tests/plugin/insn.c

   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 static qemu_plugin_u64 insn_count;
  20
  21 static bool do_inline;
  22 static bool do_size;
  23 static GArray *sizes;
  24
  25 typedef struct {
  26     uint64_t hits;
  27     uint64_t last_hit;
  28     uint64_t total_delta;
  29 } MatchCount;
  30
  31 typedef struct {
  32     char *match_string;
  33     struct qemu_plugin_scoreboard *counts; /* MatchCount */
  34 } Match;
  35
  36 static GArray *matches;
  37
  38 typedef struct {
  39     Match *match;
  40     uint64_t vaddr;
  41     uint64_t hits;
  42     char *disas;
  43 } Instruction;
  44
  45 /*
  46  * Initialise a new vcpu with reading the register list
  47  */
  48 static void vcpu_init(qemu_plugin_id_t id, unsigned int vcpu_index)
  49 {
  50     g_autoptr(GArray) reg_list = qemu_plugin_get_registers();
  51     g_autoptr(GByteArray) reg_value = g_byte_array_new();
  52
  53     if (reg_list) {
  54         for (int i = 0; i < reg_list->len; i++) {
  55             qemu_plugin_reg_descriptor *rd = &g_array_index(
  56                 reg_list, qemu_plugin_reg_descriptor, i);
  57             int count = qemu_plugin_read_register(rd->handle, reg_value);
  58             g_assert(count > 0);
  59         }
  60     }
  61 }
  62
  63
  64 static void vcpu_insn_exec_before(unsigned int cpu_index, void *udata)
  65 {
  66     qemu_plugin_u64_add(insn_count, cpu_index, 1);
  67 }
  68
  69 static void vcpu_insn_matched_exec_before(unsigned int cpu_index, void *udata)
  70 {
  71     Instruction *insn = (Instruction *) udata;
  72     Match *insn_match = insn->match;
  73     MatchCount *match = qemu_plugin_scoreboard_find(insn_match->counts,
  74                                                     cpu_index);
  75
  76     g_autoptr(GString) ts = g_string_new("");
  77
  78     insn->hits++;
  79     g_string_append_printf(ts, "0x%" PRIx64 ", '%s', %"PRId64 " hits",
  80                            insn->vaddr, insn->disas, insn->hits);
  81
  82     uint64_t icount = qemu_plugin_u64_get(insn_count, cpu_index);
  83     uint64_t delta = icount - match->last_hit;
  84
  85     match->hits++;
  86     match->total_delta += delta;
  87
  88     g_string_append_printf(ts,
  89                            " , cpu %u,"
  90                            " %"PRId64" match hits,"
  91                            " Δ+%"PRId64 " since last match,"
  92                            " %"PRId64 " avg insns/match\n",
  93                            cpu_index,
  94                            match->hits, delta,
  95                            match->total_delta / match->hits);
  96
  97     match->last_hit = icount;
  98
  99     qemu_plugin_outs(ts->str);
 100 }
 101
 102 static void vcpu_tb_trans(qemu_plugin_id_t id, struct qemu_plugin_tb *tb)
 103 {
 104     size_t n = qemu_plugin_tb_n_insns(tb);
 105     size_t i;
 106
 107     for (i = 0; i < n; i++) {
 108         struct qemu_plugin_insn *insn = qemu_plugin_tb_get_insn(tb, i);
 109
 110         if (do_inline) {
 111             qemu_plugin_register_vcpu_insn_exec_inline_per_vcpu(
 112                 insn, QEMU_PLUGIN_INLINE_ADD_U64, insn_count, 1);
 113         } else {
 114             uint64_t vaddr = qemu_plugin_insn_vaddr(insn);
 115             qemu_plugin_register_vcpu_insn_exec_cb(
 116                 insn, vcpu_insn_exec_before, QEMU_PLUGIN_CB_NO_REGS,
 117                 GUINT_TO_POINTER(vaddr));
 118         }
 119
 120         if (do_size) {
 121             size_t sz = qemu_plugin_insn_size(insn);
 122             if (sz > sizes->len) {
 123                 g_array_set_size(sizes, sz);
 124             }
 125             unsigned long *cnt = &g_array_index(sizes, unsigned long, sz);
 126             (*cnt)++;
 127         }
 128
 129         /*
 130          * If we are tracking certain instructions we will need more
 131          * information about the instruction which we also need to
 132          * save if there is a hit.
