Loading...
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 | // SPDX-License-Identifier: GPL-2.0+ /* * Copyright 2018 IBM Corporation. */ #define __SANE_USERSPACE_TYPES__ #include <sys/types.h> #include <stdint.h> #include <malloc.h> #include <unistd.h> #include <stdlib.h> #include <string.h> #include <stdio.h> #include "utils.h" #include "flush_utils.h" int rfi_flush_test(void) { char *p; int repetitions = 10; int fd, passes = 0, iter, rc = 0; struct perf_event_read v; __u64 l1d_misses_total = 0; unsigned long iterations = 100000, zero_size = 24 * 1024; unsigned long l1d_misses_expected; int rfi_flush_orig, rfi_flush; int have_entry_flush, entry_flush_orig; SKIP_IF(geteuid() != 0); // The PMU event we use only works on Power7 or later SKIP_IF(!have_hwcap(PPC_FEATURE_ARCH_2_06)); if (read_debugfs_int("powerpc/rfi_flush", &rfi_flush_orig) < 0) { perror("Unable to read powerpc/rfi_flush debugfs file"); SKIP_IF(1); } if (read_debugfs_int("powerpc/entry_flush", &entry_flush_orig) < 0) { have_entry_flush = 0; } else { have_entry_flush = 1; if (entry_flush_orig != 0) { if (write_debugfs_int("powerpc/entry_flush", 0) < 0) { perror("error writing to powerpc/entry_flush debugfs file"); return 1; } } } rfi_flush = rfi_flush_orig; fd = perf_event_open_counter(PERF_TYPE_HW_CACHE, PERF_L1D_READ_MISS_CONFIG, -1); FAIL_IF(fd < 0); p = (char *)memalign(zero_size, CACHELINE_SIZE); FAIL_IF(perf_event_enable(fd)); // disable L1 prefetching set_dscr(1); iter = repetitions; /* * We expect to see l1d miss for each cacheline access when rfi_flush * is set. Allow a small variation on this. */ l1d_misses_expected = iterations * (zero_size / CACHELINE_SIZE - 2); again: FAIL_IF(perf_event_reset(fd)); syscall_loop(p, iterations, zero_size); FAIL_IF(read(fd, &v, sizeof(v)) != sizeof(v)); if (rfi_flush && v.l1d_misses >= l1d_misses_expected) passes++; else if (!rfi_flush && v.l1d_misses < (l1d_misses_expected / 2)) passes++; l1d_misses_total += v.l1d_misses; while (--iter) goto again; if (passes < repetitions) { printf("FAIL (L1D misses with rfi_flush=%d: %llu %c %lu) [%d/%d failures]\n", rfi_flush, l1d_misses_total, rfi_flush ? '<' : '>', rfi_flush ? repetitions * l1d_misses_expected : repetitions * l1d_misses_expected / 2, repetitions - passes, repetitions); rc = 1; } else printf("PASS (L1D misses with rfi_flush=%d: %llu %c %lu) [%d/%d pass]\n", rfi_flush, l1d_misses_total, rfi_flush ? '>' : '<', rfi_flush ? repetitions * l1d_misses_expected : repetitions * l1d_misses_expected / 2, passes, repetitions); if (rfi_flush == rfi_flush_orig) { rfi_flush = !rfi_flush_orig; if (write_debugfs_int("powerpc/rfi_flush", rfi_flush) < 0) { perror("error writing to powerpc/rfi_flush debugfs file"); return 1; } iter = repetitions; l1d_misses_total = 0; passes = 0; goto again; } perf_event_disable(fd); close(fd); set_dscr(0); if (write_debugfs_int("powerpc/rfi_flush", rfi_flush_orig) < 0) { perror("unable to restore original value of powerpc/rfi_flush debugfs file"); return 1; } if (have_entry_flush) { if (write_debugfs_int("powerpc/entry_flush", entry_flush_orig) < 0) { perror("unable to restore original value of powerpc/entry_flush " "debugfs file"); return 1; } } return rc; } int main(int argc, char *argv[]) { return test_harness(rfi_flush_test, "rfi_flush_test"); } |