usb/hcd: remove unnecessary local_irq_save

Remove the use of local_irq_save() and IRQF_DISABLED, no longer needed since
interrupt handlers are always run with interrupts disabled on the
current CPU.

Tested successfully with 3.12.0-rc4 on my PC. Didn't find
any issue because of this change.

Signed-off-by: Michael Opdenacker <michael.opdenacker@free-electrons.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index 6ec8dda31118e8fdec4ef5cfea0eb2f755939f70..6bffb8c87bc9aaee98c2342b0f7a5a3c05c870b0 100644 (file)
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -2331,15 +2331,8 @@ EXPORT_SYMBOL_GPL(usb_bus_start_enum);
 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
 {
        struct usb_hcd          *hcd = __hcd;
-       unsigned long           flags;
        irqreturn_t             rc;
 
-       /* IRQF_DISABLED doesn't work correctly with shared IRQs
-        * when the first handler doesn't use it.  So let's just
-        * assume it's never used.
-        */
-       local_irq_save(flags);
-
        if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
                rc = IRQ_NONE;
        else if (hcd->driver->irq(hcd) == IRQ_NONE)
@@ -2347,7 +2340,6 @@ irqreturn_t usb_hcd_irq (int irq, void *__hcd)
        else
                rc = IRQ_HANDLED;
 
-       local_irq_restore(flags);
        return rc;
 }
 EXPORT_SYMBOL_GPL(usb_hcd_irq);
@@ -2554,13 +2546,6 @@ static int usb_hcd_request_irqs(struct usb_hcd *hcd,
 
        if (hcd->driver->irq) {
 
-               /* IRQF_DISABLED doesn't work as advertised when used together
-                * with IRQF_SHARED. As usb_hcd_irq() will always disable
-                * interrupts we can remove it here.
-                */
-               if (irqflags & IRQF_SHARED)
-                       irqflags &= ~IRQF_DISABLED;
-
                snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
                                hcd->driver->description, hcd->self.busnum);
                retval = request_irq(irqnum, &usb_hcd_irq, irqflags,