linux_dsm_epyc7002/tools/perf/util/cs-etm.c
Leo Yan 7100b12cf4 perf cs-etm: Generate branch sample for exception packet
The exception packet appears as one element with 'elem_type' ==
OCSD_GEN_TRC_ELEM_EXCEPTION or OCSD_GEN_TRC_ELEM_EXCEPTION_RET, which is
present for exception entry and exit respectively.  The decoder sets the
packet fields 'packet->exc' and 'packet->exc_ret' to indicate the
exception packets; but exception packets don't have a dedicated sample
type and shares the same sample type CS_ETM_RANGE with normal
instruction packets.

As a result, the exception packets are taken as normal instruction
packets and this introduces confusion in mixing different packet types.
Furthermore, these instruction range packets will be processed for
branch samples only when 'packet->last_instr_taken_branch' is true,
otherwise they will be omitted, this can introduce a mess for exception
and exception returning due to not having the complete address range
info for context switching.

To process exception packets properly, this patch introduces two new
sample types: CS_ETM_EXCEPTION and CS_ETM_EXCEPTION_RET; these two types
of packets will be handled by cs_etm__exception().  The function
cs_etm__exception() forces setting the previous CS_ETM_RANGE packet flag
'prev_packet->last_instr_taken_branch' to true, this matches well with
the program flow when the exception is trapped from user space to kernel
space, no matter if the most recent flow has branch taken or not; this
is also safe for returning to user space after exception handling.

After exception packets have their own sample type, the packet fields
'packet->exc' and 'packet->exc_ret' aren't needed anymore, so remove
them.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Robert Walker <robert.walker@arm.com>
Cc: coresight ml <coresight@lists.linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1544513908-16805-9-git-send-email-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-12-18 12:24:00 -03:00

1590 lines
40 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright(C) 2015-2018 Linaro Limited.
*
* Author: Tor Jeremiassen <tor@ti.com>
* Author: Mathieu Poirier <mathieu.poirier@linaro.org>
*/
#include <linux/bitops.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/log2.h>
#include <linux/types.h>
#include <stdlib.h>
#include "auxtrace.h"
#include "color.h"
#include "cs-etm.h"
#include "cs-etm-decoder/cs-etm-decoder.h"
#include "debug.h"
#include "evlist.h"
#include "intlist.h"
#include "machine.h"
#include "map.h"
#include "perf.h"
#include "thread.h"
#include "thread_map.h"
#include "thread-stack.h"
#include "util.h"
#define MAX_TIMESTAMP (~0ULL)
struct cs_etm_auxtrace {
struct auxtrace auxtrace;
struct auxtrace_queues queues;
struct auxtrace_heap heap;
struct itrace_synth_opts synth_opts;
struct perf_session *session;
struct machine *machine;
struct thread *unknown_thread;
u8 timeless_decoding;
u8 snapshot_mode;
u8 data_queued;
u8 sample_branches;
u8 sample_instructions;
int num_cpu;
u32 auxtrace_type;
u64 branches_sample_type;
u64 branches_id;
u64 instructions_sample_type;
u64 instructions_sample_period;
u64 instructions_id;
u64 **metadata;
u64 kernel_start;
unsigned int pmu_type;
};
struct cs_etm_queue {
struct cs_etm_auxtrace *etm;
struct thread *thread;
struct cs_etm_decoder *decoder;
struct auxtrace_buffer *buffer;
const struct cs_etm_state *state;
union perf_event *event_buf;
unsigned int queue_nr;
pid_t pid, tid;
int cpu;
u64 time;
u64 timestamp;
u64 offset;
u64 period_instructions;
struct branch_stack *last_branch;
struct branch_stack *last_branch_rb;
size_t last_branch_pos;
struct cs_etm_packet *prev_packet;
struct cs_etm_packet *packet;
};
static int cs_etm__update_queues(struct cs_etm_auxtrace *etm);
static int cs_etm__process_timeless_queues(struct cs_etm_auxtrace *etm,
pid_t tid, u64 time_);
/* PTMs ETMIDR [11:8] set to b0011 */
#define ETMIDR_PTM_VERSION 0x00000300
static u32 cs_etm__get_v7_protocol_version(u32 etmidr)
{
etmidr &= ETMIDR_PTM_VERSION;
if (etmidr == ETMIDR_PTM_VERSION)
return CS_ETM_PROTO_PTM;
return CS_ETM_PROTO_ETMV3;
}
static void cs_etm__packet_dump(const char *pkt_string)
{
const char *color = PERF_COLOR_BLUE;
int len = strlen(pkt_string);
if (len && (pkt_string[len-1] == '\n'))
color_fprintf(stdout, color, " %s", pkt_string);
else
color_fprintf(stdout, color, " %s\n", pkt_string);
fflush(stdout);
}
static void cs_etm__dump_event(struct cs_etm_auxtrace *etm,
struct auxtrace_buffer *buffer)
{
int i, ret;
const char *color = PERF_COLOR_BLUE;
struct cs_etm_decoder_params d_params;
struct cs_etm_trace_params *t_params;
struct cs_etm_decoder *decoder;
size_t buffer_used = 0;
fprintf(stdout, "\n");
color_fprintf(stdout, color,
". ... CoreSight ETM Trace data: size %zu bytes\n",
buffer->size);
/* Use metadata to fill in trace parameters for trace decoder */
t_params = zalloc(sizeof(*t_params) * etm->num_cpu);
for (i = 0; i < etm->num_cpu; i++) {
