1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Arm Statistical Profiling Extensions (SPE) support 4 * Copyright (c) 2017-2018, Arm Ltd. 5 */ 6 7 #include <linux/kernel.h> 8 #include <linux/types.h> 9 #include <linux/bitops.h> 10 #include <linux/log2.h> 11 #include <time.h> 12 13 #include "../../util/cpumap.h" 14 #include "../../util/evsel.h" 15 #include "../../util/evlist.h" 16 #include "../../util/session.h" 17 #include "../../util/util.h" 18 #include "../../util/pmu.h" 19 #include "../../util/debug.h" 20 #include "../../util/auxtrace.h" 21 #include "../../util/arm-spe.h" 22 23 #define KiB(x) ((x) * 1024) 24 #define MiB(x) ((x) * 1024 * 1024) 25 26 struct arm_spe_recording { 27 struct auxtrace_record itr; 28 struct perf_pmu *arm_spe_pmu; 29 struct perf_evlist *evlist; 30 }; 31 32 static size_t 33 arm_spe_info_priv_size(struct auxtrace_record *itr __maybe_unused, 34 struct perf_evlist *evlist __maybe_unused) 35 { 36 return ARM_SPE_AUXTRACE_PRIV_SIZE; 37 } 38 39 static int arm_spe_info_fill(struct auxtrace_record *itr, 40 struct perf_session *session, 41 struct auxtrace_info_event *auxtrace_info, 42 size_t priv_size) 43 { 44 struct arm_spe_recording *sper = 45 container_of(itr, struct arm_spe_recording, itr); 46 struct perf_pmu *arm_spe_pmu = sper->arm_spe_pmu; 47 48 if (priv_size != ARM_SPE_AUXTRACE_PRIV_SIZE) 49 return -EINVAL; 50 51 if (!session->evlist->nr_mmaps) 52 return -EINVAL; 53 54 auxtrace_info->type = PERF_AUXTRACE_ARM_SPE; 55 auxtrace_info->priv[ARM_SPE_PMU_TYPE] = arm_spe_pmu->type; 56 57 return 0; 58 } 59 60 static int arm_spe_recording_options(struct auxtrace_record *itr, 61 struct perf_evlist *evlist, 62 struct record_opts *opts) 63 { 64 struct arm_spe_recording *sper = 65 container_of(itr, struct arm_spe_recording, itr); 66 struct perf_pmu *arm_spe_pmu = sper->arm_spe_pmu; 67 struct perf_evsel *evsel, *arm_spe_evsel = NULL; 68 bool privileged = geteuid() == 0 || perf_event_paranoid() < 0; 69 struct perf_evsel *tracking_evsel; 70 int err; 71 72 sper->evlist = evlist; 73 74 evlist__for_each_entry(evlist, evsel) { 75 if (evsel->attr.type == arm_spe_pmu->type) { 76 if (arm_spe_evsel) { 77 pr_err("There may be only one " ARM_SPE_PMU_NAME "x event\n"); 78 return -EINVAL; 79 } 80 evsel->attr.freq = 0; 81 evsel->attr.sample_period = 1; 82 arm_spe_evsel = evsel; 83 opts->full_auxtrace = true; 84 } 85 } 86 87 if (!opts->full_auxtrace) 88 return 0; 89 90 /* We are in full trace mode but '-m,xyz' wasn't specified */ 91 if (opts->full_auxtrace && !opts->auxtrace_mmap_pages) { 92 if (privileged) { 93 opts->auxtrace_mmap_pages = MiB(4) / page_size; 94 } else { 95 opts->auxtrace_mmap_pages = KiB(128) / page_size; 96 if (opts->mmap_pages == UINT_MAX) 97 opts->mmap_pages = KiB(256) / page_size; 98 } 99 } 100 101 /* Validate auxtrace_mmap_pages */ 102 if (opts->auxtrace_mmap_pages) { 103 size_t sz = opts->auxtrace_mmap_pages * (size_t)page_size; 104 size_t min_sz = KiB(8); 105 106 if (sz < min_sz || !is_power_of_2(sz)) { 107 pr_err("Invalid mmap size for ARM SPE: must be at least %zuKiB and a power of 2\n", 108 min_sz / 1024); 109 return -EINVAL; 110 } 111 } 112 113 114 /* 115 * To obtain the auxtrace buffer file descriptor, the auxtrace event 116 * must come first. 