linux-kernel - [PATCH 1/5] RDMA/core: RDMA/mlx5: replace use of system_unbound_wq with system_dfl

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20251101163121.78400-2-marco.crivellari@suse.com>
Date: Sat,  1 Nov 2025 17:31:11 +0100
From: Marco Crivellari <marco.crivellari@...e.com>
To: linux-kernel@...r.kernel.org,
	linux-rdma@...r.kernel.org
Cc: Tejun Heo <tj@...nel.org>,
	Lai Jiangshan <jiangshanlai@...il.com>,
	Frederic Weisbecker <frederic@...nel.org>,
	Sebastian Andrzej Siewior <bigeasy@...utronix.de>,
	Marco Crivellari <marco.crivellari@...e.com>,
	Michal Hocko <mhocko@...e.com>,
	Jason Gunthorpe <jgg@...pe.ca>,
	Leon Romanovsky <leon@...nel.org>
Subject: [PATCH 1/5] RDMA/core: RDMA/mlx5: replace use of system_unbound_wq with system_dfl_wq

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 consistency cannot be addressed without refactoring the API.

system_unbound_wq should be the default workqueue so as not to enforce
locality constraints for random work whenever it's not required.

Adding system_dfl_wq to encourage its use when unbound work should be used.

The old system_unbound_wq will be kept for a few release cycles.

Suggested-by: Tejun Heo <tj@...nel.org>
Signed-off-by: Marco Crivellari <marco.crivellari@...e.com>
---
 drivers/infiniband/core/ucma.c   | 2 +-
 drivers/infiniband/hw/mlx5/odp.c | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c
index f86ece701db6..ec3be65a2b88 100644
--- a/drivers/infiniband/core/ucma.c
+++ b/drivers/infiniband/core/ucma.c
@@ -366,7 +366,7 @@ static int ucma_event_handler(struct rdma_cm_id *cm_id,
 	if (event->event == RDMA_CM_EVENT_DEVICE_REMOVAL) {
 		xa_lock(&ctx_table);
 		if (xa_load(&ctx_table, ctx->id) == ctx)
-			queue_work(system_unbound_wq, &ctx->close_work);
+			queue_work(system_dfl_wq, &ctx->close_work);
 		xa_unlock(&ctx_table);
 	}
 	return 0;
diff --git a/drivers/infiniband/hw/mlx5/odp.c b/drivers/infiniband/hw/mlx5/odp.c
index 0e8ae85af5a6..6441abdf1f3b 100644
--- a/drivers/infiniband/hw/mlx5/odp.c
+++ b/drivers/infiniband/hw/mlx5/odp.c
@@ -265,7 +265,7 @@ static void destroy_unused_implicit_child_mr(struct mlx5_ib_mr *mr)
 
 	/* Freeing a MR is a sleeping operation, so bounce to a work queue */
 	INIT_WORK(&mr->odp_destroy.work, free_implicit_child_mr_work);
-	queue_work(system_unbound_wq, &mr->odp_destroy.work);
+	queue_work(system_dfl_wq, &mr->odp_destroy.work);
 }
 
 static bool mlx5_ib_invalidate_range(struct mmu_interval_notifier *mni,
@@ -2093,6 +2093,6 @@ int mlx5_ib_advise_mr_prefetch(struct ib_pd *pd,
 		destroy_prefetch_work(work);
 		return rc;
 	}
-	queue_work(system_unbound_wq, &work->work);
+	queue_work(system_dfl_wq, &work->work);
 	return 0;
 }
-- 
2.51.0