Messages in this thread | | | From | Bartlomiej Zolnierkiewicz <> | Subject | Re: [PATCH 2/6] ide: move SFF I/O code to ide-io-sff.c | Date | Mon, 19 Jan 2009 20:12:51 +0100 |
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On Monday 19 January 2009, Alan Cox wrote: > > Tried looking at how in*()/out*() are defined on x86? > > Tried looking at how ide_mm_inb is defined on x86 > > > > It's already making function calls, without the benefit of inlining and > > > > I'm afraid you're wrong here. > > I'm afraid you are the one who is wrong. The IDE layer is duplicating a > generic level of indirection with its own code - purely because IDE > pre-dates that core functionality. The whole IDE layer indirection can go > away because Linux has caught up with the needs of the IDE layer.
I wish it would be so simple as I would have removed the said indirection long time ago. Unfortunately:
- not all archs support ioread() & co.
- there is still issue with cache aliasing on some CPUs
Once above deficiences get fixed we can look into ioread() conversion again.
[ IOW right now it is the correct thing to stick to ide_mm_*() indirection since extra hardware coverage is more valuable than minor code cleanup. ]
Thanks, Bart
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