1 /* 2 * Copyright (C) 2018, Emilio G. Cota <cota@braap.org> 3 * 4 * License: GNU GPL, version 2 or later. 5 * See the COPYING file in the top-level directory. 6 */ 7 #include <inttypes.h> 8 #include <assert.h> 9 #include <stdlib.h> 10 #include <string.h> 11 #include <unistd.h> 12 #include <stdio.h> 13 #include <glib.h> 14 15 #include <qemu-plugin.h> 16 17 QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION; 18 19 #define MAX_CPUS 8 /* lets not go nuts */ 20 21 typedef struct { 22 uint64_t last_pc; 23 uint64_t insn_count; 24 } InstructionCount; 25 26 static InstructionCount counts[MAX_CPUS]; 27 static uint64_t inline_insn_count; 28 29 static bool do_inline; 30 static bool do_size; 31 static GArray *sizes; 32 33 typedef struct { 34 char *match_string; 35 uint64_t hits[MAX_CPUS]; 36 uint64_t last_hit[MAX_CPUS]; 37 uint64_t total_delta[MAX_CPUS]; 38 GPtrArray *history[MAX_CPUS]; 39 } Match; 40 41 static GArray *matches; 42 43 typedef struct { 44 Match *match; 45 uint64_t vaddr; 46 uint64_t hits; 47 char *disas; 48 } Instruction; 49 50 static void vcpu_insn_exec_before(unsigned int cpu_index, void *udata) 51 { 52 unsigned int i = cpu_index % MAX_CPUS; 53 InstructionCount *c = &counts[i]; 54 uint64_t this_pc = GPOINTER_TO_UINT(udata); 55 if (this_pc == c->last_pc) { 56 g_autofree gchar *out = g_strdup_printf("detected repeat execution @ 0x%" 57 PRIx64 "\n", this_pc); 58 qemu_plugin_outs(out); 59 } 60 c->last_pc = this_pc; 61 c->insn_count++; 62 } 63 64 static void vcpu_insn_matched_exec_before(unsigned int cpu_index, void *udata) 65 { 66 unsigned int i = cpu_index % MAX_CPUS; 67 Instruction *insn = (Instruction *) udata; 68 Match *match = insn->match; 69 g_autoptr(GString) ts = g_string_new(""); 70 71 insn->hits++; 72 g_string_append_printf(ts, "0x%" PRIx64 ", '%s', %"PRId64 " hits", 73 insn->vaddr, insn->disas, insn->hits); 74 75 uint64_t icount = counts[i].insn_count; 76 uint64_t delta = icount - match->last_hit[i]; 77 78 match->hits[i]++; 79 match->total_delta[i] += delta; 80 81 g_string_append_printf(ts, 82 ", %"PRId64" match hits, " 83 "Δ+%"PRId64 " since last match," 84 " %"PRId64 " avg insns/match\n", 85 match->hits[i], delta, 86 match->total_delta[i] / match->hits[i]); 87 88 match->last_hit[i] = icount; 89 90 qemu_plugin_outs(ts->str); 91 92 g_ptr_array_add(match->history[i], insn); 93 } 94 95 static void vcpu_tb_trans(qemu_plugin_id_t id, struct qemu_plugin_tb *tb) 96 { 97 size_t n = qemu_plugin_tb_n_insns(tb); 98 size_t i; 99 100 for (i = 0; i < n; i++) { 101 struct qemu_plugin_insn *insn = qemu_plugin_tb_get_insn(tb, i); 102 103 if (do_inline) { 104 qemu_plugin_register_vcpu_insn_exec_inline( 105 insn, QEMU_PLUGIN_INLINE_ADD_U64, &inline_insn_count, 1); 106 } else { 107 uint64_t vaddr = qemu_plugin_insn_vaddr(insn); 108 qemu_plugin_register_vcpu_insn_exec_cb( 109 insn, vcpu_insn_exec_before, QEMU_PLUGIN_CB_NO_REGS, 110 GUINT_TO_POINTER(vaddr)); 111 } 112 113 if (do_size) { 114 size_t sz = qemu_plugin_insn_size(insn); 115 if (sz > sizes->len) { 116 g_array_set_size(sizes, sz); 117 } 118 unsigned long *cnt = &g_array_index(sizes, unsigned