LXR linux/tools/perf/arch/arm/util/auxtrace.c

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright(C) 2015 Linaro Limited. All rights reserved.
   4 * Author: Mathieu Poirier <mathieu.poirier@linaro.org>
   5 */
   6
   7#include <stdbool.h>
   8#include <linux/coresight-pmu.h>
   9#include <linux/zalloc.h>
  10
  11#include "../../../util/auxtrace.h"
  12#include "../../../util/debug.h"
  13#include "../../../util/evlist.h"
  14#include "../../../util/pmu.h"
  15#include "cs-etm.h"
  16#include "arm-spe.h"
  17
  18static struct perf_pmu **find_all_arm_spe_pmus(int *nr_spes, int *err)
  19{
  20        struct perf_pmu **arm_spe_pmus = NULL;
  21        int ret, i, nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
  22        /* arm_spe_xxxxxxxxx\0 */
  23        char arm_spe_pmu_name[sizeof(ARM_SPE_PMU_NAME) + 10];
  24
  25        arm_spe_pmus = zalloc(sizeof(struct perf_pmu *) * nr_cpus);
  26        if (!arm_spe_pmus) {
  27                pr_err("spes alloc failed\n");
  28                *err = -ENOMEM;
  29                return NULL;
  30        }
  31
  32        for (i = 0; i < nr_cpus; i++) {
  33                ret = sprintf(arm_spe_pmu_name, "%s%d", ARM_SPE_PMU_NAME, i);
  34                if (ret < 0) {
  35                        pr_err("sprintf failed\n");
  36                        *err = -ENOMEM;
  37                        return NULL;
  38                }
  39
  40                arm_spe_pmus[*nr_spes] = perf_pmu__find(arm_spe_pmu_name);
  41                if (arm_spe_pmus[*nr_spes]) {
  42                        pr_debug2("%s %d: arm_spe_pmu %d type %d name %s\n",
  43                                 __func__, __LINE__, *nr_spes,
  44                                 arm_spe_pmus[*nr_spes]->type,
  45                                 arm_spe_pmus[*nr_spes]->name);
  46                        (*nr_spes)++;
  47                }
  48        }
  49
  50        return arm_spe_pmus;
  51}
  52
  53struct auxtrace_record
  54*auxtrace_record__init(struct evlist *evlist, int *err)
  55{
  56        struct perf_pmu *cs_etm_pmu;
  57        struct evsel *evsel;
  58        bool found_etm = false;
  59        struct perf_pmu *found_spe = NULL;
  60        struct perf_pmu **arm_spe_pmus = NULL;
  61        int nr_spes = 0;
  62        int i = 0;
  63
  64        if (!evlist)
  65                return NULL;
  66
  67        cs_etm_pmu = perf_pmu__find(CORESIGHT_ETM_PMU_NAME);
  68        arm_spe_pmus = find_all_arm_spe_pmus(&nr_spes, err);
  69
  70        evlist__for_each_entry(evlist, evsel) {
  71                if (cs_etm_pmu &&
  72                    evsel->core.attr.type == cs_etm_pmu->type)
  73                        found_etm = true;
  74
  75                if (!nr_spes || found_spe)
  76                        continue;
  77
  78                for (i = 0; i < nr_spes; i++) {
  79                        if (evsel->core.attr.type == arm_spe_pmus[i]->type) {
  80                                found_spe = arm_spe_pmus[i];
  81                                break;
  82                        }
  83                }
  84        }
  85        free(arm_spe_pmus);
  86
  87        if (found_etm && found_spe) {
  88                pr_err("Concurrent ARM Coresight ETM and SPE operation not currently supported\n");
  89                *err = -EOPNOTSUPP;
  90                return NULL;
  91        }
  92
  93        if (found_etm)
  94                return cs_etm_record_init(err);
  95
  96#if defined(__aarch64__)
  97        if (found_spe)
  98                return arm_spe_recording_init(err, found_spe);
  99#endif
 100
 101        /*
 102         * Clear 'err' even if we haven't found an event - that way perf
 103         * record can still be used even if tracers aren't present.  The NULL
 104         * return value will take care of telling the infrastructure HW tracing
 105         * isn't available.
 106         */
 107        *err = 0;
 108        return NULL;
 109}
 110
 111#if defined(__arm__)
 112u64 compat_auxtrace_mmap__read_head(struct auxtrace_mmap *mm)
 113{
 114        struct perf_event_mmap_page *pc = mm->userpg;
 115        u64 result;
 116
 117        __asm__ __volatile__(
 118"       ldrd    %0, %H0, [%1]"
 119        : "=&r" (result)
 120        : "r" (&pc->aux_head), "Qo" (pc->aux_head)
 121        );
 122
 123        return result;
 124}
 125
 126int compat_auxtrace_mmap__write_tail(struct auxtrace_mmap *mm, u64 tail)
 127{
 128        struct perf_event_mmap_page *pc = mm->userpg;
 129
 130        /* Ensure all reads are done before we write the tail out */
 131        smp_mb();
 132
 133        __asm__ __volatile__(
 134"       strd    %2, %H2, [%1]"
 135        : "=Qo" (pc->aux_tail)
 136        : "r" (&pc->aux_tail), "r" (tail)
 137        );
 138
 139        return 0;
 140}
 141#endif
 142