if (etm->metadata[i][CS_ETM_MAGIC] == __perf_cs_etmv3_magic) {
u32 etmidr = etm->metadata[i][CS_ETM_ETMIDR];
t_params[i].protocol =
cs_etm__get_v7_protocol_version(etmidr);
t_params[i].etmv3.reg_ctrl =
etm->metadata[i][CS_ETM_ETMCR];
t_params[i].etmv3.reg_trc_id =
etm->metadata[i][CS_ETM_ETMTRACEIDR];
} else if (etm->metadata[i][CS_ETM_MAGIC] ==
__perf_cs_etmv4_magic) {
t_params[i].protocol = CS_ETM_PROTO_ETMV4i;
t_params[i].etmv4.reg_idr0 =
etm->metadata[i][CS_ETMV4_TRCIDR0];
t_params[i].etmv4.reg_idr1 =
etm->metadata[i][CS_ETMV4_TRCIDR1];
t_params[i].etmv4.reg_idr2 =
etm->metadata[i][CS_ETMV4_TRCIDR2];
t_params[i].etmv4.reg_idr8 =
etm->metadata[i][CS_ETMV4_TRCIDR8];
t_params[i].etmv4.reg_configr =
etm->metadata[i][CS_ETMV4_TRCCONFIGR];
t_params[i].etmv4.reg_traceidr =
etm->metadata[i][CS_ETMV4_TRCTRACEIDR];
}
}
/* Set decoder parameters to simply print the trace packets */
d_params.packet_printer = cs_etm__packet_dump;
d_params.operation = CS_ETM_OPERATION_PRINT;
d_params.formatted = true;
d_params.fsyncs = false;
d_params.hsyncs = false;
d_params.frame_aligned = true;
decoder = cs_etm_decoder__new(etm->num_cpu, &d_params, t_params);
zfree(&t_params);
if (!decoder)
return;
do {
size_t consumed;
ret = cs_etm_decoder__process_data_block(
decoder, buffer->offset,
&((u8 *)buffer->data)[buffer_used],
buffer->size - buffer_used, &consumed);
if (ret)
break;
buffer_used += consumed;
} while (buffer_used < buffer->size);
cs_etm_decoder__free(decoder);
}
static int cs_etm__flush_events(struct perf_session *session,
struct perf_tool *tool)
{
int ret;
struct cs_etm_auxtrace *etm = container_of(session->auxtrace,
struct cs_etm_auxtrace,
auxtrace);
if (dump_trace)
return 0;
if (!tool->ordered_events)
return -EINVAL;
if (!etm->timeless_decoding)
return -EINVAL;
ret = cs_etm__update_queues(etm);
if (ret < 0)
return ret;
return cs_etm__process_timeless_queues(etm, -1, MAX_TIMESTAMP - 1);
}
static void cs_etm__free_queue(void *priv)
{
struct cs_etm_queue *etmq = priv;
if (!etmq)
return;
thread__zput(etmq->thread);
cs_etm_decoder__free(etmq->decoder);
zfree(&etmq->event_buf);
zfree(&etmq->last_branch);
zfree(&etmq->last_branch_rb);
zfree(&etmq->prev_packet);
zfree(&etmq->packet);
free(etmq);
}
static void cs_etm__free_events(struct perf_session *session)
{
unsigned int i;
struct cs_etm_auxtrace *aux = container_of(session->auxtrace,
struct cs_etm_auxtrace,
auxtrace);
struct auxtrace_queues *queues = &aux->queues;
for (i = 0; i < queues->nr_queues; i++) {
cs_etm__free_queue(queues->queue_array[i].priv);
queues->queue_array[i].priv = NULL;
}
auxtrace_queues__free(queues);
}
static void cs_etm__free(struct perf_session *session)
{
int i;
struct int_node *inode, *tmp;
struct cs_etm_auxtrace *aux = container_of(session->auxtrace,
struct cs_etm_auxtrace,
auxtrace);
cs_etm__free_events(session);
session->auxtrace = NULL;
/* First remove all traceID/CPU# nodes for the RB tree */
intlist__for_each_entry_safe(inode, tmp, traceid_list)
intlist__remove(traceid_list, inode);
/* Then the RB tree itself */
intlist__delete(traceid_list);
for (i = 0; i < aux->num_cpu; i++)
zfree(&aux->metadata[i]);
thread__zput(aux->unknown_thread);
zfree(&aux->metadata);
zfree(&aux);
}
static u8 cs_etm__cpu_mode(struct cs_etm_queue *etmq, u64 address)
{
struct machine *machine;
machine = etmq->etm->machine;
if (address >= etmq->etm->kernel_start) {
if (machine__is_host(machine))
return PERF_RECORD_MISC_KERNEL;
else
return PERF_RECORD_MISC_GUEST_KERNEL;
} else {
if (machine__is_host(machine))
return PERF_RECORD_MISC_USER;
else if (perf_guest)
return PERF_RECORD_MISC_GUEST_USER;
else
return PERF_RECORD_MISC_HYPERVISOR;
}
}
static u32 cs_etm__mem_access(struct cs_etm_queue *etmq, u64 address,
size_t size, u8 *buffer)
{
u8 cpumode;
u64 offset;
int len;
struct thread *thread;
struct machine *machine;
struct addr_location al;
if (!etmq)
return -1;
machine = etmq->etm->machine;
cpumode = cs_etm__cpu_mode(etmq, address);
thread = etmq->thread;
if (!thread) {
if (cpumode != PERF_RECORD_MISC_KERNEL)
return -EINVAL;
thread = etmq->etm->unknown_thread;
}
if (!thread__find_map(thread, cpumode, address, &al) || !al.map->dso)
return 0;
if (al.map->dso->data.status == DSO_DATA_STATUS_ERROR &&
dso__data_status_seen(al.map->dso, DSO_DATA_STATUS_SEEN_ITRACE))
return 0;
offset = al.map->map_ip(al.map, address);
map__load(al.map);
len = dso__data_read_offset(al.map->dso, machine, offset, buffer, size);
if (len <= 0)
return 0;
return len;
}
static struct cs_etm_queue *cs_etm__alloc_queue(struct cs_etm_auxtrace *etm,
unsigned int queue_nr)
{
int i;
struct cs_etm_decoder_params d_params;
struct cs_etm_trace_params *t_params;
struct cs_etm_queue *etmq;
size_t szp = sizeof(struct cs_etm_packet);
etmq = zalloc(sizeof(*etmq));
if (!etmq)
return NULL;
etmq->packet = zalloc(szp);
if (!etmq->packet)
goto out_free;
if (etm->synth_opts.last_branch || etm->sample_branches) {
etmq->prev_packet = zalloc(szp);
if (!etmq->prev_packet)
