-----Original Message----- From: Thomas Gleixner [mailto:tglx@linutronix.de] Sent: Friday, January 29, 2021 8:55 AM To: Song Bao Hua (Barry Song) <song.bao.hua@hisilicon.com>; dmitry.torokhov@gmail.com; maz@kernel.org; gregkh@linuxfoundation.org; linux-input@vger.kernel.org; linux-kernel@vger.kernel.org Cc: linuxarm@openeuler.org; Song Bao Hua (Barry Song) <song.bao.hua@hisilicon.com> Subject: Re: [PATCH v3 01/12] genirq: add IRQF_NO_AUTOEN for request_irq
Barry,
On Fri, Jan 08 2021 at 11:39, Barry Song wrote:
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index ab8567f32501..2b28314e2572 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -1693,6 +1693,9 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) irqd_set(&desc->irq_data, IRQD_NO_BALANCING); }
+ if (new->flags & IRQF_NO_AUTOEN) + irq_settings_set_noautoen(desc);
If we move this to request time flags, then setting the noautoen bit on the irq descriptor is pretty pointless. See below.
I rather get rid of the irq_settings magic for NOAUTOEN completely.
Thanks for your comment, Thomas. Got this issue fixed in v4: https://lore.kernel.org/lkml/20210128223538.20272-1-song.bao.hua@hisilicon.c... btw, for those drivers which are using the first pattern: irq_set_status_flags(irq, IRQ_NOAUTOEN); request_irq(dev, irq...); Simply running "git grep IRQ_NOAUTOEN" will help figure where to fix. For those drivers which are using the second pattern: request_irq(dev, irq...); disable_irq(irq); I wrote a script as below: #!/bin/bash if [ $# != 1 -o ! -d $1 ] ; then echo "USAGE: $0 dir" exit 1; fi find $1 -iname "*.c" | while read i do if [ -d "$i" ]; then break fi irq=`grep -n -A 10 -E "request_irq|request_threaded_irq|request_any_context_irq" $i | grep disable_irq` if [ "$irq" != "" ]; then echo "$i":"$irq" fi done The script says there are more than 70 cases in 5.11-rc6. We are going to fix all of them after this one settles down. Thanks Barry
Thanks,
tglx --- --- a/include/linux/interrupt.h +++ b/include/linux/interrupt.h @@ -61,6 +61,8 @@ * interrupt handler after suspending interrupts. For system * wakeup devices users need to implement wakeup detection in * their interrupt handlers. + * IRQF_NO_AUTOEN - Don't enable IRQ automatically when users request it. Users + * will enable it explicitly by enable_irq() later. */ #define IRQF_SHARED 0x00000080 #define IRQF_PROBE_SHARED 0x00000100 @@ -74,6 +76,7 @@ #define IRQF_NO_THREAD 0x00010000 #define IRQF_EARLY_RESUME 0x00020000 #define IRQF_COND_SUSPEND 0x00040000 +#define IRQF_NO_AUTOEN 0x00080000
#define IRQF_TIMER (__IRQF_TIMER | IRQF_NO_SUSPEND | IRQF_NO_THREAD)
--- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -1693,7 +1693,8 @@ static int irqd_set(&desc->irq_data, IRQD_NO_BALANCING); }
- if (irq_settings_can_autoenable(desc)) { + if (!(new->flags & IRQF_NO_AUTOEN) && + irq_settings_can_autoenable(desc)) { irq_startup(desc, IRQ_RESEND, IRQ_START_COND); } else { /* @@ -2086,10 +2087,15 @@ int request_threaded_irq(unsigned int ir * which interrupt is which (messes up the interrupt freeing * logic etc). * + * Also shared interrupts do not go well with disabling auto enable. + * The sharing interrupt might request it while it's still disabled + * and then wait for interrupts forever. + * * Also IRQF_COND_SUSPEND only makes sense for shared interrupts and * it cannot be set along with IRQF_NO_SUSPEND. */ if (((irqflags & IRQF_SHARED) && !dev_id) || + ((irqflags & IRQF_SHARED) && (irqflags & IRQF_NO_AUTOEN)) || (!(irqflags & IRQF_SHARED) && (irqflags & IRQF_COND_SUSPEND)) || ((irqflags & IRQF_NO_SUSPEND) && (irqflags & IRQF_COND_SUSPEND))) return -EINVAL;