On 4/23/07, Mukund JB. <mukundjb@xxxxxxxxxxxxxxxxxxxxx> wrote:
> On 4/23/07, Guennadi Liakhovetski <gl@xxxxxxxxx> wrote: > > On Mon, 23 Apr 2007, pradeep singh wrote: > > > > > On 4/23/07, Guennadi Liakhovetski <gl@xxxxxxxxx> wrote: > > > > > > > > This cannot be true. Lost interrupts are bad, and you'd get them all > the > > > > time, so, nothing would work. > > > Right.That clears a lot of doubts. > > > But all the interrupts in the mean time are taken care by the PIC only > > > AFAIK.Am i right? The moment CPU is ready to accept the interrupts > > > again on the line, the inetrrupts are served. > > > > Yes, as long as these are different interrupts. > Means the interrupt disabled using local_irq_save() if received in > this period of time will be kind of buffered by the PIC only and only > will be delivered to the CPU the moment interrupt is enabled > again.Right? I am a little confused.Can you please help? AFAIK When you disable using local_irq_save(), the PIC interrupt lines going to the CPU will be copied to the flags variable and all interrupts on that CPU will be disabled.
Only the maskable interrupts i guess.
When you again use restore call, the flags variables which was earlier saved in call to local_irq_save() will be restored.
Yes, agreed.
> > What would happen if the same interrupt which was disabled using > local_irq_save() is recieved again before local_irq_restore()? > It will be buffered at the PIC only, right? Or is it that it will be > served?Just like any interrupt on other lines? Lets say you were trying to hold Interrupt 9, and even if you receive any multiple interrupts before call to local_irq_restore(), the old value saved at local_irq_save() call will only be restored. So, NO new PIC vales will be reflected on the CPU after call to local_irq_restore().
So you are saying they are lost??? Thanks ~psr
> Thank you > ~psr > > > > > > Is my limited knowledge correct Guennadi? > > > > Very few people have unlimited knowledge...:-) > > > > Thanks > > Guennadi > > --------------------------------- > > Guennadi Liakhovetski, Ph.D. > > DSA Daten- und Systemtechnik GmbH > > Pascalstr. 28 > > D-52076 Aachen > > Germany > > > > > -- > play the game > > -- > To unsubscribe from this list: send an email with > "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx > Please read the FAQ at http://kernelnewbies.org/FAQ
-- play the game -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
