From 33c0dd7898a11ef19169abe5c5049fa6aa099c64 Mon Sep 17 00:00:00 2001
From: Dave Chinner <dchinner@redhat.com>
Date: Tue, 10 Aug 2021 18:00:45 -0700
Subject: [PATCH] xfs: move the CIL workqueue to the CIL
Git-commit: 33c0dd7898a11ef19169abe5c5049fa6aa099c64
Patch-mainline: v5.15-rc1
References: bsc#1211811

We only use the CIL workqueue in the CIL, so it makes no sense to
hang it off the xfs_mount and have to walk multiple pointers back up
to the mount when we have the CIL structures right there.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Acked-by: Anthony Iliopoulos <ailiop@suse.com>

---
 fs/xfs/xfs_log_cil.c  |   20 +++++++++++++++++---
 fs/xfs/xfs_log_priv.h |    1 +
 fs/xfs/xfs_mount.h    |    1 -
 fs/xfs/xfs_super.c    |   15 +--------------
 4 files changed, 19 insertions(+), 18 deletions(-)

--- a/fs/xfs/xfs_log_cil.c
+++ b/fs/xfs/xfs_log_cil.c
@@ -1143,7 +1143,7 @@ xlog_cil_push_background(
 	spin_lock(&cil->xc_push_lock);
 	if (cil->xc_push_seq < cil->xc_current_sequence) {
 		cil->xc_push_seq = cil->xc_current_sequence;
-		queue_work(log->l_mp->m_cil_workqueue, &cil->xc_ctx->push_work);
+		queue_work(cil->xc_push_wq, &cil->xc_ctx->push_work);
 	}
 
 	/*
@@ -1209,7 +1209,7 @@ xlog_cil_push_now(
 
 	/* start on any pending background push to minimise wait time on it */
 	if (!async)
-		flush_workqueue(log->l_mp->m_cil_workqueue);
+		flush_workqueue(cil->xc_push_wq);
 
 	/*
 	 * If the CIL is empty or we've already pushed the sequence then
@@ -1223,7 +1223,7 @@ xlog_cil_push_now(
 
 	cil->xc_push_seq = push_seq;
 	cil->xc_push_commit_stable = async;
-	queue_work(log->l_mp->m_cil_workqueue, &cil->xc_ctx->push_work);
+	queue_work(cil->xc_push_wq, &cil->xc_ctx->push_work);
 	spin_unlock(&cil->xc_push_lock);
 }
 
@@ -1462,6 +1462,15 @@ xlog_cil_init(
 	cil = kmem_zalloc(sizeof(*cil), KM_MAYFAIL);
 	if (!cil)
 		return -ENOMEM;
+	/*
+	 * Limit the CIL pipeline depth to 4 concurrent works to bound the
+	 * concurrency the log spinlocks will be exposed to.
+	 */
+	cil->xc_push_wq = alloc_workqueue("xfs-cil/%s",
+			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM | WQ_UNBOUND),
+			4, log->l_mp->m_super->s_id);
+	if (!cil->xc_push_wq)
+		goto out_destroy_cil;
 
 	INIT_LIST_HEAD(&cil->xc_cil);
 	INIT_LIST_HEAD(&cil->xc_committing);
@@ -1478,6 +1487,10 @@ xlog_cil_init(
 	xlog_cil_ctx_switch(cil, ctx);
 
 	return 0;
+
+out_destroy_cil:
+	kmem_free(cil);
+	return -ENOMEM;
 }
 
 void
@@ -1491,6 +1504,7 @@ xlog_cil_destroy(
 	}
 
 	ASSERT(list_empty(&log->l_cilp->xc_cil));
+	destroy_workqueue(log->l_cilp->xc_push_wq);
 	kmem_free(log->l_cilp);
 }
 
--- a/fs/xfs/xfs_log_priv.h
+++ b/fs/xfs/xfs_log_priv.h
@@ -281,6 +281,7 @@ struct xfs_cil {
 	struct xlog		*xc_log;
 	struct list_head	xc_cil;
 	spinlock_t		xc_cil_lock;
+	struct workqueue_struct	*xc_push_wq;
 
 	struct rw_semaphore	xc_ctx_lock ____cacheline_aligned_in_smp;
 	struct xfs_cil_ctx	*xc_ctx;
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -92,7 +92,6 @@ typedef struct xfs_mount {
 	struct xfs_mru_cache	*m_filestream;  /* per-mount filestream data */
 	struct workqueue_struct *m_buf_workqueue;
 	struct workqueue_struct	*m_unwritten_workqueue;
-	struct workqueue_struct	*m_cil_workqueue;
 	struct workqueue_struct	*m_reclaim_workqueue;
 	struct workqueue_struct *m_gc_workqueue;
 	struct workqueue_struct	*m_sync_workqueue;
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -501,21 +501,11 @@ xfs_init_mount_workqueues(
 	if (!mp->m_unwritten_workqueue)
 		goto out_destroy_buf;
 
-	/*
-	 * Limit the CIL pipeline depth to 4 concurrent works to bound the
-	 * concurrency the log spinlocks will be exposed to.
-	 */
-	mp->m_cil_workqueue = alloc_workqueue("xfs-cil/%s",
-			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM | WQ_UNBOUND),
-			4, mp->m_super->s_id);
-	if (!mp->m_cil_workqueue)
-		goto out_destroy_unwritten;
-
 	mp->m_reclaim_workqueue = alloc_workqueue("xfs-reclaim/%s",
 			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM),
 			0, mp->m_super->s_id);
 	if (!mp->m_reclaim_workqueue)
-		goto out_destroy_cil;
+		goto out_destroy_unwritten;
 
 	mp->m_gc_workqueue = alloc_workqueue("xfs-gc/%s",
 			WQ_SYSFS | WQ_UNBOUND | WQ_FREEZABLE | WQ_MEM_RECLAIM,
@@ -534,8 +524,6 @@ out_destroy_eofb:
 	destroy_workqueue(mp->m_gc_workqueue);
 out_destroy_reclaim:
 	destroy_workqueue(mp->m_reclaim_workqueue);
-out_destroy_cil:
-	destroy_workqueue(mp->m_cil_workqueue);
 out_destroy_unwritten:
 	destroy_workqueue(mp->m_unwritten_workqueue);
 out_destroy_buf:
@@ -551,7 +539,6 @@ xfs_destroy_mount_workqueues(
 	destroy_workqueue(mp->m_sync_workqueue);
 	destroy_workqueue(mp->m_gc_workqueue);
 	destroy_workqueue(mp->m_reclaim_workqueue);
-	destroy_workqueue(mp->m_cil_workqueue);
 	destroy_workqueue(mp->m_unwritten_workqueue);
 	destroy_workqueue(mp->m_buf_workqueue);
 }