From: Marco Crivellari Date: Sat, 1 Nov 2025 16:31:13 +0000 (+0100) Subject: hfi1: WQ_PERCPU added to alloc_workqueue users X-Git-Tag: v6.19-rc1~130^2~53 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5f93287fa9d0db9bad0251e526dead4aed448288;p=thirdparty%2Fkernel%2Flinux.git hfi1: WQ_PERCPU added to alloc_workqueue users 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. 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. CC: Dennis Dalessandro Suggested-by: Tejun Heo Signed-off-by: Marco Crivellari Link: https://patch.msgid.link/20251101163121.78400-4-marco.crivellari@suse.com Signed-off-by: Leon Romanovsky --- diff --git a/drivers/infiniband/hw/hfi1/init.c b/drivers/infiniband/hw/hfi1/init.c index b35f92e7d865f..e4aef102dac0d 100644 --- a/drivers/infiniband/hw/hfi1/init.c +++ b/drivers/infiniband/hw/hfi1/init.c @@ -745,8 +745,8 @@ static int create_workqueues(struct hfi1_devdata *dd) ppd->hfi1_wq = alloc_workqueue( "hfi%d_%d", - WQ_SYSFS | WQ_HIGHPRI | WQ_CPU_INTENSIVE | - WQ_MEM_RECLAIM, + WQ_SYSFS | WQ_HIGHPRI | WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | + WQ_PERCPU, HFI1_MAX_ACTIVE_WORKQUEUE_ENTRIES, dd->unit, pidx); if (!ppd->hfi1_wq) diff --git a/drivers/infiniband/hw/hfi1/opfn.c b/drivers/infiniband/hw/hfi1/opfn.c index 370a5a8eaa716..6e0e3458d202f 100644 --- a/drivers/infiniband/hw/hfi1/opfn.c +++ b/drivers/infiniband/hw/hfi1/opfn.c @@ -305,8 +305,8 @@ void opfn_trigger_conn_request(struct rvt_qp *qp, u32 bth1) int opfn_init(void) { opfn_wq = alloc_workqueue("hfi_opfn", - WQ_SYSFS | WQ_HIGHPRI | WQ_CPU_INTENSIVE | - WQ_MEM_RECLAIM, + WQ_SYSFS | WQ_HIGHPRI | WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | + WQ_PERCPU, HFI1_MAX_ACTIVE_WORKQUEUE_ENTRIES); if (!opfn_wq) return -ENOMEM;