Frank Rowand <frowand.list@xxxxxxxxx> writes: > On 2/19/19 10:34 PM, Brendan Higgins wrote: >> On Mon, Feb 18, 2019 at 12:02 PM Frank Rowand <frowand.list@xxxxxxxxx> wrote: >> <snip> >>> I have not read through the patches in any detail. I have read some of >>> the code to try to understand the patches to the devicetree unit tests. >>> So that may limit how valid my comments below are. >> >> No problem. >> >>> >>> I found the code difficult to read in places where it should have been >>> much simpler to read. Structuring the code in a pseudo object oriented >>> style meant that everywhere in a code path that I encountered a dynamic >>> function call, I had to go find where that dynamic function call was >>> initialized (and being the cautious person that I am, verify that >>> no where else was the value of that dynamic function call). With >>> primitive vi and tags, that search would have instead just been a >>> simple key press (or at worst a few keys) if hard coded function >>> calls were done instead of dynamic function calls. In the code paths >>> that I looked at, I did not see any case of a dynamic function being >>> anything other than the value it was originally initialized as. >>> There may be such cases, I did not read the entire patch set. There >>> may also be cases envisioned in the architects mind of how this >>> flexibility may be of future value. Dunno. >> >> Yeah, a lot of it is intended to make architecture specific >> implementations and some other future work easier. Some of it is also >> for testing purposes. Admittedly some is for neither reason, but given >> the heavy usage elsewhere, I figured there was no harm since it was >> all private internal usage anyway. >> > > Increasing the cost for me (and all the other potential code readers) > to read the code is harm. Dynamic function calls aren't necessary for arch-specific implementations either. See for example arch_kexec_image_load() in kernel/kexec_file.c, which uses a weak symbol that is overriden by arch-specific code. Not everybody likes weak symbols, so another alternative (which admitedly not everybody likes either) is to use a macro with the name of the arch-specific function, as used by arch_kexec_post_alloc_pages() in <linux/kexec.h> for instance. -- Thiago Jung Bauermann IBM Linux Technology Center
