)sf.fp;
callchain_store(entry, pc);
} while (entry->nr < PERF_MAX_STACK_DEPTH);
}
/* Like powerpc we can't get PMU interrupts within the PMU handler,
* so no need for seperate NMI and IRQ chains as on x86.
*/
static DEFINE_PER_CPU(struct perf_callchain_entry, callchain);
struct perf_callchain_entry *perf_callchain(struct pt_regs *regs)
{
struct perf_callchain_entry *entry = &__get_cpu_var(callchain);
entry->nr = 0;
if (!user_mode(regs)) {
stack_trace_flush();
perf_callchain_kernel(regs, entry);
if (current->mm)
regs = task_pt_regs(current);
else
regs = NULL;
}
if (regs) {
flushw_user();
if (test_thread_flag(TIF_32BIT))
perf_callchain_user_32(regs, entry);
else
perf_callchain_user_64(regs, entry);
}
return entry;
}