linux/tools/perf/arch/arm64/util/arm-spe.c
Kim Phillips 3443533665 perf arm spe: Fix uninitialized record error variable
The auxtrace init variable 'err' was not being initialized, leading perf
to abort early in an SPE record command when there was no explicit
error, rather only based whatever memory contents were on the stack.
Initialize it explicitly on getting an SPE successfully, the same way
cs-etm does.

Signed-off-by: Kim Phillips <kim.phillips@arm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Dongjiu Geng <gengdongjiu@huawei.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes: ffd3d18c20 ("perf tools: Add ARM Statistical Profiling Extensions (SPE) support")
Link: http://lkml.kernel.org/r/20180810174512.52900813e57cbccf18ce99a2@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-08-14 15:10:44 -03:00

227 lines
5.7 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Arm Statistical Profiling Extensions (SPE) support
* Copyright (c) 2017-2018, Arm Ltd.
*/
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/bitops.h>
#include <linux/log2.h>
#include <time.h>
#include "../../util/cpumap.h"
#include "../../util/evsel.h"
#include "../../util/evlist.h"
#include "../../util/session.h"
#include "../../util/util.h"
#include "../../util/pmu.h"
#include "../../util/debug.h"
#include "../../util/auxtrace.h"
#include "../../util/arm-spe.h"
#define KiB(x) ((x) * 1024)
#define MiB(x) ((x) * 1024 * 1024)
struct arm_spe_recording {
struct auxtrace_record itr;
struct perf_pmu *arm_spe_pmu;
struct perf_evlist *evlist;
};
static size_t
arm_spe_info_priv_size(struct auxtrace_record *itr __maybe_unused,
struct perf_evlist *evlist __maybe_unused)
{
return ARM_SPE_AUXTRACE_PRIV_SIZE;
}
static int arm_spe_info_fill(struct auxtrace_record *itr,
struct perf_session *session,
struct auxtrace_info_event *auxtrace_info,
size_t priv_size)
{
struct arm_spe_recording *sper =
container_of(itr, struct arm_spe_recording, itr);
struct perf_pmu *arm_spe_pmu = sper->arm_spe_pmu;
if (priv_size != ARM_SPE_AUXTRACE_PRIV_SIZE)
return -EINVAL;
if (!session->evlist->nr_mmaps)
return -EINVAL;
auxtrace_info->type = PERF_AUXTRACE_ARM_SPE;
auxtrace_info->priv[ARM_SPE_PMU_TYPE] = arm_spe_pmu->type;
return 0;
}
static int arm_spe_recording_options(struct auxtrace_record *itr,
struct perf_evlist *evlist,
struct record_opts *opts)
{
struct arm_spe_recording *sper =
container_of(itr, struct arm_spe_recording, itr);
struct perf_pmu *arm_spe_pmu = sper->arm_spe_pmu;
struct perf_evsel *evsel, *arm_spe_evsel = NULL;
bool privileged = geteuid() == 0 || perf_event_paranoid() < 0;
struct perf_evsel *tracking_evsel;
int err;
sper->evlist = evlist;
evlist__for_each_entry(evlist, evsel) {
if (evsel->attr.type == arm_spe_pmu->type) {
if (arm_spe_evsel) {
pr_err("There may be only one " ARM_SPE_PMU_NAME "x event\n");
return -EINVAL;
}
evsel->attr.freq = 0;
evsel->attr.sample_period = 1;
arm_spe_evsel = evsel;
opts->full_auxtrace = true;
}
}
if (!opts->full_auxtrace)
return 0;
/* We are in full trace mode but '-m,xyz' wasn't specified */
if (opts->full_auxtrace && !opts->auxtrace_mmap_pages) {
if (privileged) {
opts->auxtrace_mmap_pages = MiB(4) / page_size;
} else {
opts->auxtrace_mmap_pages = KiB(128) / page_size;
if (opts->mmap_pages == UINT_MAX)
opts->mmap_pages = KiB(256) / page_size;
}
}
/* Validate auxtrace_mmap_pages */
if (opts->auxtrace_mmap_pages) {
size_t sz = opts->auxtrace_mmap_pages * (size_t)page_size;
size_t min_sz = KiB(8);
if (sz < min_sz || !is_power_of_2(sz)) {
pr_err("Invalid mmap size for ARM SPE: must be at least %zuKiB and a power of 2\n",
min_sz / 1024);
return -EINVAL;
}
}
/*
* To obtain the auxtrace buffer file descriptor, the auxtrace event
* must come first.
