On 24.04.19 23:18, Thomas Gleixner wrote: Hi, >> +config PROC_PID_ARCH_STATUS >> + bool "Enable /proc/<pid>/arch_status file" > > Why is this switchable? x86 selects it if PROC_FS is enabled and all other > architectures are absolutely not interested in this. IMHO, it's good to have a switch, but that way doesn't make much sense. Instead, I'd do it the other way round: make that switch depending on those archs that actually support it. Something like this: config PROC_PID_ARCH_STATUS bool "Enable /proc/<pid>/arch_status file" depends on PROC_FS depends on BROKEN When x86 comes in, it would change to: config PROC_PID_ARCH_STATUS bool "Enable /proc/<pid>/arch_status file" depends on PROC_FS depends on X86 And later arm coming in: config PROC_PID_ARCH_STATUS bool "Enable /proc/<pid>/arch_status file" depends on PROC_FS depends on X86 || ARM >> + default n >> + help >> + Provides a way to examine process architecture specific information. >> + See <file:Documentation/filesystems/proc.txt> for more information. > > Which contains zero information about this file when only this patch is > applied. hmm, the patch alone doesn't do anything useful anyway. it only becomes useful with subsequent patches that add some arch. I wonder if there's anything more useful to document at that point. >> +/* >> + * Add support for task architecture specific output in /proc/pid/arch_status. >> + * task_arch_status() must be defined in asm/processor.h >> + */ >> +#ifdef CONFIG_PROC_PID_ARCH_STATUS >> +# ifndef task_arch_status >> +# define task_arch_status(m, task) >> +# endif > > What exactly is the point of this macro mess? If an architecture selects > CONFIG_PROC_PID_ARCH_STATUS then it has to provide proc_task_arch_status() > and the prototype should be in include/linux/proc_fs.h. ACK. >> +static int proc_pid_arch_status(struct seq_file *m, struct pid_namespace *ns, >> + struct pid *pid, struct task_struct *task) >> +{ >> + task_arch_status(m, task); >> + return 0; >> +} Is that wrapper really neeeded ? --mtx -- Enrico Weigelt, metux IT consult Free software and Linux embedded engineering info@xxxxxxxxx -- +49-151-27565287