Messages in this thread | | | Date | Wed, 10 Feb 2021 15:16:03 +1100 (AEDT) | From | Finn Thain <> | Subject | RE: [Linuxarm] Re: [PATCH for-next 00/32] spin lock usage optimization for SCSI drivers |
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On Tue, 9 Feb 2021, Song Bao Hua (Barry Song) wrote:
> > > sonic_interrupt() uses an irq lock within an interrupt handler to > > > avoid issues relating to this. This kind of locking may be needed in > > > the drivers you are trying to patch. Or it might not. Apparently, > > > no-one has looked. > > Is the comment in sonic_interrupt() outdated according to this: > m68k: irq: Remove IRQF_DISABLED > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=77a4279 > http://lkml.iu.edu/hypermail/linux/kernel/1109.2/01687.html >
The removal of IRQF_DISABLED isn't relevant to this driver. Commit 77a42796786c ("m68k: Remove deprecated IRQF_DISABLED") did not disable interrupts, it just removed some code to enable them.
The code and comments in sonic_interrupt() are correct. You can confirm this for yourself quite easily using QEMU and a cross-compiler.
> and this: > genirq: Warn when handler enables interrupts > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b738a50a > > wouldn't genirq report a warning on m68k? >
There is no warning from m68k builds. That's because arch_irqs_disabled() returns true when the IPL is non-zero.
> > > > Thanks > > Barry > > Thanks > Barry > >
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