 133          */
 134         if (matches->len) {
 135             char *insn_disas = qemu_plugin_insn_disas(insn);
 136             for (int j = 0; j < matches->len; j++) {
 137                 Match *m = &g_array_index(matches, Match, j);
 138                 if (g_str_has_prefix(insn_disas, m->match_string)) {
 139                     Instruction *rec = g_new0(Instruction, 1);
 140                     rec->disas = g_strdup(insn_disas);
 141                     rec->vaddr = qemu_plugin_insn_vaddr(insn);
 142                     rec->match = m;
 143                     qemu_plugin_register_vcpu_insn_exec_cb(
 144                         insn, vcpu_insn_matched_exec_before,
 145                         QEMU_PLUGIN_CB_NO_REGS, rec);
 146                 }
 147             }
 148             g_free(insn_disas);
 149         }
 150     }
 151 }
 152
 153 static void plugin_exit(qemu_plugin_id_t id, void *p)
 154 {
 155     g_autoptr(GString) out = g_string_new(NULL);
 156     int i;
 157
 158     if (do_size) {
 159         for (i = 0; i <= sizes->len; i++) {
 160             unsigned long *cnt = &g_array_index(sizes, unsigned long, i);
 161             if (*cnt) {
 162                 g_string_append_printf(out,
 163                                        "len %d bytes: %ld insns\n", i, *cnt);
 164             }
 165         }
 166     } else {
 167         for (i = 0; i < qemu_plugin_num_vcpus(); i++) {
 168             g_string_append_printf(out, "cpu %d insns: %" PRIu64 "\n",
 169                                    i, qemu_plugin_u64_get(insn_count, i));
 170         }
 171         g_string_append_printf(out, "total insns: %" PRIu64 "\n",
 172                                qemu_plugin_u64_sum(insn_count));
 173     }
 174     qemu_plugin_outs(out->str);
 175
 176     qemu_plugin_scoreboard_free(insn_count.score);
 177     for (i = 0; i < matches->len; ++i) {
 178         Match *m = &g_array_index(matches, Match, i);
 179         g_free(m->match_string);
 180         qemu_plugin_scoreboard_free(m->counts);
 181     }
 182     g_array_free(matches, TRUE);
 183     g_array_free(sizes, TRUE);
 184 }
 185
 186
 187 /* Add a match to the array of matches */
 188 static void parse_match(char *match)
 189 {
 190     Match new_match = {
 191         .match_string = g_strdup(match),
 192         .counts = qemu_plugin_scoreboard_new(sizeof(MatchCount)) };
 193     g_array_append_val(matches, new_match);
 194 }
 195
 196 QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id,
 197                                            const qemu_info_t *info,
 198                                            int argc, char **argv)
 199 {
 200     matches = g_array_new(false, true, sizeof(Match));
 201     /* null terminated so 0 is not a special case */
 202     sizes = g_array_new(true, true, sizeof(unsigned long));
 203
 204     for (int i = 0; i < argc; i++) {
 205         char *opt = argv[i];
 206         g_auto(GStrv) tokens = g_strsplit(opt, "=", 2);
 207         if (g_strcmp0(tokens[0], "inline") == 0) {
 208             if (!qemu_plugin_bool_parse(tokens[0], tokens[1], &do_inline)) {
 209                 fprintf(stderr, "boolean argument parsing failed: %s\n", opt);
 210                 return -1;
 211             }
 212         } else if (g_strcmp0(tokens[0], "sizes") == 0) {
 213             if (!qemu_plugin_bool_parse(tokens[0], tokens[1], &do_size)) {
 214                 fprintf(stderr, "boolean argument parsing failed: %s\n", opt);
 215                 return -1;
 216             }
 217         } else if (g_strcmp0(tokens[0], "match") == 0) {
 218             parse_match(tokens[1]);
 219         } else {
 220             fprintf(stderr, "option parsing failed: %s\n", opt);
 221             return -1;
 222         }
 223     }
 224
 225     insn_count = qemu_plugin_scoreboard_u64(
 226         qemu_plugin_scoreboard_new(sizeof(uint64_t)));
 227
 228     /* Register init, translation block and exit callbacks */
 229     qemu_plugin_register_vcpu_init_cb(id, vcpu_init);
 230     qemu_plugin_register_vcpu_tb_trans_cb(id, vcpu_tb_trans);
 231     qemu_plugin_register_atexit_cb(id, plugin_exit, NULL);
 232     return 0;
 233 }