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|
// SPDX-License-Identifier: GPL-2.0
#include <linux/bitops.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <asm/cpu_entry_area.h>
#include <asm/perf_event.h>
#include <asm/tlbflush.h>
#include <asm/insn.h>
#include "../perf_event.h"
/* Waste a full page so it can be mapped into the cpu_entry_area */
DEFINE_PER_CPU_PAGE_ALIGNED(struct debug_store, cpu_debug_store);
/* The size of a BTS record in bytes: */
#define BTS_RECORD_SIZE 24
#define PEBS_FIXUP_SIZE PAGE_SIZE
/*
* pebs_record_32 for p4 and core not supported
struct pebs_record_32 {
u32 flags, ip;
u32 ax, bc, cx, dx;
u32 si, di, bp, sp;
};
*/
union intel_x86_pebs_dse {
u64 val;
struct {
unsigned int ld_dse:4;
unsigned int ld_stlb_miss:1;
unsigned int ld_locked:1;
unsigned int ld_reserved:26;
};
struct {
unsigned int st_l1d_hit:1;
unsigned int st_reserved1:3;
unsigned int st_stlb_miss:1;
unsigned int st_locked:1;
unsigned int st_reserved2:26;
};
};
/*
* Map PEBS Load Latency Data Source encodings to generic
* memory data source information
*/
#define P(a, b) PERF_MEM_S(a, b)
#define OP_LH (P(OP, LOAD) | P(LVL, HIT))
#define LEVEL(x) P(LVLNUM, x)
#define REM P(REMOTE, REMOTE)
#define SNOOP_NONE_MISS (P(SNOOP, NONE) | P(SNOOP, MISS))
/* Version for Sandy Bridge and later */
static u64 pebs_data_source[] = {
P(OP, LOAD) | P(LVL, MISS) | LEVEL(L3) | P(SNOOP, NA),/* 0x00:ukn L3 */
OP_LH | P(LVL, L1) | LEVEL(L1) | P(SNOOP, NONE), /* 0x01: L1 local */
OP_LH | P(LVL, LFB) | LEVEL(LFB) | P(SNOOP, NONE), /* 0x02: LFB hit */
OP_LH | P(LVL, L2) | LEVEL(L2) | P(SNOOP, NONE), /* 0x03: L2 hit */
OP_LH | P(LVL, L3) | LEVEL(L3) | P(SNOOP, NONE), /* 0x04: L3 hit */
OP_LH | P(LVL, L3) | LEVEL(L3) | P(SNOOP, MISS), /* 0x05: L3 hit, snoop miss */
OP_LH | P(LVL, L3) | LEVEL(L3) | P(SNOOP, HIT), /* 0x06: L3 hit, snoop hit */
OP_LH | P(LVL, L3) | LEVEL(L3) | P(SNOOP, HITM), /* 0x07: L3 hit, snoop hitm */
OP_LH | P(LVL, REM_CCE1) | REM | LEVEL(L3) | P(SNOOP, HIT), /* 0x08: L3 miss snoop hit */
OP_LH | P(LVL, REM_CCE1) | REM | LEVEL(L3) | P(SNOOP, HITM), /* 0x09: L3 miss snoop hitm*/
OP_LH | P(LVL, LOC_RAM) | LEVEL(RAM) | P(SNOOP, HIT), /* 0x0a: L3 miss, shared */
OP_LH | P(LVL, REM_RAM1) | REM | LEVEL(L3) | P(SNOOP, HIT), /* 0x0b: L3 miss, shared */
OP_LH | P(LVL, LOC_RAM) | LEVEL(RAM) | SNOOP_NONE_MISS, /* 0x0c: L3 miss, excl */
OP_LH | P(LVL, REM_RAM1) | LEVEL(RAM) | REM | SNOOP_NONE_MISS, /* 0x0d: L3 miss, excl */
OP_LH | P(LVL, IO) | LEVEL(NA) | P(SNOOP, NONE), /* 0x0e: I/O */
OP_LH | P(LVL, UNC) | LEVEL(NA) | P(SNOOP, NONE), /* 0x0f: uncached */
};
/* Patch up minor differences in the bits */
void __init intel_pmu_pebs_data_source_nhm(void)
{
pebs_data_source[0x05] = OP_LH | P(LVL, L3) | LEVEL(L3) | P(SNOOP, HIT);
pebs_data_source[0x06] = OP_LH | P(LVL, L3) | LEVEL(L3) | P(SNOOP, HITM);
pebs_data_source[0x07] = OP_LH | P(LVL, L3) | LEVEL(L3) | P(SNOOP, HITM);
}
void __init intel_pmu_pebs_data_source_skl(bool pmem)
{
u64 pmem_or_l4 = pmem ? LEVEL(PMEM) : LEVEL(L4);
pebs_data_source[0x08] = OP_LH | pmem_or_l4 | P(SNOOP, HIT);
pebs_data_source[0x09] = OP_LH | pmem_or_l4 | REM | P(SNOOP, HIT);
pebs_data_source[0x0b] = OP_LH | LEVEL(RAM) | REM | P(SNOOP, NONE);
pebs_data_source[0x0c] = OP_LH | LEVEL(ANY_CACHE) | REM | P(SNOOPX, FWD);
pebs_data_source[0x0d] = OP_LH | LEVEL(ANY_CACHE) | REM | P(SNOOP, HITM);
}
static u64 precise_store_data(u64 status)
{
union intel_x86_pebs_dse dse;
u64 val = P(OP, STORE) | P(SNOOP, NA) | P(LVL, L1) | P(TLB, L2);
dse.val = status;
/*
* bit 4: TLB access
* 1 = stored missed 2nd level TLB
*
* so it either hit the walker or the OS
* otherwise hit 2nd level TLB
*/
if (dse.st_stlb_miss)
val |= P(TLB, MISS);
else
val |= P(TLB, HIT);
/*
* bit 0: hit L1 data cache
* if not set, then all we know is that
* it missed L1D
*/
if (dse.st_l1d_hit)
val |= P(LVL, HIT);
else
val |= P(LVL, MISS);
/*
* bit 5: Locked prefix
*/
if (dse.st_locked)
val |= P(LOCK, LOCKED);
return val;
}
static u64 precise_datala_hsw(struct perf_event *event, u64 status)
{
union perf_mem_data_src dse;
dse.val = PERF_MEM_NA;
if (event->hw.flags & PERF_X86_EVENT_PEBS_ST_HSW)
dse.mem_op = PERF_MEM_OP_STORE;
else if (event->hw.flags & PERF_X86_EVENT_PEBS_LD_HSW)
dse.mem_op = PERF_MEM_OP_LOAD;
/*
* L1 info only valid for following events:
*
* MEM_UOPS_RETIRED.STLB_MISS_STORES
* MEM_UOPS_RETIRED.LOCK_STORES
* MEM_UOPS_RETIRED.SPLIT_STORES
* MEM_UOPS_RETIRED.ALL_STORES
*/
if (event->hw.flags & PERF_X86_EVENT_PEBS_ST_HSW) {
if (status & 1)
dse.mem_lvl = PERF_MEM_LVL_L1 | PERF_MEM_LVL_HIT;
else
dse.mem_lvl = PERF_MEM_LVL_L1 | PERF_MEM_LVL_MISS;
}
return dse.val;
}
static u64 load_latency_data(u64 status)
{
union intel_x86_pebs_dse dse;
u64 val;
dse.val = status;
/*
* use the mapping table for bit 0-3
*/
val = pebs_data_source[dse.ld_dse];
/*
* Nehalem models do not support TLB, Lock infos
*/
if (x86_pmu.pebs_no_tlb) {
val |= P(TLB, NA) | P(LOCK, NA);
return val;
}
/*
* bit 4: TLB access
* 0 = did not miss 2nd level TLB
* 1 = missed 2nd level TLB
*/
if (dse.ld_stlb_miss)
val |= P(TLB, MISS) | P(TLB, L2);
else
val |= P(TLB, HIT) | P(TLB, L1) | P(TLB, L2);
/*
* bit 5: locked prefix
*/
if (dse.ld_locked)
val |= P(LOCK, LOCKED);
return val;
}
struct pebs_record_core {
u64 flags, ip;
u64 ax, bx, cx, dx;
u64 si, di, bp, sp;
u64 r8, r9, r10, r11;
u64 r12, r13, r14, r15;
};
struct pebs_record_nhm {
u64 flags, ip;
u64 ax, bx, cx, dx;
u64 si, di, bp, sp;
u64 r8, r9, r10, r11;
u64 r12, r13, r14, r15;
u64 status, dla, dse, lat;
};
/*
* Same as pebs_record_nhm, with two additional fields.
