Adding tb_stats [start|pause|stop|filter] command to hmp.
This allows controlling the collection of statistics.
It is also possible to set the level of collection:
all, jit, or exec.
The goal of this command is to allow the dynamic exploration
of the TCG behavior and quality. Therefore, for now, a
corresponding QMP command is not worthwhile.
Signed-off-by: Vanderson M. do Rosario <vanderson...@gmail.com>
---
accel/tcg/tb-stats.c | 107 ++++++++++++++++++++++++++++++++++++++++
hmp-commands.hx | 17 +++++++
include/exec/tb-stats.h | 13 +++++
include/qemu/log.h | 1 +
monitor/misc.c | 40 +++++++++++++++
5 files changed, 178 insertions(+)
diff --git a/accel/tcg/tb-stats.c b/accel/tcg/tb-stats.c
index 44497d4f9b..6c330e1b02 100644
--- a/accel/tcg/tb-stats.c
+++ b/accel/tcg/tb-stats.c
@@ -6,6 +6,9 @@
#include "qemu/qemu-print.h"
+/* only accessed in safe work */
+static GList *last_search;
+
struct jit_profile_info {
uint64_t translations;
uint64_t aborted;
@@ -104,4 +107,108 @@ void dump_jit_profile_info(TCGProfile *s)
}
}
+static void dessaloc_tbstats(void *p, uint32_t hash, void *userp)
+{
+ g_free(p);
+}
+
+void clean_tbstats(void)
+{
+ /* remove all tb_stats */
+ qht_iter(&tb_ctx.tb_stats, dessaloc_tbstats, NULL);
+ qht_destroy(&tb_ctx.tb_stats);
+}
+
+static void reset_tbstats_flag(void *p, uint32_t hash, void *userp)
+{
+ uint32_t flag = *((int *)userp);
+ TBStatistics *tbs = p;
+ tbs->stats_enabled = flag;
+}
+
+void set_tbstats_flags(uint32_t flag)
+{
+ /* iterate over tbstats setting their flag as TB_NOTHING */
+ qht_iter(&tb_ctx.tb_stats, reset_tbstats_flag, &flag);
+}
+
+void do_hmp_tbstats_safe(CPUState *cpu, run_on_cpu_data icmd)
+{
+ struct TbstatsCommand *cmdinfo = icmd.host_ptr;
+ int cmd = cmdinfo->cmd;
+ uint32_t level = cmdinfo->level;
+
+ /* for safe, always pause TB generation while running this commands */
+ mmap_lock();
+
+ switch (cmd) {
+ case START:
+ if (tb_stats_collection_paused()) {
+ set_tbstats_flags(level);
+ } else {
+ if (tb_stats_collection_enabled()) {
+ qemu_printf("TB information already being recorded");
+ return;
+ }
+ qht_init(&tb_ctx.tb_stats, tb_stats_cmp, CODE_GEN_HTABLE_SIZE,
+ QHT_MODE_AUTO_RESIZE);
+ }
+
+ set_default_tbstats_flag(level);
+ enable_collect_tb_stats();
+ tb_flush(cpu);
+ break;
+ case PAUSE:
+ if (!tb_stats_collection_enabled()) {
+ qemu_printf("TB information not being recorded");
+ return;
+ }
+
+ /* Continue to create TBStatistic structures but stop collecting
statistics */
+ pause_collect_tb_stats();
+ tb_flush(cpu);
+ set_default_tbstats_flag(TB_NOTHING);
+ set_tbstats_flags(TB_PAUSED);
+ break;
+ case STOP:
+ if (!tb_stats_collection_enabled()) {
+ qemu_printf("TB information not being recorded");
+ return;
+ }
+
+ /* Dissalloc all TBStatistics structures and stop creating new ones */
+ disable_collect_tb_stats();
+ tb_flush(cpu);
+ clean_tbstats();
+ break;
+ case FILTER:
+ if (!tb_stats_collection_enabled()) {
+ qemu_printf("TB information not being recorded");
+ return;
+ }
+ if (!last_search) {
+ qemu_printf("no search on record! execute info tbs before
filtering!");
+ return;
+ }
+
+ tb_flush(cpu);
+ set_default_tbstats_flag(TB_NOTHING);
+
+ /* Set all tbstats as paused, then return only the ones from
last_search */
+ pause_collect_tb_stats();
+ set_tbstats_flags(TB_PAUSED);
+
+ for (GList *iter = last_search; iter; iter = g_list_next(iter)) {
+ TBStatistics *tbs = iter->data;
+ tbs->stats_enabled = level;
+ }
+
+ break;
+ default: /* INVALID */
+ break;
+ }
+
+ mmap_unlock();
+ g_free(cmdinfo);
+}
diff --git a/hmp-commands.hx b/hmp-commands.hx
index bfa5681dd2..419898751e 100644
--- a/hmp-commands.hx
+++ b/hmp-commands.hx
@@ -1885,6 +1885,23 @@ STEXI
@findex qemu-io
Executes a qemu-io command on the given block device.
