Messages in this thread | | | Subject | Re: [PATCH 2/5] ftrace: use code patching for ftrace graph tracer | From | Harvey Harrison <> | Date | Wed, 26 Nov 2008 10:06:00 -0800 |
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On Wed, 2008-11-26 at 10:02 -0800, Andrew Morton wrote: > > > > > > > + return -EINVAL; > > > > + > > > > + *(int *)(&code[1]) = new_offset; > > > > > > Might be able to use put_unaligned_foo() here. > > > > > > The problem is that these functions use sizeof(*ptr) to work out what > > > to do, so a cast is still needed. A get_unaligned32(ptr) would be > > > nice. One which takes a void* and assumes CPU ordering. > > > > Is there a correctness concern here? This is arch specific code, so I'm > > not worried about other archs. > > No, the code is OK as-is. > > It's just that "read a word from an [maybe-]unaligned address" is such > a common operation that there should be a nice clean simple function to > do it, rather than doing open-coded (and different) weird C tricks at each > and\ every site. >
Also it is arch-specific, so if you know unaligned access is OK, just doing the cast+deref is OK.
Harvey
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