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