Sergei Shtylyov writes: > Hello. > > Hugh Dickins wrote: > > >> Commit 871af1210f13966ab911ed2166e4ab2ce775b99d (libata: Add 32bit PIO support) > >> caused all kind of errors on the ATAPI devices, so it's been empirically proven > >> that one shouldn't read/write an extra data word when a device isn't expecting > >> it already. "Don't do it then"; however still taking a chance to use 32-bit I/O > >> one last time when there are exactly 3 trailing bytes. Oh, and stop pointless > >> swapping bytes to and fro as well by using io*_rep() which shouldn't byte-swap. > >> > >> This should fix the kernel.org bug #12609. > >> > >> --- > >> This is hopefully better replacement for Hugh Dickins most recent patch > >> (http://marc.info/?l=linux-ide&m=123352294619281)... > >> > > > > Yes, looks nice, and works for me. My only criticism would be, > > minor issue unchanged by your patch, that actually "slop" isn't > > unlikely enough to deserve an "unlikely" - slop of 1 or 3 is > > unlikely, but slop of 2 is quite common. > > > > I guess that's the case only for the ATAPI devices, so I'm going to > keep it. I really don't think it's a good idea to play micro-optimisation unlikely() tricks when the likelihood depends on what kind of device the driver is talking to. In this case unlikely() is clearly wrong. -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