*/
struct pebs_record_hsw {
u64 flags, ip;
u64 ax, bx, cx, dx;
u64 si, di, bp, sp;
u64 r8, r9, r10, r11;
u64 r12, r13, r14, r15;
u64 status, dla, dse, lat;
u64 real_ip, tsx_tuning;
};
union hsw_tsx_tuning {
struct {
u32 cycles_last_block : 32,
hle_abort : 1,
rtm_abort : 1,
instruction_abort : 1,
non_instruction_abort : 1,
retry : 1,
data_conflict : 1,
capacity_writes : 1,
capacity_reads : 1;
};
u64 value;
};
#define PEBS_HSW_TSX_FLAGS 0xff00000000ULL
/* Same as HSW, plus TSC */
struct pebs_record_skl {
u64 flags, ip;
u64 ax, bx, cx, dx;
u64 si, di, bp, sp;
u64 r8, r9, r10, r11;
u64 r12, r13, r14, r15;
u64 status, dla, dse, lat;
u64 real_ip, tsx_tuning;
u64 tsc;
};
void init_debug_store_on_cpu(int cpu)
{
struct debug_store *ds = per_cpu(cpu_hw_events, cpu).ds;
if (!ds)
return;
wrmsr_on_cpu(cpu, MSR_IA32_DS_AREA,
(u32)((u64)(unsigned long)ds),
(u32)((u64)(unsigned long)ds >> 32));
}
void fini_debug_store_on_cpu(int cpu)
{
if (!per_cpu(cpu_hw_events, cpu).ds)
return;
wrmsr_on_cpu(cpu, MSR_IA32_DS_AREA, 0, 0);
}
static DEFINE_PER_CPU(void *, insn_buffer);
static void ds_update_cea(void *cea, void *addr, size_t size, pgprot_t prot)
{
unsigned long start = (unsigned long)cea;
phys_addr_t pa;
size_t msz = 0;
pa = virt_to_phys(addr);
preempt_disable();
for (; msz < size; msz += PAGE_SIZE, pa += PAGE_SIZE, cea += PAGE_SIZE)
cea_set_pte(cea, pa, prot);
/*
* This is a cross-CPU update of the cpu_entry_area, we must shoot down
* all TLB entries for it.
*/
flush_tlb_kernel_range(start, start + size);
preempt_enable();
}
static void ds_clear_cea(void *cea, size_t size)
{
unsigned long start = (unsigned long)cea;
size_t msz = 0;
preempt_disable();
for (; msz < size; msz += PAGE_SIZE, cea += PAGE_SIZE)
cea_set_pte(cea, 0, PAGE_NONE);
flush_tlb_kernel_range(start, start + size);
preempt_enable();
}
static void *dsalloc_pages(size_t size, gfp_t flags, int cpu)
{
unsigned int order = get_order(size);
int node = cpu_to_node(cpu);
struct page *page;
page = __alloc_pages_node(node, flags | __GFP_ZERO, order);
return page ? page_address(page) : NULL;
}
static void dsfree_pages(const void *buffer, size_t size)
{
if (buffer)
free_pages((unsigned long)buffer, get_order(size));
}
static int alloc_pebs_buffer(int cpu)
{
struct cpu_hw_events *hwev = per_cpu_ptr(&cpu_hw_events, cpu);
struct debug_store *ds = hwev->ds;
size_t bsiz = x86_pmu.pebs_buffer_size;
int max, node = cpu_to_node(cpu);
void *buffer, *ibuffer, *cea;
if (!x86_pmu.pebs)
return 0;
buffer = dsalloc_pages(bsiz, GFP_KERNEL, cpu);
if (unlikely(!buffer))
return -ENOMEM;
/*
* HSW+ already provides us the eventing ip; no need to allocate this
* buffer then.
*/
if (x86_pmu.intel_cap.pebs_format < 2) {
ibuffer = kzalloc_node(PEBS_FIXUP_SIZE, GFP_KERNEL, node);
if (!ibuffer) {
dsfree_pages(buffer, bsiz);
return -ENOMEM;
}
per_cpu(insn_buffer, cpu) = ibuffer;
}
hwev->ds_pebs_vaddr = buffer;
/* Update the cpu entry area mapping */
cea = &get_cpu_entry_area(cpu)->cpu_debug_buffers.pebs_buffer;
ds->pebs_buffer_base = (unsigned long) cea;
ds_update_cea(cea, buffer, bsiz, PAGE_KERNEL);
ds->pebs_index = ds->pebs_buffer_base;
max = x86_pmu.pebs_record_size * (bsiz / x86_pmu.pebs_record_size);
ds->pebs_absolute_maximum = ds->pebs_buffer_base + max;
return 0;
}
static void release_pebs_buffer(int cpu)
{
struct cpu_hw_events *hwev = per_cpu_ptr(&cpu_hw_events, cpu);
void *cea;
if (!x86_pmu.pebs)
return;
kfree(per_cpu(insn_buffer, cpu));
per_cpu(insn_buffer, cpu) = NULL;
/* Clear the fixmap */
cea = &get_cpu_entry_area(cpu)->cpu_debug_buffers.pebs_buffer;
ds_clear_cea(cea, x86_pmu.pebs_buffer_size);
dsfree_pages(hwev->ds_pebs_vaddr, x86_pmu.pebs_buffer_size);
hwev->ds_pebs_vaddr = NULL;
}
static int alloc_bts_buffer(int cpu)
{
struct cpu_hw_events *hwev = per_cpu_ptr(&cpu_hw_events, cpu);
struct debug_store *ds = hwev->ds;
void *buffer, *cea;
int max;
if (!x86_pmu.bts)
return 0;
buffer = dsalloc_pages(BTS_BUFFER_SIZE, GFP_KERNEL | __GFP_NOWARN, cpu);
if (unlikely(!buffer)) {
WARN_ONCE(1, "%s: BTS buffer allocation failure\n", __func__);
return -ENOMEM;
}
hwev->ds_bts_vaddr = buffer;
/* Update the fixmap */
cea = &get_cpu_entry_area(cpu)->cpu_debug_buffers.bts_buffer;
ds->bts_buffer_base = (unsigned long) cea;
ds_update_cea(cea, buffer, BTS_BUFFER_SIZE, PAGE_KERNEL);
ds->bts_index = ds->bts_buffer_base;
max = BTS_BUFFER_SIZE / BTS_RECORD_SIZE;
ds->bts_absolute_maximum = ds->bts_buffer_base +
max * BTS_RECORD_SIZE;
ds->bts_interrupt_threshold = ds->bts_absolute_maximum -
(max / 16) * BTS_RECORD_SIZE;
return 0;
}
static void release_bts_buffer(int cpu)
{
struct cpu_hw_events *hwev = per_cpu_ptr(&cpu_hw_events, cpu);
void *cea;
if (!x86_pmu.bts)
return;
/* Clear the fixmap */
cea = &get_cpu_entry_area(cpu)->cpu_debug_buffers.bts_buffer;
ds_clear_cea(cea, BTS_BUFFER_SIZE);
dsfree_pages(hwev->ds_bts_vaddr, BTS_BUFFER_SIZE);
hwev->ds_bts_vaddr = NULL;
}
static int alloc_ds_buffer(int cpu)
{
struct debug_store *ds = &get_cpu_entry_area(cpu)->cpu_debug_store;
memset(ds, 0, sizeof(*ds));
per_cpu(cpu_hw_events, cpu).ds = ds;
return 0;
}
static void release_ds_buffer(int cpu)
{
per_cpu(cpu_hw_events, cpu).ds = NULL;
}
void release_ds_buffers(void)
{
int cpu;
if (!x86_pmu.bts && !x86_pmu.pebs)
return;
for_each_possible_cpu(cpu)
release_ds_buffer(cpu);
for_each_possible_cpu(cpu) {
/*
* Again, ignore errors from offline CPUs, they will no longer
* observe cpu_hw_events.ds and not program the DS_AREA when
* they come up.
