From: Timo Sirainen <timo.sirainen@dovecot.fi>
Date: Tue, 15 Nov 2016 10:21:56 +0000 (+0100)
Subject: lib: Added io_wait_timer
X-Git-Tag: 2.2.27~162
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=4c8b67114485a33f107747bba8bff88fde8f315f;p=thirdparty%2Fdovecot%2Fcore.git

lib: Added io_wait_timer

This allows easier tracking of how much time the io_wait_timer has been
spending on (multiple) ioloops.
---

diff --git a/src/lib/ioloop-private.h b/src/lib/ioloop-private.h
index 97d20749ee..a4b879f9c2 100644
--- a/src/lib/ioloop-private.h
+++ b/src/lib/ioloop-private.h
@@ -18,6 +18,7 @@ struct ioloop {
 	struct io_file *next_io_file;
 	struct priorityq *timeouts;
 	ARRAY(struct timeout *) timeouts_new;
+	struct io_wait_timer *wait_timers;
 
         struct ioloop_handler_context *handler_context;
         struct ioloop_notify_handler_context *notify_handler_context;
@@ -79,6 +80,15 @@ struct timeout {
 	unsigned int one_shot:1;
 };
 
+struct io_wait_timer {
+	struct io_wait_timer *prev, *next;
+	const char *source_filename;
+	unsigned int source_linenum;
+
+	struct ioloop *ioloop;
+	uint64_t usecs;
+};
+
 struct ioloop_context_callback {
 	io_callback_t *activate;
 	io_callback_t *deactivate;
diff --git a/src/lib/ioloop.c b/src/lib/ioloop.c
index 59a1219c09..a04b98765e 100644
--- a/src/lib/ioloop.c
+++ b/src/lib/ioloop.c
@@ -2,6 +2,7 @@
 
 #include "lib.h"
 #include "array.h"
+#include "llist.h"
 #include "time-util.h"
 #include "istream-private.h"
 #include "ioloop-private.h"
@@ -499,10 +500,14 @@ static void io_loops_timeouts_update(long diff_secs)
 
 static void ioloop_add_wait_time(struct ioloop *ioloop)
 {
+	struct io_wait_timer *timer;
 	long long diff =
 		timeval_diff_usecs(&ioloop_timeval, &ioloop->wait_started);
 	ioloop->ioloop_wait_usecs += diff;
 	ioloop_global_wait_usecs += diff;
+
+	for (timer = ioloop->wait_timers; timer != NULL; timer = timer->next)
+		timer->usecs += diff;
 }
 
 static void io_loop_handle_timeouts_real(struct ioloop *ioloop)
@@ -740,6 +745,15 @@ void io_loop_destroy(struct ioloop **_ioloop)
 	}
 	priorityq_deinit(&ioloop->timeouts);
 
+	while (ioloop->wait_timers != NULL) {
+		struct io_wait_timer *timer = ioloop->wait_timers;
+
+		i_warning("IO wait timer leak: %s:%u",
+			  timer->source_filename,
+			  timer->source_linenum);
+		io_wait_timer_remove(&timer);
+	}
+
 	if (ioloop->handler_context != NULL)
 		io_loop_handler_deinit(ioloop);
 
@@ -1002,3 +1016,42 @@ enum io_condition io_loop_find_fd_conditions(struct ioloop *ioloop, int fd)
 	}
 	return conditions;
 }
+
+#undef io_wait_timer_add
+struct io_wait_timer *
+io_wait_timer_add(const char *source_filename, unsigned int source_linenum)
+{
+	struct io_wait_timer *timer;
+
+	timer = i_new(struct io_wait_timer, 1);
+	timer->ioloop = current_ioloop;
+	timer->source_filename = source_filename;
+	timer->source_linenum = source_linenum;
+	DLLIST_PREPEND(&current_ioloop->wait_timers, timer);
+	return timer;
+}
+
+struct io_wait_timer *io_wait_timer_move(struct io_wait_timer **_timer)
+{
+	struct io_wait_timer *timer = *_timer;
+
+	*_timer = NULL;
+	DLLIST_REMOVE(&timer->ioloop->wait_timers, timer);
+	DLLIST_PREPEND(&current_ioloop->wait_timers, timer);
+	timer->ioloop = current_ioloop;
+	return timer;
+}
+
+void io_wait_timer_remove(struct io_wait_timer **_timer)
+{
+	struct io_wait_timer *timer = *_timer;
+
+	*_timer = NULL;
+	DLLIST_REMOVE(&timer->ioloop->wait_timers, timer);
+	i_free(timer);
+}
+
+uint64_t io_wait_timer_get_usecs(struct io_wait_timer *timer)
+{
+	return timer->usecs;
+}
diff --git a/src/lib/ioloop.h b/src/lib/ioloop.h
index c33d841064..f42e7286b0 100644
--- a/src/lib/ioloop.h
+++ b/src/lib/ioloop.h
@@ -183,6 +183,18 @@ struct ioloop_context *io_loop_get_current_context(struct ioloop *ioloop);
    Returns fd on success, -1 on error. */
 int io_loop_extract_notify_fd(struct ioloop *ioloop);
 
+/* IO wait timers can be used to track how much time the io_wait_timer has
+   spent on waiting in its ioloops. This is similar to
+   io_loop_get_wait_usecs(), but it's easier to use when the wait time needs
+   to be tracked across multiple ioloops. */
+struct io_wait_timer *
+io_wait_timer_add(const char *source_filename, unsigned int source_linenum);
+#define io_wait_timer_add() \
+	io_wait_timer_add(__FILE__, __LINE__)
+struct io_wait_timer *io_wait_timer_move(struct io_wait_timer **timer);
+void io_wait_timer_remove(struct io_wait_timer **timer);
+uint64_t io_wait_timer_get_usecs(struct io_wait_timer *timer);
+
 /* Move the given I/O into the current I/O loop if it's not already
    there. New I/O is returned, while the old one is freed. */
 struct io *io_loop_move_io(struct io **io);