linuxdebug/tools/perf/arch/x86/util/evsel.c

124 lines
3.3 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <stdio.h>
#include <stdlib.h>
#include "util/evsel.h"
#include "util/env.h"
#include "util/pmu.h"
#include "linux/string.h"
#include "evsel.h"
#include "util/debug.h"
#include "env.h"
#define IBS_FETCH_L3MISSONLY (1ULL << 59)
#define IBS_OP_L3MISSONLY (1ULL << 16)
void arch_evsel__set_sample_weight(struct evsel *evsel)
{
evsel__set_sample_bit(evsel, WEIGHT_STRUCT);
}
void arch_evsel__fixup_new_cycles(struct perf_event_attr *attr)
{
struct perf_env env = { .total_mem = 0, } ;
if (!perf_env__cpuid(&env))
return;
/*
* On AMD, precise cycles event sampling internally uses IBS pmu.
* But IBS does not have filtering capabilities and perf by default
* sets exclude_guest = 1. This makes IBS pmu event init fail and
* thus perf ends up doing non-precise sampling. Avoid it by clearing
* exclude_guest.
*/
if (env.cpuid && strstarts(env.cpuid, "AuthenticAMD"))
attr->exclude_guest = 0;
free(env.cpuid);
}
/* Check whether the evsel's PMU supports the perf metrics */
bool evsel__sys_has_perf_metrics(const struct evsel *evsel)
{
const char *pmu_name = evsel->pmu_name ? evsel->pmu_name : "cpu";
/*
* The PERF_TYPE_RAW type is the core PMU type, e.g., "cpu" PMU
* on a non-hybrid machine, "cpu_core" PMU on a hybrid machine.
* The slots event is only available for the core PMU, which
* supports the perf metrics feature.
* Checking both the PERF_TYPE_RAW type and the slots event
* should be good enough to detect the perf metrics feature.
*/
if ((evsel->core.attr.type == PERF_TYPE_RAW) &&
pmu_have_event(pmu_name, "slots"))
return true;
return false;
}
bool arch_evsel__must_be_in_group(const struct evsel *evsel)
{
if (!evsel__sys_has_perf_metrics(evsel))
return false;
return evsel->name &&
(strcasestr(evsel->name, "slots") ||
strcasestr(evsel->name, "topdown"));
}
int arch_evsel__hw_name(struct evsel *evsel, char *bf, size_t size)
{
u64 event = evsel->core.attr.config & PERF_HW_EVENT_MASK;
u64 pmu = evsel->core.attr.config >> PERF_PMU_TYPE_SHIFT;
const char *event_name;
if (event < PERF_COUNT_HW_MAX && evsel__hw_names[event])
event_name = evsel__hw_names[event];
else
event_name = "unknown-hardware";
/* The PMU type is not required for the non-hybrid platform. */
if (!pmu)
return scnprintf(bf, size, "%s", event_name);
return scnprintf(bf, size, "%s/%s/",
evsel->pmu_name ? evsel->pmu_name : "cpu",
event_name);
}
static void ibs_l3miss_warn(void)
{
pr_warning(
"WARNING: Hw internally resets sampling period when L3 Miss Filtering is enabled\n"
"and tagged operation does not cause L3 Miss. This causes sampling period skew.\n");
}
void arch__post_evsel_config(struct evsel *evsel, struct perf_event_attr *attr)
{
struct perf_pmu *evsel_pmu, *ibs_fetch_pmu, *ibs_op_pmu;
static int warned_once;
if (warned_once || !x86__is_amd_cpu())
return;
evsel_pmu = evsel__find_pmu(evsel);
if (!evsel_pmu)
return;
ibs_fetch_pmu = perf_pmu__find("ibs_fetch");
ibs_op_pmu = perf_pmu__find("ibs_op");
if (ibs_fetch_pmu && ibs_fetch_pmu->type == evsel_pmu->type) {
if (attr->config & IBS_FETCH_L3MISSONLY) {
ibs_l3miss_warn();
warned_once = 1;
}
} else if (ibs_op_pmu && ibs_op_pmu->type == evsel_pmu->type) {
if (attr->config & IBS_OP_L3MISSONLY) {
ibs_l3miss_warn();
warned_once = 1;
}
}
}