Re: [PATCH v4 4/5] Coresight: Add Coresight TMC Control Unit driver

From: Markus Elfring
Date: Wed Aug 28 2024 - 13:53:03 EST



> +++ b/drivers/hwtracing/coresight/coresight-ctcu.c
> @@ -0,0 +1,292 @@

> +static int __ctcu_set_etr_traceid(struct coresight_device *csdev,
> + u8 traceid,
> + int port_num,
> + bool enable)
> +{

> + spin_lock_irqsave(&drvdata->spin_lock, flags);
> + CS_UNLOCK(drvdata->base);

> + CS_LOCK(drvdata->base);
> + spin_unlock_irqrestore(&drvdata->spin_lock, flags);
> +
> + return 0;
> +}


Under which circumstances would you become interested to apply a statement
like “guard(spinlock_irqsave)(&drvdata->spin_lock);”?
https://elixir.bootlin.com/linux/v6.11-rc5/source/include/linux/spinlock.h#L572

Regards,
Markus