コード例 #1
0
ファイル: gc.c プロジェクト: PKUCloud/samsara-linux-3.11
static int gc_thread_func(void *data)
{
	struct f2fs_sb_info *sbi = data;
	wait_queue_head_t *wq = &sbi->gc_thread->gc_wait_queue_head;
	long wait_ms;

	wait_ms = GC_THREAD_MIN_SLEEP_TIME;

	do {
		if (try_to_freeze())
			continue;
		else
			wait_event_interruptible_timeout(*wq,
						kthread_should_stop(),
						msecs_to_jiffies(wait_ms));
		if (kthread_should_stop())
			break;

		if (sbi->sb->s_writers.frozen >= SB_FREEZE_WRITE) {
			wait_ms = GC_THREAD_MAX_SLEEP_TIME;
			continue;
		}

		/*
		 * [GC triggering condition]
		 * 0. GC is not conducted currently.
		 * 1. There are enough dirty segments.
		 * 2. IO subsystem is idle by checking the # of writeback pages.
		 * 3. IO subsystem is idle by checking the # of requests in
		 *    bdev's request list.
		 *
		 * Note) We have to avoid triggering GCs too much frequently.
		 * Because it is possible that some segments can be
		 * invalidated soon after by user update or deletion.
		 * So, I'd like to wait some time to collect dirty segments.
		 */
		if (!mutex_trylock(&sbi->gc_mutex))
			continue;

		if (!is_idle(sbi)) {
			wait_ms = increase_sleep_time(wait_ms);
			mutex_unlock(&sbi->gc_mutex);
			continue;
		}

		if (has_enough_invalid_blocks(sbi))
			wait_ms = decrease_sleep_time(wait_ms);
		else
			wait_ms = increase_sleep_time(wait_ms);

#ifdef CONFIG_F2FS_STAT_FS
		sbi->bg_gc++;
#endif

		/* if return value is not zero, no victim was selected */
		if (f2fs_gc(sbi))
			wait_ms = GC_THREAD_NOGC_SLEEP_TIME;
	} while (!kthread_should_stop());
	return 0;
}
コード例 #2
0
static int gc_thread_func(void *data)
{
	struct f2fs_sb_info *sbi = data;
	struct f2fs_gc_kthread *gc_th = sbi->gc_thread;
	wait_queue_head_t *wq = &sbi->gc_thread->gc_wait_queue_head;
	long wait_ms;

	wait_ms = gc_th->min_sleep_time;

	do {
		if (try_to_freeze())
			continue;
		else
			wait_event_interruptible_timeout(*wq,
						kthread_should_stop(),
						msecs_to_jiffies(wait_ms));
		if (kthread_should_stop())
			break;

		/*
		 * [GC triggering condition]
		 * 0. GC is not conducted currently.
		 * 1. There are enough dirty segments.
		 * 2. IO subsystem is idle by checking the # of writeback pages.
		 * 3. IO subsystem is idle by checking the # of requests in
		 *    bdev's request list.
		 *
		 * Note) We have to avoid triggering GCs too much frequently.
		 * Because it is possible that some segments can be
		 * invalidated soon after by user update or deletion.
		 * So, I'd like to wait some time to collect dirty segments.
		 */
		if (!mutex_trylock(&sbi->gc_mutex))
			continue;

		if (!is_idle(sbi)) {
			wait_ms = increase_sleep_time(gc_th, wait_ms);
			mutex_unlock(&sbi->gc_mutex);
			continue;
		}

		if (has_enough_invalid_blocks(sbi))
			wait_ms = decrease_sleep_time(gc_th, wait_ms);
		else
			wait_ms = increase_sleep_time(gc_th, wait_ms);

		stat_inc_bggc_count(sbi);

		/* if return value is not zero, no victim was selected */
		if (f2fs_gc(sbi))
			wait_ms = gc_th->no_gc_sleep_time;

		/* balancing f2fs's metadata periodically */
		f2fs_balance_fs_bg(sbi);

	} while (!kthread_should_stop());
	return 0;
}