long, sz); 119 (*cnt)++; 120 } 121 122 /* 123 * If we are tracking certain instructions we will need more 124 * information about the instruction which we also need to 125 * save if there is a hit. 126 */ 127 if (matches) { 128 char *insn_disas = qemu_plugin_insn_disas(insn); 129 int j; 130 for (j = 0; j < matches->len; j++) { 131 Match *m = &g_array_index(matches, Match, j); 132 if (g_str_has_prefix(insn_disas, m->match_string)) { 133 Instruction *rec = g_new0(Instruction, 1); 134 rec->disas = g_strdup(insn_disas); 135 rec->vaddr = qemu_plugin_insn_vaddr(insn); 136 rec->match = m; 137 qemu_plugin_register_vcpu_insn_exec_cb( 138 insn, vcpu_insn_matched_exec_before, 139 QEMU_PLUGIN_CB_NO_REGS, rec); 140 } 141 } 142 g_free(insn_disas); 143 } 144 } 145 } 146 147 static void plugin_exit(qemu_plugin_id_t id, void *p) 148 { 149 g_autoptr(GString) out = g_string_new(NULL); 150 int i; 151 152 if (do_size) { 153 for (i = 0; i <= sizes->len; i++) { 154 unsigned long *cnt = &g_array_index(sizes, unsigned long, i); 155 if (*cnt) { 156 g_string_append_printf(out, 157 "len %d bytes: %ld insns\n", i, *cnt); 158 } 159 } 160 } else if (do_inline) { 161 g_string_append_printf(out, "insns: %" PRIu64 "\n", inline_insn_count); 162 } else { 163 uint64_t total_insns = 0; 164 for (i = 0; i < MAX_CPUS; i++) { 165 InstructionCount *c = &counts[i]; 166 if (c->insn_count) { 167 g_string_append_printf(out, "cpu %d insns: %" PRIu64 "\n", 168 i, c->insn_count); 169 total_insns += c->insn_count; 170 } 171 } 172 g_string_append_printf(out, "total insns: %" PRIu64 "\n", 173 total_insns); 174 } 175 qemu_plugin_outs(out->str); 176 } 177 178 179 /* Add a match to the array of matches */ 180 static void parse_match(char *match) 181 { 182 Match new_match = { .match_string = match }; 183 int i; 184 for (i = 0; i < MAX_CPUS; i++) { 185 new_match.history[i] = g_ptr_array_new(); 186 } 187 if (!matches) { 188 matches = g_array_new(false, true, sizeof(Match)); 189 } 190 g_array_append_val(matches, new_match); 191 } 192 193 QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id, 194 const qemu_info_t *info, 195 int argc, char **argv) 196 { 197 for (int i = 0; i < argc; i++) { 198 char *opt = argv[i]; 199 g_autofree char **tokens = g_strsplit(opt, "=", 2); 200 if (g_strcmp0(tokens[0], "inline") == 0) { 201 if (!qemu_plugin_bool_parse(tokens[0], tokens[1], &do_inline)) { 202 fprintf(stderr, "boolean argument parsing failed: %s\n", opt); 203 return -1; 204 } 205 } else if (g_strcmp0(tokens[0], "sizes") == 0) { 206 if (!qemu_plugin_bool_parse(tokens[0], tokens[1], &do_size)) { 207 fprintf(stderr, "boolean argument parsing failed: %s\n", opt); 208 return -1; 209 } 210 } else if (g_strcmp0(tokens[0], "match") == 0) { 211 parse_match(tokens[1]); 212 } else { 213 fprintf(stderr, "option parsing failed: %s\n", opt); 214 return -1; 215 } 216 } 217 218 if (do_size) { 219 sizes = g_array_new(true, true, sizeof(unsigned long)); 220 } 221 222 qemu_plugin_register_vcpu_tb_trans_cb(id, vcpu_tb_trans); 223 qemu_plugin_register_atexit_cb(id, plugin_exit, NULL); 224 return 0; 225 } 226