Write a timer-debug-log file if enabled containing data about the
currently existing timers.
Signed-off-by: Alex Bligh <a...@alex.org.uk>
---
qemu-timer.c | 92 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 92 insertions(+)
diff --git a/qemu-timer.c b/qemu-timer.c
index 16eaa1f..cbce7ba 100644
--- a/qemu-timer.c
+++ b/qemu-timer.c
@@ -58,6 +58,7 @@ typedef struct QEMUClock {
QEMUTimerListGroup main_loop_tlg;
QEMUClock qemu_clocks[QEMU_CLOCK_MAX];
const char *timer_debug_log;
+static int64_t timer_last_debug;
/* A QEMUTimerList is a list of timers attached to a clock. More
* than one QEMUTimerList can be attached to each clock, for instance
@@ -396,6 +397,93 @@ static bool timer_mod_ns_locked(QEMUTimerList *timer_list,
return pt == &timer_list->active_timers;
}
+static void timer_debug(void)
+{
+ GString *debug_text;
+ GString *tmpfile;
+ QEMUClockType type;
+ FILE *f;
+ uint64_t now;
+
+ if (!timer_debug_log) {
+ return;
+ }
+
+ /* In order not to avoid influencing the output, we don't use a timer
+ * here, but use this disappointingly manual method.
+ */
+ now = qemu_clock_get_ns(QEMU_CLOCK_REALTIME);
+ if ((now - timer_last_debug) < 1000 * SCALE_MS) {
+ return;
+ }
+ timer_last_debug = now;
+
+ debug_text = g_string_new("");
+ tmpfile = g_string_new(timer_debug_log);
+ g_string_append(tmpfile, ".tmp");
+
+ for (type = 0; type < QEMU_CLOCK_MAX; type++) {
+ QEMUTimerList *timer_list;
+ QEMUClock *clock = qemu_clock_ptr(type);
+
+ /* Iteration through timerlists means we need the BQL held to
+ * call this safely.
+ */
+ QLIST_FOREACH(timer_list, &clock->timerlists, list) {
+ QEMUTimer *ts;
+
+ g_string_append_printf(debug_text, "\nTimer list at %p clock
%d:\n",
+ timer_list, (int) type);
+ g_string_append_printf(debug_text, "%18s %14s %14s %14s %s\n",
+ "Address",
+ "Expiries",
+ "AvgLength",
+ "NumShort",
+ "Source");
+ qemu_mutex_lock(&timer_list->active_timers_lock);
+ ts = timer_list->active_timers;
+ for (ts = timer_list->active_timers; ts; ts = ts->next) {
+ int64_t avg = -1;
+ if (ts->num_deltas) {
+ avg = (ts->tot_deltas + (ts->num_deltas/2)) /
+ ts->num_deltas;
+ }
+ const char *src = "unknown";
+ if (ts->dbg) {
+ const char *slash;
+ src = ts->dbg;
+ slash = strrchr(src, '/');
+ if (!slash) {
+ slash = strrchr(src, '\\');
+ }
+ if (slash) {
+ src = slash+1;
+ }
+ }
+
+ g_string_append_printf(debug_text, "%18p %14" PRId64 " %14"
+ PRId64 " %14" PRId64" %s\n",
+ ts,
+ ts->num_deltas,
+ avg,
+ ts->num_short,
+ src);
+ }
+ qemu_mutex_unlock(&timer_list->active_timers_lock);
+ }
+ }
+
+ f = fopen(tmpfile->str, "w");
+ if (f) {
+ fprintf(f, "%s", debug_text->str);
+ fclose(f);
+ rename(tmpfile->str, timer_debug_log);
+ }
+
+ g_string_free(tmpfile, true);
+ g_string_free(debug_text, true);
+}
+
static void timerlist_rearm(QEMUTimerList *timer_list)
{
/* Interrupt execution to force deadline recalculation. */
@@ -621,6 +709,10 @@ bool qemu_clock_run_all_timers(void)
bool progress = false;
QEMUClockType type;
+ if (timer_debug_log) {
+ timer_debug();
+ }
+
for (type = 0; type < QEMU_CLOCK_MAX; type++) {
progress |= qemu_clock_run_timers(type);
}
--
1.7.9.5