goto out_free;
}
if (etm->synth_opts.last_branch) {
size_t sz = sizeof(struct branch_stack);
sz += etm->synth_opts.last_branch_sz *
sizeof(struct branch_entry);
etmq->last_branch = zalloc(sz);
if (!etmq->last_branch)
goto out_free;
etmq->last_branch_rb = zalloc(sz);
if (!etmq->last_branch_rb)
goto out_free;
}
etmq->event_buf = malloc(PERF_SAMPLE_MAX_SIZE);
if (!etmq->event_buf)
goto out_free;
etmq->etm = etm;
etmq->queue_nr = queue_nr;
etmq->pid = -1;
etmq->tid = -1;
etmq->cpu = -1;
/* Use metadata to fill in trace parameters for trace decoder */
t_params = zalloc(sizeof(*t_params) * etm->num_cpu);
if (!t_params)
goto out_free;
for (i = 0; i < etm->num_cpu; i++) {
if (etm->metadata[i][CS_ETM_MAGIC] == __perf_cs_etmv3_magic) {
u32 etmidr = etm->metadata[i][CS_ETM_ETMIDR];
t_params[i].protocol =
cs_etm__get_v7_protocol_version(etmidr);
t_params[i].etmv3.reg_ctrl =
etm->metadata[i][CS_ETM_ETMCR];
t_params[i].etmv3.reg_trc_id =
etm->metadata[i][CS_ETM_ETMTRACEIDR];
} else if (etm->metadata[i][CS_ETM_MAGIC] ==
__perf_cs_etmv4_magic) {
t_params[i].protocol = CS_ETM_PROTO_ETMV4i;
t_params[i].etmv4.reg_idr0 =
etm->metadata[i][CS_ETMV4_TRCIDR0];
t_params[i].etmv4.reg_idr1 =
etm->metadata[i][CS_ETMV4_TRCIDR1];
t_params[i].etmv4.reg_idr2 =
etm->metadata[i][CS_ETMV4_TRCIDR2];
t_params[i].etmv4.reg_idr8 =
etm->metadata[i][CS_ETMV4_TRCIDR8];
t_params[i].etmv4.reg_configr =
etm->metadata[i][CS_ETMV4_TRCCONFIGR];
t_params[i].etmv4.reg_traceidr =
etm->metadata[i][CS_ETMV4_TRCTRACEIDR];
}
}
/* Set decoder parameters to simply print the trace packets */
d_params.packet_printer = cs_etm__packet_dump;
d_params.operation = CS_ETM_OPERATION_DECODE;
d_params.formatted = true;
d_params.fsyncs = false;
d_params.hsyncs = false;
d_params.frame_aligned = true;
d_params.data = etmq;
etmq->decoder = cs_etm_decoder__new(etm->num_cpu, &d_params, t_params);
zfree(&t_params);
if (!etmq->decoder)
goto out_free;
/*
* Register a function to handle all memory accesses required by
* the trace decoder library.
*/
if (cs_etm_decoder__add_mem_access_cb(etmq->decoder,
0x0L, ((u64) -1L),
cs_etm__mem_access))
goto out_free_decoder;
etmq->offset = 0;
etmq->period_instructions = 0;
return etmq;
out_free_decoder:
cs_etm_decoder__free(etmq->decoder);
out_free:
zfree(&etmq->event_buf);
zfree(&etmq->last_branch);
zfree(&etmq->last_branch_rb);
zfree(&etmq->prev_packet);
zfree(&etmq->packet);
free(etmq);
return NULL;
}
static int cs_etm__setup_queue(struct cs_etm_auxtrace *etm,
struct auxtrace_queue *queue,
unsigned int queue_nr)
{
struct cs_etm_queue *etmq = queue->priv;
if (list_empty(&queue->head) || etmq)
return 0;
etmq = cs_etm__alloc_queue(etm, queue_nr);
if (!etmq)
return -ENOMEM;
queue->priv = etmq;
if (queue->cpu != -1)
etmq->cpu = queue->cpu;
etmq->tid = queue->tid;
return 0;
}
static int cs_etm__setup_queues(struct cs_etm_auxtrace *etm)
{
unsigned int i;
int ret;
for (i = 0; i < etm->queues.nr_queues; i++) {
ret = cs_etm__setup_queue(etm, &etm->queues.queue_array[i], i);
if (ret)
return ret;
}
return 0;
}
static int cs_etm__update_queues(struct cs_etm_auxtrace *etm)
{
if (etm->queues.new_data) {
etm->queues.new_data = false;
return cs_etm__setup_queues(etm);
}
return 0;
}
static inline void cs_etm__copy_last_branch_rb(struct cs_etm_queue *etmq)
{
struct branch_stack *bs_src = etmq->last_branch_rb;
struct branch_stack *bs_dst = etmq->last_branch;
size_t nr = 0;
/*
* Set the number of records before early exit: ->nr is used to
* determine how many branches to copy from ->entries.
*/
bs_dst->nr = bs_src->nr;
/*
* Early exit when there is nothing to copy.
*/
if (!bs_src->nr)
return;
/*
* As bs_src->entries is a circular buffer, we need to copy from it in
* two steps. First, copy the branches from the most recently inserted
* branch ->last_branch_pos until the end of bs_src->entries buffer.
*/
nr = etmq->etm->synth_opts.last_branch_sz - etmq->last_branch_pos;
memcpy(&bs_dst->entries[0],
&bs_src->entries[etmq->last_branch_pos],
sizeof(struct branch_entry) * nr);
/*
* If we wrapped around at least once, the branches from the beginning
* of the bs_src->entries buffer and until the ->last_branch_pos element
* are older valid branches: copy them over. The total number of
* branches copied over will be equal to the number of branches asked by
* the user in last_branch_sz.
*/
if (bs_src->nr >= etmq->etm->synth_opts.last_branch_sz) {
memcpy(&bs_dst->entries[nr],
&bs_src->entries[0],
sizeof(struct branch_entry) * etmq->last_branch_pos);
}
}
static inline void cs_etm__reset_last_branch_rb(struct cs_etm_queue *etmq)
{
etmq->last_branch_pos = 0;
etmq->last_branch_rb->nr = 0;
}
static inline int cs_etm__t32_instr_size(struct cs_etm_queue *etmq,
u64 addr) {
u8 instrBytes[2];
cs_etm__mem_access(etmq, addr, ARRAY_SIZE(instrBytes), instrBytes);
/*
* T32 instruction size is indicated by bits[15:11] of the first
* 16-bit word of the instruction: 0b11101, 0b11110 and 0b11111
* denote a 32-bit instruction.