+ETEXI
+#if defined(CONFIG_TCG)
+ {
+ .name = "tb_stats",
+ .args_type = "command:s,level:s?",
+ .params = "command [stats_level]",
+ .help = "Control tb statistics collection:"
+ "tb_stats (start|pause|stop|filter)
[all|jit_stats|exec_stats]",
+ .cmd = hmp_tbstats,
+ },
+#endif
+
+STEXI
+@item tb_stats
+@findex
+Control recording tb statistics
+
ETEXI
{
diff --git a/include/exec/tb-stats.h b/include/exec/tb-stats.h
index 7d775f2c0d..d1debd3262 100644
--- a/include/exec/tb-stats.h
+++ b/include/exec/tb-stats.h
@@ -6,6 +6,9 @@
#include "exec/tb-context.h"
#include "tcg.h"
+enum SortBy { SORT_BY_HOTNESS, SORT_BY_HG /* Host/Guest */, SORT_BY_SPILLS };
+enum TbstatsCmd { START, PAUSE, STOP, FILTER };
+
#define tb_stats_enabled(tb, JIT_STATS) \
(tb && tb->tb_stats && (tb->tb_stats->stats_enabled & JIT_STATS))
@@ -60,4 +63,14 @@ bool tb_stats_cmp(const void *ap, const void *bp);
void dump_jit_profile_info(TCGProfile *s);
+void set_tbstats_flags(uint32_t flags);
+void clean_tbstats(void);
+
+struct TbstatsCommand {
+ enum TbstatsCmd cmd;
+ uint32_t level;
+};
+
+void do_hmp_tbstats_safe(CPUState *cpu, run_on_cpu_data icmd);
+
#endif
diff --git a/include/qemu/log.h b/include/qemu/log.h
index 93642603e5..47071d72c7 100644
--- a/include/qemu/log.h
+++ b/include/qemu/log.h
@@ -133,6 +133,7 @@ void qemu_log_close(void);
#define TB_NOTHING 0
#define TB_EXEC_STATS (1 << 1)
#define TB_JIT_STATS (1 << 2)
+#define TB_PAUSED (1 << 3)
void enable_collect_tb_stats(void);
void disable_collect_tb_stats(void);
diff --git a/monitor/misc.c b/monitor/misc.c
index 00338c002a..aea9b0db4f 100644
--- a/monitor/misc.c
+++ b/monitor/misc.c
@@ -459,6 +459,46 @@ static void hmp_info_registers(Monitor *mon, const QDict
*qdict)
}
#ifdef CONFIG_TCG
+static void hmp_tbstats(Monitor *mon, const QDict *qdict)
+{
+ if (!tcg_enabled()) {
+ error_report("TB information is only available with accel=tcg");
+ return;
+ }
+
+ char *cmd = (char *) qdict_get_try_str(qdict, "command");
+ enum TbstatsCmd icmd = -1;
+
+ if (strcmp(cmd, "start") == 0) {
+ icmd = START;
+ } else if (strcmp(cmd, "pause") == 0) {
+ icmd = PAUSE;
+ } else if (strcmp(cmd, "stop") == 0) {
+ icmd = STOP;
+ } else if (strcmp(cmd, "filter") == 0) {
+ icmd = FILTER;
+ } else {
+ error_report("invalid command!");
+ }
+
+ char *slevel = (char *) qdict_get_try_str(qdict, "level");
+ uint32_t level = TB_EXEC_STATS | TB_JIT_STATS;
+ if (slevel) {
+ if (strcmp(slevel, "jit_stats") == 0) {
+ level = TB_JIT_STATS;
+ } else if (strcmp(slevel, "exec_stats") == 0) {
+ level = TB_EXEC_STATS;
+ }
+ }
+
+ struct TbstatsCommand *tbscommand = g_new0(struct TbstatsCommand, 1);
+ tbscommand->cmd = icmd;
+ tbscommand->level = level;
+ async_safe_run_on_cpu(first_cpu, do_hmp_tbstats_safe,
+ RUN_ON_CPU_HOST_PTR(tbscommand));
+
+}
+
static void hmp_info_jit(Monitor *mon, const QDict *qdict)
{
if (!tcg_enabled()) {
--
2.22.0
