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
  18 static 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
  53 static struct perf_pmu *find_pmu_for_event(struct perf_pmu **pmus,
  54                                            int pmu_nr, struct evsel *evsel)
  55 {
  56         int i;
  57
  58         if (!pmus)
  59                 return NULL;
  60
  61         for (i = 0; i < pmu_nr; i++) {
  62                 if (evsel->core.attr.type == pmus[i]->type)
  63                         return pmus[i];
  64         }
  65
  66         return NULL;
  67 }
  68
  69 struct auxtrace_record
  70 *auxtrace_record__init(struct evlist *evlist, int *err)
  71 {
  72         struct perf_pmu *cs_etm_pmu = NULL;
  73         struct perf_pmu **arm_spe_pmus = NULL;
  74         struct evsel *evsel;
  75         struct perf_pmu *found_etm = NULL;
  76         struct perf_pmu *found_spe = NULL;
  77         int auxtrace_event_cnt = 0;
  78         int nr_spes = 0;
  79
  80         if (!evlist)
  81                 return NULL;
  82
  83         cs_etm_pmu = perf_pmu__find(CORESIGHT_ETM_PMU_NAME);
  84         arm_spe_pmus = find_all_arm_spe_pmus(&nr_spes, err);
  85
  86         evlist__for_each_entry(evlist, evsel) {
  87                 if (cs_etm_pmu && !found_etm)
  88                         found_etm = find_pmu_for_event(&cs_etm_pmu, 1, evsel);
  89
  90                 if (arm_spe_pmus && !found_spe)
  91                         found_spe = find_pmu_for_event(arm_spe_pmus, nr_spes, evsel);
  92         }
  93
  94         free(arm_spe_pmus);
  95
  96         if (found_etm)
  97                 auxtrace_event_cnt++;
  98
  99         if (found_spe)
 100                 auxtrace_event_cnt++;
 101
 102         if (auxtrace_event_cnt > 1) {
 103                 pr_err("Concurrent AUX trace operation not currently supported\n");
 104                 *err = -EOPNOTSUPP;
 105                 return NULL;
 106         }
 107
 108         if (found_etm)
 109                 return cs_etm_record_init(err);
 110
 111 #if defined(__aarch64__)
 112         if (found_spe)
 113                 return arm_spe_recording_init(err, found_spe);
 114 #endif
 115
 116         /*
 117          * Clear 'err' even if we haven't found an event - that way perf
 118          * record can still be used even if tracers aren't present.  The NULL
 119          * return value will take care of telling the infrastructure HW tracing
 120          * isn't available.
 121          */
 122         *err = 0;
 123         return NULL;
 124 }
 125
 126 #if defined(__arm__)
 127 u64 compat_auxtrace_mmap__read_head(struct auxtrace_mmap *mm)
 128 {
 129         struct perf_event_mmap_page *pc = mm->userpg;
 130         u64 result;
 131
 132         __asm__ __volatile__(
 133 "       ldrd    %0, %H0, [%1]"
 134         : "=&r" (result)
 135         : "r" (&pc->aux_head), "Qo" (pc->aux_head)
 136         );
 137
 138         return result;
 139 }
 140
 141 int compat_auxtrace_mmap__write_tail(struct auxtrace_mmap *mm, u64 tail)
 142 {
 143         struct perf_event_mmap_page *pc = mm->userpg;
 144
 145         /* Ensure all reads are done before we write the tail out */
 146         smp_mb();
 147
 148         __asm__ __volatile__(
 149 "       strd    %2, %H2, [%1]"
 150         : "=Qo" (pc->aux_tail)
 151         : "r" (&pc->aux_tail), "r" (tail)
 152         );
 153
 154         return 0;
 155 }
 156 #endif