Messages in this thread | | | From | Nick Piggin <> | Subject | Re: 2.6.24-git: kmap_atomic() WARN_ON() | Date | Wed, 27 Feb 2008 10:49:34 +1100 |
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On Wednesday 27 February 2008 07:49, Ingo Molnar wrote: > * Andrew Morton <akpm@linux-foundation.org> wrote: > > > This is only being done to satisfy kmap_atomic's requirements, not > > > libata's. > > > > > > I could add a "kmap lock" but that just seems silly. > > > > It's a bit sad to disable interupts across a memset (how big is it?) > > just for the small proportion of cases which are accessing a highmem > > page. > > > > What you could do is to add an `unsigned long *flags' arg to > > ata_scsi_rbuf_get() and ata_scsi_rbuf_put(), and then, in > > ata_scsi_rbuf_get() do > > > > if (PageHighmem(page)) > > local_irq_disable(*flags); > > it would be much nicer to attach the irq disabling to the object, not to > some arbitrary place in the code. > > i.e. to introduce a kmap_atomic_irqsave(...,flags) and > kunmap_atomic_irqrestore() API variant. _That_ then could be mapped by > -rt to a non-irq disabling thing.
Yeah that is the right way to fix it, but that name implies that interrupts are disabled for non-highmem pages too, which we don't want. Can you think of a better one?
kmap_atomic_irq_safe maybe?
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