[PATCH resend] staging: rts5208: Remove unnecessary synchronize_irq() before free_irq()

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From	Lars-Peter Clausen <lars@metafoo.de>
Newsgroups	linux.kernel
Subject	[PATCH resend] staging: rts5208: Remove unnecessary synchronize_irq() before free_irq()
Date	Sat, 30 Jan 2016 15:50:01 +0100
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Calling synchronize_irq() right before free_irq() is quite useless. On one
hand the IRQ can easily fire again before free_irq() is entered, on the
other hand free_irq() itself calls synchronize_irq() internally (in a race
condition free way), before any state associated with the IRQ is freed.

Patch was generated using the following semantic patch:
// <smpl>
@@
expression irq;
@@
-synchronize_irq(irq);
 free_irq(irq, ...);
// </smpl>

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
---
 drivers/staging/rts5208/rtsx.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/staging/rts5208/rtsx.c b/drivers/staging/rts5208/rtsx.c
index 1fe8e3e..5dfcdfb 100644
--- a/drivers/staging/rts5208/rtsx.c
+++ b/drivers/staging/rts5208/rtsx.c
@@ -320,7 +320,6 @@ static int rtsx_suspend(struct pci_dev *pci, pm_message_t state)
 	rtsx_do_before_power_down(chip, PM_S3);
 
 	if (dev->irq >= 0) {
-		synchronize_irq(dev->irq);
 		free_irq(dev->irq, (void *)dev);
 		dev->irq = -1;
 	}
@@ -398,7 +397,6 @@ static void rtsx_shutdown(struct pci_dev *pci)
 	rtsx_do_before_power_down(chip, PM_S1);
 
 	if (dev->irq >= 0) {
-		synchronize_irq(dev->irq);
 		free_irq(dev->irq, (void *)dev);
 		dev->irq = -1;
 	}
-- 
2.1.4

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[PATCH resend] staging: rts5208: Remove unnecessary synchronize_irq() before free_irq() Lars-Peter Clausen <lars@metafoo.de> - 2016-01-30 15:50 +0100

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