-----Original Message-----
From: Thomas Gleixner [mailto:<redacted>]
Sent: Friday, January 29, 2021 8:55 AM
To: Song Bao Hua (Barry Song) <redacted>;
dmitry.torokhov@gmail.com; maz@kernel.org; gregkh@linuxfoundation.org;
linux-input@vger.kernel.org; linux-kernel@vger.kernel.org
Cc: <redacted>; Song Bao Hua (Barry Song)
[off-list ref]
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:
quoted
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)
quoted
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.com/ (local)
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
quoted hunk ↗ jump to hunk
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;