*/
return ((instrBytes[1] & 0xF8) >= 0xE8) ? 4 : 2;
}
static inline u64 cs_etm__first_executed_instr(struct cs_etm_packet *packet)
{
/* Returns 0 for the CS_ETM_DISCONTINUITY packet */
if (packet->sample_type == CS_ETM_DISCONTINUITY)
return 0;
return packet->start_addr;
}
static inline
u64 cs_etm__last_executed_instr(const struct cs_etm_packet *packet)
{
/* Returns 0 for the CS_ETM_DISCONTINUITY packet */
if (packet->sample_type == CS_ETM_DISCONTINUITY)
return 0;
return packet->end_addr - packet->last_instr_size;
}
static inline u64 cs_etm__instr_addr(struct cs_etm_queue *etmq,
const struct cs_etm_packet *packet,
u64 offset)
{
if (packet->isa == CS_ETM_ISA_T32) {
u64 addr = packet->start_addr;
while (offset > 0) {
addr += cs_etm__t32_instr_size(etmq, addr);
offset--;
}
return addr;
}
/* Assume a 4 byte instruction size (A32/A64) */
return packet->start_addr + offset * 4;
}
static void cs_etm__update_last_branch_rb(struct cs_etm_queue *etmq)
{
struct branch_stack *bs = etmq->last_branch_rb;
struct branch_entry *be;
/*
* The branches are recorded in a circular buffer in reverse
* chronological order: we start recording from the last element of the
* buffer down. After writing the first element of the stack, move the
* insert position back to the end of the buffer.
*/
if (!etmq->last_branch_pos)
etmq->last_branch_pos = etmq->etm->synth_opts.last_branch_sz;
etmq->last_branch_pos -= 1;
be = &bs->entries[etmq->last_branch_pos];
be->from = cs_etm__last_executed_instr(etmq->prev_packet);
be->to = cs_etm__first_executed_instr(etmq->packet);
/* No support for mispredict */
be->flags.mispred = 0;
be->flags.predicted = 1;
/*
* Increment bs->nr until reaching the number of last branches asked by
* the user on the command line.
*/
if (bs->nr < etmq->etm->synth_opts.last_branch_sz)
bs->nr += 1;
}
static int cs_etm__inject_event(union perf_event *event,
struct perf_sample *sample, u64 type)
{
event->header.size = perf_event__sample_event_size(sample, type, 0);
return perf_event__synthesize_sample(event, type, 0, sample);
}
static int
cs_etm__get_trace(struct cs_etm_buffer *buff, struct cs_etm_queue *etmq)
{
struct auxtrace_buffer *aux_buffer = etmq->buffer;
struct auxtrace_buffer *old_buffer = aux_buffer;
struct auxtrace_queue *queue;
queue = &etmq->etm->queues.queue_array[etmq->queue_nr];
aux_buffer = auxtrace_buffer__next(queue, aux_buffer);
/* If no more data, drop the previous auxtrace_buffer and return */
if (!aux_buffer) {
if (old_buffer)
auxtrace_buffer__drop_data(old_buffer);
buff->len = 0;
return 0;
}
etmq->buffer = aux_buffer;
/* If the aux_buffer doesn't have data associated, try to load it */
if (!aux_buffer->data) {
/* get the file desc associated with the perf data file */
int fd = perf_data__fd(etmq->etm->session->data);
aux_buffer->data = auxtrace_buffer__get_data(aux_buffer, fd);
if (!aux_buffer->data)
return -ENOMEM;
}
/* If valid, drop the previous buffer */
if (old_buffer)
auxtrace_buffer__drop_data(old_buffer);
buff->offset = aux_buffer->offset;
buff->len = aux_buffer->size;
buff->buf = aux_buffer->data;
buff->ref_timestamp = aux_buffer->reference;
return buff->len;
}
static void cs_etm__set_pid_tid_cpu(struct cs_etm_auxtrace *etm,
struct auxtrace_queue *queue)
{
struct cs_etm_queue *etmq = queue->priv;
/* CPU-wide tracing isn't supported yet */
if (queue->tid == -1)
return;
if ((!etmq->thread) && (etmq->tid != -1))
etmq->thread = machine__find_thread(etm->machine, -1,
etmq->tid);
if (etmq->thread) {
etmq->pid = etmq->thread->pid_;
if (queue->cpu == -1)
etmq->cpu = etmq->thread->cpu;
}
}
static int cs_etm__synth_instruction_sample(struct cs_etm_queue *etmq,
u64 addr, u64 period)
{
int ret = 0;
struct cs_etm_auxtrace *etm = etmq->etm;
union perf_event *event = etmq->event_buf;
struct perf_sample sample = {.ip = 0,};
event->sample.header.type = PERF_RECORD_SAMPLE;
event->sample.header.misc = cs_etm__cpu_mode(etmq, addr);
event->sample.header.size = sizeof(struct perf_event_header);
sample.ip = addr;
sample.pid = etmq->pid;
sample.tid = etmq->tid;
sample.id = etmq->etm->instructions_id;
sample.stream_id = etmq->etm->instructions_id;
sample.period = period;
sample.cpu = etmq->packet->cpu;
sample.flags = 0;
sample.insn_len = 1;
sample.cpumode = event->sample.header.misc;
if (etm->synth_opts.last_branch) {
cs_etm__copy_last_branch_rb(etmq);
sample.branch_stack = etmq->last_branch;
}
if (etm->synth_opts.inject) {
ret = cs_etm__inject_event(event, &sample,
etm->instructions_sample_type);
if (ret)
return ret;
}
ret = perf_session__deliver_synth_event(etm->session, event, &sample);
if (ret)
pr_err(
"CS ETM Trace: failed to deliver instruction event, error %d\n",
ret);
if (etm->synth_opts.last_branch)
cs_etm__reset_last_branch_rb(etmq);
return ret;
}
/*
* The cs etm packet encodes an instruction range between a branch target
* and the next taken branch. Generate sample accordingly.
