diff options
| -rw-r--r-- | fs/fs-writeback.c | 46 |
1 files changed, 14 insertions, 32 deletions
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 628235c..783ed44 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -75,13 +75,6 @@ static inline void bdi_work_init(struct bdi_work *work, work->state = WS_USED; } -static inline void bdi_work_init_on_stack(struct bdi_work *work, - struct writeback_control *wbc) -{ - bdi_work_init(work, wbc); - work->state |= WS_ONSTACK; -} - /** * writeback_in_progress - determine whether there is writeback in progress * @bdi: the device's backing_dev_info structure. @@ -207,34 +200,23 @@ static struct bdi_work *bdi_alloc_work(struct writeback_control *wbc) void bdi_start_writeback(struct writeback_control *wbc) { - const bool must_wait = wbc->sync_mode == WB_SYNC_ALL; - struct bdi_work work_stack, *work = NULL; - - if (!must_wait) - work = bdi_alloc_work(wbc); + /* + * WB_SYNC_NONE is opportunistic writeback. If this allocation fails, + * bdi_queue_work() will wake up the thread and flush old data. This + * should ensure some amount of progress in freeing memory. + */ + if (wbc->sync_mode != WB_SYNC_ALL) { + struct bdi_work *w = bdi_alloc_work(wbc); - if (!work) { - work = &work_stack; - bdi_work_init_on_stack(work, wbc); - } + bdi_queue_work(wbc->bdi, w); + } else { + struct bdi_work work; - bdi_queue_work(wbc->bdi, work); + bdi_work_init(&work, wbc); + work.state |= WS_ONSTACK; - /* - * If the sync mode is WB_SYNC_ALL, block waiting for the work to - * complete. If not, we only need to wait for the work to be started, - * if we allocated it on-stack. We use the same mechanism, if the - * wait bit is set in the bdi_work struct, then threads will not - * clear pending until after they are done. - * - * Note that work == &work_stack if must_wait is true, so we don't - * need to do call_rcu() here ever, since the completion path will - * have done that for us. - */ - if (must_wait || work == &work_stack) { - bdi_wait_on_work_clear(work); - if (work != &work_stack) - call_rcu(&work->rcu_head, bdi_work_free); + bdi_queue_work(wbc->bdi, &work); + bdi_wait_on_work_clear(&work); } } |
