From 16efa4fce3b7af17bb45d635c3e89992d721e0f3 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Fri, 12 Mar 2021 20:26:13 -0700 Subject: io_uring: allow IO worker threads to be frozen With the freezer using the proper signaling to notify us of when it's time to freeze a thread, we can re-enable normal freezer usage for the IO threads. Ensure that SQPOLL, io-wq, and the io-wq manager call try_to_freeze() appropriately, and remove the default setting of PF_NOFREEZE from create_io_thread(). Signed-off-by: Jens Axboe --- fs/io-wq.c | 6 +++++- fs/io_uring.c | 1 + kernel/fork.c | 1 - 3 files changed, 6 insertions(+), 2 deletions(-) diff --git a/fs/io-wq.c b/fs/io-wq.c index 0ae9ecadf295..e05f996d088f 100644 --- a/fs/io-wq.c +++ b/fs/io-wq.c @@ -488,6 +488,8 @@ static int io_wqe_worker(void *data) set_task_comm(current, buf); while (!test_bit(IO_WQ_BIT_EXIT, &wq->state)) { + long ret; + set_current_state(TASK_INTERRUPTIBLE); loop: raw_spin_lock_irq(&wqe->lock); @@ -498,7 +500,8 @@ loop: __io_worker_idle(wqe, worker); raw_spin_unlock_irq(&wqe->lock); io_flush_signals(); - if (schedule_timeout(WORKER_IDLE_TIMEOUT)) + ret = schedule_timeout(WORKER_IDLE_TIMEOUT); + if (try_to_freeze() || ret) continue; if (fatal_signal_pending(current)) break; @@ -709,6 +712,7 @@ static int io_wq_manager(void *data) set_current_state(TASK_INTERRUPTIBLE); io_wq_check_workers(wq); schedule_timeout(HZ); + try_to_freeze(); if (fatal_signal_pending(current)) set_bit(IO_WQ_BIT_EXIT, &wq->state); } while (!test_bit(IO_WQ_BIT_EXIT, &wq->state)); diff --git a/fs/io_uring.c b/fs/io_uring.c index a4bce17af506..05adc4887ef3 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -6752,6 +6752,7 @@ static int io_sq_thread(void *data) up_read(&sqd->rw_lock); schedule(); + try_to_freeze(); down_read(&sqd->rw_lock); list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) io_ring_clear_wakeup_flag(ctx); diff --git a/kernel/fork.c b/kernel/fork.c index 72e444cd0ffe..d3171e8e88e5 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -2436,7 +2436,6 @@ struct task_struct *create_io_thread(int (*fn)(void *), void *arg, int node) if (!IS_ERR(tsk)) { sigfillset(&tsk->blocked); sigdelsetmask(&tsk->blocked, sigmask(SIGKILL)); - tsk->flags |= PF_NOFREEZE; } return tsk; } -- cgit v1.2.3