*/
static int cs_etm__synth_branch_sample(struct cs_etm_queue *etmq)
{
int ret = 0;
struct cs_etm_auxtrace *etm = etmq->etm;
struct perf_sample sample = {.ip = 0,};
union perf_event *event = etmq->event_buf;
struct dummy_branch_stack {
u64 nr;
struct branch_entry entries;
} dummy_bs;
u64 ip;
ip = cs_etm__last_executed_instr(etmq->prev_packet);
event->sample.header.type = PERF_RECORD_SAMPLE;
event->sample.header.misc = cs_etm__cpu_mode(etmq, ip);
event->sample.header.size = sizeof(struct perf_event_header);
sample.ip = ip;
sample.pid = etmq->pid;
sample.tid = etmq->tid;
sample.addr = cs_etm__first_executed_instr(etmq->packet);
sample.id = etmq->etm->branches_id;
sample.stream_id = etmq->etm->branches_id;
sample.period = 1;
sample.cpu = etmq->packet->cpu;
sample.flags = 0;
sample.cpumode = event->sample.header.misc;
/*
* perf report cannot handle events without a branch stack
*/
if (etm->synth_opts.last_branch) {
dummy_bs = (struct dummy_branch_stack){
.nr = 1,
.entries = {
.from = sample.ip,
.to = sample.addr,
},
};
sample.branch_stack = (struct branch_stack *)&dummy_bs;
}
if (etm->synth_opts.inject) {
ret = cs_etm__inject_event(event, &sample,
etm->branches_sample_type);
if (ret)
return ret;
}
ret = perf_session__deliver_synth_event(etm->session, event, &sample);
if (ret)
pr_err(
"CS ETM Trace: failed to deliver instruction event, error %d\n",
ret);
return ret;
}
struct cs_etm_synth {
struct perf_tool dummy_tool;
struct perf_session *session;
};
static int cs_etm__event_synth(struct perf_tool *tool,
union perf_event *event,
struct perf_sample *sample __maybe_unused,
struct machine *machine __maybe_unused)
{
struct cs_etm_synth *cs_etm_synth =
container_of(tool, struct cs_etm_synth, dummy_tool);
return perf_session__deliver_synth_event(cs_etm_synth->session,
event, NULL);
}
static int cs_etm__synth_event(struct perf_session *session,
struct perf_event_attr *attr, u64 id)
{
struct cs_etm_synth cs_etm_synth;
memset(&cs_etm_synth, 0, sizeof(struct cs_etm_synth));
cs_etm_synth.session = session;
return perf_event__synthesize_attr(&cs_etm_synth.dummy_tool, attr, 1,
&id, cs_etm__event_synth);
}
static int cs_etm__synth_events(struct cs_etm_auxtrace *etm,
struct perf_session *session)
{
struct perf_evlist *evlist = session->evlist;
struct perf_evsel *evsel;
struct perf_event_attr attr;
bool found = false;
u64 id;
int err;
evlist__for_each_entry(evlist, evsel) {
if (evsel->attr.type == etm->pmu_type) {
found = true;
break;
}
}
if (!found) {
pr_debug("No selected events with CoreSight Trace data\n");
return 0;
}
memset(&attr, 0, sizeof(struct perf_event_attr));
attr.size = sizeof(struct perf_event_attr);
attr.type = PERF_TYPE_HARDWARE;
attr.sample_type = evsel->attr.sample_type & PERF_SAMPLE_MASK;
attr.sample_type |= PERF_SAMPLE_IP | PERF_SAMPLE_TID |
PERF_SAMPLE_PERIOD;
if (etm->timeless_decoding)
attr.sample_type &= ~(u64)PERF_SAMPLE_TIME;
else
attr.sample_type |= PERF_SAMPLE_TIME;
attr.exclude_user = evsel->attr.exclude_user;
attr.exclude_kernel = evsel->attr.exclude_kernel;
attr.exclude_hv = evsel->attr.exclude_hv;
attr.exclude_host = evsel->attr.exclude_host;
attr.exclude_guest = evsel->attr.exclude_guest;
attr.sample_id_all = evsel->attr.sample_id_all;
attr.read_format = evsel->attr.read_format;
/* create new id val to be a fixed offset from evsel id */
id = evsel->id[0] + 1000000000;
if (!id)
id = 1;
if (etm->synth_opts.branches) {
attr.config = PERF_COUNT_HW_BRANCH_INSTRUCTIONS;
attr.sample_period = 1;
attr.sample_type |= PERF_SAMPLE_ADDR;
err = cs_etm__synth_event(session, &attr, id);
if (err)
return err;
etm->sample_branches = true;
etm->branches_sample_type = attr.sample_type;
etm->branches_id = id;
id += 1;
attr.sample_type &= ~(u64)PERF_SAMPLE_ADDR;
}
if (etm->synth_opts.last_branch)
attr.sample_type |= PERF_SAMPLE_BRANCH_STACK;
if (etm->synth_opts.instructions) {
attr.config = PERF_COUNT_HW_INSTRUCTIONS;
attr.sample_period = etm->synth_opts.period;
etm->instructions_sample_period = attr.sample_period;
err = cs_etm__synth_event(session, &attr, id);
if (err)
return err;
etm->sample_instructions = true;
etm->instructions_sample_type = attr.sample_type;
etm->instructions_id = id;
id += 1;
}
return 0;
}
static int cs_etm__sample(struct cs_etm_queue *etmq)
{
struct cs_etm_auxtrace *etm = etmq->etm;
struct cs_etm_packet *tmp;
int ret;
u64 instrs_executed = etmq->packet->instr_count;
etmq->period_instructions += instrs_executed;
/*
* Record a branch when the last instruction in
* PREV_PACKET is a branch.
