[PATCH 1/3] io-wq: don't reshed if there is no work

From: Pavel Begunkov
Date: Fri Mar 13 2020 - 17:32:17 EST


This little tweak restores the behaviour that was before the recent
io_worker_handle_work() optimisation patches. It makes the function do
cond_resched() and flush_signals() only if there is an actual work to
execute.

Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx>
---
fs/io-wq.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/fs/io-wq.c b/fs/io-wq.c
index 0e7c6277afcb..8afe5565f57a 100644
--- a/fs/io-wq.c
+++ b/fs/io-wq.c
@@ -458,10 +458,12 @@ static void io_impersonate_work(struct io_worker *worker,
static void io_assign_current_work(struct io_worker *worker,
struct io_wq_work *work)
{
- /* flush pending signals before assigning new work */
- if (signal_pending(current))
- flush_signals(current);
- cond_resched();
+ if (work) {
+ /* flush pending signals before assigning new work */
+ if (signal_pending(current))
+ flush_signals(current);
+ cond_resched();
+ }

spin_lock_irq(&worker->lock);
worker->cur_work = work;
--
2.24.0