Re: [PATCH] usb: Remove redundant 'flush_workqueue()' calls

From: Peter Chen
Date: Sat Nov 13 2021 - 07:25:56 EST


On 21-11-12 17:30:16, Christophe JAILLET wrote:
> 'destroy_workqueue()' already drains the queue before destroying it, so
> there is no need to flush it explicitly.
>
> Remove the redundant 'flush_workqueue()' calls.
>
> This was generated with coccinelle:
>
> @@
> expression E;
> @@
> - flush_workqueue(E);
> destroy_workqueue(E);
>
> Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
> ---
> drivers/usb/chipidea/otg.c | 5 ++---

Acked-by: Peter Chen <peter.chen@xxxxxxxxx> # for chipidea part
> drivers/usb/gadget/udc/mv_udc_core.c | 4 +---
> drivers/usb/host/u132-hcd.c | 1 -
> drivers/usb/phy/phy-mv-usb.c | 5 +----
> drivers/usb/usbip/usbip_event.c | 1 -
> 5 files changed, 4 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/usb/chipidea/otg.c b/drivers/usb/chipidea/otg.c
> index 8dd59282827b..7b53274ef966 100644
> --- a/drivers/usb/chipidea/otg.c
> +++ b/drivers/usb/chipidea/otg.c
> @@ -255,10 +255,9 @@ int ci_hdrc_otg_init(struct ci_hdrc *ci)
> */
> void ci_hdrc_otg_destroy(struct ci_hdrc *ci)
> {
> - if (ci->wq) {
> - flush_workqueue(ci->wq);
> + if (ci->wq)
> destroy_workqueue(ci->wq);
> - }
> +
> /* Disable all OTG irq and clear status */
> hw_write_otgsc(ci, OTGSC_INT_EN_BITS | OTGSC_INT_STATUS_BITS,
> OTGSC_INT_STATUS_BITS);
> diff --git a/drivers/usb/gadget/udc/mv_udc_core.c b/drivers/usb/gadget/udc/mv_udc_core.c
> index 7f24ce400b59..b6d34dda028b 100644
> --- a/drivers/usb/gadget/udc/mv_udc_core.c
> +++ b/drivers/usb/gadget/udc/mv_udc_core.c
> @@ -2084,10 +2084,8 @@ static int mv_udc_remove(struct platform_device *pdev)
>
> usb_del_gadget_udc(&udc->gadget);
>
> - if (udc->qwork) {
> - flush_workqueue(udc->qwork);
> + if (udc->qwork)
> destroy_workqueue(udc->qwork);
> - }
>
> /* free memory allocated in probe */
> dma_pool_destroy(udc->dtd_pool);
> diff --git a/drivers/usb/host/u132-hcd.c b/drivers/usb/host/u132-hcd.c
> index ae882d76612b..d879d6af5710 100644
> --- a/drivers/usb/host/u132-hcd.c
> +++ b/drivers/usb/host/u132-hcd.c
> @@ -3211,7 +3211,6 @@ static void __exit u132_hcd_exit(void)
> platform_driver_unregister(&u132_platform_driver);
> printk(KERN_INFO "u132-hcd driver deregistered\n");
> wait_event(u132_hcd_wait, u132_instances == 0);
> - flush_workqueue(workqueue);
> destroy_workqueue(workqueue);
> }
>
> diff --git a/drivers/usb/phy/phy-mv-usb.c b/drivers/usb/phy/phy-mv-usb.c
> index 576d925af77c..86503b7d695c 100644
> --- a/drivers/usb/phy/phy-mv-usb.c
> +++ b/drivers/usb/phy/phy-mv-usb.c
> @@ -648,10 +648,8 @@ static int mv_otg_remove(struct platform_device *pdev)
> {
> struct mv_otg *mvotg = platform_get_drvdata(pdev);
>
> - if (mvotg->qwork) {
> - flush_workqueue(mvotg->qwork);
> + if (mvotg->qwork)
> destroy_workqueue(mvotg->qwork);
> - }
>
> mv_otg_disable(mvotg);
>
> @@ -825,7 +823,6 @@ static int mv_otg_probe(struct platform_device *pdev)
> err_disable_clk:
> mv_otg_disable_internal(mvotg);
> err_destroy_workqueue:
> - flush_workqueue(mvotg->qwork);
> destroy_workqueue(mvotg->qwork);
>
> return retval;
> diff --git a/drivers/usb/usbip/usbip_event.c b/drivers/usb/usbip/usbip_event.c
> index 086ca76dd053..26513540bcdb 100644
> --- a/drivers/usb/usbip/usbip_event.c
> +++ b/drivers/usb/usbip/usbip_event.c
> @@ -137,7 +137,6 @@ int usbip_init_eh(void)
>
> void usbip_finish_eh(void)
> {
> - flush_workqueue(usbip_queue);
> destroy_workqueue(usbip_queue);
> usbip_queue = NULL;
> }
> --
> 2.30.2
>

--

Thanks,
Peter Chen