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 bool do_trace;
24 static GArray *sizes;
25
26 typedef struct {
27 uint64_t hits;
28 uint64_t last_hit;
29 uint64_t total_delta;
30 } MatchCount;
31
32 typedef struct {
33 char *match_string;
34 struct qemu_plugin_scoreboard *counts; /* MatchCount */
35 } Match;
36
37 static GArray *matches;
38
39 typedef struct {
40 Match *match;
41 uint64_t vaddr;
42 uint64_t hits;
43 char *disas;
44 } Instruction;
45
46 /* A hash table to hold matched instructions */
47 static GHashTable *match_insn_records;
48 static GMutex match_hash_lock;
49
50
get_insn_record(const char * disas,uint64_t vaddr,Match * m)51 static Instruction * get_insn_record(const char *disas, uint64_t vaddr, Match *m)
52 {
53 g_autofree char *str_hash = g_strdup_printf("%"PRIx64" %s", vaddr, disas);
54 Instruction *record;
55
56 g_mutex_lock(&match_hash_lock);
57
58 if (!match_insn_records) {
59 match_insn_records = g_hash_table_new(g_str_hash, g_str_equal);
60 }
61
62 record = g_hash_table_lookup(match_insn_records, str_hash);
63
64 if (!record) {
65 g_autoptr(GString) ts = g_string_new(str_hash);
66
67 record = g_new0(Instruction, 1);
68 record->disas = g_strdup(disas);
69 record->vaddr = vaddr;
70 record->match = m;
71
72 g_hash_table_insert(match_insn_records, str_hash, record);
73
74 g_string_prepend(ts, "Created record for: ");
75 g_string_append(ts, "\n");
76 qemu_plugin_outs(ts->str);
77 }
78
79 g_mutex_unlock(&match_hash_lock);
80
81 return record;
82 }
83
84 /*
85 * Initialise a new vcpu with reading the register list
86 */
vcpu_init(qemu_plugin_id_t id,unsigned int vcpu_index)87 static void vcpu_init(qemu_plugin_id_t id, unsigned int vcpu_index)
88 {
89 g_autoptr(GArray) reg_list = qemu_plugin_get_registers();
90 g_autoptr(GByteArray) reg_value = g_byte_array_new();
91
92 if (reg_list) {
93 for (int i = 0; i < reg_list->len; i++) {
94 qemu_plugin_reg_descriptor *rd = &g_array_index(
95 reg_list, qemu_plugin_reg_descriptor, i);
96 int count = qemu_plugin_read_register(rd->handle, reg_value);
97 g_assert(count > 0);
98 }
99 }
100 }
101
102
vcpu_insn_exec_before(unsigned int cpu_index,void * udata)103 static void vcpu_insn_exec_before(unsigned int cpu_index, void *udata)
104 {
105 qemu_plugin_u64_add(insn_count, cpu_index, 1);
106 }
107
vcpu_insn_matched_exec_before(unsigned int cpu_index,void * udata)108 static void vcpu_insn_matched_exec_before(unsigned int cpu_index, void *udata)
109 {
110 Instruction *insn = (Instruction *) udata;
111 Match *insn_match = insn->match;
112 MatchCount *match = qemu_plugin_scoreboard_find(insn_match->counts,
113 cpu_index);
114
115 insn->hits++;
116
117 uint64_t icount = qemu_plugin_u64_get(insn_count, cpu_index);
118 uint64_t delta = icount - match->last_hit;
119
120 match->hits++;
121 match->total_delta += delta;
122 match->last_hit = icount;
123
124 if (do_trace) {
125 g_autoptr(GString) ts = g_string_new("");
126 g_string_append_printf(ts, "0x%" PRIx64 ", '%s', %"PRId64 " hits",
127 insn->vaddr, insn->disas, insn->hits);
128 g_string_append_printf(ts,
129 " , cpu %u,"
130 " %"PRId64" match hits,"
131 " Δ+%"PRId64 " since last match,"
132 " %"PRId64 " avg insns/match\n",
133 cpu_index,
134 match->hits, delta,
135 match->total_delta / match->hits);
136
137 qemu_plugin_outs(ts->str);
138 }
139 }
140
vcpu_tb_trans(qemu_plugin_id_t id,struct qemu_plugin_tb * tb)141 static void vcpu_tb_trans(qemu_plugin_id_t id, struct qemu_plugin_tb *tb)
142 {
143 size_t n = qemu_plugin_tb_n_insns(tb);
144 size_t i;
145
146 for (i = 0; i < n; i++) {
147 struct qemu_plugin_insn *insn = qemu_plugin_tb_get_insn(tb, i);
148
149 if (do_inline) {
150 qemu_plugin_register_vcpu_insn_exec_inline_per_vcpu(
151 insn, QEMU_PLUGIN_INLINE_ADD_U64, insn_count, 1);
152 } else {
153 qemu_plugin_register_vcpu_insn_exec_cb(
154 insn, vcpu_insn_exec_before, QEMU_PLUGIN_CB_NO_REGS, NULL);
155 }
156
157 if (do_size) {
158 size_t sz = qemu_plugin_insn_size(insn);
159 if (sz > sizes->len) {
160 g_array_set_size(sizes, sz);
161 }
162 unsigned long *cnt = &g_array_index(sizes, unsigned long, sz);
163 (*cnt)++;
164 }
165
166 /*
167 * If we are tracking certain instructions we will need more
168 * information about the instruction which we also need to
169 * save if there is a hit.
170 *
171 * We only want one record for each occurrence of the matched
172 * instruction.