*/
fini_debug_store_on_cpu(cpu);
}
for_each_possible_cpu(cpu) {
release_pebs_buffer(cpu);
release_bts_buffer(cpu);
}
}
void reserve_ds_buffers(void)
{
int bts_err = 0, pebs_err = 0;
int cpu;
x86_pmu.bts_active = 0;
x86_pmu.pebs_active = 0;
if (!x86_pmu.bts && !x86_pmu.pebs)
return;
if (!x86_pmu.bts)
bts_err = 1;
if (!x86_pmu.pebs)
pebs_err = 1;
for_each_possible_cpu(cpu) {
if (alloc_ds_buffer(cpu)) {
bts_err = 1;
pebs_err = 1;
}
if (!bts_err && alloc_bts_buffer(cpu))
bts_err = 1;
if (!pebs_err && alloc_pebs_buffer(cpu))
pebs_err = 1;
if (bts_err && pebs_err)
break;
}
if (bts_err) {
for_each_possible_cpu(cpu)
release_bts_buffer(cpu);
}
if (pebs_err) {
for_each_possible_cpu(cpu)
release_pebs_buffer(cpu);
}
if (bts_err && pebs_err) {
for_each_possible_cpu(cpu)
release_ds_buffer(cpu);
} else {
if (x86_pmu.bts && !bts_err)
x86_pmu.bts_active = 1;
if (x86_pmu.pebs && !pebs_err)
x86_pmu.pebs_active = 1;
for_each_possible_cpu(cpu) {
/*
* Ignores wrmsr_on_cpu() errors for offline CPUs they
* will get this call through intel_pmu_cpu_starting().
*/
init_debug_store_on_cpu(cpu);
}
}
}
/*
* BTS
*/
struct event_constraint bts_constraint =
EVENT_CONSTRAINT(0, 1ULL << INTEL_PMC_IDX_FIXED_BTS, 0);
void intel_pmu_enable_bts(u64 config)
{
unsigned long debugctlmsr;
debugctlmsr = get_debugctlmsr();
debugctlmsr |= DEBUGCTLMSR_TR;
debugctlmsr |= DEBUGCTLMSR_BTS;
if (config & ARCH_PERFMON_EVENTSEL_INT)
debugctlmsr |= DEBUGCTLMSR_BTINT;
if (!(config & ARCH_PERFMON_EVENTSEL_OS))
debugctlmsr |= DEBUGCTLMSR_BTS_OFF_OS;
if (!(config & ARCH_PERFMON_EVENTSEL_USR))
debugctlmsr |= DEBUGCTLMSR_BTS_OFF_USR;
update_debugctlmsr(debugctlmsr);
}
void intel_pmu_disable_bts(void)
{
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
unsigned long debugctlmsr;
if (!cpuc->ds)
return;
debugctlmsr = get_debugctlmsr();
debugctlmsr &=
~(DEBUGCTLMSR_TR | DEBUGCTLMSR_BTS | DEBUGCTLMSR_BTINT |
DEBUGCTLMSR_BTS_OFF_OS | DEBUGCTLMSR_BTS_OFF_USR);
update_debugctlmsr(debugctlmsr);
}
int intel_pmu_drain_bts_buffer(void)
{
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
struct debug_store *ds = cpuc->ds;
struct bts_record {
u64 from;
u64 to;
u64 flags;
};
struct perf_event *event = cpuc->events[INTEL_PMC_IDX_FIXED_BTS];
struct bts_record *at, *base, *top;
struct perf_output_handle handle;
struct perf_event_header header;
struct perf_sample_data data;
unsigned long skip = 0;
struct pt_regs regs;
if (!event)
return 0;
if (!x86_pmu.bts_active)
return 0;
base = (struct bts_record *)(unsigned long)ds->bts_buffer_base;
top = (struct bts_record *)(unsigned long)ds->bts_index;
if (top <= base)
return 0;
memset(®s, 0, sizeof(regs));
ds->bts_index = ds->bts_buffer_base;
perf_sample_data_init(&data, 0, event->hw.last_period);
/*
* BTS leaks kernel addresses in branches across the cpl boundary,
* such as traps or system calls, so unless the user is asking for
* kernel tracing (and right now it's not possible), we'd need to
* filter them out. But first we need to count how many of those we
* have in the current batch. This is an extra O(n) pass, however,
* it's much faster than the other one especially considering that
* n <= 2560 (BTS_BUFFER_SIZE / BTS_RECORD_SIZE * 15/16; see the
* alloc_bts_buffer()).
*/
for (at = base; at < top; at++) {
/*
* Note that right now *this* BTS code only works if
* attr::exclude_kernel is set, but let's keep this extra
* check here in case that changes.
*/
if (event->attr.exclude_kernel &&
(kernel_ip(at->from) || kernel_ip(at->to)))
skip++;
}
/*
* Prepare a generic sample, i.e. fill in the invariant fields.
* We will overwrite the from and to address before we output
* the sample.
