Re: [PATCH] btrfs: Drop WQ_PERCPU from ordered_flags in btrfs_init_workqueues()

[Breno Leitao]

On Mon, Jun 01, 2026 at 07:46:26PM -0700, Nathan Chancellor wrote:
> After commit 21c05ca88a54 ("workqueue: Add warnings and ensure one among
> WQ_PERCPU or WQ_UNBOUND is present"), there is a warning from the
> btrfs-qgroup-rescan workqueue at run time:
> 
>   workqueue: btrfs-qgroup-rescan uses both WQ_PERCPU and WQ_UNBOUND. Dropped WQ_PERCPU, keeping WQ_UNBOUND.
> 
> WQ_PERCPU is included in ordered_flags after commit 69635d7f4b34 ("fs:
> WQ_PERCPU added to alloc_workqueue users") and WQ_UNBOUND is set in
> alloc_ordered_workqueue(), which btrfs_alloc_ordered_workqueue() calls.
> 
> Drop WQ_PERCPU from ordered_flags, as alloc_ordered_workqueue() notes
> that only WQ_FREEZABLE and WQ_MEM_RECLAIM are meaningful.
> 
> Fixes: 69635d7f4b34 ("fs: WQ_PERCPU added to alloc_workqueue users")
> Fixes: 21c05ca88a54 ("workqueue: Add warnings and ensure one among WQ_PERCPU or WQ_UNBOUND is present")
> Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx>

Reviewed-by: Breno Leitao <leitao@xxxxxxxxxx>

This will solve the following issue I am seeing in linux-next:

   workqueue: btrfs-qgroup-rescan uses both WQ_PERCPU and WQ_UNBOUND. Dropped WQ_PERCPU, keeping WQ_UNBOUND.