*/
if (etm->synth_opts.last_branch &&
etmq->prev_packet &&
etmq->prev_packet->sample_type == CS_ETM_RANGE &&
etmq->prev_packet->last_instr_taken_branch)
cs_etm__update_last_branch_rb(etmq);
if (etm->sample_instructions &&
etmq->period_instructions >= etm->instructions_sample_period) {
/*
* Emit instruction sample periodically
* TODO: allow period to be defined in cycles and clock time
*/
/* Get number of instructions executed after the sample point */
u64 instrs_over = etmq->period_instructions -
etm->instructions_sample_period;
/*
* Calculate the address of the sampled instruction (-1 as
* sample is reported as though instruction has just been
* executed, but PC has not advanced to next instruction)
*/
u64 offset = (instrs_executed - instrs_over - 1);
u64 addr = cs_etm__instr_addr(etmq, etmq->packet, offset);
ret = cs_etm__synth_instruction_sample(
etmq, addr, etm->instructions_sample_period);
if (ret)
return ret;
/* Carry remaining instructions into next sample period */
etmq->period_instructions = instrs_over;
}
if (etm->sample_branches && etmq->prev_packet) {
bool generate_sample = false;
/* Generate sample for tracing on packet */
if (etmq->prev_packet->sample_type == CS_ETM_DISCONTINUITY)
generate_sample = true;
/* Generate sample for branch taken packet */
if (etmq->prev_packet->sample_type == CS_ETM_RANGE &&
etmq->prev_packet->last_instr_taken_branch)
generate_sample = true;
if (generate_sample) {
ret = cs_etm__synth_branch_sample(etmq);
if (ret)
return ret;
}
}
if (etm->sample_branches || etm->synth_opts.last_branch) {
/*
* Swap PACKET with PREV_PACKET: PACKET becomes PREV_PACKET for
* the next incoming packet.
*/
tmp = etmq->packet;
etmq->packet = etmq->prev_packet;
etmq->prev_packet = tmp;
}
return 0;
}
static int cs_etm__exception(struct cs_etm_queue *etmq)
{
/*
* When the exception packet is inserted, whether the last instruction
* in previous range packet is taken branch or not, we need to force
* to set 'prev_packet->last_instr_taken_branch' to true. This ensures
* to generate branch sample for the instruction range before the
* exception is trapped to kernel or before the exception returning.
*
* The exception packet includes the dummy address values, so don't
* swap PACKET with PREV_PACKET. This keeps PREV_PACKET to be useful
* for generating instruction and branch samples.
*/
if (etmq->prev_packet->sample_type == CS_ETM_RANGE)
etmq->prev_packet->last_instr_taken_branch = true;
return 0;
}
static int cs_etm__flush(struct cs_etm_queue *etmq)
{
int err = 0;
struct cs_etm_auxtrace *etm = etmq->etm;
struct cs_etm_packet *tmp;
if (!etmq->prev_packet)
return 0;
/* Handle start tracing packet */
if (etmq->prev_packet->sample_type == CS_ETM_EMPTY)
goto swap_packet;
if (etmq->etm->synth_opts.last_branch &&
etmq->prev_packet->sample_type == CS_ETM_RANGE) {
/*
* Generate a last branch event for the branches left in the
* circular buffer at the end of the trace.
*
* Use the address of the end of the last reported execution
* range
*/
u64 addr = cs_etm__last_executed_instr(etmq->prev_packet);
err = cs_etm__synth_instruction_sample(
etmq, addr,
etmq->period_instructions);
if (err)
return err;
etmq->period_instructions = 0;
}
if (etm->sample_branches &&
etmq->prev_packet->sample_type == CS_ETM_RANGE) {
err = cs_etm__synth_branch_sample(etmq);
if (err)
return err;
}
swap_packet:
if (etm->sample_branches || etm->synth_opts.last_branch) {
/*
* Swap PACKET with PREV_PACKET: PACKET becomes PREV_PACKET for
* the next incoming packet.
*/
tmp = etmq->packet;
etmq->packet = etmq->prev_packet;
etmq->prev_packet = tmp;
}
return err;
}
static int cs_etm__end_block(struct cs_etm_queue *etmq)
{
int err;
/*
* It has no new packet coming and 'etmq->packet' contains the stale
* packet which was set at the previous time with packets swapping;
* so skip to generate branch sample to avoid stale packet.
*
* For this case only flush branch stack and generate a last branch
* event for the branches left in the circular buffer at the end of
* the trace.
*/
if (etmq->etm->synth_opts.last_branch &&
etmq->prev_packet->sample_type == CS_ETM_RANGE) {
/*
* Use the address of the end of the last reported execution
* range.
*/
u64 addr = cs_etm__last_executed_instr(etmq->prev_packet);
err = cs_etm__synth_instruction_sample(
etmq, addr,
etmq->period_instructions);
if (err)
return err;
etmq->period_instructions = 0;
}
return 0;
}
static int cs_etm__run_decoder(struct cs_etm_queue *etmq)
{
struct cs_etm_auxtrace *etm = etmq->etm;
struct cs_etm_buffer buffer;
size_t buffer_used, processed;
int err = 0;
if (!etm->kernel_start)
etm->kernel_start = machine__kernel_start(etm->machine);
/* Go through each buffer in the queue and decode them one by one */
while (1) {
buffer_used = 0;
memset(&buffer, 0, sizeof(buffer));
err = cs_etm__get_trace(&buffer, etmq);
if (err <= 0)
return err;
/*
* We cannot assume consecutive blocks in the data file are
* contiguous, reset the decoder to force re-sync.
*/
err = cs_etm_decoder__reset(etmq->decoder);
if (err != 0)
return err;
/* Run trace decoder until buffer consumed or end of trace */
do {
processed = 0;
err = cs_etm_decoder__process_data_block(
etmq->decoder,
etmq->offset,
&buffer.buf[buffer_used],
buffer.len - buffer_used,
&processed);
if (err)
return err;
etmq->offset += processed;
buffer_used += processed;
/* Process each packet in this chunk */
while (1) {
err = cs_etm_decoder__get_packet(etmq->decoder,
etmq->packet);
if (err <= 0)
/*
* Stop processing this chunk on
* end of data or error
*/
break;
switch (etmq->packet->sample_type) {
case CS_ETM_RANGE:
/*
* If the packet contains an instruction
* range, generate instruction sequence
* events.
*/
cs_etm__sample(etmq);
break;
case CS_ETM_EXCEPTION:
case CS_ETM_EXCEPTION_RET:
/*
* If the exception packet is coming,
* make sure the previous instruction
* range packet to be handled properly.
*/
cs_etm__exception(etmq);
break;
case CS_ETM_DISCONTINUITY:
/*
* Discontinuity in trace, flush
* previous branch stack
*/
cs_etm__flush(etmq);
break;
case CS_ETM_EMPTY:
/*
* Should not receive empty packet,
* report error.
