From: Christoph Hellwig <hch@lst.de>
Date: Thu, 9 Dec 2021 07:31:23 +0100
Subject: [PATCH] block: refactor put_iocontext_active
Git-commit: 4be8a2eaff2e4473b6e8ad9a3857bc9b1e79c8ba
Patch-mainline: v5.17-rc1
References: jsc#PED-1183

Factor out a ioc_exit_icqs helper to tear down the icqs and the fold
the rest of put_iocontext_active into exit_io_context.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20211209063131.18537-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Hannes Reinecke <hare@suse.com>
---
 block/blk-ioc.c | 41 ++++++++++++++---------------------------
 1 file changed, 14 insertions(+), 27 deletions(-)

diff --git a/block/blk-ioc.c b/block/blk-ioc.c
index 9cde3906be3c..0380e33930e3 100644
--- a/block/blk-ioc.c
+++ b/block/blk-ioc.c
@@ -54,6 +54,16 @@ static void ioc_exit_icq(struct io_cq *icq)
 	icq->flags |= ICQ_EXITED;
 }
 
+static void ioc_exit_icqs(struct io_context *ioc)
+{
+	struct io_cq *icq;
+
+	spin_lock_irq(&ioc->lock);
+	hlist_for_each_entry(icq, &ioc->icq_list, ioc_node)
+		ioc_exit_icq(icq);
+	spin_unlock_irq(&ioc->lock);
+}
+
 /*
  * Release an icq. Called with ioc locked for blk-mq, and with both ioc
  * and queue locked for legacy.
@@ -169,32 +179,6 @@ void put_io_context(struct io_context *ioc)
 }
 EXPORT_SYMBOL_GPL(put_io_context);
 
-/**
- * put_io_context_active - put active reference on ioc
- * @ioc: ioc of interest
- *
- * Put an active reference to an ioc.  If active reference reaches zero after
- * put, @ioc can never issue further IOs and ioscheds are notified.
- */
-static void put_io_context_active(struct io_context *ioc)
-{
-	struct io_cq *icq;
-
-	if (!atomic_dec_and_test(&ioc->active_ref))
-		return;
-
-	spin_lock_irq(&ioc->lock);
-	hlist_for_each_entry(icq, &ioc->icq_list, ioc_node) {
-		if (icq->flags & ICQ_EXITED)
-			continue;
-
-		ioc_exit_icq(icq);
-	}
-	spin_unlock_irq(&ioc->lock);
-
-	put_io_context(ioc);
-}
-
 /* Called by the exiting task */
 void exit_io_context(struct task_struct *task)
 {
@@ -205,7 +189,10 @@ void exit_io_context(struct task_struct *task)
 	task->io_context = NULL;
 	task_unlock(task);
 
-	put_io_context_active(ioc);
+	if (atomic_dec_and_test(&ioc->active_ref)) {
+		ioc_exit_icqs(ioc);
+		put_io_context(ioc);
+	}
 }
 
 static void __ioc_clear_queue(struct list_head *icq_list)
-- 
2.35.3