117 */ 118 perf_evlist__to_front(evlist, arm_spe_evsel); 119 120 perf_evsel__set_sample_bit(arm_spe_evsel, CPU); 121 perf_evsel__set_sample_bit(arm_spe_evsel, TIME); 122 perf_evsel__set_sample_bit(arm_spe_evsel, TID); 123 124 /* Add dummy event to keep tracking */ 125 err = parse_events(evlist, "dummy:u", NULL); 126 if (err) 127 return err; 128 129 tracking_evsel = perf_evlist__last(evlist); 130 perf_evlist__set_tracking_event(evlist, tracking_evsel); 131 132 tracking_evsel->attr.freq = 0; 133 tracking_evsel->attr.sample_period = 1; 134 perf_evsel__set_sample_bit(tracking_evsel, TIME); 135 perf_evsel__set_sample_bit(tracking_evsel, CPU); 136 perf_evsel__reset_sample_bit(tracking_evsel, BRANCH_STACK); 137 138 return 0; 139 } 140 141 static u64 arm_spe_reference(struct auxtrace_record *itr __maybe_unused) 142 { 143 struct timespec ts; 144 145 clock_gettime(CLOCK_MONOTONIC_RAW, &ts); 146 147 return ts.tv_sec ^ ts.tv_nsec; 148 } 149 150 static void arm_spe_recording_free(struct auxtrace_record *itr) 151 { 152 struct arm_spe_recording *sper = 153 container_of(itr, struct arm_spe_recording, itr); 154 155 free(sper); 156 } 157 158 static int arm_spe_read_finish(struct auxtrace_record *itr, int idx) 159 { 160 struct arm_spe_recording *sper = 161 container_of(itr, struct arm_spe_recording, itr); 162 struct perf_evsel *evsel; 163 164 evlist__for_each_entry(sper->evlist, evsel) { 165 if (evsel->attr.type == sper->arm_spe_pmu->type) 166 return perf_evlist__enable_event_idx(sper->evlist, 167 evsel, idx); 168 } 169 return -EINVAL; 170 } 171 172 struct auxtrace_record *arm_spe_recording_init(int *err, 173 struct perf_pmu *arm_spe_pmu) 174 { 175 struct arm_spe_recording *sper; 176 177 if (!arm_spe_pmu) { 178 *err = -ENODEV; 179 return NULL; 180 } 181 182 sper = zalloc(sizeof(struct arm_spe_recording)); 183 if (!sper) { 184 *err = -ENOMEM; 185 return NULL; 186 } 187 188 sper->arm_spe_pmu = arm_spe_pmu; 189 sper->itr.recording_options = arm_spe_recording_options; 190 sper->itr.info_priv_size = arm_spe_info_priv_size; 191 sper->itr.info_fill = arm_spe_info_fill; 192 sper->itr.free = arm_spe_recording_free; 193 sper->itr.reference = arm_spe_reference; 194 sper->itr.read_finish = arm_spe_read_finish; 195 sper->itr.alignment = 0; 196 197 return &sper->itr; 198 } 199 200 struct perf_event_attr 201 *arm_spe_pmu_default_config(struct perf_pmu *arm_spe_pmu) 202 { 203 struct perf_event_attr *attr; 204 205 attr = zalloc(sizeof(struct perf_event_attr)); 206 if (!attr) { 207 pr_err("arm_spe default config cannot allocate a perf_event_attr\n"); 208 return NULL; 209 } 210 211 /* 212 * If kernel driver doesn't advertise a minimum, 213 * use max allowable by PMSIDR_EL1.INTERVAL 214 */ 215 if (perf_pmu__scan_file(arm_spe_pmu, "caps/min_interval", "%llu", 216 &attr->sample_period) != 1) { 217 pr_debug("arm_spe driver doesn't advertise a min. interval. Using 4096\n"); 218 attr->sample_period = 4096; 219 } 220 221 arm_spe_pmu->selectable = true; 222 arm_spe_pmu->is_uncore = false; 223 224 return attr; 225 } 226