diff options
| author | Jens Axboe <axboe@kernel.dk> | 2021-03-09 19:49:02 -0700 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2021-03-10 07:28:43 -0700 |
| commit | e22bc9b481a90d7898984ea17621f04a653e2cd1 (patch) | |
| tree | 9c7f6a4821f3afecdbeca3eb07e2d397e0a3dc4c | |
| parent | e8f98f24549d62cc54bf608c815904a56d4437bc (diff) | |
| download | linux-e22bc9b481a90d7898984ea17621f04a653e2cd1.tar.gz | |
kernel: make IO threads unfreezable by default
The io-wq threads were already marked as no-freeze, but the manager was
not. On resume, we perpetually have signal_pending() being true, and
hence the manager will loop and spin 100% of the time.
Just mark the tasks created by create_io_thread() as PF_NOFREEZE by
default, and remove any knowledge of it in io-wq and io_uring.
Reported-by: Kevin Locke <kevin@kevinlocke.name>
Tested-by: Kevin Locke <kevin@kevinlocke.name>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | fs/io-wq.c | 3 | ||||
| -rw-r--r-- | fs/io_uring.c | 1 | ||||
| -rw-r--r-- | kernel/fork.c | 1 |
3 files changed, 2 insertions, 3 deletions
diff --git a/fs/io-wq.c b/fs/io-wq.c index 3d7060ba547a03..0ae9ecadf295ce 100644 --- a/fs/io-wq.c +++ b/fs/io-wq.c @@ -591,7 +591,7 @@ static bool create_io_worker(struct io_wq *wq, struct io_wqe *wqe, int index) tsk->pf_io_worker = worker; worker->task = tsk; set_cpus_allowed_ptr(tsk, cpumask_of_node(wqe->node)); - tsk->flags |= PF_NOFREEZE | PF_NO_SETAFFINITY; + tsk->flags |= PF_NO_SETAFFINITY; raw_spin_lock_irq(&wqe->lock); hlist_nulls_add_head_rcu(&worker->nulls_node, &wqe->free_list); @@ -709,7 +709,6 @@ 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 62f998bf2ce843..14165e18020c16 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -6733,7 +6733,6 @@ 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 d3171e8e88e5d4..72e444cd0ffed2 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -2436,6 +2436,7 @@ 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; } |