> On Dec 2, 2015, at 13:04, Vlastimil Babka <vbabka@xxxxxxx> wrote: > > On 12/02/2015 06:40 PM, yalin wang wrote: > > (please trim your reply next time, no need to quote whole patch here) > >> i am thinking why not make %pg* to be more generic ? >> not restricted to only GFP / vma flags / page flags . >> so could we change format like this ? >> define a flag spec struct to include flag and trace_print_flags and some other option : >> typedef struct { >> unsigned long flag; >> structtrace_print_flags *flags; >> unsigned long option; } flag_sec; >> flag_sec my_flag; >> in printk we only pass like this : >> printk(“%pg\n”, &my_flag) ; >> then it can print any flags defined by user . >> more useful for other drivers to use . > > I don't know, it sounds quite complicated given that we had no flags printing > for years and now there's just three kinds of them. The extra struct flag_sec is > IMHO nuissance. No other printk format needs such thing AFAIK? For example, if I > were to print page flags from several places, each would have to define the > struct flag_sec instance, or some header would have to provide it? this can be avoided by provide a macro in header file . we can add a new struct to declare trace_print_flags : for example: #define DECLARE_FLAG_PRINTK_FMT(name, flags_array) flag_spec name = { .flags = flags_array}; #define FLAG_PRINTK_FMT(name, flag) ({ name.flag = flag; &name}) in source code : DECLARE_FLAG_PRINTK_FMT(my_flag, vmaflags_names); printk(“%pg\n”, FLAG_PRINTK_FMT(my_flag, vma->flag)); i am not if DECLARE_FLAG_PRINTK_FMT and FLAG_PRINTK_FMT macro can be defined into one macro ? maybe need some trick here . is it possible ? Thanks -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href