*/
rcu_read_lock();
perf_prepare_sample(&header, &data, event, ®s);
if (perf_output_begin(&handle, event, header.size *
(top - base - skip)))
goto unlock;
for (at = base; at < top; at++) {
/* Filter out any records that contain kernel addresses. */
if (event->attr.exclude_kernel &&
(kernel_ip(at->from) || kernel_ip(at->to)))
continue;
data.ip = at->from;
data.addr = at->to;
perf_output_sample(&handle, &header, &data, event);
}
perf_output_end(&handle);
/* There's new data available. */
event->hw.interrupts++;
event->pending_kill = POLL_IN;
unlock:
rcu_read_unlock();
return 1;
}
static inline void intel_pmu_drain_pebs_buffer(void)
{
struct pt_regs regs;
x86_pmu.drain_pebs(®s);
}
/*
* PEBS
*/
struct event_constraint intel_core2_pebs_event_constraints[] = {
INTEL_FLAGS_UEVENT_CONSTRAINT(0x00c0, 0x1), /* INST_RETIRED.ANY */
INTEL_FLAGS_UEVENT_CONSTRAINT(0xfec1, 0x1), /* X87_OPS_RETIRED.ANY */
INTEL_FLAGS_UEVENT_CONSTRAINT(0x00c5, 0x1), /* BR_INST_RETIRED.MISPRED */
INTEL_FLAGS_UEVENT_CONSTRAINT(0x1fc7, 0x1), /* SIMD_INST_RETURED.ANY */
INTEL_FLAGS_EVENT_CONSTRAINT(0xcb, 0x1), /* MEM_LOAD_RETIRED.* */
/* INST_RETIRED.ANY_P, inv=1, cmask=16 (cycles:p). */
INTEL_FLAGS_EVENT_CONSTRAINT(0x108000c0, 0x01),
EVENT_CONSTRAINT_END
};
struct event_constraint intel_atom_pebs_event_constraints[] = {
INTEL_FLAGS_UEVENT_CONSTRAINT(0x00c0, 0x1), /* INST_RETIRED.ANY */
INTEL_FLAGS_UEVENT_CONSTRAINT(0x00c5, 0x1), /* MISPREDICTED_BRANCH_RETIRED */
INTEL_FLAGS_EVENT_CONSTRAINT(0xcb, 0x1), /* MEM_LOAD_RETIRED.* */
/* INST_RETIRED.ANY_P, inv=1, cmask=16 (cycles:p). */
INTEL_FLAGS_EVENT_CONSTRAINT(0x108000c0, 0x01),
/* Allow all events as PEBS with no flags */
INTEL_ALL_EVENT_CONSTRAINT(0, 0x1),
EVENT_CONSTRAINT_END
};
struct event_constraint intel_slm_pebs_event_constraints[] = {
/* INST_RETIRED.ANY_P, inv=1, cmask=16 (cycles:p). */
INTEL_FLAGS_EVENT_CONSTRAINT(0x108000c0, 0x1),
/* Allow all events as PEBS with no flags */
INTEL_ALL_EVENT_CONSTRAINT(0, 0x1),
EVENT_CONSTRAINT_END
};
struct event_constraint intel_glm_pebs_event_constraints[] = {
/* Allow all events as PEBS with no flags */
INTEL_ALL_EVENT_CONSTRAINT(0, 0x1),
EVENT_CONSTRAINT_END
};
struct event_constraint intel_glp_pebs_event_constraints[] = {
/* Allow all events as PEBS with no flags */
INTEL_ALL_EVENT_CONSTRAINT(0, 0xf),
EVENT_CONSTRAINT_END
};
struct event_constraint intel_nehalem_pebs_event_constraints[] = {
INTEL_PLD_CONSTRAINT(0x100b, 0xf), /* MEM_INST_RETIRED.* */
INTEL_FLAGS_EVENT_CONSTRAINT(0x0f, 0xf), /* MEM_UNCORE_RETIRED.* */
INTEL_FLAGS_UEVENT_CONSTRAINT(0x010c, 0xf), /* MEM_STORE_RETIRED.DTLB_MISS */
INTEL_FLAGS_EVENT_CONSTRAINT(0xc0, 0xf), /* INST_RETIRED.ANY */
INTEL_EVENT_CONSTRAINT(0xc2, 0xf), /* UOPS_RETIRED.* */
INTEL_FLAGS_EVENT_CONSTRAINT(0xc4, 0xf), /* BR_INST_RETIRED.* */
INTEL_FLAGS_UEVENT_CONSTRAINT(0x02c5, 0xf), /* BR_MISP_RETIRED.NEAR_CALL */
INTEL_FLAGS_EVENT_CONSTRAINT(0xc7, 0xf), /* SSEX_UOPS_RETIRED.* */
INTEL_FLAGS_UEVENT_CONSTRAINT(0x20c8, 0xf), /* ITLB_MISS_RETIRED */
INTEL_FLAGS_EVENT_CONSTRAINT(0xcb, 0xf), /* MEM_LOAD_RETIRED.* */
INTEL_FLAGS_EVENT_CONSTRAINT(0xf7, 0xf), /* FP_ASSIST.* */
/* INST_RETIRED.ANY_P, inv=1, cmask=16 (cycles:p). */
INTEL_FLAGS_EVENT_CONSTRAINT(0x108000c0, 0x0f),
EVENT_CONSTRAINT_END
};
struct event_constraint intel_westmere_pebs_event_constraints[] = {
INTEL_PLD_CONSTRAINT(0x100b, 0xf), /* MEM_INST_RETIRED.* */
INTEL_FLAGS_EVENT_CONSTRAINT(0x0f, 0xf), /* MEM_UNCORE_RETIRED.* */
INTEL_FLAGS_UEVENT_CONSTRAINT(0x010c, 0xf), /* MEM_STORE_RETIRED.DTLB_MISS */
INTEL_FLAGS_EVENT_CONSTRAINT(0xc0, 0xf), /* INSTR_RETIRED.* */
INTEL_EVENT_CONSTRAINT(0xc2, 0xf), /* UOPS_RETIRED.* */
INTEL_FLAGS_EVENT_CONSTRAINT(0xc4, 0xf), /* BR_INST_RETIRED.* */
INTEL_FLAGS_EVENT_CONSTRAINT(0xc5, 0xf), /* BR_MISP_RETIRED.* */
INTEL_FLAGS_EVENT_CONSTRAINT(0xc7, 0xf), /* SSEX_UOPS_RETIRED.* */
INTEL_FLAGS_UEVENT_CONSTRAINT(0x20c8, 0xf), /* ITLB_MISS_RETIRED */
INTEL_FLAGS_EVENT_CONSTRAINT(0xcb, 0xf), /* MEM_LOAD_RETIRED.* */
INTEL_FLAGS_EVENT_CONSTRAINT(0xf7, 0xf), /* FP_ASSIST.* */
/* INST_RETIRED.ANY_P, inv=1, cmask=16 (cycles:p). */
INTEL_FLAGS_EVENT_CONSTRAINT(0x108000c0, 0x0f),
EVENT_CONSTRAINT_END
};
struct event_constraint intel_snb_pebs_event_constraints[] = {
INTEL_FLAGS_UEVENT_CONSTRAINT(0x01c0, 0x2), /* INST_RETIRED.PRECDIST */
INTEL_PLD_CONSTRAINT(0x01cd, 0x8), /* MEM_TRANS_RETIRED.LAT_ABOVE_THR */
INTEL_PST_CONSTRAINT(0x02cd, 0x8), /* MEM_TRANS_RETIRED.PRECISE_STORES */
/* UOPS_RETIRED.ALL, inv=1, cmask=16 (cycles:p). */
INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c2, 0xf),
INTEL_EXCLEVT_CONSTRAINT(0xd0, 0xf), /* MEM_UOP_RETIRED.* */
INTEL_EXCLEVT_CONSTRAINT(0xd1, 0xf), /* MEM_LOAD_UOPS_RETIRED.* */
INTEL_EXCLEVT_CONSTRAINT(0xd2, 0xf), /* MEM_LOAD_UOPS_LLC_HIT_RETIRED.* */
INTEL_EXCLEVT_CONSTRAINT(0xd3, 0xf), /* MEM_LOAD_UOPS_LLC_MISS_RETIRED.* */
/* Allow all events as PEBS with no flags */
INTEL_ALL_EVENT_CONSTRAINT(0, 0xf),
EVENT_CONSTRAINT_END
};
struct event_constraint intel_ivb_pebs_event_constraints[] = {
INTEL_FLAGS_UEVENT_CONSTRAINT(0x01c0, 0x2), /* INST_RETIRED.PRECDIST */
INTEL_PLD_CONSTRAINT(0x01cd, 0x8), /* MEM_TRANS_RETIRED.LAT_ABOVE_THR */
INTEL_PST_CONSTRAINT(0x02cd, 0x8), /* MEM_TRANS_RETIRED.PRECISE_STORES */
/* UOPS_RETIRED.ALL, inv=1, cmask=16 (cycles:p). */
INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c2, 0xf),
/* INST_RETIRED.PREC_DIST, inv=1, cmask=16 (cycles:ppp). */
INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c0, 0x2),
INTEL_EXCLEVT_CONSTRAINT(0xd0, 0xf), /* MEM_UOP_RETIRED.* */
INTEL_EXCLEVT_CONSTRAINT(0xd1, 0xf), /* MEM_LOAD_UOPS_RETIRED.* */
INTEL_EXCLEVT_CONSTRAINT(0xd2, 0xf), /* MEM_LOAD_UOPS_LLC_HIT_RETIRED.* */
INTEL_EXCLEVT_CONSTRAINT(0xd3, 0xf), /* MEM_LOAD_UOPS_LLC_MISS_RETIRED.* */
