[PATCH 4/4] ide: don't enable/disable interrupts in force threaded-IRQ mode

From: Sebastian Andrzej Siewior
Date: Fri May 04 2018 - 10:25:31 EST


The interrupts are enabled/disabled so the interrupt handler can run
with enabled interrupts while serving the interrupt and not lose other
interrupts especially the timer tick.
If the system runs with force-threaded interrupts then there is no need
to enable the interrupts.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
---
drivers/ide/ide-iops.c | 13 +++++++++----
drivers/ide/ide-taskfile.c | 2 +-
kernel/irq/manage.c | 1 +
3 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/drivers/ide/ide-iops.c b/drivers/ide/ide-iops.c
index 210a0887dd29..d55e9ebd5628 100644
--- a/drivers/ide/ide-iops.c
+++ b/drivers/ide/ide-iops.c
@@ -108,6 +108,7 @@ int __ide_wait_stat(ide_drive_t *drive, u8 good, u8 bad,
ide_hwif_t *hwif = drive->hwif;
const struct ide_tp_ops *tp_ops = hwif->tp_ops;
unsigned long flags;
+ bool irqs_threaded = force_irqthreads;
int i;
u8 stat;

@@ -115,8 +116,10 @@ int __ide_wait_stat(ide_drive_t *drive, u8 good, u8 bad,
stat = tp_ops->read_status(hwif);

if (stat & ATA_BUSY) {
- local_save_flags(flags);
- local_irq_enable_in_hardirq();
+ if (!irqs_threaded) {
+ local_save_flags(flags);
+ local_irq_enable_in_hardirq();
+ }
timeout += jiffies;
while ((stat = tp_ops->read_status(hwif)) & ATA_BUSY) {
if (time_after(jiffies, timeout)) {
@@ -129,12 +132,14 @@ int __ide_wait_stat(ide_drive_t *drive, u8 good, u8 bad,
if ((stat & ATA_BUSY) == 0)
break;

- local_irq_restore(flags);
+ if (!irqs_threaded)
+ local_irq_restore(flags);
*rstat = stat;
return -EBUSY;
}
}
- local_irq_restore(flags);
+ if (!irqs_threaded)
+ local_irq_restore(flags);
}
/*
* Allow status to settle, then read it again.
diff --git a/drivers/ide/ide-taskfile.c b/drivers/ide/ide-taskfile.c
index 49f9b4739779..d42feeaebd36 100644
--- a/drivers/ide/ide-taskfile.c
+++ b/drivers/ide/ide-taskfile.c
@@ -405,7 +405,7 @@ static ide_startstop_t pre_task_out_intr(ide_drive_t *drive,
return startstop;
}

- if ((drive->dev_flags & IDE_DFLAG_UNMASK) == 0)
+ if (!force_irqthreads && (drive->dev_flags & IDE_DFLAG_UNMASK) == 0)
local_irq_disable();

ide_set_handler(drive, &task_pio_intr, WAIT_WORSTCASE);
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index e3336d904f64..4c2ef8084e32 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -24,6 +24,7 @@

#ifdef CONFIG_IRQ_FORCED_THREADING
__read_mostly bool force_irqthreads;
+EXPORT_SYMBOL_GPL(force_irqthreads);

static int __init setup_forced_irqthreads(char *arg)
{
--
2.17.0