static void update_writeback_rate(struct work_struct *work)
{
struct cached_dev *dc = container_of(to_delayed_work(work),
struct cached_dev,
writeback_rate_update);
struct cache_set *c = dc->disk.c;
/*
* should check BCACHE_DEV_RATE_DW_RUNNING before calling
* cancel_delayed_work_sync().
*/
set_bit(BCACHE_DEV_RATE_DW_RUNNING, &dc->disk.flags);
/* paired with where BCACHE_DEV_RATE_DW_RUNNING is tested */
smp_mb();
/*
* CACHE_SET_IO_DISABLE might be set via sysfs interface,
* check it here too.
*/
if (!test_bit(BCACHE_DEV_WB_RUNNING, &dc->disk.flags) ||
test_bit(CACHE_SET_IO_DISABLE, &c->flags)) {
clear_bit(BCACHE_DEV_RATE_DW_RUNNING, &dc->disk.flags);
/* paired with where BCACHE_DEV_RATE_DW_RUNNING is tested */
smp_mb();
return;
}
if (atomic_read(&dc->has_dirty) && dc->writeback_percent) {
/*
* If the whole cache set is idle, set_at_max_writeback_rate()
* will set writeback rate to a max number. Then it is
* unncessary to update writeback rate for an idle cache set
* in maximum writeback rate number(s).
*/
if (!set_at_max_writeback_rate(c, dc)) {
down_read(&dc->writeback_lock);
__update_writeback_rate(dc);
up_read(&dc->writeback_lock);
}
}
/*
* CACHE_SET_IO_DISABLE might be set via sysfs interface,
* check it here too.
*/
if (test_bit(BCACHE_DEV_WB_RUNNING, &dc->disk.flags) &&
!test_bit(CACHE_SET_IO_DISABLE, &c->flags)) {
schedule_delayed_work(&dc->writeback_rate_update,
dc->writeback_rate_update_seconds * HZ);
}
/*
* should check BCACHE_DEV_RATE_DW_RUNNING before calling
* cancel_delayed_work_sync().
*/
clear_bit(BCACHE_DEV_RATE_DW_RUNNING, &dc->disk.flags);
/* paired with where BCACHE_DEV_RATE_DW_RUNNING is tested */
smp_mb();
}
static void update_writeback_rate(struct work_struct *work)
{
struct cached_dev *dc = container_of(to_delayed_work(work),
struct cached_dev,
writeback_rate_update);
down_read(&dc->writeback_lock);
if (atomic_read(&dc->has_dirty) &&
dc->writeback_percent)
__update_writeback_rate(dc);
up_read(&dc->writeback_lock);
schedule_delayed_work(&dc->writeback_rate_update,
dc->writeback_rate_update_seconds * HZ);
}