Commit 3a3e2b83 authored by Sudeep Holla's avatar Sudeep Holla
Browse files

firmware: arm_ffa: Avoid queuing work when running on the worker queue 

Currently notif_pcpu_irq_work_fn() may get queued from the work that is
already running on the 'notif_pcpu_wq' workqueue. This may add
unnecessary delays and could be avoided if the work is called directly
instead.

This change removes queuing of the work when already running on the
'notif_pcpu_wq' workqueue thereby removing any possible delays in that
path.

Link: https://lore.kernel.org/r/20240424131640.706870-1-sudeep.holla@arm.com


Signed-off-by: default avatarSudeep Holla <sudeep.holla@arm.com>
parent ddfade88

drivers/firmware/arm_ffa/driver.c

+14 −5
Original line number Diff line number Diff line
@@ -1146,7 +1146,7 @@ static void handle_notif_callbacks(u64 bitmap, enum notify_type type) 
	}

}



static void notif_pcpu_irq_work_fn(struct work_struct *work)

static void notif_get_and_handle(void *unused)

{

	int rc;

	struct ffa_notify_bitmaps bitmaps;
@@ -1169,10 +1169,17 @@ ffa_self_notif_handle(u16 vcpu, bool is_per_vcpu, void *cb_data) 
	struct ffa_drv_info *info = cb_data;



	if (!is_per_vcpu)

		notif_pcpu_irq_work_fn(&info->notif_pcpu_work);

		notif_get_and_handle(info);

	else

		queue_work_on(vcpu, info->notif_pcpu_wq,

			      &info->notif_pcpu_work);

		smp_call_function_single(vcpu, notif_get_and_handle, info, 0);

}



static void notif_pcpu_irq_work_fn(struct work_struct *work)

{

	struct ffa_drv_info *info = container_of(work, struct ffa_drv_info,

						 notif_pcpu_work);



	ffa_self_notif_handle(smp_processor_id(), true, info);

}



static const struct ffa_info_ops ffa_drv_info_ops = {
@@ -1345,8 +1352,10 @@ static irqreturn_t ffa_sched_recv_irq_handler(int irq, void *irq_data) 
static irqreturn_t notif_pend_irq_handler(int irq, void *irq_data)

{

	struct ffa_pcpu_irq *pcpu = irq_data;

	struct ffa_drv_info *info = pcpu->info;



	ffa_self_notif_handle(smp_processor_id(), true, pcpu->info);

	queue_work_on(smp_processor_id(), info->notif_pcpu_wq,

		      &info->notif_pcpu_work);



	return IRQ_HANDLED;

}