On Wed, Mar 27, 2024 at 04:03:11PM +0000, Allen Pais wrote: > The only generic interface to execute asynchronously in the BH context is > tasklet; however, it's marked deprecated and has some design flaws. To > replace tasklets, BH workqueue support was recently added. A BH workqueue > behaves similarly to regular workqueues except that the queued work items > are executed in the BH context. > > This patch converts drivers/infiniband/* from tasklet to BH workqueue. I think you mean drivers/char/ipmi/* here. I believe that work queues items are execute single-threaded for a work queue, so this should be good. I need to test this, though. It may be that an IPMI device can have its own work queue; it may not be important to run it in bh context. -corey > > Based on the work done by Tejun Heo <tj@xxxxxxxxxx> > Branch: https://git.kernel.org/pub/scm/linux/kernel/git/tj/wq.git for-6.10 > > Signed-off-by: Allen Pais <allen.lkml@xxxxxxxxx> > --- > drivers/char/ipmi/ipmi_msghandler.c | 30 ++++++++++++++--------------- > 1 file changed, 15 insertions(+), 15 deletions(-) > > diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c > index b0eedc4595b3..fce2a2dbdc82 100644 > --- a/drivers/char/ipmi/ipmi_msghandler.c > +++ b/drivers/char/ipmi/ipmi_msghandler.c > @@ -36,12 +36,13 @@ > #include <linux/nospec.h> > #include <linux/vmalloc.h> > #include <linux/delay.h> > +#include <linux/workqueue.h> > > #define IPMI_DRIVER_VERSION "39.2" > > static struct ipmi_recv_msg *ipmi_alloc_recv_msg(void); > static int ipmi_init_msghandler(void); > -static void smi_recv_tasklet(struct tasklet_struct *t); > +static void smi_recv_work(struct work_struct *t); > static void handle_new_recv_msgs(struct ipmi_smi *intf); > static void need_waiter(struct ipmi_smi *intf); > static int handle_one_recv_msg(struct ipmi_smi *intf, > @@ -498,13 +499,13 @@ struct ipmi_smi { > /* > * Messages queued for delivery. If delivery fails (out of memory > * for instance), They will stay in here to be processed later in a > - * periodic timer interrupt. The tasklet is for handling received > + * periodic timer interrupt. The work is for handling received > * messages directly from the handler. > */ > spinlock_t waiting_rcv_msgs_lock; > struct list_head waiting_rcv_msgs; > atomic_t watchdog_pretimeouts_to_deliver; > - struct tasklet_struct recv_tasklet; > + struct work_struct recv_work; > > spinlock_t xmit_msgs_lock; > struct list_head xmit_msgs; > @@ -704,7 +705,7 @@ static void clean_up_interface_data(struct ipmi_smi *intf) > struct cmd_rcvr *rcvr, *rcvr2; > struct list_head list; > > - tasklet_kill(&intf->recv_tasklet); > + cancel_work_sync(&intf->recv_work); > > free_smi_msg_list(&intf->waiting_rcv_msgs); > free_recv_msg_list(&intf->waiting_events); > @@ -1319,7 +1320,7 @@ static void free_user(struct kref *ref) > { > struct ipmi_user *user = container_of(ref, struct ipmi_user, refcount); > > - /* SRCU cleanup must happen in task context. */ > + /* SRCU cleanup must happen in work context. */ > queue_work(remove_work_wq, &user->remove_work); > } > > @@ -3605,8 +3606,7 @@ int ipmi_add_smi(struct module *owner, > intf->curr_seq = 0; > spin_lock_init(&intf->waiting_rcv_msgs_lock); > INIT_LIST_HEAD(&intf->waiting_rcv_msgs); > - tasklet_setup(&intf->recv_tasklet, > - smi_recv_tasklet); > + INIT_WORK(&intf->recv_work, smi_recv_work); > atomic_set(&intf->watchdog_pretimeouts_to_deliver, 0); > spin_lock_init(&intf->xmit_msgs_lock); > INIT_LIST_HEAD(&intf->xmit_msgs); > @@ -4779,7 +4779,7 @@ static void handle_new_recv_msgs(struct ipmi_smi *intf) > * To preserve message order, quit if we > * can't handle a message. Add the message > * back at the head, this is safe because this > - * tasklet is the only thing that pulls the > + * work is the only thing that pulls the > * messages. > */ > list_add(&smi_msg->link, &intf->waiting_rcv_msgs); > @@ -4812,10 +4812,10 @@ static void handle_new_recv_msgs(struct ipmi_smi *intf) > } > } > > -static void smi_recv_tasklet(struct tasklet_struct *t) > +static void smi_recv_work(struct work_struct *t) > { > unsigned long flags = 0; /* keep us warning-free. */ > - struct ipmi_smi *intf = from_tasklet(intf, t, recv_tasklet); > + struct ipmi_smi *intf = from_work(intf, t, recv_work); > int run_to_completion = intf->run_to_completion; > struct ipmi_smi_msg *newmsg = NULL; > > @@ -4866,7 +4866,7 @@ void ipmi_smi_msg_received(struct ipmi_smi *intf, > > /* > * To preserve message order, we keep a queue and deliver from > - * a tasklet. > + * a work. > */ > if (!run_to_completion) > spin_lock_irqsave(&intf->waiting_rcv_msgs_lock, flags); > @@ -4887,9 +4887,9 @@ void ipmi_smi_msg_received(struct ipmi_smi *intf, > spin_unlock_irqrestore(&intf->xmit_msgs_lock, flags); > > if (run_to_completion) > - smi_recv_tasklet(&intf->recv_tasklet); > + smi_recv_work(&intf->recv_work); > else > - tasklet_schedule(&intf->recv_tasklet); > + queue_work(system_bh_wq, &intf->recv_work); > } > EXPORT_SYMBOL(ipmi_smi_msg_received); > > @@ -4899,7 +4899,7 @@ void ipmi_smi_watchdog_pretimeout(struct ipmi_smi *intf) > return; > > atomic_set(&intf->watchdog_pretimeouts_to_deliver, 1); > - tasklet_schedule(&intf->recv_tasklet); > + queue_work(system_bh_wq, &intf->recv_work); > } > EXPORT_SYMBOL(ipmi_smi_watchdog_pretimeout); > > @@ -5068,7 +5068,7 @@ static bool ipmi_timeout_handler(struct ipmi_smi *intf, > flags); > } > > - tasklet_schedule(&intf->recv_tasklet); > + queue_work(system_bh_wq, &intf->recv_work); > > return need_timer; > } > -- > 2.17.1 > >