/* Allow all events as PEBS with no flags */
INTEL_ALL_EVENT_CONSTRAINT(0, 0xf),
EVENT_CONSTRAINT_END
};
struct event_constraint intel_hsw_pebs_event_constraints[] = {
INTEL_FLAGS_UEVENT_CONSTRAINT(0x01c0, 0x2), /* INST_RETIRED.PRECDIST */
INTEL_PLD_CONSTRAINT(0x01cd, 0xf), /* MEM_TRANS_RETIRED.* */
/* UOPS_RETIRED.ALL, inv=1, cmask=16 (cycles:p). */
INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c2, 0xf),
/* INST_RETIRED.PREC_DIST, inv=1, cmask=16 (cycles:ppp). */
INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c0, 0x2),
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_NA(0x01c2, 0xf), /* UOPS_RETIRED.ALL */
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_XLD(0x11d0, 0xf), /* MEM_UOPS_RETIRED.STLB_MISS_LOADS */
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_XLD(0x21d0, 0xf), /* MEM_UOPS_RETIRED.LOCK_LOADS */
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_XLD(0x41d0, 0xf), /* MEM_UOPS_RETIRED.SPLIT_LOADS */
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_XLD(0x81d0, 0xf), /* MEM_UOPS_RETIRED.ALL_LOADS */
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_XST(0x12d0, 0xf), /* MEM_UOPS_RETIRED.STLB_MISS_STORES */
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_XST(0x42d0, 0xf), /* MEM_UOPS_RETIRED.SPLIT_STORES */
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_XST(0x82d0, 0xf), /* MEM_UOPS_RETIRED.ALL_STORES */
INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_XLD(0xd1, 0xf), /* MEM_LOAD_UOPS_RETIRED.* */
INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_XLD(0xd2, 0xf), /* MEM_LOAD_UOPS_L3_HIT_RETIRED.* */
INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_XLD(0xd3, 0xf), /* MEM_LOAD_UOPS_L3_MISS_RETIRED.* */
/* Allow all events as PEBS with no flags */
INTEL_ALL_EVENT_CONSTRAINT(0, 0xf),
EVENT_CONSTRAINT_END
};
struct event_constraint intel_bdw_pebs_event_constraints[] = {
INTEL_FLAGS_UEVENT_CONSTRAINT(0x01c0, 0x2), /* INST_RETIRED.PRECDIST */
INTEL_PLD_CONSTRAINT(0x01cd, 0xf), /* MEM_TRANS_RETIRED.* */
/* UOPS_RETIRED.ALL, inv=1, cmask=16 (cycles:p). */
INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c2, 0xf),
/* INST_RETIRED.PREC_DIST, inv=1, cmask=16 (cycles:ppp). */
INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c0, 0x2),
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_NA(0x01c2, 0xf), /* UOPS_RETIRED.ALL */
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x11d0, 0xf), /* MEM_UOPS_RETIRED.STLB_MISS_LOADS */
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x21d0, 0xf), /* MEM_UOPS_RETIRED.LOCK_LOADS */
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x41d0, 0xf), /* MEM_UOPS_RETIRED.SPLIT_LOADS */
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x81d0, 0xf), /* MEM_UOPS_RETIRED.ALL_LOADS */
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_ST(0x12d0, 0xf), /* MEM_UOPS_RETIRED.STLB_MISS_STORES */
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_ST(0x42d0, 0xf), /* MEM_UOPS_RETIRED.SPLIT_STORES */
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_ST(0x82d0, 0xf), /* MEM_UOPS_RETIRED.ALL_STORES */
INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_LD(0xd1, 0xf), /* MEM_LOAD_UOPS_RETIRED.* */
INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_LD(0xd2, 0xf), /* MEM_LOAD_UOPS_L3_HIT_RETIRED.* */
INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_LD(0xd3, 0xf), /* MEM_LOAD_UOPS_L3_MISS_RETIRED.* */
/* Allow all events as PEBS with no flags */
INTEL_ALL_EVENT_CONSTRAINT(0, 0xf),
EVENT_CONSTRAINT_END
};
struct event_constraint intel_skl_pebs_event_constraints[] = {
INTEL_FLAGS_UEVENT_CONSTRAINT(0x1c0, 0x2), /* INST_RETIRED.PREC_DIST */
/* INST_RETIRED.PREC_DIST, inv=1, cmask=16 (cycles:ppp). */
INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c0, 0x2),
/* INST_RETIRED.TOTAL_CYCLES_PS (inv=1, cmask=16) (cycles:p). */
INTEL_FLAGS_EVENT_CONSTRAINT(0x108000c0, 0x0f),
INTEL_PLD_CONSTRAINT(0x1cd, 0xf), /* MEM_TRANS_RETIRED.* */
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x11d0, 0xf), /* MEM_INST_RETIRED.STLB_MISS_LOADS */
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_ST(0x12d0, 0xf), /* MEM_INST_RETIRED.STLB_MISS_STORES */
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x21d0, 0xf), /* MEM_INST_RETIRED.LOCK_LOADS */
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_ST(0x22d0, 0xf), /* MEM_INST_RETIRED.LOCK_STORES */
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x41d0, 0xf), /* MEM_INST_RETIRED.SPLIT_LOADS */
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_ST(0x42d0, 0xf), /* MEM_INST_RETIRED.SPLIT_STORES */
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x81d0, 0xf), /* MEM_INST_RETIRED.ALL_LOADS */
INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_ST(0x82d0, 0xf), /* MEM_INST_RETIRED.ALL_STORES */
INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_LD(0xd1, 0xf), /* MEM_LOAD_RETIRED.* */
INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_LD(0xd2, 0xf), /* MEM_LOAD_L3_HIT_RETIRED.* */
INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_LD(0xd3, 0xf), /* MEM_LOAD_L3_MISS_RETIRED.* */
/* Allow all events as PEBS with no flags */
INTEL_ALL_EVENT_CONSTRAINT(0, 0xf),
EVENT_CONSTRAINT_END
};
struct event_constraint *intel_pebs_constraints(struct perf_event *event)
{
struct event_constraint *c;
if (!event->attr.precise_ip)
return NULL;
if (x86_pmu.pebs_constraints) {
for_each_event_constraint(c, x86_pmu.pebs_constraints) {
if ((event->hw.config & c->cmask) == c->code) {
event->hw.flags |= c->flags;
return c;
}
}
}
return &emptyconstraint;
}
/*
* We need the sched_task callback even for per-cpu events when we use
* the large interrupt threshold, such that we can provide PID and TID
* to PEBS samples.
