2005-09-05 13:34:04

by mandy london

[permalink] [raw]
Subject: the difference between irq save and the irq disable ?

in my mind, irq save only store the conditions of that time , and the
following code can access the shared region and change it ,so modify
irq states .

while , disable irq keeps the states of interrupt unchangable .

but , I have no knowlege of the difference between code in irq save
and irq restore and in irq disable and irq enable ?

whethe the former can be interrupted and the later not ? only this ?


2005-09-06 06:47:45

by Tushar Adeshara

[permalink] [raw]
Subject: Re: the difference between irq save and the irq disable ?

On 9/5/05, mandy london <[email protected]> wrote:
> in my mind, irq save only store the conditions of that time , and the
> following code can access the shared region and change it ,so modify
> irq states .
>
> while , disable irq keeps the states of interrupt unchangable .
>
> but , I have no knowlege of the difference between code in irq save
> and irq restore and in irq disable and irq enable ?
>
> whethe the former can be interrupted and the later not ? only this ?

Have a look at Documentaion/cli-sti-removal.txt. As per that,
irq_enable will enable all irqs and irq_restore will bring irq status
to the one it was
before irq_save.
And as per my knowledge, non are
interruptible except case of RT.

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--
Regards,
Tushar
--------------------
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