From e13fb1fe1483f6cd6452f25b866ffadf5ee0eff6 Mon Sep 17 00:00:00 2001
From: Hao Xu <haoxu@linux.alibaba.com>
Date: Sun, 6 Feb 2022 17:52:40 +0800
Subject: [PATCH] io-wq: reduce acct->lock crossing functions lock/unlock
Git-commit: e13fb1fe1483f6cd6452f25b866ffadf5ee0eff6
Patch-mainline: v5.18-rc1
References: bsc#1205205
reduce acct->lock lock and unlock in different functions to make the
code clearer.
Signed-off-by: Hao Xu <haoxu@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220206095241.121485-3-haoxu@linux.alibaba.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de>
---
fs/io-wq.c | 32 ++++++++++++--------------------
1 file changed, 12 insertions(+), 20 deletions(-)
--- a/fs/io-wq.c
+++ b/fs/io-wq.c
@@ -238,10 +238,15 @@ static void io_worker_exit(struct io_wor
static inline bool io_acct_run_queue(struct io_wqe_acct *acct)
{
+ bool ret = false;
+
+ raw_spin_lock(&acct->lock);
if (!wq_list_empty(&acct->work_list) &&
!test_bit(IO_ACCT_STALLED_BIT, &acct->flags))
- return true;
- return false;
+ ret = true;
+ raw_spin_unlock(&acct->lock);
+
+ return ret;
}
/*
@@ -394,13 +399,9 @@ static void io_wqe_dec_running(struct io
if (!atomic_dec_and_test(&acct->nr_running))
return;
- raw_spin_lock(&wqe->lock);
- if (!io_acct_run_queue(acct)) {
- raw_spin_unlock(&wqe->lock);
+ if (!io_acct_run_queue(acct))
return;
- }
- raw_spin_unlock(&wqe->lock);
atomic_inc(&acct->nr_running);
atomic_inc(&wqe->wq->worker_refs);
io_queue_worker_create(worker, acct, create_worker_cb);
@@ -543,7 +544,6 @@ static void io_assign_current_work(struc
static void io_wqe_enqueue(struct io_wqe *wqe, struct io_wq_work *work);
static void io_worker_handle_work(struct io_worker *worker)
- __releases(acct->lock)
{
struct io_wqe_acct *acct = io_wqe_get_acct(worker);
struct io_wqe *wqe = worker->wqe;
@@ -560,6 +560,7 @@ static void io_worker_handle_work(struct
* can't make progress, any work completion or insertion will
* clear the stalled flag.
*/
+ raw_spin_lock(&acct->lock);
work = io_get_next_work(acct, worker);
raw_spin_unlock(&acct->lock);
if (work) {
@@ -613,8 +614,6 @@ static void io_worker_handle_work(struct
wake_up(&wq->hash->wait);
}
} while (work);
-
- raw_spin_lock(&acct->lock);
} while (1);
}
@@ -636,14 +635,9 @@ static int io_wqe_worker(void *data)
long ret;
set_current_state(TASK_INTERRUPTIBLE);
-loop:
- raw_spin_lock(&acct->lock);
- if (io_acct_run_queue(acct)) {
+ while (io_acct_run_queue(acct))
io_worker_handle_work(worker);
- goto loop;
- } else {
- raw_spin_unlock(&acct->lock);
- }
+
raw_spin_lock(&wqe->lock);
/* timed out, exit unless we're the last worker */
if (last_timeout && acct->nr_workers > 1) {
@@ -668,10 +662,8 @@ loop:
last_timeout = !ret;
}
- if (test_bit(IO_WQ_BIT_EXIT, &wq->state)) {
- raw_spin_lock(&acct->lock);
+ if (test_bit(IO_WQ_BIT_EXIT, &wq->state))
io_worker_handle_work(worker);
- }
io_worker_exit(worker);
return 0;