*/
static inline bool pebs_needs_sched_cb(struct cpu_hw_events *cpuc)
{
return cpuc->n_pebs && (cpuc->n_pebs == cpuc->n_large_pebs);
}
void intel_pmu_pebs_sched_task(struct perf_event_context *ctx, bool sched_in)
{
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
if (!sched_in && pebs_needs_sched_cb(cpuc))
intel_pmu_drain_pebs_buffer();
}
static inline void pebs_update_threshold(struct cpu_hw_events *cpuc)
{
struct debug_store *ds = cpuc->ds;
u64 threshold;
if (cpuc->n_pebs == cpuc->n_large_pebs) {
threshold = ds->pebs_absolute_maximum -
x86_pmu.max_pebs_events * x86_pmu.pebs_record_size;
} else {
threshold = ds->pebs_buffer_base + x86_pmu.pebs_record_size;
}
ds->pebs_interrupt_threshold = threshold;
}
static void
pebs_update_state(bool needed_cb, struct cpu_hw_events *cpuc, struct pmu *pmu)
{
/*
* Make sure we get updated with the first PEBS
* event. It will trigger also during removal, but
* that does not hurt:
*/
bool update = cpuc->n_pebs == 1;
if (needed_cb != pebs_needs_sched_cb(cpuc)) {
if (!needed_cb)
perf_sched_cb_inc(pmu);
else
perf_sched_cb_dec(pmu);
update = true;
}
if (update)
pebs_update_threshold(cpuc);
}
void intel_pmu_pebs_add(struct perf_event *event)
{
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
struct hw_perf_event *hwc = &event->hw;
bool needed_cb = pebs_needs_sched_cb(cpuc);
cpuc->n_pebs++;
if (hwc->flags & PERF_X86_EVENT_LARGE_PEBS)
cpuc->n_large_pebs++;
pebs_update_state(needed_cb, cpuc, event->ctx->pmu);
}
void intel_pmu_pebs_enable(struct perf_event *event)
{
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
struct hw_perf_event *hwc = &event->hw;
struct debug_store *ds = cpuc->ds;
hwc->config &= ~ARCH_PERFMON_EVENTSEL_INT;
cpuc->pebs_enabled |= 1ULL << hwc->idx;
if (event->hw.flags & PERF_X86_EVENT_PEBS_LDLAT)
cpuc->pebs_enabled |= 1ULL << (hwc->idx + 32);
else if (event->hw.flags & PERF_X86_EVENT_PEBS_ST)
cpuc->pebs_enabled |= 1ULL << 63;
/*
* Use auto-reload if possible to save a MSR write in the PMI.
* This must be done in pmu::start(), because PERF_EVENT_IOC_PERIOD.
*/
if (hwc->flags & PERF_X86_EVENT_AUTO_RELOAD) {
ds->pebs_event_reset[hwc->idx] =
(u64)(-hwc->sample_period) & x86_pmu.cntval_mask;
} else {
ds->pebs_event_reset[hwc->idx] = 0;
}
}
void intel_pmu_pebs_del(struct perf_event *event)
{
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
struct hw_perf_event *hwc = &event->hw;
bool needed_cb = pebs_needs_sched_cb(cpuc);
cpuc->n_pebs--;
if (hwc->flags & PERF_X86_EVENT_LARGE_PEBS)
cpuc->n_large_pebs--;
pebs_update_state(needed_cb, cpuc, event->ctx->pmu);
}
void intel_pmu_pebs_disable(struct perf_event *event)
{
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
struct hw_perf_event *hwc = &event->hw;
if (cpuc->n_pebs == cpuc->n_large_pebs)
intel_pmu_drain_pebs_buffer();
cpuc->pebs_enabled &= ~(1ULL << hwc->idx);
if (event->hw.flags & PERF_X86_EVENT_PEBS_LDLAT)
cpuc->pebs_enabled &= ~(1ULL << (hwc->idx + 32));
else if (event->hw.flags & PERF_X86_EVENT_PEBS_ST)
cpuc->pebs_enabled &= ~(1ULL << 63);
if (cpuc->enabled)
wrmsrl(MSR_IA32_PEBS_ENABLE, cpuc->pebs_enabled);
hwc->config |= ARCH_PERFMON_EVENTSEL_INT;
}
void intel_pmu_pebs_enable_all(void)
{
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
if (cpuc->pebs_enabled)
wrmsrl(MSR_IA32_PEBS_ENABLE, cpuc->pebs_enabled);
}
void intel_pmu_pebs_disable_all(void)
{
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
if (cpuc->pebs_enabled)
wrmsrl(MSR_IA32_PEBS_ENABLE, 0);
}
static int intel_pmu_pebs_fixup_ip(struct pt_regs *regs)
{
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
unsigned long from = cpuc->lbr_entries[0].from;
unsigned long old_to, to = cpuc->lbr_entries[0].to;
unsigned long ip = regs->ip;
int is_64bit = 0;
void *kaddr;
int size;
/*
* We don't need to fixup if the PEBS assist is fault like
*/
if (!x86_pmu.intel_cap.pebs_trap)
return 1;
/*
* No LBR entry, no basic block, no rewinding
*/
if (!cpuc->lbr_stack.nr || !from || !to)
return 0;
/*
* Basic blocks should never cross user/kernel boundaries
*/
if (kernel_ip(ip) != kernel_ip(to))
return 0;
/*
* unsigned math, either ip is before the start (impossible) or
* the basic block is larger than 1 page (sanity)
*/
if ((ip - to) > PEBS_FIXUP_SIZE)
return 0;
/*
* We sampled a branch insn, rewind using the LBR stack
*/
if (ip == to) {
set_linear_ip(regs, from);
return 1;
}
size = ip - to;
if (!kernel_ip(ip)) {
int bytes;
u8 *buf = this_cpu_read(insn_buffer);
/* 'size' must fit our buffer, see above */
bytes = copy_from_user_nmi(buf, (void __user *)to, size);
if (bytes != 0)
return 0;
kaddr = buf;
} else {
kaddr = (void *)to;
}
do {
struct insn insn;
old_to = to;
#ifdef CONFIG_X86_64
is_64bit = kernel_ip(to) || !test_thread_flag(TIF_IA32);
#endif
insn_init(&insn, kaddr, size, is_64bit);
insn_get_length(&insn);
/*
* Make sure there was not a problem decoding the
* instruction and getting the length. This is
* doubly important because we have an infinite
* loop if insn.length=0.
*/
if (!insn.length)
break;
to += insn.length;
kaddr += insn.length;
size -= insn.length;
} while (to < ip);
if (to == ip) {
set_linear_ip(regs, old_to);
return 1;
}
/*
* Even though we decoded the basic block, the instruction stream
* never matched the given IP, either the TO or the IP got corrupted.
*/
return 0;
}
static inline u64 intel_hsw_weight(struct pebs_record_skl *pebs)
{
if (pebs->tsx_tuning) {
union hsw_tsx_tuning tsx = { .value = pebs->tsx_tuning };
return tsx.cycles_last_block;
}
return 0;
}
static inline u64 intel_hsw_transaction(struct pebs_record_skl *pebs)
{
u64 txn = (pebs->tsx_tuning & PEBS_HSW_TSX_FLAGS) >> 32;
/* For RTM XABORTs also log the abort code from AX */
if ((txn & PERF_TXN_TRANSACTION) && (pebs->ax & 1))
txn |= ((pebs->ax >> 24) & 0xff) << PERF_TXN_ABORT_SHIFT;
return txn;
}
static void setup_pebs_sample_data(struct perf_event *event,
struct pt_regs *iregs, void *__pebs,
struct perf_sample_data *data,
struct pt_regs *regs)
{
#define PERF_X86_EVENT_PEBS_HSW_PREC \
(PERF_X86_EVENT_PEBS_ST_HSW | \
PERF_X86_EVENT_PEBS_LD_HSW | \
PERF_X86_EVENT_PEBS_NA_HSW)
/*
* We cast to the biggest pebs_record but are careful not to
* unconditionally access the 'extra' entries.
