mirror of
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2025-08-05 16:54:27 +00:00
5b546de9cc
The string comparisons were overly broad and could fire for the
incorrect PMU and events. Switch to using the config in the attribute
then add a perf test to confirm the attribute config values match
those of parsed events of that name and don't match others. This
exposed matches for slots events that shouldn't have matched as the
slots fixed counter event, such as topdown.slots_p.
Fixes: fbc798316b ("perf x86/topdown: Refine helper arch_is_topdown_metrics()")
Signed-off-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20250719030517.1990983-14-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
123 lines
3.4 KiB
C
123 lines
3.4 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 "util/pmus.h"
|
|
#include "linux/string.h"
|
|
#include "topdown.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);
|
|
}
|
|
|
|
/* Check whether the evsel's PMU supports the perf metrics */
|
|
bool evsel__sys_has_perf_metrics(const struct evsel *evsel)
|
|
{
|
|
struct perf_pmu *pmu;
|
|
|
|
if (!topdown_sys_has_perf_metrics())
|
|
return false;
|
|
|
|
/*
|
|
* 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
|
|
* topdown_sys_has_perf_metrics checks 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.
|
|
*/
|
|
pmu = evsel__find_pmu(evsel);
|
|
return pmu && pmu->type == PERF_TYPE_RAW;
|
|
}
|
|
|
|
bool arch_evsel__must_be_in_group(const struct evsel *evsel)
|
|
{
|
|
if (!evsel__sys_has_perf_metrics(evsel))
|
|
return false;
|
|
|
|
return arch_is_topdown_metrics(evsel) || arch_is_topdown_slots(evsel);
|
|
}
|
|
|
|
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 ? 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_pmus__find("ibs_fetch");
|
|
ibs_op_pmu = perf_pmus__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;
|
|
}
|
|
}
|
|
}
|
|
|
|
int arch_evsel__open_strerror(struct evsel *evsel, char *msg, size_t size)
|
|
{
|
|
if (!x86__is_amd_cpu())
|
|
return 0;
|
|
|
|
if (!evsel->core.attr.precise_ip &&
|
|
!(evsel->pmu && !strncmp(evsel->pmu->name, "ibs", 3)))
|
|
return 0;
|
|
|
|
/* More verbose IBS errors. */
|
|
if (evsel->core.attr.exclude_kernel || evsel->core.attr.exclude_user ||
|
|
evsel->core.attr.exclude_hv || evsel->core.attr.exclude_idle ||
|
|
evsel->core.attr.exclude_host || evsel->core.attr.exclude_guest) {
|
|
return scnprintf(msg, size, "AMD IBS doesn't support privilege filtering. Try "
|
|
"again without the privilege modifiers (like 'k') at the end.");
|
|
}
|
|
|
|
return 0;
|
|
}
|