* rudimentary ISR question
@ 2004-04-12 22:16 Steve Modica
0 siblings, 0 replies; 2+ messages in thread
From: Steve Modica @ 2004-04-12 22:16 UTC (permalink / raw)
To: netdev
Hi All,
I'm looking at the tg3.c driver in the 2.4.21 kernel and in the
_interrupt routing, the driver is calling spin_lock_irqsave.
Since it's guaranteed that the tg3 interrupt handler will be disabled
for the duration of the interrupt handler, why can't the driver simply
call spin_lock?
Steve
^ permalink raw reply [flat|nested] 2+ messages in thread
* Re: rudimentary ISR question
@ 2004-04-12 23:23 Krishna Kumar
0 siblings, 0 replies; 2+ messages in thread
From: Krishna Kumar @ 2004-04-12 23:23 UTC (permalink / raw)
To: Steve Modica; +Cc: netdev
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I think it is because the interrupt routine can be called as
dev->poll_controller()
and race with real interrupts.
- KK
|---------+---------------------------->
| | Steve Modica |
| | <modica@sgi.com> |
| | Sent by: |
| | netdev-bounce@oss|
| | .sgi.com |
| | |
| | |
| | 04/12/2004 03:16 |
| | PM |
| | |
|---------+---------------------------->
>-------------------------------------------------------------------------------------------------------------------------|
| |
| To: netdev@oss.sgi.com |
| cc: |
| Subject: rudimentary ISR question |
| |
>-------------------------------------------------------------------------------------------------------------------------|
Hi All,
I'm looking at the tg3.c driver in the 2.4.21 kernel and in the
_interrupt routing, the driver is calling spin_lock_irqsave.
Since it's guaranteed that the tg3 interrupt handler will be disabled
for the duration of the interrupt handler, why can't the driver simply
call spin_lock?
Steve
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