patches/ide-don-t-enable-disable-interrupts-in-force-threade.patch

From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Thu, 19 Apr 2018 11:22:55 +0200
Subject: [PATCH] ide: don't enable/disable interrupts in force threaded-IRQ
 mode

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@linutronix.de>
---
 drivers/ide/ide-iops.c     |   13 +++++++++----
 drivers/ide/ide-taskfile.c |    2 +-
 kernel/irq/manage.c        |    1 +
 3 files changed, 11 insertions(+), 5 deletions(-)

--- a/drivers/ide/ide-iops.c
+++ b/drivers/ide/ide-iops.c
@@ -108,6 +108,7 @@ int __ide_wait_stat(ide_drive_t *drive,
 	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,
 	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,
 				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.
--- a/drivers/ide/ide-taskfile.c
+++ b/drivers/ide/ide-taskfile.c
@@ -405,7 +405,7 @@ static ide_startstop_t pre_task_out_intr
 		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);
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -25,6 +25,7 @@
 
 #ifdef CONFIG_IRQ_FORCED_THREADING
 __read_mostly bool force_irqthreads;
+EXPORT_SYMBOL_GPL(force_irqthreads);
 
 static int __init setup_forced_irqthreads(char *arg)
 {