*/
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
struct pebs_record_skl *pebs = __pebs;
u64 sample_type;
int fll, fst, dsrc;
int fl = event->hw.flags;
if (pebs == NULL)
return;
sample_type = event->attr.sample_type;
dsrc = sample_type & PERF_SAMPLE_DATA_SRC;
fll = fl & PERF_X86_EVENT_PEBS_LDLAT;
fst = fl & (PERF_X86_EVENT_PEBS_ST | PERF_X86_EVENT_PEBS_HSW_PREC);
perf_sample_data_init(data, 0, event->hw.last_period);
data->period = event->hw.last_period;
/*
* Use latency for weight (only avail with PEBS-LL)
*/
if (fll && (sample_type & PERF_SAMPLE_WEIGHT))
data->weight = pebs->lat;
/*
* data.data_src encodes the data source
*/
if (dsrc) {
u64 val = PERF_MEM_NA;
if (fll)
val = load_latency_data(pebs->dse);
else if (fst && (fl & PERF_X86_EVENT_PEBS_HSW_PREC))
val = precise_datala_hsw(event, pebs->dse);
else if (fst)
val = precise_store_data(pebs->dse);
data->data_src.val = val;
}
/*
* We must however always use iregs for the unwinder to stay sane; the
* record BP,SP,IP can point into thin air when the record is from a
* previous PMI context or an (I)RET happend between the record and
* PMI.
*/
if (sample_type & PERF_SAMPLE_CALLCHAIN)
data->callchain = perf_callchain(event, iregs);
/*
* We use the interrupt regs as a base because the PEBS record does not
* contain a full regs set, specifically it seems to lack segment
* descriptors, which get used by things like user_mode().
*
* In the simple case fix up only the IP for PERF_SAMPLE_IP.
*/
*regs = *iregs;
/*
* Initialize regs_>flags from PEBS,
* Clear exact bit (which uses x86 EFLAGS Reserved bit 3),
* i.e., do not rely on it being zero:
*/
regs->flags = pebs->flags & ~PERF_EFLAGS_EXACT;
if (sample_type & PERF_SAMPLE_REGS_INTR) {
regs->ax = pebs->ax;
regs->bx = pebs->bx;
regs->cx = pebs->cx;
regs->dx = pebs->dx;
regs->si = pebs->si;
regs->di = pebs->di;
regs->bp = pebs->bp;
regs->sp = pebs->sp;
#ifndef CONFIG_X86_32
regs->r8 = pebs->r8;
regs->r9 = pebs->r9;
regs->r10 = pebs->r10;
regs->r11 = pebs->r11;
regs->r12 = pebs->r12;
regs->r13 = pebs->r13;
regs->r14 = pebs->r14;
regs->r15 = pebs->r15;
#endif
}
if (event->attr.precise_ip > 1) {
/*
* Haswell and later processors have an 'eventing IP'
* (real IP) which fixes the off-by-1 skid in hardware.
* Use it when precise_ip >= 2 :
*/
if (x86_pmu.intel_cap.pebs_format >= 2) {
set_linear_ip(regs, pebs->real_ip);
regs->flags |= PERF_EFLAGS_EXACT;
} else {
/* Otherwise, use PEBS off-by-1 IP: */
set_linear_ip(regs, pebs->ip);
/*
* With precise_ip >= 2, try to fix up the off-by-1 IP
* using the LBR. If successful, the fixup function
* corrects regs->ip and calls set_linear_ip() on regs:
*/
if (intel_pmu_pebs_fixup_ip(regs))
regs->flags |= PERF_EFLAGS_EXACT;
}
} else {
/*
* When precise_ip == 1, return the PEBS off-by-1 IP,
* no fixup attempted:
*/
set_linear_ip(regs, pebs->ip);
}
if ((sample_type & (PERF_SAMPLE_ADDR | PERF_SAMPLE_PHYS_ADDR)) &&
x86_pmu.intel_cap.pebs_format >= 1)
data->addr = pebs->dla;
if (x86_pmu.intel_cap.pebs_format >= 2) {
/* Only set the TSX weight when no memory weight. */
if ((sample_type & PERF_SAMPLE_WEIGHT) && !fll)
data->weight = intel_hsw_weight(pebs);
if (sample_type & PERF_SAMPLE_TRANSACTION)
data->txn = intel_hsw_transaction(pebs);
}
/*
* v3 supplies an accurate time stamp, so we use that
* for the time stamp.
*
* We can only do this for the default trace clock.
*/
if (x86_pmu.intel_cap.pebs_format >= 3 &&
event->attr.use_clockid == 0)
data->time = native_sched_clock_from_tsc(pebs->tsc);
if (has_branch_stack(event))
data->br_stack = &cpuc->lbr_stack;
}
static inline void *
get_next_pebs_record_by_bit(void *base, void *top, int bit)
{
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
void *at;
u64 pebs_status;
/*
* fmt0 does not have a status bitfield (does not use
* perf_record_nhm format)
*/
if (x86_pmu.intel_cap.pebs_format < 1)
return base;
if (base == NULL)
return NULL;
for (at = base; at < top; at += x86_pmu.pebs_record_size) {
struct pebs_record_nhm *p = at;
if (test_bit(bit, (unsigned long *)&p->status)) {
/* PEBS v3 has accurate status bits */
if (x86_pmu.intel_cap.pebs_format >= 3)
return at;
if (p->status == (1 << bit))
return at;
/* clear non-PEBS bit and re-check */
pebs_status = p->status & cpuc->pebs_enabled;
pebs_status &= PEBS_COUNTER_MASK;
if (pebs_status == (1 << bit))
return at;
}
}
return NULL;
}
void intel_pmu_auto_reload_read(struct perf_event *event)
{
WARN_ON(!(event->hw.flags & PERF_X86_EVENT_AUTO_RELOAD));
perf_pmu_disable(event->pmu);
intel_pmu_drain_pebs_buffer();
perf_pmu_enable(event->pmu);
}
/*
* Special variant of intel_pmu_save_and_restart() for auto-reload.
*/
static int
intel_pmu_save_and_restart_reload(struct perf_event *event, int count)
{
struct hw_perf_event *hwc = &event->hw;
int shift = 64 - x86_pmu.cntval_bits;
u64 period = hwc->sample_period;
u64 prev_raw_count, new_raw_count;
s64 new, old;
WARN_ON(!period);
/*
* drain_pebs() only happens when the PMU is disabled.
*/
WARN_ON(this_cpu_read(cpu_hw_events.enabled));
prev_raw_count = local64_read(&hwc->prev_count);
rdpmcl(hwc->event_base_rdpmc, new_raw_count);
local64_set(&hwc->prev_count, new_raw_count);
/*
* Since the counter increments a negative counter value and
* overflows on the sign switch, giving the interval:
*
* [-period, 0]
*
* the difference between two consequtive reads is:
*
* A) value2 - value1;
* when no overflows have happened in between,
*
* B) (0 - value1) + (value2 - (-period));
* when one overflow happened in between,
*
* C) (0 - value1) + (n - 1) * (period) + (value2 - (-period));
* when @n overflows happened in between.
*
* Here A) is the obvious difference, B) is the extension to the
* discrete interval, where the first term is to the top of the
* interval and the second term is from the bottom of the next
* interval and C) the extension to multiple intervals, where the
* middle term is the whole intervals covered.
*
* An equivalent of C, by reduction, is:
*
* value2 - value1 + n * period
*/
new = ((s64)(new_raw_count << shift) >> shift);
old = ((s64)(prev_raw_count << shift) >> shift);
local64_add(new - old + count * period, &event->count);
perf_event_update_userpage(event);
return 0;
}
static void __intel_pmu_pebs_event(struct perf_event *event,
struct pt_regs *iregs,
void *base, void *top,
int bit, int count)
{
struct hw_perf_event *hwc = &event->hw;
struct perf_sample_data data;
struct pt_regs regs;
void *at = get_next_pebs_record_by_bit(base, top, bit);
if (hwc->flags & PERF_X86_EVENT_AUTO_RELOAD) {
/*
* Now, auto-reload is only enabled in fixed period mode.
* The reload value is always hwc->sample_period.