*/
perf_evlist__to_front(evlist, arm_spe_evsel);
perf_evsel__set_sample_bit(arm_spe_evsel, CPU);
perf_evsel__set_sample_bit(arm_spe_evsel, TIME);
perf_evsel__set_sample_bit(arm_spe_evsel, TID);
/* Add dummy event to keep tracking */
err = parse_events(evlist, "dummy:u", NULL);
if (err)
return err;
tracking_evsel = perf_evlist__last(evlist);
perf_evlist__set_tracking_event(evlist, tracking_evsel);
tracking_evsel->attr.freq = 0;
tracking_evsel->attr.sample_period = 1;
perf_evsel__set_sample_bit(tracking_evsel, TIME);
perf_evsel__set_sample_bit(tracking_evsel, CPU);
perf_evsel__reset_sample_bit(tracking_evsel, BRANCH_STACK);
return 0;
}
static u64 arm_spe_reference(struct auxtrace_record *itr __maybe_unused)
{
struct timespec ts;
clock_gettime(CLOCK_MONOTONIC_RAW, &ts);
return ts.tv_sec ^ ts.tv_nsec;
}
static void arm_spe_recording_free(struct auxtrace_record *itr)
{
struct arm_spe_recording *sper =
container_of(itr, struct arm_spe_recording, itr);
free(sper);
}
static int arm_spe_read_finish(struct auxtrace_record *itr, int idx)
{
struct arm_spe_recording *sper =
container_of(itr, struct arm_spe_recording, itr);
struct perf_evsel *evsel;
evlist__for_each_entry(sper->evlist, evsel) {
if (evsel->attr.type == sper->arm_spe_pmu->type)
return perf_evlist__enable_event_idx(sper->evlist,
evsel, idx);
}
return -EINVAL;
}
struct auxtrace_record *arm_spe_recording_init(int *err,
struct perf_pmu *arm_spe_pmu)
{
struct arm_spe_recording *sper;
if (!arm_spe_pmu) {
*err = -ENODEV;
return NULL;
}
sper = zalloc(sizeof(struct arm_spe_recording));
if (!sper) {
*err = -ENOMEM;
return NULL;
}
sper->arm_spe_pmu = arm_spe_pmu;
sper->itr.recording_options = arm_spe_recording_options;
sper->itr.info_priv_size = arm_spe_info_priv_size;
sper->itr.info_fill = arm_spe_info_fill;
sper->itr.free = arm_spe_recording_free;
sper->itr.reference = arm_spe_reference;
sper->itr.read_finish = arm_spe_read_finish;
sper->itr.alignment = 0;
*err = 0;
return &sper->itr;
}
struct perf_event_attr
*arm_spe_pmu_default_config(struct perf_pmu *arm_spe_pmu)
{
struct perf_event_attr *attr;
attr = zalloc(sizeof(struct perf_event_attr));
if (!attr) {
pr_err("arm_spe default config cannot allocate a perf_event_attr\n");
return NULL;
}
/*
* If kernel driver doesn't advertise a minimum,
* use max allowable by PMSIDR_EL1.INTERVAL
*/
if (perf_pmu__scan_file(arm_spe_pmu, "caps/min_interval", "%llu",
&attr->sample_period) != 1) {
pr_debug("arm_spe driver doesn't advertise a min. interval. Using 4096\n");
attr->sample_period = 4096;
}
arm_spe_pmu->selectable = true;
arm_spe_pmu->is_uncore = false;
return attr;
}