From 60b4c9d5c6feaf6020a424b05ca7e0c6bebe7b76 Mon Sep 17 00:00:00 2001 From: Davidlohr Bueso Date: Tue, 12 Jan 2021 19:15:37 -0800 Subject: [PATCH] usb/c67x00: Replace tasklet with work Tasklets have long been deprecated as being too heavy on the system by running in irq context - and this is not a performance critical path. If a higher priority process wants to run, it must wait for the tasklet to finish before doing so. c67x00_do_work() will now run in process context and have further concurrency (tasklets being serialized among themselves), but this is done holding the c67x00->lock, so it should be fine. Furthermore, this patch fixes the usage of the lock in the callback as otherwise it would need to be irq-safe. Signed-off-by: Davidlohr Bueso Link: https://lore.kernel.org/r/20210113031537.79859-1-dave@stgolabs.net Signed-off-by: Greg Kroah-Hartman --- drivers/usb/c67x00/c67x00-hcd.h | 2 +- drivers/usb/c67x00/c67x00-sched.c | 12 +++++++----- 2 files changed, 8 insertions(+), 6 deletions(-) diff --git a/drivers/usb/c67x00/c67x00-hcd.h b/drivers/usb/c67x00/c67x00-hcd.h index 6b6b04a..6332a6b 100644 --- a/drivers/usb/c67x00/c67x00-hcd.h +++ b/drivers/usb/c67x00/c67x00-hcd.h @@ -76,7 +76,7 @@ struct c67x00_hcd { u16 next_td_addr; u16 next_buf_addr; - struct tasklet_struct tasklet; + struct work_struct work; struct completion endpoint_disable; diff --git a/drivers/usb/c67x00/c67x00-sched.c b/drivers/usb/c67x00/c67x00-sched.c index e65f1a0..c7d3e90 100644 --- a/drivers/usb/c67x00/c67x00-sched.c +++ b/drivers/usb/c67x00/c67x00-sched.c @@ -1123,24 +1123,26 @@ static void c67x00_do_work(struct c67x00_hcd *c67x00) /* -------------------------------------------------------------------------- */ -static void c67x00_sched_tasklet(struct tasklet_struct *t) +static void c67x00_sched_work(struct work_struct *work) { - struct c67x00_hcd *c67x00 = from_tasklet(c67x00, t, tasklet); + struct c67x00_hcd *c67x00; + + c67x00 = container_of(work, struct c67x00_hcd, work); c67x00_do_work(c67x00); } void c67x00_sched_kick(struct c67x00_hcd *c67x00) { - tasklet_hi_schedule(&c67x00->tasklet); + queue_work(system_highpri_wq, &c67x00->work); } int c67x00_sched_start_scheduler(struct c67x00_hcd *c67x00) { - tasklet_setup(&c67x00->tasklet, c67x00_sched_tasklet); + INIT_WORK(&c67x00->work, c67x00_sched_work); return 0; } void c67x00_sched_stop_scheduler(struct c67x00_hcd *c67x00) { - tasklet_kill(&c67x00->tasklet); + cancel_work_sync(&c67x00->work); } -- 2.7.4