On Thu, Jul 4, 2013 at 3:19 PM, Raj Ravi <mekaviraj@xxxxxxxxx> wrote: > Thanks Anish. > > As for local_irq_save and raw_local_irq_save, it seems > local_irq_save - called at many different places while raw_local_irq_save is > called in fewer places. > > local_irq_save - does not disable Hardware > interrupts. > Whereas,raw_local_irq_save - does DISABLE hardware interrupts. > > As per code, raw_local_irq_save is related with timer interrupts. > Please provide your insights on this. http://lxr.free-electrons.com/source/include/linux/irqflags.h#L61 read this please. > > Also, in local_irq_save - how exactly disabling interrupts is achieved ( in > spite of " NOT DISABLING " hardware interrupts) ? > > > > > > On Thu, Jul 4, 2013 at 2:45 PM, anish singh <anish198519851985@xxxxxxxxx> > wrote: >> >> On Thu, Jul 4, 2013 at 1:55 PM, Raj Ravi <mekaviraj@xxxxxxxxx> wrote: >> > Hi, >> > >> > Please let me know the difference between >> > local_irq_save and raw_local_irq_save ? >> >> did you check who calls this raw_local_irq_save? >> similarly who calls local_irq_save? >> finding out these will answer your questions >> > At which situation one should use raw_local_irq_save? >> > >> > >> > Also, I read "flags" is where interrupt state is saved while disabling >> > interrupts in local cpu (for local_irq_save). >> > >> > What EXACTLY this flags contains? What do you mean by interrupt state >> > here? >> >> interrupt state meaning: which all interrupts are enabled or disabled at >> this >> instant.If a particular interrupt was enabled at that instant then we >> don't >> do any thing with our locking mechanism which causes it be be disabled. >> What we are doing with those flags is nothing but maintaining the state. >> > >> > Thanks! >> > Kavi >> > >> > _______________________________________________ >> > Kernelnewbies mailing list >> > Kernelnewbies@xxxxxxxxxxxxxxxxx >> > http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies >> > > > _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
