From 0c9d5ccd26a004f59333c06fbbb98f9cb1eed93d Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Wed, 11 Dec 2019 19:29:43 -0700 Subject: io-wq: add support for uncancellable work Not all work can be cancelled, some of it we may need to guarantee that it runs to completion. Allow the caller to set IO_WQ_WORK_NO_CANCEL on work that must not be cancelled. Note that the caller work function must also check for IO_WQ_WORK_NO_CANCEL on work that is marked IO_WQ_WORK_CANCEL. Signed-off-by: Jens Axboe --- fs/io-wq.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'fs/io-wq.c') diff --git a/fs/io-wq.c b/fs/io-wq.c index 5147d2213b01..79eae29983ca 100644 --- a/fs/io-wq.c +++ b/fs/io-wq.c @@ -456,6 +456,10 @@ next: } if (!worker->creds) worker->creds = override_creds(wq->creds); + /* + * OK to set IO_WQ_WORK_CANCEL even for uncancellable work, + * the worker function will do the right thing. + */ if (test_bit(IO_WQ_BIT_CANCEL, &wq->state)) work->flags |= IO_WQ_WORK_CANCEL; if (worker->mm) @@ -828,6 +832,7 @@ static bool io_work_cancel(struct io_worker *worker, void *cancel_data) */ spin_lock_irqsave(&worker->lock, flags); if (worker->cur_work && + !(worker->cur_work->flags & IO_WQ_WORK_NO_CANCEL) && data->cancel(worker->cur_work, data->caller_data)) { send_sig(SIGINT, worker->task, 1); ret = true; @@ -902,7 +907,8 @@ static bool io_wq_worker_cancel(struct io_worker *worker, void *data) return false; spin_lock_irqsave(&worker->lock, flags); - if (worker->cur_work == work) { + if (worker->cur_work == work && + !(worker->cur_work->flags & IO_WQ_WORK_NO_CANCEL)) { send_sig(SIGINT, worker->task, 1); ret = true; } -- cgit v1.2.3