[PATCH 06/12] mfd: twl4030-irq: micro-optimization on IRQ handler
From: Benoit Cousson <hidden>
Date: 2012-03-02 16:50:18
Also in:
linux-omap
Subsystem:
multifunction devices (mfd), omap2+ support, the rest · Maintainers:
Lee Jones, Aaro Koskinen, Andreas Kemnade, Kevin Hilman, Roger Quadros, Tony Lindgren, Linus Torvalds
From: Felipe Balbi <redacted> __ffs() will be far faster than the for loop used. Signed-off-by: Felipe Balbi <redacted> --- drivers/mfd/twl4030-irq.c | 14 +++++++------- 1 files changed, 7 insertions(+), 7 deletions(-)
diff --git a/drivers/mfd/twl4030-irq.c b/drivers/mfd/twl4030-irq.c
index faf3318..e6dc8f9 100644
--- a/drivers/mfd/twl4030-irq.c
+++ b/drivers/mfd/twl4030-irq.c@@ -293,7 +293,6 @@ static unsigned twl4030_irq_base; */ static irqreturn_t handle_twl4030_pih(int irq, void *devid) { - int module_irq; irqreturn_t ret; u8 pih_isr;
@@ -304,12 +303,13 @@ static irqreturn_t handle_twl4030_pih(int irq, void *devid) return IRQ_NONE; } - /* these handlers deal with the relevant SIH irq status */ - for (module_irq = twl4030_irq_base; - pih_isr; - pih_isr >>= 1, module_irq++) { - if (pih_isr & 0x1) - handle_nested_irq(module_irq); + while (pih_isr) { + unsigned long pending = __ffs(pih_isr); + unsigned int irq; + + pih_isr &= ~BIT(pending); + irq = pending + twl4030_irq_base; + handle_nested_irq(irq); } return IRQ_HANDLED;
--
1.7.0.4