*/
pr_err("CS ETM Trace: empty packet\n");
return -EINVAL;
default:
break;
}
}
} while (buffer.len > buffer_used);
if (err == 0)
/* Flush any remaining branch stack entries */
err = cs_etm__end_block(etmq);
}
return err;
}
static int cs_etm__process_timeless_queues(struct cs_etm_auxtrace *etm,
pid_t tid, u64 time_)
{
unsigned int i;
struct auxtrace_queues *queues = &etm->queues;
for (i = 0; i < queues->nr_queues; i++) {
struct auxtrace_queue *queue = &etm->queues.queue_array[i];
struct cs_etm_queue *etmq = queue->priv;
if (etmq && ((tid == -1) || (etmq->tid == tid))) {
etmq->time = time_;
cs_etm__set_pid_tid_cpu(etm, queue);
cs_etm__run_decoder(etmq);
}
}
return 0;
}
static int cs_etm__process_event(struct perf_session *session,
union perf_event *event,
struct perf_sample *sample,
struct perf_tool *tool)
{
int err = 0;
u64 timestamp;
struct cs_etm_auxtrace *etm = container_of(session->auxtrace,
struct cs_etm_auxtrace,
auxtrace);
if (dump_trace)
return 0;
if (!tool->ordered_events) {
pr_err("CoreSight ETM Trace requires ordered events\n");
return -EINVAL;
}
if (!etm->timeless_decoding)
return -EINVAL;
if (sample->time && (sample->time != (u64) -1))
timestamp = sample->time;
else
timestamp = 0;
if (timestamp || etm->timeless_decoding) {
err = cs_etm__update_queues(etm);
if (err)
return err;
}
if (event->header.type == PERF_RECORD_EXIT)
return cs_etm__process_timeless_queues(etm,
event->fork.tid,
sample->time);
return 0;
}
static int cs_etm__process_auxtrace_event(struct perf_session *session,
union perf_event *event,
struct perf_tool *tool __maybe_unused)
{
struct cs_etm_auxtrace *etm = container_of(session->auxtrace,
struct cs_etm_auxtrace,
auxtrace);
if (!etm->data_queued) {
struct auxtrace_buffer *buffer;
off_t data_offset;
int fd = perf_data__fd(session->data);
bool is_pipe = perf_data__is_pipe(session->data);
int err;
if (is_pipe)
data_offset = 0;
else {
data_offset = lseek(fd, 0, SEEK_CUR);
if (data_offset == -1)
return -errno;
}
err = auxtrace_queues__add_event(&etm->queues, session,
event, data_offset, &buffer);
if (err)
return err;
if (dump_trace)
if (auxtrace_buffer__get_data(buffer, fd)) {
cs_etm__dump_event(etm, buffer);
auxtrace_buffer__put_data(buffer);
}
}
return 0;
}
static bool cs_etm__is_timeless_decoding(struct cs_etm_auxtrace *etm)
{
struct perf_evsel *evsel;
struct perf_evlist *evlist = etm->session->evlist;
bool timeless_decoding = true;
/*
* Circle through the list of event and complain if we find one
* with the time bit set.
*/
evlist__for_each_entry(evlist, evsel) {
if ((evsel->attr.sample_type & PERF_SAMPLE_TIME))
timeless_decoding = false;
}
return timeless_decoding;
}
static const char * const cs_etm_global_header_fmts[] = {
[CS_HEADER_VERSION_0] = " Header version %llx\n",
[CS_PMU_TYPE_CPUS] = " PMU type/num cpus %llx\n",
[CS_ETM_SNAPSHOT] = " Snapshot %llx\n",
};
static const char * const cs_etm_priv_fmts[] = {
[CS_ETM_MAGIC] = " Magic number %llx\n",
[CS_ETM_CPU] = " CPU %lld\n",
[CS_ETM_ETMCR] = " ETMCR %llx\n",
[CS_ETM_ETMTRACEIDR] = " ETMTRACEIDR %llx\n",
[CS_ETM_ETMCCER] = " ETMCCER %llx\n",
[CS_ETM_ETMIDR] = " ETMIDR %llx\n",
};
static const char * const cs_etmv4_priv_fmts[] = {
[CS_ETM_MAGIC] = " Magic number %llx\n",
[CS_ETM_CPU] = " CPU %lld\n",
[CS_ETMV4_TRCCONFIGR] = " TRCCONFIGR %llx\n",
[CS_ETMV4_TRCTRACEIDR] = " TRCTRACEIDR %llx\n",
[CS_ETMV4_TRCIDR0] = " TRCIDR0 %llx\n",
[CS_ETMV4_TRCIDR1] = " TRCIDR1 %llx\n",
[CS_ETMV4_TRCIDR2] = " TRCIDR2 %llx\n",
[CS_ETMV4_TRCIDR8] = " TRCIDR8 %llx\n",
[CS_ETMV4_TRCAUTHSTATUS] = " TRCAUTHSTATUS %llx\n",
};
static void cs_etm__print_auxtrace_info(u64 *val, int num)
{
int i, j, cpu = 0;
for (i = 0; i < CS_HEADER_VERSION_0_MAX; i++)
fprintf(stdout, cs_etm_global_header_fmts[i], val[i]);
for (i = CS_HEADER_VERSION_0_MAX; cpu < num; cpu++) {
if (val[i] == __perf_cs_etmv3_magic)
for (j = 0; j < CS_ETM_PRIV_MAX; j++, i++)
fprintf(stdout, cs_etm_priv_fmts[j], val[i]);
else if (val[i] == __perf_cs_etmv4_magic)
for (j = 0; j < CS_ETMV4_PRIV_MAX; j++, i++)
fprintf(stdout, cs_etmv4_priv_fmts[j], val[i]);
else
/* failure.. return */
return;
}
}
int cs_etm__process_auxtrace_info(union perf_event *event,
struct perf_session *session)
{
struct auxtrace_info_event *auxtrace_info = &event->auxtrace_info;
struct cs_etm_auxtrace *etm = NULL;
struct int_node *inode;
unsigned int pmu_type;
int event_header_size = sizeof(struct perf_event_header);
int info_header_size;
int total_size = auxtrace_info->header.size;
int priv_size = 0;
int num_cpu;
int err = 0, idx = -1;
int i, j, k;
u64 *ptr, *hdr = NULL;
u64 **metadata = NULL;
/*
* sizeof(auxtrace_info_event::type) +
* sizeof(auxtrace_info_event::reserved) == 8
*/
info_header_size = 8;
if (total_size < (event_header_size + info_header_size))
return -EINVAL;
priv_size = total_size - event_header_size - info_header_size;
/* First the global part */
ptr = (u64 *) auxtrace_info->priv;
/* Look for version '0' of the header */
if (ptr[0] != 0)
return -EINVAL;
hdr = zalloc(sizeof(*hdr) * CS_HEADER_VERSION_0_MAX);
if (!hdr)
return -ENOMEM;
/* Extract header information - see cs-etm.h for format */
for (i = 0; i < CS_HEADER_VERSION_0_MAX; i++)
hdr[i] = ptr[i];
num_cpu = hdr[CS_PMU_TYPE_CPUS] & 0xffffffff;
pmu_type = (unsigned int) ((hdr[CS_PMU_TYPE_CPUS] >> 32) &
0xffffffff);
/*
* Create an RB tree for traceID-CPU# tuple. Since the conversion has
* to be made for each packet that gets decoded, optimizing access in
* anything other than a sequential array is worth doing.
