From 84150ef06f897cc2c03456edb5ad5c2a03faf9f1 Mon Sep 17 00:00:00 2001 From: Marco Crivellari Date: Tue, 4 Nov 2025 12:08:08 +0100 Subject: [PATCH] scsi: lpfc: WQ_PERCPU added to alloc_workqueue() users MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Currently if a user enqueue a work item using schedule_delayed_work() the used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies to schedule_work() that is using system_wq and queue_work(), that makes use again of WORK_CPU_UNBOUND. This lack of consistentcy cannot be addressed without refactoring the API. alloc_workqueue() treats all queues as per-CPU by default, while unbound workqueues must opt-in via WQ_UNBOUND. This default is suboptimal: most workloads benefit from unbound queues, allowing the scheduler to place worker threads where they’re needed and reducing noise when CPUs are isolated. This change adds a new WQ_PERCPU flag to explicitly request alloc_workqueue() to be per-cpu when WQ_UNBOUND has not been specified. This patch continues the effort to refactor worqueue APIs, which has begun with the change introducing new workqueues and a new alloc_workqueue flag: commit 128ea9f6ccfb ("workqueue: Add system_percpu_wq and system_dfl_wq") commit 930c2ea566af ("workqueue: Add new WQ_PERCPU flag") With the introduction of the WQ_PERCPU flag (equivalent to !WQ_UNBOUND), any alloc_workqueue() caller that doesn’t explicitly specify WQ_UNBOUND must now use WQ_PERCPU. Once migration is complete, WQ_UNBOUND can be removed and unbound will become the implicit default. Suggested-by: Tejun Heo Signed-off-by: Marco Crivellari Reviewed-by: Justin Tee Link: https://patch.msgid.link/20251104110808.123424-1-marco.crivellari@suse.com Signed-off-by: Martin K. Petersen --- drivers/scsi/lpfc/lpfc_init.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/scsi/lpfc/lpfc_init.c b/drivers/scsi/lpfc/lpfc_init.c index f206267d9ecd..45d43e9c5827 100644 --- a/drivers/scsi/lpfc/lpfc_init.c +++ b/drivers/scsi/lpfc/lpfc_init.c @@ -7950,7 +7950,7 @@ lpfc_sli4_driver_resource_setup(struct lpfc_hba *phba) /* Allocate all driver workqueues here */ /* The lpfc_wq workqueue for deferred irq use */ - phba->wq = alloc_workqueue("lpfc_wq", WQ_MEM_RECLAIM, 0); + phba->wq = alloc_workqueue("lpfc_wq", WQ_MEM_RECLAIM | WQ_PERCPU, 0); if (!phba->wq) return -ENOMEM;