Messages in this thread | | | Date | Tue, 1 Jun 1999 16:33:21 +0200 | From | Jamie Lokier <> | Subject | Re: howto avoid optimizing a read? |
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Alan Cox wrote: > > Whats the easiest way to avoid having the read optimized away? I am > > fairly fluent in C, but compiler optimizations are bit too much black > > magic for me. > > Look up the volatile keyword in a C manual. It exists for exactly these > sort of occasions.
The documentation says to use readb/readw/readl to read memory-mapped devices, and they use volatile already so use them.
Don't read existing device drivers, you might learn bad habits. :-)
References: Documentation/IO-mapping.txt, <asm/io.h>
-- Jamie
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