linux/drivers/scsi/qedi
Marco Crivellari f60b8957d8 scsi: qedi: Add WQ_PERCPU to alloc_workqueue() users
Currently if a user enqueues 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.

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 continues the effort to refactor workqueue APIs, which began with
the introduction of new workqueues and a new alloc_workqueue flag in:

commit 128ea9f6cc ("workqueue: Add system_percpu_wq and system_dfl_wq")
commit 930c2ea566 ("workqueue: Add new WQ_PERCPU flag")

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.

Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Marco Crivellari <marco.crivellari@suse.com>
Link: https://patch.msgid.link/20251107151618.281250-1-marco.crivellari@suse.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
History 2025-11-12 21:28:26 -05:00
..
Kconfig treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
Makefile treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
qedi.h scsi: qedi: Fix cleanup session block/unblock use 2021-06-02 01:28:23 -04:00
qedi_dbg.c scsi: qedi: Remove unused sysfs functions 2025-04-21 21:51:08 -04:00
qedi_dbg.h scsi: qedi: Remove unused sysfs functions 2025-04-21 21:51:08 -04:00
qedi_debugfs.c scsi: qedi: Fix crash while reading debugfs attribute 2024-04-24 21:09:08 -04:00
qedi_fw.c SCSI misc on 20220324 2022-03-24 19:37:53 -07:00
qedi_fw_api.c qed: Remove e4_ and _e4 from FW HSI 2021-10-04 12:55:48 +01:00
qedi_fw_iscsi.h qed: Remove e4_ and _e4 from FW HSI 2021-10-04 12:55:48 +01:00
qedi_fw_scsi.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 440 2019-06-05 17:37:17 +02:00
qedi_gbl.h scsi: qedi: Remove unused qedi_get_proto_itt() 2025-04-21 21:51:09 -04:00
qedi_hsi.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 440 2019-06-05 17:37:17 +02:00
qedi_iscsi.c scsi: iscsi: Declare SCSI host template const 2023-03-24 19:19:57 -04:00
qedi_iscsi.h scsi: qedi: Fix cmd_cleanup_cmpl counter mismatch issue 2021-12-06 22:00:54 -05:00
qedi_main.c scsi: qedi: Add WQ_PERCPU to alloc_workqueue() users 2025-11-12 21:28:26 -05:00
qedi_nvm_iscsi_cfg.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 440 2019-06-05 17:37:17 +02:00
qedi_sysfs.c scsi: qedi: Switch to attribute groups 2021-10-16 21:45:58 -04:00
qedi_version.h SCSI fixes on 20190622 2019-06-22 09:39:03 -07:00