*/
traceid_list = intlist__new(NULL);
if (!traceid_list) {
err = -ENOMEM;
goto err_free_hdr;
}
metadata = zalloc(sizeof(*metadata) * num_cpu);
if (!metadata) {
err = -ENOMEM;
goto err_free_traceid_list;
}
/*
* The metadata is stored in the auxtrace_info section and encodes
* the configuration of the ARM embedded trace macrocell which is
* required by the trace decoder to properly decode the trace due
* to its highly compressed nature.
*/
for (j = 0; j < num_cpu; j++) {
if (ptr[i] == __perf_cs_etmv3_magic) {
metadata[j] = zalloc(sizeof(*metadata[j]) *
CS_ETM_PRIV_MAX);
if (!metadata[j]) {
err = -ENOMEM;
goto err_free_metadata;
}
for (k = 0; k < CS_ETM_PRIV_MAX; k++)
metadata[j][k] = ptr[i + k];
/* The traceID is our handle */
idx = metadata[j][CS_ETM_ETMTRACEIDR];
i += CS_ETM_PRIV_MAX;
} else if (ptr[i] == __perf_cs_etmv4_magic) {
metadata[j] = zalloc(sizeof(*metadata[j]) *
CS_ETMV4_PRIV_MAX);
if (!metadata[j]) {
err = -ENOMEM;
goto err_free_metadata;
}
for (k = 0; k < CS_ETMV4_PRIV_MAX; k++)
metadata[j][k] = ptr[i + k];
/* The traceID is our handle */
idx = metadata[j][CS_ETMV4_TRCTRACEIDR];
i += CS_ETMV4_PRIV_MAX;
}
/* Get an RB node for this CPU */
inode = intlist__findnew(traceid_list, idx);
/* Something went wrong, no need to continue */
if (!inode) {
err = PTR_ERR(inode);
goto err_free_metadata;
}
/*
* The node for that CPU should not be taken.
* Back out if that's the case.
*/
if (inode->priv) {
err = -EINVAL;
goto err_free_metadata;
}
/* All good, associate the traceID with the CPU# */
inode->priv = &metadata[j][CS_ETM_CPU];
}
/*
* Each of CS_HEADER_VERSION_0_MAX, CS_ETM_PRIV_MAX and
* CS_ETMV4_PRIV_MAX mark how many double words are in the
* global metadata, and each cpu's metadata respectively.
* The following tests if the correct number of double words was
* present in the auxtrace info section.
*/
if (i * 8 != priv_size) {
err = -EINVAL;
goto err_free_metadata;
}
etm = zalloc(sizeof(*etm));
if (!etm) {
err = -ENOMEM;
goto err_free_metadata;
}
err = auxtrace_queues__init(&etm->queues);
if (err)
goto err_free_etm;
etm->session = session;
etm->machine = &session->machines.host;
etm->num_cpu = num_cpu;
etm->pmu_type = pmu_type;
etm->snapshot_mode = (hdr[CS_ETM_SNAPSHOT] != 0);
etm->metadata = metadata;
etm->auxtrace_type = auxtrace_info->type;
etm->timeless_decoding = cs_etm__is_timeless_decoding(etm);
etm->auxtrace.process_event = cs_etm__process_event;
etm->auxtrace.process_auxtrace_event = cs_etm__process_auxtrace_event;
etm->auxtrace.flush_events = cs_etm__flush_events;
etm->auxtrace.free_events = cs_etm__free_events;
etm->auxtrace.free = cs_etm__free;
session->auxtrace = &etm->auxtrace;
etm->unknown_thread = thread__new(999999999, 999999999);
if (!etm->unknown_thread)
goto err_free_queues;
/*
* Initialize list node so that at thread__zput() we can avoid
* segmentation fault at list_del_init().
*/
INIT_LIST_HEAD(&etm->unknown_thread->node);
err = thread__set_comm(etm->unknown_thread, "unknown", 0);
if (err)
goto err_delete_thread;
if (thread__init_map_groups(etm->unknown_thread, etm->machine))
goto err_delete_thread;
if (dump_trace) {
cs_etm__print_auxtrace_info(auxtrace_info->priv, num_cpu);
return 0;
}
if (session->itrace_synth_opts && session->itrace_synth_opts->set) {
etm->synth_opts = *session->itrace_synth_opts;
} else {
itrace_synth_opts__set_default(&etm->synth_opts,
session->itrace_synth_opts->default_no_sample);
etm->synth_opts.callchain = false;
}
err = cs_etm__synth_events(etm, session);
if (err)
goto err_delete_thread;
err = auxtrace_queues__process_index(&etm->queues, session);
if (err)
goto err_delete_thread;
etm->data_queued = etm->queues.populated;
return 0;
err_delete_thread:
thread__zput(etm->unknown_thread);
err_free_queues:
auxtrace_queues__free(&etm->queues);
session->auxtrace = NULL;
err_free_etm:
zfree(&etm);
err_free_metadata:
/* No need to check @metadata[j], free(NULL) is supported */
for (j = 0; j < num_cpu; j++)
free(metadata[j]);
zfree(&metadata);
err_free_traceid_list:
intlist__delete(traceid_list);
err_free_hdr:
zfree(&hdr);
return -EINVAL;
}