* May need to change it, if auto-reload is enabled in
* freq mode later.
*/
intel_pmu_save_and_restart_reload(event, count);
} else if (!intel_pmu_save_and_restart(event))
return;
while (count > 1) {
setup_pebs_sample_data(event, iregs, at, &data, ®s);
perf_event_output(event, &data, ®s);
at += x86_pmu.pebs_record_size;
at = get_next_pebs_record_by_bit(at, top, bit);
count--;
}
setup_pebs_sample_data(event, iregs, at, &data, ®s);
/*
* All but the last records are processed.
* The last one is left to be able to call the overflow handler.
*/
if (perf_event_overflow(event, &data, ®s)) {
x86_pmu_stop(event, 0);
return;
}
}
static void intel_pmu_drain_pebs_core(struct pt_regs *iregs)
{
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
struct debug_store *ds = cpuc->ds;
struct perf_event *event = cpuc->events[0]; /* PMC0 only */
struct pebs_record_core *at, *top;
int n;
if (!x86_pmu.pebs_active)
return;
at = (struct pebs_record_core *)(unsigned long)ds->pebs_buffer_base;
top = (struct pebs_record_core *)(unsigned long)ds->pebs_index;
/*
* Whatever else happens, drain the thing
*/
ds->pebs_index = ds->pebs_buffer_base;
if (!test_bit(0, cpuc->active_mask))
return;
WARN_ON_ONCE(!event);
if (!event->attr.precise_ip)
return;
n = top - at;
if (n <= 0) {
if (event->hw.flags & PERF_X86_EVENT_AUTO_RELOAD)
intel_pmu_save_and_restart_reload(event, 0);
return;
}
__intel_pmu_pebs_event(event, iregs, at, top, 0, n);
}
static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs)
{
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
struct debug_store *ds = cpuc->ds;
struct perf_event *event;
void *base, *at, *top;
short counts[MAX_PEBS_EVENTS] = {};
short error[MAX_PEBS_EVENTS] = {};
int bit, i;
if (!x86_pmu.pebs_active)
return;
base = (struct pebs_record_nhm *)(unsigned long)ds->pebs_buffer_base;
top = (struct pebs_record_nhm *)(unsigned long)ds->pebs_index;
ds->pebs_index = ds->pebs_buffer_base;
if (unlikely(base >= top)) {
/*
* The drain_pebs() could be called twice in a short period
* for auto-reload event in pmu::read(). There are no
* overflows have happened in between.
* It needs to call intel_pmu_save_and_restart_reload() to
* update the event->count for this case.
*/
for_each_set_bit(bit, (unsigned long *)&cpuc->pebs_enabled,
x86_pmu.max_pebs_events) {
event = cpuc->events[bit];
if (event->hw.flags & PERF_X86_EVENT_AUTO_RELOAD)
intel_pmu_save_and_restart_reload(event, 0);
}
return;
}
for (at = base; at < top; at += x86_pmu.pebs_record_size) {
struct pebs_record_nhm *p = at;
u64 pebs_status;
pebs_status = p->status & cpuc->pebs_enabled;
pebs_status &= (1ULL << x86_pmu.max_pebs_events) - 1;
/* PEBS v3 has more accurate status bits */
if (x86_pmu.intel_cap.pebs_format >= 3) {
for_each_set_bit(bit, (unsigned long *)&pebs_status,
x86_pmu.max_pebs_events)
counts[bit]++;
continue;
}
/*
* On some CPUs the PEBS status can be zero when PEBS is
* racing with clearing of GLOBAL_STATUS.
*
* Normally we would drop that record, but in the
* case when there is only a single active PEBS event
* we can assume it's for that event.
*/
if (!pebs_status && cpuc->pebs_enabled &&
!(cpuc->pebs_enabled & (cpuc->pebs_enabled-1)))
pebs_status = cpuc->pebs_enabled;
bit = find_first_bit((unsigned long *)&pebs_status,
x86_pmu.max_pebs_events);
if (bit >= x86_pmu.max_pebs_events)
continue;
/*
* The PEBS hardware does not deal well with the situation
* when events happen near to each other and multiple bits
* are set. But it should happen rarely.
*
* If these events include one PEBS and multiple non-PEBS
* events, it doesn't impact PEBS record. The record will
* be handled normally. (slow path)
*
* If these events include two or more PEBS events, the
* records for the events can be collapsed into a single
* one, and it's not possible to reconstruct all events
* that caused the PEBS record. It's called collision.
* If collision happened, the record will be dropped.
*/
if (p->status != (1ULL << bit)) {
for_each_set_bit(i, (unsigned long *)&pebs_status,
x86_pmu.max_pebs_events)
error[i]++;
continue;
}
counts[bit]++;
}
for (bit = 0; bit < x86_pmu.max_pebs_events; bit++) {
if ((counts[bit] == 0) && (error[bit] == 0))
continue;
event = cpuc->events[bit];
if (WARN_ON_ONCE(!event))
continue;
if (WARN_ON_ONCE(!event->attr.precise_ip))
continue;
/* log dropped samples number */
if (error[bit]) {
perf_log_lost_samples(event, error[bit]);
if (perf_event_account_interrupt(event))
x86_pmu_stop(event, 0);
}
if (counts[bit]) {
__intel_pmu_pebs_event(event, iregs, base,
top, bit, counts[bit]);
}
}
}
/*
* BTS, PEBS probe and setup
*/
void __init intel_ds_init(void)
{
/*
* No support for 32bit formats
*/
if (!boot_cpu_has(X86_FEATURE_DTES64))
return;
x86_pmu.bts = boot_cpu_has(X86_FEATURE_BTS);
x86_pmu.pebs = boot_cpu_has(X86_FEATURE_PEBS);
x86_pmu.pebs_buffer_size = PEBS_BUFFER_SIZE;
if (x86_pmu.pebs) {
char pebs_type = x86_pmu.intel_cap.pebs_trap ? '+' : '-';
int format = x86_pmu.intel_cap.pebs_format;
switch (format) {
case 0:
pr_cont("PEBS fmt0%c, ", pebs_type);
x86_pmu.pebs_record_size = sizeof(struct pebs_record_core);
/*
* Using >PAGE_SIZE buffers makes the WRMSR to
* PERF_GLOBAL_CTRL in intel_pmu_enable_all()
* mysteriously hang on Core2.
*
* As a workaround, we don't do this.
*/
x86_pmu.pebs_buffer_size = PAGE_SIZE;
x86_pmu.drain_pebs = intel_pmu_drain_pebs_core;
break;
case 1:
pr_cont("PEBS fmt1%c, ", pebs_type);
x86_pmu.pebs_record_size = sizeof(struct pebs_record_nhm);
x86_pmu.drain_pebs = intel_pmu_drain_pebs_nhm;
break;
case 2:
pr_cont("PEBS fmt2%c, ", pebs_type);
x86_pmu.pebs_record_size = sizeof(struct pebs_record_hsw);
x86_pmu.drain_pebs = intel_pmu_drain_pebs_nhm;
break;
case 3:
pr_cont("PEBS fmt3%c, ", pebs_type);
x86_pmu.pebs_record_size =
sizeof(struct pebs_record_skl);
x86_pmu.drain_pebs = intel_pmu_drain_pebs_nhm;
x86_pmu.large_pebs_flags |= PERF_SAMPLE_TIME;
break;
default:
pr_cont("no PEBS fmt%d%c, ", format, pebs_type);
x86_pmu.pebs = 0;
}
}
}
void perf_restore_debug_store(void)
{
struct debug_store *ds = __this_cpu_read(cpu_hw_events.ds);
if (!x86_pmu.bts && !x86_pmu.pebs)
return;
wrmsrl(MSR_IA32_DS_AREA, (unsigned long)ds);
}
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