[RFC PATCH 07/10] clocksource/drivers/h8300_timer8: Remove pointless irq re-entrant safe code

From: Daniel Lezcano
Date: Sun Nov 08 2015 - 17:38:34 EST


The current code assumes the interrupt function is re-entrant.

That is not correct. An interrupt handler is never invoked concurrently. The
interrupt line is masked on all processors.

Remove the chewing flags in the code.

Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
---
drivers/clocksource/h8300_timer8.c | 15 ++++++---------
1 file changed, 6 insertions(+), 9 deletions(-)

diff --git a/drivers/clocksource/h8300_timer8.c b/drivers/clocksource/h8300_timer8.c
index 680f65b..ba219cf 100644
--- a/drivers/clocksource/h8300_timer8.c
+++ b/drivers/clocksource/h8300_timer8.c
@@ -24,8 +24,6 @@
#define TCORB 6
#define _8TCNT 8

-#define FLAG_SKIPEVENT (1 << 1)
-#define FLAG_IRQCONTEXT (1 << 2)
#define FLAG_STARTED (1 << 3)

#define SCALE 64
@@ -67,14 +65,13 @@ static irqreturn_t timer8_interrupt(int irq, void *dev_id)

ctrl_outb(ctrl_inb(p->mapbase + _8TCSR) & ~0x40,
p->mapbase + _8TCSR);
- p->flags |= FLAG_IRQCONTEXT;
+
ctrl_outw(p->tcora, p->mapbase + TCORA);
- if (!(p->flags & FLAG_SKIPEVENT)) {
- if (clockevent_state_oneshot(&p->ced))
- ctrl_outw(0x0000, p->mapbase + _8TCR);
- p->ced.event_handler(&p->ced);
- }
- p->flags &= ~(FLAG_SKIPEVENT | FLAG_IRQCONTEXT);
+
+ if (clockevent_state_oneshot(&p->ced))
+ ctrl_outw(0x0000, p->mapbase + _8TCR);
+
+ p->ced.event_handler(&p->ced);

return IRQ_HANDLED;
}
--
1.9.1

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