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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 | // SPDX-License-Identifier: GPL-2.0 /* * perf.c - performance monitor * * Copyright (C) 2021 Intel Corporation * * Author: Lu Baolu <baolu.lu@linux.intel.com> * Fenghua Yu <fenghua.yu@intel.com> */ #include <linux/spinlock.h> #include "iommu.h" #include "perf.h" static DEFINE_SPINLOCK(latency_lock); bool dmar_latency_enabled(struct intel_iommu *iommu, enum latency_type type) { struct latency_statistic *lstat = iommu->perf_statistic; return lstat && lstat[type].enabled; } int dmar_latency_enable(struct intel_iommu *iommu, enum latency_type type) { struct latency_statistic *lstat; unsigned long flags; int ret = -EBUSY; if (dmar_latency_enabled(iommu, type)) return 0; spin_lock_irqsave(&latency_lock, flags); if (!iommu->perf_statistic) { iommu->perf_statistic = kzalloc(sizeof(*lstat) * DMAR_LATENCY_NUM, GFP_ATOMIC); if (!iommu->perf_statistic) { ret = -ENOMEM; goto unlock_out; } } lstat = iommu->perf_statistic; if (!lstat[type].enabled) { lstat[type].enabled = true; lstat[type].counter[COUNTS_MIN] = UINT_MAX; ret = 0; } unlock_out: spin_unlock_irqrestore(&latency_lock, flags); return ret; } void dmar_latency_disable(struct intel_iommu *iommu, enum latency_type type) { struct latency_statistic *lstat = iommu->perf_statistic; unsigned long flags; if (!dmar_latency_enabled(iommu, type)) return; spin_lock_irqsave(&latency_lock, flags); memset(&lstat[type], 0, sizeof(*lstat) * DMAR_LATENCY_NUM); spin_unlock_irqrestore(&latency_lock, flags); } void dmar_latency_update(struct intel_iommu *iommu, enum latency_type type, u64 latency) { struct latency_statistic *lstat = iommu->perf_statistic; unsigned long flags; u64 min, max; if (!dmar_latency_enabled(iommu, type)) return; spin_lock_irqsave(&latency_lock, flags); if (latency < 100) lstat[type].counter[COUNTS_10e2]++; else if (latency < 1000) lstat[type].counter[COUNTS_10e3]++; else if (latency < 10000) lstat[type].counter[COUNTS_10e4]++; else if (latency < 100000) lstat[type].counter[COUNTS_10e5]++; else if (latency < 1000000) lstat[type].counter[COUNTS_10e6]++; else if (latency < 10000000) lstat[type].counter[COUNTS_10e7]++; else lstat[type].counter[COUNTS_10e8_plus]++; min = lstat[type].counter[COUNTS_MIN]; max = lstat[type].counter[COUNTS_MAX]; lstat[type].counter[COUNTS_MIN] = min_t(u64, min, latency); lstat[type].counter[COUNTS_MAX] = max_t(u64, max, latency); lstat[type].counter[COUNTS_SUM] += latency; lstat[type].samples++; spin_unlock_irqrestore(&latency_lock, flags); } static char *latency_counter_names[] = { " <0.1us", " 0.1us-1us", " 1us-10us", " 10us-100us", " 100us-1ms", " 1ms-10ms", " >=10ms", " min(us)", " max(us)", " average(us)" }; static char *latency_type_names[] = { " inv_iotlb", " inv_devtlb", " inv_iec", " svm_prq" }; int dmar_latency_snapshot(struct intel_iommu *iommu, char *str, size_t size) { struct latency_statistic *lstat = iommu->perf_statistic; unsigned long flags; int bytes = 0, i, j; memset(str, 0, size); for (i = 0; i < COUNTS_NUM; i++) bytes += snprintf(str + bytes, size - bytes, "%s", latency_counter_names[i]); spin_lock_irqsave(&latency_lock, flags); for (i = 0; i < DMAR_LATENCY_NUM; i++) { if (!dmar_latency_enabled(iommu, i)) continue; bytes += snprintf(str + bytes, size - bytes, "\n%s", latency_type_names[i]); for (j = 0; j < COUNTS_NUM; j++) { u64 val = lstat[i].counter[j]; switch (j) { case COUNTS_MIN: if (val == UINT_MAX) val = 0; else val = div_u64(val, 1000); break; case COUNTS_MAX: val = div_u64(val, 1000); break; case COUNTS_SUM: if (lstat[i].samples) val = div_u64(val, (lstat[i].samples * 1000)); else val = 0; break; default: break; } bytes += snprintf(str + bytes, size - bytes, "%12lld", val); } } spin_unlock_irqrestore(&latency_lock, flags); return bytes; } |