On Tue, 04 Jun 2024 10:45:37 +0300 Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx> wrote: > On Sun, 02 Jun 2024, Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> wrote: > > Make two APIs look similar. Hence convert match_string() to be > > a 2-argument macro. In order to avoid unneeded churn, convert > > all users as well. There is no functional change intended. > > Why do we think it's a good idea to increase and normalize the use of > double-underscore function names across the kernel, like > __match_string() in this case? It should mean "reserved for the > implementation, not to be called directly". > > If it's to be used directly, it should be named accordingly, right? > > Being in line with __sysfs_match_string() isn't a great argument alone, > because this adds three times the number of __match_string() calls than > there are __sysfs_match_string() calls. It's not a good model to follow. > Arguably both should be renamed. Agreed. I want to get rid of any functions starting with an underscore except for those that are basically the same function used internally for convenience. Perhaps "match_string_dynamic()"? Where it is used for dynamically allocated arrays without known size. Or, allow a third parameter for dynamic arrays. #define match_string(_a, _s, ...) char _______STR[] = __stringify((__VA_ARGS__)); \ if (sizeof(_______STR) > 3) \ __match_string(_a, _s, ##__VA_ARGS__); \ else \ __match_string(_a, _s, ARRAY_SIZE(_a)); What the above stringify((__VA_ARGS__)) does is to check the size of any args added to match_string(). if there isn't any, it will turn into: "()\0", which is of size 3. If you add an argument, it will be: "(<arg>)\0", which will have a size greater than three. (trace_printk() does this trick in include/linux/kernel.h). This way, both: match_string(array, sting); or match_string(array, string, size); will work. -- Steve