173 */
174 if (matches->len) {
175 char *insn_disas = qemu_plugin_insn_disas(insn);
176 for (int j = 0; j < matches->len; j++) {
177 Match *m = &g_array_index(matches, Match, j);
178 if (g_str_has_prefix(insn_disas, m->match_string)) {
179 Instruction *rec = get_insn_record(insn_disas,
180 qemu_plugin_insn_vaddr(insn),
181 m);
182
183 qemu_plugin_register_vcpu_insn_exec_cb(
184 insn, vcpu_insn_matched_exec_before,
185 QEMU_PLUGIN_CB_NO_REGS, rec);
186 }
187 }
188 g_free(insn_disas);
189 }
190 }
191 }
192
plugin_exit(qemu_plugin_id_t id,void * p)193 static void plugin_exit(qemu_plugin_id_t id, void *p)
194 {
195 g_autoptr(GString) out = g_string_new(NULL);
196 int i;
197
198 if (do_size) {
199 for (i = 0; i <= sizes->len; i++) {
200 unsigned long *cnt = &g_array_index(sizes, unsigned long, i);
201 if (*cnt) {
202 g_string_append_printf(out,
203 "len %d bytes: %ld insns\n", i, *cnt);
204 }
205 }
206 } else {
207 for (i = 0; i < qemu_plugin_num_vcpus(); i++) {
208 g_string_append_printf(out, "cpu %d insns: %" PRIu64 "\n",
209 i, qemu_plugin_u64_get(insn_count, i));
210 }
211 g_string_append_printf(out, "total insns: %" PRIu64 "\n",
212 qemu_plugin_u64_sum(insn_count));
213 }
214 qemu_plugin_outs(out->str);
215 qemu_plugin_scoreboard_free(insn_count.score);
216
217 g_mutex_lock(&match_hash_lock);
218
219 for (i = 0; i < matches->len; ++i) {
220 Match *m = &g_array_index(matches, Match, i);
221 GHashTableIter iter;
222 Instruction *record;
223 qemu_plugin_u64 hit_e = qemu_plugin_scoreboard_u64_in_struct(m->counts, MatchCount, hits);
224 uint64_t hits = qemu_plugin_u64_sum(hit_e);
225
226 g_string_printf(out, "Match: %s, hits %"PRId64"\n", m->match_string, hits);
227 qemu_plugin_outs(out->str);
228
229 g_hash_table_iter_init(&iter, match_insn_records);
230 while (g_hash_table_iter_next(&iter, NULL, (void **)&record)) {
231 if (record->match == m) {
232 g_string_printf(out,
233 " %"PRIx64": %s (hits %"PRId64")\n",
234 record->vaddr,
235 record->disas,
236 record->hits);
237 qemu_plugin_outs(out->str);
238 }
239 }
240
241 g_free(m->match_string);
242 qemu_plugin_scoreboard_free(m->counts);
243 }
244
245 g_mutex_unlock(&match_hash_lock);
246
247 g_array_free(matches, TRUE);
248 g_array_free(sizes, TRUE);
249 }
250
251
252 /* Add a match to the array of matches */
parse_match(char * match)253 static void parse_match(char *match)
254 {
255 Match new_match = {
256 .match_string = g_strdup(match),
257 .counts = qemu_plugin_scoreboard_new(sizeof(MatchCount)) };
258 g_array_append_val(matches, new_match);
259 }
260
qemu_plugin_install(qemu_plugin_id_t id,const qemu_info_t * info,int argc,char ** argv)261 QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id,
262 const qemu_info_t *info,
263 int argc, char **argv)
264 {
265 matches = g_array_new(false, true, sizeof(Match));
266 /* null terminated so 0 is not a special case */
267 sizes = g_array_new(true, true, sizeof(unsigned long));
268
269 for (int i = 0; i < argc; i++) {
270 char *opt = argv[i];
271 g_auto(GStrv) tokens = g_strsplit(opt, "=", 2);
272 if (g_strcmp0(tokens[0], "inline") == 0) {
273 if (!qemu_plugin_bool_parse(tokens[0], tokens[1], &do_inline)) {
274 fprintf(stderr, "boolean argument parsing failed: %s\n", opt);
275 return -1;
276 }
277 } else if (g_strcmp0(tokens[0], "sizes") == 0) {
278 if (!qemu_plugin_bool_parse(tokens[0], tokens[1], &do_size)) {
279 fprintf(stderr, "boolean argument parsing failed: %s\n", opt);
280 return -1;
281 }
282 } else if (g_strcmp0(tokens[0], "match") == 0) {
283 parse_match(tokens[1]);
284 } else if (g_strcmp0(tokens[0], "trace") == 0) {
285 if (!qemu_plugin_bool_parse(tokens[0], tokens[1], &do_trace)) {
286 fprintf(stderr, "boolean argument parsing failed: %s\n", opt);
287 return -1;
288 }
289 } else {
290 fprintf(stderr, "option parsing failed: %s\n", opt);
291 return -1;
292 }
293 }
294
295 insn_count = qemu_plugin_scoreboard_u64(
296 qemu_plugin_scoreboard_new(sizeof(uint64_t)));
297
298 /* Register init, translation block and exit callbacks */
299 qemu_plugin_register_vcpu_init_cb(id, vcpu_init);
300 qemu_plugin_register_vcpu_tb_trans_cb(id, vcpu_tb_trans);
301 qemu_plugin_register_atexit_cb(id, plugin_exit, NULL);
302 return 0;
303 }
304