@@ -679,6 +679,170 @@ void dump_tb_info(int id, int log_mask, bool use_monitor)
/* tbdi free'd by do_dump_tb_info_safe */
}
+/* TB CFG xdot/dot dump implementation */
+#define MAX_CFG_NUM_NODES 1000
+static int cfg_tb_id;
+static GHashTable *cfg_nodes;
+static uint64_t root_count;
+
+static void fputs_jump(TBStatistics *from, TBStatistics *to, FILE *dot)
+{
+ if (!from || !to) {
+ return;
+ }
+
+ int *from_id = (int *) g_hash_table_lookup(cfg_nodes, from);
+ int *to_id = (int *) g_hash_table_lookup(cfg_nodes, to);
+
+ if (!from_id || !to_id) {
+ return;
+ }
+
+ fprintf(dot, " node_%d -> node_%d;\n", *from_id, *to_id);
+}
+
+/* Hotness colors used in the CFG */
+#define HOT_RED1 0xFF000 /* RGB(255,0,0) */
+#define HOT_RED2 0xFF333 /* RGB(255,51,48) */
+#define MILD_RED 0xFF666 /* RGB(255,102,96) */
+#define WEAK_RED1 0xFF999 /* RGB(255,153,144) */
+#define WEAK_RED2 0xFFCCC /* RGB(255,204,192) */
+
+static void fputs_tbstats(TBStatistics *tbs, FILE *dot, int log_flags)
+{
+ if (!tbs) {
+ return;
+ }
+
+ uint32_t color = MILD_RED;
+ uint64_t count = tbs->executions.normal;
+ if (count > 1.6 * root_count) {
+ color = HOT_RED1;
+ } else if (count > 1.2 * root_count) {
+ color = HOT_RED2;
+ } else if (count < 0.4 * root_count) {
+ color = WEAK_RED2;
+ } else if (count < 0.8 * root_count) {
+ color = WEAK_RED1;
+ }
+
+ GString *code_s = get_code_string(tbs, log_flags);
+
+ for (int i = 0; i < code_s->len; i++) {
+ if (code_s->str[i] == '\n') {
+ code_s->str[i] = ' ';
+ code_s = g_string_insert(code_s, i, "\\l");
+ i += 2;
+ }
+ }
+
+ fprintf(dot,
+ " node_%d [fillcolor=\"#%xFF0000\" shape=\"record\" "
+ "label=\"TB %d\\l"
+ "-------------\\l"
+ "PC:\t0x"TARGET_FMT_lx"\\l"
+ "exec count:\t%lu\\l"
+ "\\l %s\"];\n",
+ cfg_tb_id, color, cfg_tb_id, tbs->pc,
+ tbs->executions.normal, code_s->str);
+
+ int *id = g_new(int, 1);
+ *id = cfg_tb_id;
+ g_hash_table_insert(cfg_nodes, tbs, id);
+
+ cfg_tb_id++;
+
+ g_string_free(code_s, true);
+}
+
+static void fputs_preorder_walk(TBStatistics *tbs, int depth, FILE *dot, int log_flags)
+{
+ if (tbs && depth > 0
+ && cfg_tb_id < MAX_CFG_NUM_NODES
+ && !g_hash_table_contains(cfg_nodes, tbs)) {
+
+ fputs_tbstats(tbs, dot, log_flags);
+
+ if (tbs->tb) {
+ TranslationBlock *left_tb = NULL;
+ TranslationBlock *right_tb = NULL;
+ if (tbs->tb->jmp_dest[0]) {
+ left_tb = (TranslationBlock *) atomic_read(tbs->tb->jmp_dest);
+ }
+ if (tbs->tb->jmp_dest[1]) {
+ right_tb = (TranslationBlock *) atomic_read(tbs->tb->jmp_dest + 1);
+ }
+
+ if (left_tb) {
+ fputs_preorder_walk(left_tb->tb_stats, depth - 1, dot, log_flags);
+ fputs_jump(tbs, left_tb->tb_stats, dot);
+ }
+ if (right_tb) {
+ fputs_preorder_walk(right_tb->tb_stats, depth - 1, dot, log_flags);
+ fputs_jump(tbs, right_tb->tb_stats, dot);
+ }
+ }
+ }
+}
+
+struct PreorderInfo {
+ TBStatistics *tbs;
+ int depth;
+ int log_flags;
+};
+
+static void fputs_preorder_walk_safe(CPUState *cpu, run_on_cpu_data icmd)
+{
+ struct PreorderInfo *info = icmd.host_ptr;
+
+ GString *file_name = g_string_new(NULL);;
+ g_string_printf(file_name, "/tmp/qemu-cfg-tb-%d-%d.dot", id, info->depth);
+ FILE *dot = fopen(file_name->str, "w+");
