io-wq: invoke work cancelation with wqe->lock held

io_wqe_cancel_pending_work() grabs it internally, grab it upfront
instead. For the running work cancelation, grab the lock around it as
well.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/fs/io-wq.c b/fs/io-wq.c
index c369910..a92fbdc 100644 (file)
--- a/fs/io-wq.c
+++ b/fs/io-wq.c
@@ -1038,17 +1038,16 @@ static void io_wqe_cancel_pending_work(struct io_wqe *wqe,
 {
        int i;
 retry:
-       raw_spin_lock(&wqe->lock);
        for (i = 0; i < IO_WQ_ACCT_NR; i++) {
                struct io_wqe_acct *acct = io_get_acct(wqe, i == 0);
 
                if (io_acct_cancel_pending_work(wqe, acct, match)) {
+                       raw_spin_lock(&wqe->lock);
                        if (match->cancel_all)
                                goto retry;
-                       return;
+                       break;
                }
        }
-       raw_spin_unlock(&wqe->lock);
 }
 
 static void io_wqe_cancel_running_work(struct io_wqe *wqe,
@@ -1077,7 +1076,9 @@ enum io_wq_cancel io_wq_cancel_cb(struct io_wq *wq, work_cancel_fn *cancel,
        for_each_node(node) {
                struct io_wqe *wqe = wq->wqes[node];
 
+               raw_spin_lock(&wqe->lock);
                io_wqe_cancel_pending_work(wqe, &match);
+               raw_spin_unlock(&wqe->lock);
                if (match.nr_pending && !match.cancel_all)
                        return IO_WQ_CANCEL_OK;
        }
@@ -1091,7 +1092,9 @@ enum io_wq_cancel io_wq_cancel_cb(struct io_wq *wq, work_cancel_fn *cancel,
        for_each_node(node) {
                struct io_wqe *wqe = wq->wqes[node];
 
+               raw_spin_lock(&wqe->lock);
                io_wqe_cancel_running_work(wqe, &match);
+               raw_spin_unlock(&wqe->lock);
                if (match.nr_running && !match.cancel_all)
                        return IO_WQ_CANCEL_RUNNING;
        }
@@ -1262,7 +1265,9 @@ static void io_wq_destroy(struct io_wq *wq)
                        .fn             = io_wq_work_match_all,
                        .cancel_all     = true,
                };
+               raw_spin_lock(&wqe->lock);
                io_wqe_cancel_pending_work(wqe, &match);
+               raw_spin_unlock(&wqe->lock);
                free_cpumask_var(wqe->cpu_mask);
                kfree(wqe);
        }