+
+ fputs(
+ "digraph G {\n"
+ " mclimit=1.5;\n"
+ " rankdir=TD; ordering=out;\n"
+ " graph[fontsize=10 fontname=\"Verdana\"];\n"
+ " color=\"#efefef\";\n"
+ " node[shape=box style=filled fontsize=8 fontname=\"Verdana\" fillcolor=\"#efefef\"];\n"
+ " edge[fontsize=8 fontname=\"Verdana\"];\n"
+ , dot);
+
+ cfg_nodes = g_hash_table_new(NULL, NULL);
+ fputs_preorder_walk(info->tbs, info->depth, dot, info->log_flags);
+ g_hash_table_destroy(cfg_nodes);
+
+ fputs("}\n\0", dot);
+ fclose(dot);
+
+ qemu_log("CFG dumped: %s\n", file_name->str);
+
+ g_string_free(file_name, true);
+ g_free(info);
+}
+
+void dump_tb_cfg(int id, int depth, int log_flags)
+{
+ cfg_tb_id = 1;
+ root_count = 0;
+
+ /* do a pre-order walk in the CFG with a limited depth */
+ TBStatistics *root = get_tbstats_by_id(id);
+ if (root) {
+ root_count = root->executions.normal;
+ }
+
+ struct PreorderInfo *info = g_new(struct PreorderInfo, 1);
+ info->tbs = root;
+ info->depth = depth + 1;
+ info->log_flags = log_flags;
+ async_safe_run_on_cpu(first_cpu, fputs_preorder_walk_safe,
+ RUN_ON_CPU_HOST_PTR(info));
+}
+
+/* TBStatistic collection controls */
+
void enable_collect_tb_stats(void)
{
@@ -305,6 +305,13 @@ ETEXI
"dump flags can be used to set dump code level: out_asm in_asm op",
.cmd = hmp_info_tb,
},
+ {
+ .name = "cfg",
+ .args_type = "id:i,depth:i?,flags:s?",
+ .params = "id [depth flags]",
+ .help = "plot CFG around TB with the given id",
+ .cmd = hmp_info_cfg,
+ },
{
.name = "coverset",
.args_type = "coverage:i?",
@@ -155,6 +155,7 @@ void dump_tbs_info(int count, int sort_by, bool use_monitor);
*/
void dump_tb_info(int id, int log_mask, bool use_monitor);
+void dump_tb_cfg(int id, int depth, int log_flags);
/* TBStatistic collection controls */
void enable_collect_tb_stats(void);
@@ -556,6 +556,28 @@ static void hmp_info_tb(Monitor *mon, const QDict *qdict)
dump_tb_info(id, mask, true);
}
+static void hmp_info_cfg(Monitor *mon, const QDict *qdict)
+{
+ const int id = qdict_get_int(qdict, "id");
+ const int depth = qdict_get_try_int(qdict, "depth", 3);
+ const char *flags = qdict_get_try_str(qdict, "flags");
+ int mask;
+
+ if (!tcg_enabled()) {
+ error_report("TB information is only available with accel=tcg");
+ return;
+ }
+
+ mask = flags ? qemu_str_to_log_mask(flags) : CPU_LOG_TB_IN_ASM;
+
+ if (!mask) {
+ error_report("Unable to parse log flags, see 'help log'");
+ return;
+ }
+
+ dump_tb_cfg(id, depth, mask);
+}
+
static void hmp_info_coverset(Monitor *mon, const QDict *qdict)
{
int coverage;
Adding "info cfg id depth" commands to HMP. This command allow the exploration a TB neighbors by dumping [and opening] a .dot file with the TB CFG neighbors colorized by their hotness. The goal of this command is to allow the dynamic exploration of TCG behavior and code quality. Therefore, for now, a corresponding QMP command is not worthwhile. Signed-off-by: Vanderson M. do Rosario <vandersonmr2@gmail.com> --- accel/tcg/tb-stats.c | 164 ++++++++++++++++++++++++++++++++++++++++ hmp-commands-info.hx | 7 ++ include/exec/tb-stats.h | 1 + monitor/misc.c | 22 ++++++ 4 files changed, 194 insertions(+)